# Colon Cancer — GCMD Library living collection

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

Updated: n/a · 4 episodes · 121 cited statements

## Episodes
### In-Depth Reviews
- [Colon Cancer with Conor Delaney](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443) — podcast · 26:50 · [machine version](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443.md)
- [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/colon-cancer-with-conor-delaney-3443?t=0) Introduction and Serrated Adenomas in Colonoscopy (Ep 1)
- [3:03](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=183) Rectal Cancer Location and Surgical Margins (Ep 1)
- [7:00](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=420) Rectal Cancer Staging with MRI and Circumferential Resection Margin (Ep 1)
- [11:33](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=693) Neoadjuvant Therapy Indications and Transanal Resection (Ep 1)
- [15:58](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=958) ESD vs Full-Thickness Excision for Rectal Lesions (Ep 1)
- [17:18](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1038) Sigmoid and Colon Cancer Surgical Principles (Ep 1)
- [21:22](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1282) Right Hemicolectomy Technique and Anastomosis (Ep 1)
- [24:12](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1452) Genetic Assessment and Hereditary Cancer Syndromes (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 (Ep 2)
- [4:16](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=256) Rectal Cancer Staging and Margins (Ep 2)
- [9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543) MRI Staging and Circumferential Margins (Ep 2)
- [14:06](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=846) Transanal Resection Considerations (Ep 2)
- [17:18](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1038) Neoadjuvant Radiation Protocols (Ep 2)
- [19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162) Sigmoid and Left Colon Resection Technique (Ep 2)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1349) Right Colon and Cecal Cancer Resection (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 Role of Colonoscopy (Ep 3)
- [2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=123) Serrated Polyps and Advanced Polypectomy (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 and Imaging (Ep 3)
- [14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847) Transanal Resection and T1 Tumors (Ep 3)
- [16:58](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1018) Neoadjuvant Radiation Therapy (Ep 3)
- [19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162) Sigmoid Colon Cancer Surgery (Ep 3)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1349) Right Colon Cancer Surgery (Ep 3)
- [24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1453) Genetic Assessment in Colorectal Cancer (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 polyps and advanced polypectomy (Ep 4)
- [4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=299) Rectal cancer: location and surgical margins (Ep 4)
- [9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543) Rectal cancer staging and neoadjuvant therapy (Ep 4)
- [14:18](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=858) Transanal resection and T1 tumors (Ep 4)
- [17:18](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1038) Radiation therapy protocols (Ep 4)
- [19:28](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1168) Sigmoid and left colon cancer surgery (Ep 4)
- [22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1349) Right colon cancer surgery (Ep 4)
- [24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1453) Genetic assessment and hereditary syndromes (Ep 4)

## Statements
Every statement is attributed, typed, and timestamped; the link is the citation.
- "Colonoscopy is still the best test 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 have good evidence of genetic predisposition and may 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 really high risk of cancer" — Conor Delaney (clinical) [Ep 2 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=123)
- "Some serrated polyps are flat and difficult to see, making retroflexion in the cecum useful as they're often on the inferior or superior side of the valve" — Conor Delaney (clinical) [Ep 2 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=206)
- "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)
- "Current local recurrence rates should be under 10 percent, with Cleveland Clinic's last 10 years at about 3 percent" — Conor Delaney (epidemiological) [Ep 2 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=543)
- "Distal margin requirements for rectal cancer: 5 centimeters if possible, 2 centimeters if possible, and for very lowest tumors perhaps 1 centimeter as long as they're 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 probably high 80s to 90% accurate for nodal staging" — Conor Delaney (clinical) [Ep 2 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=791)
- "Ultrasound is much more operator dependent and probably only 70% accurate for predicting nodal involvement" — Conor Delaney (clinical) [Ep 2 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=791)
