Epidemiology and survival outcomes of colorectal mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinoma

• Published in: Surgery Vol. 175; no. 3; pp. 735 - 742
• Main Authors: Suraju, Mohammed O., Freischlag, Kyle, Jacob, Denise, Thompson, Dakota, Mckeen, Andrew, Tran, Catherine, Sherman, Scott K., Goffredo, Paolo, Weigel, Ronald J., Hassan, Imran
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-03-2024
• Subjects: Carcinoma, Neuroendocrine - epidemiology; Carcinoma, Neuroendocrine - pathology; Carcinoma, Neuroendocrine - therapy; Chemotherapy, Adjuvant; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - therapy; Combined Modality Therapy; Humans; Neoplasm Staging; Neuroendocrine Tumors - epidemiology; Neuroendocrine Tumors - pathology; Neuroendocrine Tumors - therapy; Prognosis; Retrospective Studies
• ISSN: 0039-6060; 1532-7361; 1532-7361
• DOI: 10.1016/j.surg.2023.09.019

Mixed neuroendocrine–non-neuroendocrine neoplasms are a rare subtype of neuroendocrine neoplasm consisting of ≥30% each of neuroendocrine and non-neuroendocrine differentiation. Neuroendocrine carcinomas are poorly differentiated neuroendocrine tumors. The epidemiology and prognosis of colorectal mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas are not clearly defined in the literature. We sought to examine the presentation, patterns of care, and outcomes of patients with mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas.
We identified patients diagnosed with stage I–III colorectal (excluding appendix) mixed neuroendocrine–non-neuroendocrine neoplasms or neuroendocrine carcinomas with only one-lifetime cancer diagnosis who underwent surgical resection between 2010 and 2018 from the National Cancer Database. We performed bidirectional selection to identify variables to include in a multivariable Cox proportional hazards model.
We identified 189 patients with a diagnosis of stage I to III colorectal mixed neuroendocrine–non-neuroendocrine neoplasms, 66% of whom had poorly differentiated tumors and 482 with neuroendocrine carcinomas. Among patients with stage III disease, 68% of patients with mixed neuroendocrine–non-neuroendocrine neoplasms and 54% of patients with neuroendocrine carcinomas received adjuvant chemotherapy. The median survival for the overall patients with mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas cohorts were 38 and 42 months, respectively (P = .22), and the median survival for patients with mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas with stage III disease were 30 and 25 months, respectively (P = .27). In multivariable analysis, fewer number of positive nodes and receipt of adjuvant chemotherapy were independently associated with decreased risk of mortality for patients with mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas.
Adjuvant chemotherapy is associated with improved survival in stage III mixed neuroendocrine–non-neuroendocrine neoplasms and neuroendocrine carcinomas. Future studies are warranted to identify subsets of patients benefiting most from adjuvant therapy.