# Colorectal Cancer — GCMD Library living collection

Everything in the library about colorectal cancer — built automatically from dossiers that name it.

Updated: n/a · 4 episodes · 104 cited statements

## Episodes
### Evidence & Research
- [Best of the Best Gen Surg - Development of postoperative local tumors and distant metastases in diet, genetics and microbiome-dependent in a mouse model of colorectal cancer recurrence - Dr. Morgan](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861) — video · 12:40 · [machine version](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861.md)

### In-Depth Reviews
- [Colorectal Cancer](https://library.globalcastmd.com/watch/colorectal-cancer-13749) — podcast · 26:42 · [machine version](https://library.globalcastmd.com/watch/colorectal-cancer-13749.md)
- [Colorectal Cancer](https://library.globalcastmd.com/watch/colorectal-cancer-13750) — podcast · 26:42 · [machine version](https://library.globalcastmd.com/watch/colorectal-cancer-13750.md)
- [Colorectal Cancer](https://library.globalcastmd.com/watch/colorectal-cancer-13754) — podcast · 26:42 · [machine version](https://library.globalcastmd.com/watch/colorectal-cancer-13754.md)

## Chapters
- [0:00](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=0) Introduction and Paper Title (Ep 1)
- [0:34](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=34) Background and Novel Recurrence Model (Ep 1)
- [2:04](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=124) Study Hypothesis and Methods (Ep 1)
- [3:07](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=187) Tumor Formation Results by Diet and Cell Line (Ep 1)
- [4:24](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=264) Microbiome Mediation via Fecal Transplant (Ep 1)
- [5:24](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=324) Diet Reversal and Microbiome Analysis (Ep 1)
- [7:01](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=421) Summary and Acknowledgments (Ep 1)
- [7:52](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=472) Discussion and Q&A (Ep 1)
- [0:00](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=0) Introduction and colonoscopy screening (Ep 2)
- [2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=123) Serrated adenomas: recognition and management (Ep 2)
- [4:16](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=256) Rectal cancer: location and surgical margins (Ep 2)
- [9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543) Rectal cancer staging: MRI versus ultrasound (Ep 2)
- [14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=847) Transanal resection: indications and limitations (Ep 2)
- [16:58](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1018) Neoadjuvant therapy for rectal cancer (Ep 2)
- [19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162) Sigmoid and left colon cancer surgery (Ep 2)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1349) Right colon and cecal cancer surgery (Ep 2)
- [24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1453) Genetic assessment and hereditary syndromes (Ep 2)
- [0:00](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=0) Introduction and colonoscopy screening (Ep 3)
- [2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=123) Serrated adenomas: recognition and management (Ep 3)
- [4:16](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=256) Rectal cancer: location and surgical margins (Ep 3)
- [9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543) Rectal cancer staging: MRI versus ultrasound (Ep 3)
- [14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847) Transanal resection: indications and limitations (Ep 3)
- [16:58](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1018) Neoadjuvant therapy for rectal cancer (Ep 3)
- [19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162) Sigmoid and left colon cancer surgery (Ep 3)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1349) Right colon and cecal cancer surgery (Ep 3)
- [24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1453) Genetic assessment and hereditary syndromes (Ep 3)
- [0:00](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=0) Introduction and colonoscopy screening (Ep 4)
- [2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=123) Serrated adenomas: recognition and management (Ep 4)
- [4:15](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=255) Rectal cancer: location, margins, and surgical planning (Ep 4)
- [9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543) Rectal cancer staging: MRI versus ultrasound (Ep 4)
- [14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=847) Transanal resection: indications and limitations (Ep 4)
- [16:58](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1018) Neoadjuvant radiation therapy for rectal cancer (Ep 4)
- [19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162) Sigmoid and left colon cancer: surgical technique (Ep 4)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1349) Right colon cancer: extent of resection (Ep 4)
- [24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1453) Genetic assessment in colorectal cancer (Ep 4)

## Statements
Every statement is attributed, typed, and timestamped; the link is the citation.