- "The standard of care has shifted from ultrasound to MRI for rectal cancer staging" — Conor Delaney (guideline) [Ep 2 · 14:02](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=842)
- "Historical local recurrence rates for transanally excised rectal cancers was about 18%, remarkably consistent across outcome data from several big centers" — Conor Delaney (epidemiological) [Ep 2 · 14:19](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=859)
- "Transanal resection is generally kept for patients who aren't fit for a rectal resection, or patients whose tumor is so close to the dentate line you'd have to give them a permanent stoma" — Conor Delaney (guideline) [Ep 2 · 14:19](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=859)
- "If it's a rectal cancer, it needs to be a full thickness excision; you would never do an ESD type procedure" — Conor Delaney (guideline) [Ep 2 · 16:23](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=983)
- "Neoadjuvant therapy is generally indicated for T3 or node-positive disease" — Conor Delaney (guideline) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "In Europe, radiation has gone towards five times five gray given over five days, with surgery about a week to two weeks later" — Conor Delaney (guideline) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "In the US, radiation is six-week, 40 to 45 gray, given with chemotherapy, staged over six weeks, then a six-week to eight-week waiting period" — Conor Delaney (guideline) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "25 gray over a short period is equivalent to 40 to 45 over a longer period from a radiotherapeutic perspective" — Conor Delaney (clinical) [Ep 2 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1045)
- "For colon cancer surgery, you're looking for at least a five centimeter proximal and distal margin, usually determined by blood supply, and at least 12 lymph nodes, with many hoping for at least 16" — Conor Delaney (guideline) [Ep 2 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162)
- "You should be able to do a total mesocolic excision with five mils of blood loss, in the plane between Toltz fascia and the embryological peritoneum on the mesocolon" — Conor Delaney (clinical) [Ep 2 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1162)
- "Scandinavian data showed local recurrence rate for colon cancer was even higher than their rectal cancer local recurrence rate because 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, you should take 10 centimeters of small bowel; if it's mid-ascending colon, you should take 5" — Conor Delaney (guideline) [Ep 2 · 22:44](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1364)
- "Extracorporeal stapled anastomosis for laparoscopic right colectomy has reported leak rates of 0.8% over 1,000 cases" — Conor Delaney (epidemiological) [Ep 2 · 23:59](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1439)
- "The Weiss Center for Hereditary Colorectal Cancer has the biggest polyposis database in the world and probably now the biggest HNPCC database as well" — Conor Delaney (clinical) [Ep 2 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13749?t=1472)
- "Colonoscopy is still the best test for colon cancer detection, though not perfect, finding the vast majority of cancers and polyps" — Conor Delaney (clinical) [Ep 3 · 1:15](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=75)
- "Serrated adenomas (previously called hyperplastic polyps in right colon) 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" — 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, requiring retroflexion in the cecum to visualize them on the inferior or superior side of the valve or folds" — Conor Delaney (clinical) [Ep 3 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=206)
- "Required distal margin for rectal cancer is 5 centimeters if achievable, 2 centimeters if achievable, and for very lowest tumors perhaps 1 centimeter as long as they are not poorly differentiated" — Conor Delaney (clinical) [Ep 3 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=299)
- "Six centimeters from anal verge in an 80-year-old 90-pound female can be almost mid-rectum, while in a 6'6" 300-pound male can be top of anal canal or close to dentate line" — Conor Delaney (clinical) [Ep 3 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=299)
- "Upper third rectal cancers likely will not need preoperative therapy and likely will not need a stoma" — Conor Delaney (clinical) [Ep 3 · 6:51](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=411)
- "Middle and lower third rectal cancers have good chance of needing preoperative neoadjuvant therapy and very good chance of needing temporary or rarely permanent stoma" — Conor Delaney (clinical) [Ep 3 · 6:51](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=411)
