Comparative outcomes of neuroendocrine tumors in the historically underserved population of Bronx, NY: Montefiore Einstein Comprehensive Cancer Center.

671 Background: Neuroendocrine tumors (NETs) pose different clinical implications based upon age at diagnosis, with regards to early-onset (EO<50yrs) versus late-onset (LO>=50yrs) disease. While primary-tumor resection is crucial for localized NETs, its benefit in metastatic cases without metastasectomy remains uncertain. This study examines variables associated with survival in EO versus LO cases, including primary tumor resection. Methods: A retrospective cohort of 91 patients with gastrointestinal(GI)-NETs were identified as part of an IRB-approved project. Disease-stage (local vs. metastatic), tumor grade (G1-3), 5-year-survival, primary-tumor removal, and race/ethnicity were included in this analysis. Results: Among all patients, 31.9% identified as Hispanic, 33% as non-Hispanic Black, 22% as non-Hispanic White, and 13.1% as other. Among all patients, 79 were classified as G1/G2. Among LO patients, 87.5% (n=63) were G1/G2, among which 46% (n=29) were metastatic. Among EO patients, 84% (n=16) were G1/G2, among which 68.8% (n=11) were metastatic. In the LO group with G1/G2 tumors, 5-year survival rate was 48.3% for metastatic disease and 58.8% for localized disease. For EO with G1/G2 tumors, the 5-year survival rate was 72.7% for metastatic disease and 80% for localized disease. In the EO G1/G2 group, 5 of the 11 patients with metastatic disease had primary tumor removal without metastasectomy with 100% 5-year survival rate. In the LO G1/G2 group, 7 of 29 metastatic patients had primary tumor removal without metastasectomy, with 86% 5-year survival rate. Resection of primary tumor (without metastasectomy) in patients with metastatic G1/G2 NETs was associated with improved 5-year survival, independent of age at diagnosis ( p-value =0.008), as shown in the table. Conclusions: This study helps to emphasize the importance of primary tumor removal in improving survival outcomes for patients with metastatic low-grade GI-NETs, regardless of age. Further investigation is warranted to study the role of certain imperative variables such as site of metastases, number of metastases, and patient co-morbidities. Survival outcomes based on primary tumor removal in metastatic low-grade GI-NETs. No 5-year survival 5-year survival Primary tumor removal without metastasectomy 1 11 No surgery 12 8