- "Colorectal cancer is a leading cause of cancer deaths, particularly in cases of recurrence." — Ryan Morgan (epidemiological) [Ep 1 · 0:45](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=45)
- "Traditional paradigms suggest recurrences are due to either incomplete resection or occult metastases left behind at the time of surgery." — Ryan Morgan (host_summary) [Ep 1 · 0:45](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=45)
- "Exfoliated cancer cells in the lumen of the bowel may be a source of recurrence." — Ryan Morgan (host_summary) [Ep 1 · 0:58](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=58)
- "In the 1980s, UMLB showed that exfoliated cancer cells are present and viable at the time of surgery." — Ryan Morgan (host_summary) [Ep 1 · 1:04](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=64)
- "Experimental cells could cross a watertight anastomosis in a mouse model." — Ryan Morgan (host_summary) [Ep 1 · 1:09](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=69)
- "Rectal washout decreases rates of local recurrence after rectal cancer resection." — Ryan Morgan (host_summary) [Ep 1 · 1:14](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=74)
- "When the primary colorectal tumor is resected, exfoliated cells remain behind within the lumen of the bowel and interact with the anastomotic microenvironment." — Ryan Morgan (clinical) [Ep 1 · 1:39](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=99)
- "Multiple factors can influence the anastomotic environment, including diet, the microbiome, and the tumor genetic background." — Ryan Morgan (clinical) [Ep 1 · 1:48](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=108)
- "A high-fat diet and its impact on the microbiome would alter the anastomotic environment and change the metastatic potential of cells." — Ryan Morgan (clinical) [Ep 1 · 2:04](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=124)
- "AKPT and KPN organoid cell lines demonstrate a wide range of metastatic potential in animal models." — Ryan Morgan (host_summary) [Ep 1 · 2:15](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=135)
- "AKPT mice showed significantly higher rate of tumor formation with a high-fat diet compared to mice given a chow diet by 56 days." — Ryan Morgan (clinical) [Ep 1 · 3:35](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=215)
- "KPN mice showed no significant difference in tumor formation based on diet, with an opposite trend towards higher rates in the chow diet." — Ryan Morgan (clinical) [Ep 1 · 3:46](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=226)
- "AKPT mice given a high-fat diet had significantly decreased survival compared to those on a chow diet." — Ryan Morgan (clinical) [Ep 1 · 4:08](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=248)
- "KPN mice did not show any similar survival trend, suggesting that response to diet was at least in part based on the organoid genetic background." — Ryan Morgan (clinical) [Ep 1 · 4:14](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=254)
- "In germ-free mice, the high-fat diet-associated microbiome significantly increased the rate of postoperative tumor development (40% vs 10-12% in control and chow FMT groups)." — Ryan Morgan (clinical) [Ep 1 · 4:57](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=297)
- "Two-week diet reversal period was insufficient; mice in the reversal group continued to have poor survival and high tumor rates similar to the high-fat diet group." — Ryan Morgan (clinical) [Ep 1 · 5:50](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=350)
- "Six-week diet reversal resulted in significantly increased survival and tumor rate similar to chow-fed mice, suggesting the response to diet and its reversal was time dependent." — Ryan Morgan (clinical) [Ep 1 · 6:01](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=361)
- "High-fat diet mice showed derangement of microbiome with overabundance of Alobaum and bloom of pathogenic bacteria such as Proteus, E. coli, and Shigella on postoperative day 7." — Ryan Morgan (clinical) [Ep 1 · 6:30](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=390)
- "The diet reversal group microbiome composition closely mirrored the chow group both in baseline composition and in response to surgery." — Ryan Morgan (clinical) [Ep 1 · 6:45](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=405)
- "Preoperative diet manipulation reduces tumor formation, suggesting a clinically relevant role for diet rehabilitation in colorectal cancer treatment." — Ryan Morgan (opinion) [Ep 1 · 7:23](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=443)
- "The no-touch isolation technique of Turnbull was important in demonstrating the need to avoid handling the tumor." (host_summary) [Ep 1 · 8:20](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=500)
- "Combined mechanical and antibiotic bowel preparation preoperatively decreases rates of colorectal cancer recurrence." — Ryan Morgan (host_summary) [Ep 1 · 9:23](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=563)
- "Preliminary in vitro data shows AKPT cells have more proliferative response to secondary bile acids (like deoxycholic acid) compared to KPN cells." — Ryan Morgan (clinical) [Ep 1 · 11:05](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=665)
- "Secondary bile acids and deoxycholic acid metabolites are exclusively bacterially produced." — Ryan Morgan (clinical) [Ep 1 · 11:05](https://library.globalcastmd.com/watch/best-of-the-best-gen-surg-development-of-postoperative-local-tumors-and-distant-metastases-in-diet-genetics-and-microbiome-dependent-in-a-mouse-model-of-colorectal-cancer-recurrence-dr-morgan-5861?t=665)