- "Distant staging for rectal cancer is best with CT abdomen for liver and most guidelines have transitioned to CT chest rather than chest x-ray" — Conor Delaney (guideline) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Majority of local staging has transitioned to MRI with high resolution, high Tesla magnet standardized protocol" — Conor Delaney (guideline) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "MRI is particularly good at distinguishing T3, T4 and particularly good at looking at circumferential resection margins" — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Historical local recurrence rates for rectal cancer from good institutions were 20 to 38 percent and some up to 50 percent" — Conor Delaney (epidemiological) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Current local recurrence rates should be under 10 percent, and Cleveland Clinic's last 10 years was about 3 percent with optimized surgery, imaging, and patient selection" — Conor Delaney (epidemiological) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "MRI is the best way to assess circumferential resection margin" — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Endoscopic ultrasound can be used selectively for distinguishing T1s and T2s for potential transanal resection but does not assess circumferential resection margin" — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "Total mesorectal excision can be performed with about 5 mils of blood loss because it is a bloodless plane" — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "If pathological margin is negative, chance of local recurrence is low" — Conor Delaney (clinical) [Ep 3 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=543)
- "MRI is probably 90 to mid-90s percent accurate at T staging and probably high 80s to 90 percent accurate for nodal staging" — Conor Delaney (clinical) [Ep 3 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=798)
- "Ultrasound is much more operator dependent and probably only 70 percent accurate for predicting nodal involvement" — Conor Delaney (clinical) [Ep 3 · 13:18](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=798)
- "Transanal resection is appropriate for tumors less than a third of circumference, ideally less than two centimeters, that are T1" — Conor Delaney (clinical) [Ep 3 · 14:07](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=847)
- "Historical local recurrence rates for transanally excised rectal cancers was about 18 percent, 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)
- "For rectal cancer, full thickness excision is required; ESD type procedure would never be done for cancer" — Conor Delaney (clinical) [Ep 3 · 15:58](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=958)
- "Most accepted guidelines for neoadjuvant therapy are for tumors that are T3 (outside wall of rectum) or node positive" — Conor Delaney (guideline) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "If node negative and T1 or T2 (stage one tumor), 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)
- "In Europe, short course radiation is five times five gray given over five days, then operate about one to two weeks later" — Conor Delaney (clinical) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "In US, long course is six-week 40 to 45 gray given with chemotherapy staged over six weeks, then six to eight week waiting period" — Conor Delaney (clinical) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "25 gray over short period is equivalent dose to 40 to 45 over longer period from radiotherapeutic perspective" — Conor Delaney (clinical) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "Longer course chemoradiation can make big difference for tumor response and physical downstaging, particularly for bulky tumors" — Conor Delaney (clinical) [Ep 3 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1045)
- "For colon cancer, need at least five centimeter proximal and distal margin, usually determined by blood supply, and at least 12 lymph nodes, ideally at least 16" — Conor Delaney (clinical) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "For sigmoid cancer, most surgeons do high ligation above takeoff of left colic artery" — Conor Delaney (clinical) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "Total mesocolic excision should be achievable with five mils of blood loss, dissecting between embryological peritoneum of retroperitoneum (Toltz fascia) and embryological peritoneum on mesocolon" — 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 rectal cancer rates (which were high 20s) because they were not doing adequate colon cancer surgery" — Conor Delaney (epidemiological) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "After focusing on technique, Scandinavian centers got rectal cancer local recurrence rate down to under 10 percent" — Conor Delaney (epidemiological) [Ep 3 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1162)
- "For cecal tumor or near ileocecal valve, should take 10 centimeters of small bowel; if mid-ascending colon, should take 5 centimeters" — Conor Delaney (clinical) [Ep 3 · 22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1349)
- "Extracorporeal stapled anastomosis for right colectomy has reported leak rates of 0.8 percent over 1,000 cases" — Conor Delaney (epidemiological) [Ep 3 · 22:29](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1349)
- "Cleveland Clinic has biggest polyposis database in world and probably biggest HNPCC database as well through Weiss Center for Hereditary Colorectal Cancer" — Conor Delaney (epidemiological) [Ep 3 · 24:13](https://library.globalcastmd.com/watch/colorectal-cancer-13750?t=1453)
