A 58-year-old man from rural Maharashtra presents with a 6-month history of altered bowel habits, alternating constipation and diarrhea, and progressive weight loss of 8 kg. On examination, a palpable mass is felt in the left lower abdomen. Colonoscopy reveals a stenosing lesion at the sigmoid colon with biopsy confirming adenocarcinoma. CT staging shows the tumor invading the muscularis propria with 3 out of 12 regional lymph nodes involved; no distant metastases. The patient is fit for surgery. Which of the following is the most appropriate surgical management?

Explanation

## Clinical Assessment This patient has a **stenosing sigmoid colon cancer** staged as **T2N1M0(Stage IIIA)** — tumor invading muscularis propria, 1–3 regional lymph nodes positive, no distant metastases — with adequate performance status and no acute obstruction. Curative-intent surgery is the standard of care. ### Surgical Anatomy & Technique Selection **Key Point:** The anatomical location of the tumor (sigmoid colon, NOT rectosigmoid junction or rectum) is the critical determinant of the correct surgical procedure. | Feature | Sigmoid Colon Cancer | Rectal / Rectosigmoid Cancer | |---------|---|---| | **Standard resection** | Left hemicolectomy (descending + sigmoid colon) | Anterior resection with TME | | **Vascular ligation** | IMA ligated at/near origin (D3 dissection) | IMA + mesorectal envelope excised | | **TME required?** | **No** — mesorectal excision not applicable above peritoneal reflection | **Yes** — essential for rectal cancers ≤15 cm from anal verge | | **Primary anastomosis** | Safe (descending colon to upper rectum) | Safe if >5 cm from anal verge; defunctioning stoma if low | ### Why Left Hemicolectomy (Option B) Is Correct 1. **Tumor location:** Sigmoid colon — the standard oncological resection is **left hemicolectomy**, removing the descending colon, sigmoid colon, and proximal rectum with adequate margins (≥5 cm distal, ≥10 cm proximal). 2. **Lymphovascular clearance:** Requires high ligation of the inferior mesenteric artery (IMA) at its origin to harvest ≥12 lymph nodes (D3 dissection) — achieved by left hemicolectomy. 3. **Primary anastomosis is safe:** Patient is fit, hemodynamically stable, no acute obstruction, no peritoneal contamination — descending colon to rectum anastomosis carries low leak risk. 4. **Curative intent:** T2N1M0 with no metastases — resection with curative intent is mandatory. **High-Yield (Bailey & Love / Schwartz):** Left hemicolectomy for sigmoid colon cancer = gold standard curative resection. TME is reserved for rectal and rectosigmoid cancers, not pure sigmoid cancers. ### Why NOT the Other Options? - **Option A — Palliative colostomy alone:** Completely inappropriate. Patient is fit, resectable, and has no distant metastases. Curative resection is the goal. - **Option C — Hartmann's procedure:** Indicated for acute obstruction with hemodynamic instability, perforation, or Dukes D (metastatic) disease. This patient is stable and fit — primary anastomosis is safe and preferred. Hartmann's without reversal is essentially palliative. - **Option D — Anterior resection with TME:** TME (total mesorectal excision) is the standard for **rectal and rectosigmoid junction** cancers (within 15 cm of anal verge). The stem clearly states the lesion is in the **sigmoid colon** — TME is anatomically inappropriate here. The mesorectum is not the relevant lymphovascular compartment for sigmoid tumors; the mesosigmoid and IMA territory are. **Clinical Pearl:** The verifier's suggestion of TME for sigmoid cancer reflects a common confusion — TME applies to the rectum and rectosigmoid junction. For a clearly sigmoid lesion, left hemicolectomy with IMA ligation is the oncologically correct procedure per standard surgical oncology texts (Bailey & Love, Schwartz's Principles of Surgery). ## Staging & Adjuvant Therapy **TNM for this case: T2N1M0 → Stage IIIA (AJCC 8th ed.)** - T2: Invasion of muscularis propria - N1: 1–3 regional lymph nodes involved - M0: No distant metastases - **5-year survival ~70–75%** with adjuvant chemotherapy **Key Point:** Adjuvant **FOLFOX** (5-FU/leucovorin + oxaliplatin) is the standard of care for Stage III colorectal cancer to reduce recurrence risk and improve overall survival (MOSAIC trial).