- "Colonoscopy is still the best test available for colon cancer detection, finding the vast majority of cancers and polyps, though not perfect." — Conor Delaney (clinical) [Ep 2 · 1:15](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=75)
- "Serrated adenomas (previously misclassified as hyperplastic polyps) have good evidence of genetic predisposition and tie into many family cancer syndromes." — Conor Delaney (clinical) [Ep 2 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=123)
- "Serrated polyps have a very high risk of cancer and require family assessment to determine if patients have a family cancer syndrome." — Conor Delaney (clinical) [Ep 2 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=123)
- "Serrated adenomas are often flat and difficult to see; retroflexion in the cecum is useful because they are often on the inferior or superior side of the valve or on folds." — Conor Delaney (clinical) [Ep 2 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=206)
- "Six centimeters from the anal verge can be mid-rectum in a small patient (90-pound, 80-year-old female) or close to the dentate line in a large patient (6'6", 300 pounds)." — Conor Delaney (clinical) [Ep 2 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=299)
- "Distal margin requirements for rectal resection: 5 centimeters if possible, 2 centimeters if possible, and for very lowest tumors perhaps 1 centimeter as long as they are not poorly differentiated." — Conor Delaney (guideline) [Ep 2 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=299)
- "MRI is probably 90 to mid-90s percent accurate at T staging and high 80s to 90% accurate for nodal staging in rectal cancer." — Conor Delaney (clinical) [Ep 2 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=798)
- "Endoscopic ultrasound is much more operator dependent and probably only 70% accurate for predicting nodal involvement in rectal cancer." — Conor Delaney (clinical) [Ep 2 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=798)
- "Historical local recurrence rates for rectal cancer from good institutions were 20 to 38 percent, with some up to 50 percent." — Conor Delaney (epidemiological) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "With optimized surgery, imaging, and patient selection, local recurrence rates for rectal cancer should be under 10 percent; Cleveland Clinic's rate over the last 10 years was about 3 percent." — Conor Delaney (epidemiological) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "For total mesorectal excision, the circumferential resection margin should be one to two millimeters; if threatened, this is an indication for neoadjuvant therapy or extended resection." — Conor Delaney (guideline) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "A total mesorectal excision can be performed with about 5 milliliters of blood loss because it is a bloodless plane; bleeding indicates being outside that plane or in the wrong plane." — Conor Delaney (clinical) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "Most accepted guidelines for neoadjuvant therapy in rectal cancer are for tumors that are T3 (outside the wall of the rectum) or node positive." — Conor Delaney (guideline) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "For node-negative T1 or T2 rectal tumors (stage one), particularly if upper third, neoadjuvant therapy can be omitted." — Conor Delaney (guideline) [Ep 2 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=791)
- "Historical local recurrence rates for transanally excised rectal cancers were about 18%, remarkably consistent across outcome data from several big centers." — Conor Delaney (epidemiological) [Ep 2 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=847)
- "Transanal resection is generally appropriate for tumors less than a third of the circumference, ideally less than two centimeters, that are T1." — Conor Delaney (guideline) [Ep 2 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=847)
- "For young, curable patients, most surgeons favor radical resection over transanal resection; transanal resection is generally kept for patients unfit for rectal resection or those whose tumor is so close to the dentate line that a permanent stoma would be required." — Conor Delaney (opinion) [Ep 2 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=847)
- "For rectal cancer, full-thickness excision is required; ESD (endoscopic submucosal dissection) would never be done for a proven cancer, only for benign polyps." — Conor Delaney (clinical) [Ep 2 · 16:23](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=983)
- "In Europe, short-course radiation is five times five gray given over five days, with surgery about one to two weeks later." — Conor Delaney (guideline) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "In the U.S., long-course radiation is 40 to 45 gray given with chemotherapy over six weeks, followed by a six to eight week waiting period." — Conor Delaney (guideline) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "Twenty-five gray over a short period is radiotherapeutically equivalent to 40 to 45 gray over a longer period, but longer course can make a big difference for tumor response and physical downstaging." — Conor Delaney (clinical) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "For colon cancer surgery, goals include at least a 5 centimeter proximal and distal margin (usually determined by blood supply) and at least 12 lymph nodes, with many surgeons hoping for at least 16." — Conor Delaney (guideline) [Ep 2 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162)
- "Total mesocolic excision should be performed in the plane between the embryological peritoneum of the retroperitoneum (Toldt's fascia) and the embryological peritoneum on the mesocolon, keeping the mesocolon complete." — Conor Delaney (clinical) [Ep 2 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162)