- "Colonoscopy is still the best test for colon cancer detection, though not perfect—it doesn't find every cancer or polyp but finds the vast majority" — Conor Delaney (clinical) [Ep 4 · 1:15](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=75)
- "Serrated adenomas (previously called hyperplastic polyps in right colon) have good evidence of genetic predisposition and tie into many family cancer syndromes" — Conor Delaney (clinical) [Ep 4 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=123)
- "Serrated polyps have a very high risk of cancer" — Conor Delaney (clinical) [Ep 4 · 2:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=123)
- "Serrated adenomas are often flat and difficult to see; retroflexion in the cecum is useful because they're often on the inferior or superior side of the valve or folds" — Conor Delaney (clinical) [Ep 4 · 3:26](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=206)
- "Distal margin requirements for rectal cancer: 5cm if possible, 2cm if possible, 1cm for very lowest tumors as long as not poorly differentiated" — Conor Delaney (clinical) [Ep 4 · 6:28](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=388)
- "Six centimeters from anal verge can mean different anatomical locations: may be anorectal ring or close to dentate line in a large person, requiring different surgical approaches" — Conor Delaney (clinical) [Ep 4 · 4:59](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=299)
- "Historical local recurrence rates for rectal cancer from good institutions were 20-38% and some up to 50%; nowadays should be under 10%, and Cleveland Clinic's last 10 years was about 3%" — Conor Delaney (epidemiological) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "MRI is the best way to assess circumferential resection margin in rectal cancer" — Conor Delaney (clinical) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "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 4 · 13:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=812)
- "Endoscopic ultrasound is much more operator dependent and probably only 70% accurate for predicting nodal involvement" — Conor Delaney (clinical) [Ep 4 · 13:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=812)
- "Standard of care has shifted from ultrasound to MRI for rectal cancer staging" — Jeffrey Ponsky (guideline) [Ep 4 · 14:06](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=846)
- "Historical local recurrence rates for transanally excised rectal cancers was about 18%, remarkably consistent across outcome data from several big centers" — Conor Delaney (epidemiological) [Ep 4 · 14:19](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=859)
- "For rectal cancer, if doing transanal resection even for T1, must do full thickness resection, never ESD; ESD or EMR is only for benign polyps" — Conor Delaney (clinical) [Ep 4 · 16:23](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=983)
- "Neoadjuvant therapy for rectal cancer is generally indicated for T3 or node-positive disease" — Conor Delaney (guideline) [Ep 4 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1045)
- "Threatened circumferential resection margin (wanting 1-2mm) is an indication for neoadjuvant therapy" — Conor Delaney (clinical) [Ep 4 · 17:25](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1045)
- "Short-course radiation is 5 times 5 gray over 5 days, then operate 1-2 weeks later (European approach)" — Conor Delaney (clinical) [Ep 4 · 17:18](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1038)
- "Long-course chemoradiation is 40-45 gray over 6 weeks with chemotherapy, then 6-8 week waiting period (US approach)" — Conor Delaney (clinical) [Ep 4 · 17:18](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1038)
- "25 gray over short period is equivalent dose to 40-45 gray over longer period, but longer course better for tumor response and physical downstaging of bulky tumors" — Conor Delaney (clinical) [Ep 4 · 17:18](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1038)
- "For colon cancer surgery, looking for at least 12 lymph nodes, many would hope for at least 16" — Conor Delaney (clinical) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "Total mesorectal excision can be done with about 5 mils of blood loss because it's a bloodless plane; if there's bleeding, you're in the wrong plane unless deliberately outside" — Conor Delaney (clinical) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "Total mesocolic excision should be done with 5 mils of blood loss, in the plane between embryological peritoneum of retroperitoneum (Toltz fascia) and embryological peritoneum on mesocolon" — Conor Delaney (clinical) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "Scandinavian data showed local recurrence rate for colon cancer was even higher than rectal cancer (high 20s%) because they weren't doing adequate colon cancer surgery" — Conor Delaney (epidemiological) [Ep 4 · 19:22](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1162)
- "For cecal or ileocecal valve tumors, should take 10 centimeters of small bowel; if mid-ascending colon, should take 5cm" — Conor Delaney (clinical) [Ep 4 · 22:44](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1364)
