Locally Advanced Colon Cancer Feiran Lou MD. MS. Richmond University Medical Center Department of Surgery
Case 34 yo man presented with severe RLQ abdominal pain X 24 hrs. No nausea/vomiting/fever. + flatus. No change in bowel habits. No weight loss. PM/SH: rheumatoid arthritis, never c-scope Meds: methothrexate X 2 years NKDA SH: No toxic habits FH: no hx cancers in immediate family,?gi cancer in grandmother
Case Physical Exam 98, 138/70, 70, 12, 99% NAD Abd: soft, nondistended, right sided tenderness lower > upper, no rebound, no masses DRE: no gross blood, stool in vault, no palpable masses
Case Labs CBC 12.9/10.6/32.8/274 BMP, LFT, coags WNL
OR Findings Dilated right colon Slightly dilated appendix Firm mass in hepatic flexure invading first portion of duodenum frozen adenocarcinoma Surrounding inflammatory changes, lymphadenopathy No liver masses, no peritoneal seeding Procedure Exploratory laparoscopy converted open, appendectomy, ascending to transverse colon bypass
Postoperative Course Uncomplicated, diet advanced D/C home POD 5 Path Hepatic flexure mass: adenocarcinoma, moderate differentiated Appendix: impacted fecalith, dilated distal end, no inflammation
Outline Pathogenesis Surgical Resection Challenges in locally advanced tumors Obstruction Visceral invasion Adjuvant therapy
Colon Cancer Pathogenesis
Staging
Goals of Surgical Treatment Ideally R0 resection Thorough abdominal exploration Completely resect involved colonic segment with 2-5 cm margin En bloc resection of any local structures or organs invaded by the primary tumor Removal of major vascular pedicle and lymphatic drainage basins Minimum of 12 lymph nodes required
Locally Advanced Colon Cancer Obstruction Bypass Stent Invasion of adjacent organs En bloc resection Neoadjuvant therapy (?)
Acute Obstruction Initial presentation in 7-29% of colorectal ca Partial obstruction does not necessitate urgent surgical intervention Complete obstruction Viability of bowel Location of obstruction Tumor resectability Goals of care
Resection Right-sided lesions Single-stage segmental colectomy Left-sided lesions 1 vs. 2 vs. 3-stage procedures Segmental vs. subtotal colectomy Intraoperative colonic lavage?
Palliation Diversion Stoma Bypass Stent Left-sided obstruction Technical success rates 66-100% Luminal patency 68-288 days (106 days) Complications: perforation (2-5%) and migration (4-9%)
Visceral Invasion To achieve R0 resection Multivisceral resection done in 10% of advanced colorectal cancer Most commonly involved organs in colon ca: Small bowel Bladder Abdominal wall Spleen Duodenum, pancreas, stomach
Accuracy of Intraoperative Assessment Tumor infiltration in 34% resected organs
Outcomes Post operative complications 33% Post operative mortality 7.5% Curative resection in 65% Histologic tumor infiltration 44% Overall 5 year survival 51%
Overall Survival
Conventional Vs. Multivisceral Resection
Chemotherapy Neoadjuvant? Pilot trials 5-Fluorouracil with leucovorin Capecitabine: PO prodrug Monoclonal antibodies Bevacizumab, cetuximab, panitumumab (anti- EGFR)
Adjuvant Chemotherapy First line: FOLFOX = 5-FU + LV + oxaliplatin X 6 months Second line: FOLFIRI = 5FU + LV + irinotecan Stage III recurrence 15-50% chemotherapy adjuvant therapy in all Stage II: high risk tumors only perforation, poor tumor differentiation, lymphovascular invasion, insufficient lymph node sampling
Summary Locally advanced colon cancers present unique challenges in surgical treatment Definitive surgery (R0) may require en bloc multivisceral resection Long term survival can be comparable to standard resection After resection, adjuvant chemotherapy in stage III and high risk stage II patients improves survival Role of neoadjuvant chemotherapy remains to be defined
Emergency surgery (n=51) vs. stenting then resection (n=47) Acute malignant left-sided obstruction Lancet oncol 12(4)344-352, 2011