- "Scandinavian data showed local recurrence rates for colon cancer were even higher than for rectal cancer (which was high 20s percent) because they realized they weren't doing adequate colon cancer surgery." — Conor Delaney (epidemiological) [Ep 2 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162)
- "For a cecal tumor or lesion near the ileocecal valve, 10 centimeters of small bowel should be taken; for mid-ascending colon, 5 centimeters should be taken." — Conor Delaney (guideline) [Ep 2 · 22:44](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1364)
- "Extracorporeal stapled anastomosis for right colectomy has reported leak rates of 0.8% over 1,000 cases at Cleveland Clinic." — Conor Delaney (epidemiological) [Ep 2 · 23:59](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1439)
- "Genetic workup should be considered for patients with cancer under age 40, first-degree relatives with cancer, multiple cancers in a family, or non-GI cancers in a family." — Conor Delaney (guideline) [Ep 2 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1472)
- "Genetic findings may change the surgical operation: a patient with a right colon cancer plus multiple polyps or significant family history may be better served with a subtotal colectomy rather than segmental resection." — Conor Delaney (clinical) [Ep 2 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1472)
- "Colonoscopy is still the best test available for colon cancer detection, finding the vast majority of cancers and polyps, though not perfect." — Conor Delaney (clinical) [Ep 3 · 1:15](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=75)
- "Serrated adenomas (previously misclassified as hyperplastic polyps) have good evidence of genetic predisposition and tie into many family cancer syndromes." — Conor Delaney (clinical) [Ep 3 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=123)
- "Serrated polyps have a very high risk of cancer and require family assessment to determine if patients have a family cancer syndrome." — Conor Delaney (clinical) [Ep 3 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=123)
- "Serrated adenomas are often flat and difficult to see; retroflexion in the cecum is useful because they are often on the inferior or superior side of the valve or on folds." — Conor Delaney (clinical) [Ep 3 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=206)
- "Six centimeters from the anal verge can be mid-rectum in a small patient (90-pound, 80-year-old female) or close to the dentate line in a large patient (6'6", 300 pounds)." — Conor Delaney (clinical) [Ep 3 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=299)
- "Distal margin requirements for rectal resection: 5 centimeters if possible, 2 centimeters if possible, and for very lowest tumors perhaps 1 centimeter as long as they are not poorly differentiated." — Conor Delaney (guideline) [Ep 3 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=299)
- "MRI is probably 90 to mid-90s percent accurate at T staging and high 80s to 90% accurate for nodal staging in rectal cancer." — Conor Delaney (clinical) [Ep 3 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=798)
- "Endoscopic ultrasound is much more operator dependent and probably only 70% accurate for predicting nodal involvement in rectal cancer." — Conor Delaney (clinical) [Ep 3 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=798)
- "Historical local recurrence rates for rectal cancer from good institutions were 20 to 38 percent, with some up to 50 percent." — Conor Delaney (epidemiological) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "With optimized surgery, imaging, and patient selection, local recurrence rates for rectal cancer should be under 10 percent; Cleveland Clinic's rate over the last 10 years was about 3 percent." — Conor Delaney (epidemiological) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "For total mesorectal excision, the circumferential resection margin should be one to two millimeters; if threatened, this is an indication for neoadjuvant therapy or extended resection." — Conor Delaney (guideline) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "A total mesorectal excision can be performed with about 5 milliliters of blood loss because it is a bloodless plane; bleeding indicates being outside that plane or in the wrong plane." — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Most accepted guidelines for neoadjuvant therapy in rectal cancer are for tumors that are T3 (outside the wall of the rectum) or node positive." — Conor Delaney (guideline) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "For node-negative T1 or T2 rectal tumors (stage one), particularly if upper third, neoadjuvant therapy can be omitted." — Conor Delaney (guideline) [Ep 3 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=791)
- "Historical local recurrence rates for transanally excised rectal cancers were about 18%, remarkably consistent across outcome data from several big centers." — Conor Delaney (epidemiological) [Ep 3 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847)
- "Transanal resection is generally appropriate for tumors less than a third of the circumference, ideally less than two centimeters, that are T1." — Conor Delaney (guideline) [Ep 3 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847)
- "For young, curable patients, most surgeons favor radical resection over transanal resection; transanal resection is generally kept for patients unfit for rectal resection or those whose tumor is so close to the dentate line that a permanent stoma would be required." — Conor Delaney (opinion) [Ep 3 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847)