- "Extracorporeal stapled anastomosis for right hemicolectomy has reported leak rates of 0.8% over 1,000 cases" — Conor Delaney (epidemiological) [Ep 4 · 23:59](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1439)
- "If negative pathological margin achieved in rectal cancer surgery, chance of local recurrence is low" — Conor Delaney (clinical) [Ep 4 · 9:03](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=543)
- "Transanal resection criteria: generally tumors less than 1/3 circumference, ideally less than 2cm, that are T1" — Conor Delaney (clinical) [Ep 4 · 14:19](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=859)
- "For most young curable patients, people tend to favor radical resection over transanal resection; transanal kept for patients unfit for rectal resection or tumor so close to dentate line would require permanent stoma" — Conor Delaney (opinion) [Ep 4 · 14:19](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=859)
- "Node negative and T1 or T2 (stage one tumor), particularly if upper third rectum, can omit neoadjuvant radiation" — Conor Delaney (guideline) [Ep 4 · 13:11](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=791)
- "Indications for genetic workup: any risk of Bethesda criteria, first degree relatives, somebody young in family, cancer under 40, multiple cancers in family, non-GI cancers in family" — Conor Delaney (guideline) [Ep 4 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1472)
- "Genetic assessment may change the operation: if right colon cancer with multiple polyps or significant history, maybe better with subtotal colectomy; if familial polyposis, maybe proctocolectomy" — Conor Delaney (clinical) [Ep 4 · 24:32](https://library.globalcastmd.com/watch/colorectal-cancer-13754?t=1472)
- "Colonoscopy is still the best test for colon cancer detection, finding the vast majority of cancers and polyps, though not perfect." — Conor Delaney (clinical) [Ep 1 · 1:16](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=76)
- "Serrated adenomas (previously misclassified as hyperplastic polyps, particularly large ones in the right colon) have genetic predisposition, tie into family cancer syndromes, and carry very high cancer risk." — Conor Delaney (clinical) [Ep 1 · 2:05](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=125)
- "Finding serrated adenomas requires family assessment for hereditary cancer syndromes and may necessitate changes in colonoscopy frequency and family member screening." — Conor Delaney (guideline) [Ep 1 · 2:42](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=162)
- "Serrated polyps can be flat and difficult to visualize; retroflexion in the cecum is increasingly used because they are often on the inferior or superior side of folds." — Conor Delaney (clinical) [Ep 1 · 3:27](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=207)
- "For rectal cancer, distal margin requirements are 5 cm if achievable, 2 cm if necessary, and 1 cm for very low tumors as long as they are not poorly differentiated." — Conor Delaney (clinical) [Ep 1 · 6:13](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=373)
- "The measurement '6 centimeters from the anal verge' varies significantly by patient body habitus and can represent different anatomical locations (anorectal ring vs. near dentate line)." — Conor Delaney (clinical) [Ep 1 · 7:25](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=445)
- "Distant staging for rectal cancer is best performed with CT abdomen (for liver metastases) and CT chest (replacing chest X-ray per current guidelines)." — Conor Delaney (guideline) [Ep 1 · 9:31](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=571)
- "MRI has become the standard for local staging of rectal cancer, with high-resolution, high-Tesla magnets using standardized protocols developed by Bill Heald and Gina Brown at the Royal Marsden." — Conor Delaney (clinical) [Ep 1 · 9:50](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=590)
- "MRI is 90 to mid-90s percent accurate for T-staging and high 80s to 90% accurate for nodal staging of rectal cancer." — Conor Delaney (clinical) [Ep 1 · 13:37](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=817)
- "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 1 · 13:56](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=836)
- "MRI is particularly good at distinguishing T3 and T4 tumors and assessing circumferential resection margins, though less accurate at distinguishing T1 from T2." — Conor Delaney (clinical) [Ep 1 · 10:27](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=627)
- "Historical local recurrence rates for rectal cancer from good institutions were 20–38%, with some series up to 50%." — Conor Delaney (epidemiological) [Ep 1 · 10:51](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=651)
- "With optimized surgery and imaging, local recurrence rates for rectal cancer should now be under 10%; Cleveland Clinic's rate over the last 10 years was about 3%." — Conor Delaney (epidemiological) [Ep 1 · 11:04](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=664)
