What is the plan for resection in a patient with multiple linear deep ulcerations on colonoscopy diagnosed with colorectal (colon) cancer?

From the Guidelines

The plan for resection of colon cancer with multiple linear deep ulcerations found on colonoscopy should involve a wide resection of the involved segment of bowel together with the removal of its lymphatic drainage, with at least 12 lymph nodes resected to clearly define stage II versus III and to identify and eradicate potential lymph node metastases. The extent of the colonic resection is determined by the blood supply and distribution of regional lymph nodes, and the resection should include a segment of colon of at least 5 cm on either side of the tumour 1. Key considerations in planning the resection include:

• The location of the tumor, which will guide the choice of surgical procedure such as right or left hemicolectomy, sigmoid colectomy, or total colectomy
• The use of a laparoscopic approach, which can be safely carried out for colon cancer, particularly for left-sided cancer, and offers advantages such as reduced pain, reduced length of hospital stay, and reduced duration of ileus 1
• The importance of complete staging workup prior to surgery, including CT scans of the chest, abdomen, and pelvis to assess for metastatic disease
• The goal of achieving a complete removal of the tumor with negative margins (R0 resection) and adequate lymph node sampling
• The potential need for neoadjuvant chemotherapy or chemoradiation for locally advanced tumors, and adjuvant chemotherapy for stage III disease and high-risk stage II disease. It is crucial that the surgical approach is tailored to the individual patient's needs and that the procedure is performed by technically experienced surgeons 1.

From the Research

Plan of Resection for Colon Cancer

The plan of resection for colon cancer involves several factors, including the location and extent of the tumor, as well as the patient's overall health.

• For patients with multiple linear deep ulceration on colonoscopy diagnosed as colon cancer, the plan of resection may involve a right hemicolectomy or a complete mesocolic excision (CME) depending on the location of the tumor 2.
• A study published in 2013 found that neoadjuvant chemotherapy may have a role in the management of colonic carcinoma, but clinical trials are required to determine whether this approach is superior to the standard policy of radical surgery, high-quality histopathology, and selective postoperative chemotherapy 3.
• The accuracy of preoperative CT scans in predicting postoperative pathology is limited, with sensitivity, specificity, positive predictive value, and negative predictive value of 90,33,86, and 43% respectively for tumor (T) stage, and 83,38,57, and 69% respectively for nodal (N) stage 3.
• Another study published in 2019 found that CT scans have limited accuracy in predicting unfavorable pathologic features, such as T3/4, N+, or extramural venous invasion, with an overall accuracy of 63% 4.
• Complete mesocolic excision (CME) has been shown to improve oncological outcomes without increasing mortality and morbidity rates compared to standard right-side hemicolectomy 2.

Diagnostic Tools

• CT scans are commonly used for staging colon cancer, but their accuracy is limited, and they may not be able to identify all patients with advanced locoregional disease who might benefit from neoadjuvant treatment 3, 4.
• PET/CT may be used in certain scenarios, such as at disease presentation in case of suspected or proven metastatic synchronous adenocarcinoma, or in the workup of recurrent colon cancer with metachronous metastases documented by CT, MRI, or biopsy 5.
• Colonoscopy is an essential diagnostic tool for colon cancer, but it may not always provide a clear diagnosis, especially in cases of signet ring cell carcinoma, which can present with nonspecific findings such as diffuse circumferential thickening, stricture, and ulcerations 6.