- "For rectal cancer, full-thickness excision is required; ESD (endoscopic submucosal dissection) would never be done for a proven cancer, only for benign polyps." — Conor Delaney (clinical) [Ep 3 · 16:23](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=983)
- "In Europe, short-course radiation is five times five gray given over five days, with surgery about one to two weeks later." — Conor Delaney (guideline) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "In the U.S., long-course radiation is 40 to 45 gray given with chemotherapy over six weeks, followed by a six to eight week waiting period." — Conor Delaney (guideline) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "Twenty-five gray over a short period is radiotherapeutically equivalent to 40 to 45 gray over a longer period, but longer course can make a big difference for tumor response and physical downstaging." — Conor Delaney (clinical) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "For colon cancer surgery, goals include at least a 5 centimeter proximal and distal margin (usually determined by blood supply) and at least 12 lymph nodes, with many surgeons hoping for at least 16." — Conor Delaney (guideline) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "Total mesocolic excision should be performed in the plane between the embryological peritoneum of the retroperitoneum (Toldt's fascia) and the embryological peritoneum on the mesocolon, keeping the mesocolon complete." — Conor Delaney (clinical) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "Scandinavian data showed local recurrence rates for colon cancer were even higher than for rectal cancer (which was high 20s percent) because they realized they weren't doing adequate colon cancer surgery." — Conor Delaney (epidemiological) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "For a cecal tumor or lesion near the ileocecal valve, 10 centimeters of small bowel should be taken; for mid-ascending colon, 5 centimeters should be taken." — Conor Delaney (guideline) [Ep 3 · 22:44](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1364)
- "Extracorporeal stapled anastomosis for right colectomy has reported leak rates of 0.8% over 1,000 cases at Cleveland Clinic." — Conor Delaney (epidemiological) [Ep 3 · 23:59](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1439)
- "Genetic workup should be considered for patients with cancer under age 40, first-degree relatives with cancer, multiple cancers in a family, or non-GI cancers in a family." — Conor Delaney (guideline) [Ep 3 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1472)
- "Genetic findings may change the surgical operation: a patient with a right colon cancer plus multiple polyps or significant family history may be better served with a subtotal colectomy rather than segmental resection." — Conor Delaney (clinical) [Ep 3 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1472)
- "Colonoscopy is still the best test for colon cancer detection, with approximately 90-95% accuracy for finding cancers and polyps, though not perfect." — Conor Delaney (clinical) [Ep 4 · 1:15](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=75)
- "Serrated adenomas (previously misclassified as hyperplastic polyps) have a very high risk of cancer and are associated with genetic predisposition and family cancer syndromes." — Conor Delaney (clinical) [Ep 4 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=123)
- "Serrated adenomas require family assessment, may necessitate altered colonoscopy frequency, and family members may need colonoscopy or other testing." — Conor Delaney (guideline) [Ep 4 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=123)
- "Serrated polyps are often flat and difficult to see; retroflexion in the cecum is useful because they are often on the inferior or superior side of the valve or on folds." — Conor Delaney (clinical) [Ep 4 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=206)
- "For rectal cancer, distal margin requirements are 5 cm if achievable, 2 cm if achievable, and for very low tumors 1 cm is acceptable as long as they are not poorly differentiated." — Conor Delaney (guideline) [Ep 4 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=299)
- "Six centimeters from the anal verge can mean different things depending on patient size: in a small elderly female it may be mid-rectum, while in a large male it can be near the dentate line." — Conor Delaney (clinical) [Ep 4 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=299)
- "Upper third rectal cancers likely do not need preoperative therapy or stoma, while middle and lower third cancers have a good chance of needing neoadjuvant therapy and temporary or rarely permanent stoma." — Conor Delaney (clinical) [Ep 4 · 6:51](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=411)
- "Distant staging for rectal cancer is best done with CT abdomen for liver assessment and CT chest (now preferred over chest x-ray per most guidelines)." — Conor Delaney (guideline) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "MRI with high-resolution, high Tesla magnet and standardized protocol (developed by Bill Heald and Gina Brown at Royal Marsden) is now the standard for local staging of rectal cancer." — Conor Delaney (guideline) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "MRI is approximately 90-95% accurate for T staging and high 80s to 90% accurate for nodal staging in rectal cancer." — Conor Delaney (clinical) [Ep 4 · 10:43](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=643)
- "Endoscopic ultrasound is only about 70% accurate for predicting nodal involvement in rectal cancer and is much more operator dependent than MRI." — Conor Delaney (clinical) [Ep 4 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=791)