- "Circumferential resection margin is the most important margin (or many think more important than distal margin) for preventing local recurrence in rectal cancer." — Conor Delaney (clinical) [Ep 1 · 10:39](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=639)
- "Total mesorectal excision (TME) can be performed with about 5 mL of blood loss because it follows a bloodless embryological plane; bleeding indicates wrong plane unless deliberately outside TME plane." — Conor Delaney (clinical) [Ep 1 · 12:24](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=744)
- "Neoadjuvant therapy for rectal cancer is indicated for T3 tumors (outside the rectal wall) or node-positive disease." — Conor Delaney (guideline) [Ep 1 · 12:54](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=774)
- "Stage 1 rectal cancer (node-negative, T1 or T2), particularly in the upper third of the rectum, does not require neoadjuvant therapy." — Conor Delaney (guideline) [Ep 1 · 13:18](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=798)
- "Short-course radiation (5×5 Gy over 5 days, surgery 1–2 weeks later) is commonly used in Europe; long-course chemoradiation (40–45 Gy over 6 weeks with 6–8 week wait) is standard in the US." — Conor Delaney (guideline) [Ep 1 · 18:04](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1084)
- "25 Gy over a short period is radiotherapeutically equivalent to 40–45 Gy over a longer period, but long-course therapy may produce better tumor downstaging for bulky tumors." — Conor Delaney (clinical) [Ep 1 · 18:26](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1106)
- "Transanal resection for rectal cancer is generally limited to T1 tumors less than one-third circumference and ideally less than 2 cm." — Conor Delaney (guideline) [Ep 1 · 14:35](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=875)
- "Historical local recurrence rates for transanally excised rectal cancers were about 18%, remarkably consistent across multiple centers." — Conor Delaney (epidemiological) [Ep 1 · 14:51](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=891)
- "Transanal endoscopic microsurgery (TEM) may produce better outcomes than traditional transanal excision, though it is unclear whether this is due to technology or improved surgical understanding." — Conor Delaney (opinion) [Ep 1 · 15:05](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=905)
- "For young, curable patients, radical resection is generally favored over transanal resection; transanal resection is typically reserved for patients unfit for radical surgery or those who would require permanent stoma." — Conor Delaney (guideline) [Ep 1 · 15:27](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=927)
- "For rectal cancer, full-thickness excision is required; ESD or EMR is never appropriate for proven cancer, only for benign polyps." — Conor Delaney (clinical) [Ep 1 · 16:24](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=984)
- "For colon cancer, at least 12 lymph nodes are required for adequate staging, though many surgeons aim for at least 16." — Conor Delaney (guideline) [Ep 1 · 19:51](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1191)
- "High ligation of the inferior mesenteric artery (above the takeoff of the left colic artery) is standard for sigmoid colectomy, with protection of autonomic nerves to preserve sexual function." — Conor Delaney (clinical) [Ep 1 · 19:59](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1199)
- "Total mesocolic excision for colon cancer should be performed with about 5 mL of blood loss in the embryological plane between retroperitoneal peritoneum (Toldt's fascia) and mesocolic peritoneum." — Conor Delaney (clinical) [Ep 1 · 20:18](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1218)
- "Scandinavian data showed local recurrence rates for colon cancer were even higher than for rectal cancer (high 20s%) before focus on complete mesocolic excision technique." — Conor Delaney (epidemiological) [Ep 1 · 20:48](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1248)
- "For cecal or ileocecal valve tumors, 10 cm of small bowel should be resected; for mid-ascending colon tumors, 5 cm of small bowel is adequate." — Conor Delaney (clinical) [Ep 1 · 23:12](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1392)
- "Extracorporeal stapled anastomosis for right hemicolectomy achieved a leak rate of 0.8% over 1000 cases at Cleveland Clinic." — Conor Delaney (epidemiological) [Ep 1 · 24:00](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1440)
- "Genetic assessment is indicated for colorectal cancer patients with Bethesda criteria risk factors, cancer under age 40, first-degree relatives with cancer, or multiple cancers in the family." — Conor Delaney (guideline) [Ep 1 · 24:56](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1496)
- "Genetic diagnosis affects both family screening recommendations and surgical approach; patients with hereditary syndromes may require subtotal colectomy or proctocolectomy rather than segmental resection." — Conor Delaney (clinical) [Ep 1 · 25:33](https://library.globalcastmd.com/watch/colon-cancer-with-conor-delaney-3443?t=1533)

## Changelog
- Sep 7: 4 items added automatically

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