06.16 Survival of Rectal Carcinoids by Extent of Surgery: A National Analysis of 1,900 Patients

B. Ezekian1, M. A. Adam1, B. F. Gilmore1, Z. Sun1, M. L. Cox1, M. C. Turner1, C. R. Mantyh1, J. Migaly1  1Duke University Medical Center,Department Of Surgery,Durham, NC, USA

Introduction:
Current National Comprehensive Cancer Network (NCCN) guidelines recommend local resection for rectal carcinoids ≤2 cm and radical resection for tumors >2 cm. However, given the limited data examining the appropriate extent of surgery for these lesions, we queried a national database to determine the impact of extent of resection on pathologic lymph node positivity and survival.

Methods:
Patients undergoing surgical treatment for non-metastatic, clinically-node negative rectal carcinoid were identified from the National Cancer Data Base (1998-2012). The association between extent of surgery, tumor size, and the likelihood of lymph node positivity was examined. Kaplan-Meier analysis was used to compare overall survival between patients undergoing local vs. radical resection.

Results:
In total, 1,900 patients were identified, of whom 1,644 (86.5%) were treated with a local resection and 256 (13.5%) were treated with a radical resection. Patient age, race, co-morbidities, and 30-day mortality were not different between groups (all p > 0.05). A vast majority of patients with tumors ≤2 cm received a local excision (88.96%), whereas most patients with tumors 2.1-4 cm (55.17%) or >4 cm (54.17%) received radical surgery. In patients who underwent radical resection, those with larger tumor size were more likely to have lymph node metastases (7.0% of patients with ≤2 cm tumors, 31.3% with 2.1-4 cm tumors, and 50.0% with >4 cm tumors). 5-year survival was not different in patients receiving local vs. radical surgery for tumors <4 cm (93% vs 93%, p = 0.67 for tumors ≤2 cm and 76% vs. 76%, p = 0.77 for tumors 2.1-4 cm).

Conclusion:
In this large cohort of patients with rectal carcinoids, we show that while survival appears to be equivalent between local vs. radical resection for rectal carcinoids up to 4 cm, the likelihood of lymph node metastases significantly increases with tumor size >2 cm. Thereby, current guidelines recommending radical resection for tumors >2 cm seem appropriate.