Table 2.

Rectal cancer: Precancerous lesions and invasive cancer: assessment and management.

Topic	NCCN a Recommendations	ESMO b Recommendations	JSCCR c Recommendations
Polyp with Invasive Cancer
Assessment	Pathology review Colonoscopy Marking of the polyp site MMR/MSI testing	Biopsy Palpation Rigid sigmoidoscopy (flexible endoscopy) Haggitt’s subclassification (if stalked adenoma) Kikuchi (sm) system (if sessile adenoma) ERUS, MRI	Information on size, predicted depth of invasion, and morphology of the tumour
Management	Observe (pedunculated polyp) or transanal local excision or transabdominal resection (sessile polyp or if incomplete excision)	Haggitt 1–3, T1 sm1 N0: Local procedure, e.g., transanal endoscopic microsurgery (TEM) Haggitt 4, T1 sm ≥2, high-grade, VI: Radical standard surgery (TME), chemoradiotherapy (if surgery contraindicated) Local radiotherapy as an alternative to local surgery, alone or with (preoperative) chemoradiotherapy	Intramucosal (cTis) or carcinoma with slight submucosal invasion (cT1): Pedunculated: endoscopic polypectomy—up to 2 cm in size Sessile: endoscopic mucosal resection (EMR) or using a cap (EMRC)—up to 2 cm size Endoscopic submucosal dissection (ESD) T1b (depth of Sm invasion ≥1000 μm), lymphovascular invasion positive poorly differentiated, signet-ring cell or mucinous carcinoma, Grade 2/3 budding at the site of deepest invasion: Surgical resection (TME)
Resectable rectal cancer
Assessment	Pathology review Colonoscopy CEA levels Chest CT and abdominal CT or MRI Pelvic MRI or ERUS (if MRI is contraindicated, inconclusive, or for superficial lesions) MDT discussion	History Physical exam including DRE Bloods with CEA CT chest-abdomen Rigid sigmoidoscopy Preoperative colonoscopy Virtual colonoscopy in case of obstruction Pelvic MRI ERUS in early cT stage PET-CT if extensive EMVI for other sites MDT discussion	Not formally stated
Management	Transanal local excision if appropriate (T1N0) or transabdominal resection (T1-2N0) Total Neoadjuvant Therapy followed by transabdominal resection vs Long-course CRT or SCRT followed by transabdominal resection followed by adjuvant chemotherapy	Very early cT1N0 with low grade G1/G2: → Local excision e.g., TEM → Local RT as an alternative to local excision alone, or combined with CRT Early, not suitable for local excision, T1–2; cT3a (b) if middle or high, N0 (or cN1 if high), -MRF clear, no EMVI: → surgery (TME) alone Intermediate/more locally advanced cT3a/b (very low, levators clear, MRF clear) or cT3a/b (mid or high rectum, cN1-2, no EMVI): → surgery (TME) alone or preoperative RT (CRT or SCPRT) if good quality mesorectal excision cannot be achieved Locally advanced (>cT3b and EMVI+): → surgery (TME) → preoperative RT (CRT or SCPRT)	Tis and cT1: local excision if lesion located distal to the second Houston valve (peritoneal reflection) Extent of lymphadenectomy (D0–D3) varies with stage (depth of invasion and extent of lymph node metastases) TME or tumour-specific mesorectal excision (TSME) Lateral lymph node dissection is indicated when the lower border of the tumour is located distal to the peritoneal reflection and the tumour has invaded beyond the muscularis propria

Adapted with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines^®) for Guideline Colon Cancer V.1.2022. © 2022 National Comprehensive Cancer Network, Inc. All rights reserved. The NCCN Guidelines^® and illustrations herein may not be reproduced in any form for any purpose without the express written permission of NCCN. To view the most recent and complete version of the NCCN Guidelines, go online to NCCN.org. The NCCN Guidelines are a work in progress that may be refined as often as new significant data become available; EMR = endoscopic mucosal resection; ESD = endoscopic submucosal dissection; CEA = carcinoembryonic antigen; MMR = mismatch repair; MSI = microsatellite instability; 5FU = 5-fluorouracil; RT = radiotherapy; ^a NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines^®) [13]; ^b European Society of Medical Oncology (ESMO) guidelines [15]; ^c Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines [18].