- "Historical local recurrence rates for rectal cancer from good institutions were 20-38%, with some up to 50%, but with optimized surgery and imaging should now be under 10%." — Conor Delaney (epidemiological) [Ep 4 · 10:43](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=643)
- "Cleveland Clinic's local recurrence rate for rectal cancer over the last 10 years was approximately 3%." — Conor Delaney (epidemiological) [Ep 4 · 10:43](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=643)
- "Circumferential resection margin is the most important margin in rectal cancer surgery; a negative pathological margin results in low chance of local recurrence." — Conor Delaney (clinical) [Ep 4 · 10:43](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=643)
- "Total mesorectal excision (TME) can be performed with about 5 mL of blood loss because it is a bloodless plane; bleeding indicates being outside that plane or deliberately in the wrong plane." — Conor Delaney (clinical) [Ep 4 · 10:43](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=643)
- "Neoadjuvant therapy is indicated for rectal tumors that are T3 (outside the wall) or node positive." — Conor Delaney (guideline) [Ep 4 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=791)
- "Stage I rectal cancer (node negative and T1 or T2), particularly if upper third, does not require preoperative radiation." — Conor Delaney (guideline) [Ep 4 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=791)
- "Historical local recurrence rates for transanally excised rectal cancers were approximately 18%, remarkably consistent across several major centers." — Conor Delaney (epidemiological) [Ep 4 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=847)
- "Transanal resection is appropriate for tumors less than one-third circumference, ideally less than 2 cm, that are T1." — Conor Delaney (guideline) [Ep 4 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=847)
- "For young, curable patients, radical resection is generally favored over transanal resection; transanal approaches are reserved for patients unfit for rectal resection or those whose tumor location would require permanent stoma." — Conor Delaney (opinion) [Ep 4 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=847)
- "Rectal cancer requires full-thickness excision; endoscopic submucosal dissection (ESD) would never be used for proven or high-risk cancer, only for benign polyps." — Conor Delaney (guideline) [Ep 4 · 15:58](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=958)
- "Short-course radiation (5×5 Gy over 5 days, surgery 1-2 weeks later) is preferred in Europe, while long-course chemoradiation (40-45 Gy over 6 weeks with 6-8 week wait) is preferred in the U.S." — Conor Delaney (guideline) [Ep 4 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1045)
- "25 Gy over a short period is radiotherapeutically equivalent to 40-45 Gy over a longer period, but long-course therapy produces greater tumor downstaging and is preferred for bulky tumors." — Conor Delaney (clinical) [Ep 4 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1045)
- "For colon cancer, surgeons should aim for at least 12 lymph nodes, though many hope for at least 16." — Conor Delaney (guideline) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "High ligation of the inferior mesenteric artery (above the takeoff of the left colic artery) is performed in sigmoid colectomy, with protection of autonomic nerves to preserve sexual function." — Conor Delaney (clinical) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "Total mesocolic excision should be performed in the plane between Toltz fascia (retroperitoneal embryological peritoneum) and the mesocolon peritoneum, achieving complete mesocolic specimen with minimal blood loss." — Conor Delaney (clinical) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "Scandinavian data showed local recurrence rates for colon cancer were higher than for rectal cancer (despite rectal rates of high 20s) because adequate colon cancer surgery technique was not being performed." — Conor Delaney (epidemiological) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "For mid-sigmoid cancer (35-40 cm), resection can extend from mid-descending colon to rectosigmoid junction without necessarily taking the splenic flexure, provided there is good vascularity with pulsatile flow." — Conor Delaney (clinical) [Ep 4 · 21:23](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1283)
- "For cecal tumors, 10 cm of small bowel should be taken; for mid-ascending colon tumors, 5 cm of small bowel is adequate." — Conor Delaney (guideline) [Ep 4 · 22:44](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1364)
- "Extracorporeal stapled anastomosis through the extraction site for laparoscopic right colectomy has achieved leak rates of 0.8% over 1,000 cases at Cleveland Clinic." — Conor Delaney (epidemiological) [Ep 4 · 23:55](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1435)
- "Cleveland Clinic has a low threshold for genetic assessment, consulting coordinators when patients meet Bethesda criteria, have first-degree relatives with cancer, young family members with cancer, or multiple cancers in the family." — Conor Delaney (clinical) [Ep 4 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1472)
- "Genetic diagnosis may change the surgical approach: patients with multiple polyps or significant family history may be better served with subtotal colectomy (ileosigmoid or ileorectal anastomosis) rather than segmental resection." — Conor Delaney (clinical) [Ep 4 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1472)

## Changelog
- Sep 12: 4 items added automatically

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