locally advanced colon cancer · – viability of bowel – location of obstruction – tumor...

Locally Advanced Colon Cancer

Feiran Lou MD. MS. Richmond University Medical Center

Department of Surgery

www.downstatesurgery.org

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



Presenter

Presentation Notes

Dilated, fluid-filled appendix with appendicolith, early acute appendicitis, 12 mm Cecum distended, likely reactive, no abscess, no abdominal adenopathy

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


Presenter

Presentation Notes

The process of colorectal carcinogenesis may involve the accumulation of mutations in both tumor suppressor genes and proto-oncogenes, as well as epigenetic phenomena like DNA hypermethylation or hypomethylation. Inactivation of the APC gene is one of the earliest mutations in sporadic cancers (Familial polyposis). Mutations in other tumor suppressor genes play an important role, like DCC, SMAD2, occurring at later stage of tumor progression. Muations in the K-ras and BRAF oncogenes occurs at an intermediate stage. MSI is an alternative pathway to genomic instability and carcinogenesis


Presenter

Presentation Notes

Most tumors occur in the distal colon but proximal colon ca has been increasing in the last 30 years

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


Presenter

Presentation Notes

Surgical resection is the foundation of curative treatment for localized colon cancer and select patients with limited metastatic disease. 75% patients are candidates for potentially curative surgical resection at the time of diagnosis

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?


Presenter

Presentation Notes

For left sided lesions, the morbidity and mortality appear to be the same when comparing single vs. multi-stage procedures On table colonic lavage was performed because of concerns for performing primary anastomosis in unprepped bowel, it is time consuming and carries additional risk of spillage

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


Presenter

Presentation Notes

Because the final decision for multivisceral resection must be made at the time of laparotomy, the accuracy of assessemtn for potential curability is very important

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


locally advanced colon cancer · – viability of bowel – location of obstruction – tumor...

Documents