Neuroendocrine carcinoma of the endometrium: Disease course, treatment, and outcomes.

OBJECTIVE

Neuroendocrine carcinoma of the endometrium (NECE) is a rare malignancy. We examined the natural history and outcomes of women with NECE compared to patients with poorly differentiated endometrioid endometrial cancer (EC).

METHODS

The National Cancer Database (NCDB) was used to identify women with NECE and women with poorly differentiated EC from 2004 to 2015. Clinical, demographic, and treatment characteristics were compared between groups. Kaplan-Meier survival curves and multivariable Cox proportional hazard regression models were used to identify associations between tumor histology and survival.

RESULTS

A total of 28,291 women with EC and 364 women with NECE were identified. Patients with NECE were more often non-white and presented with later stage disease compared to patients with EC. Women with NECE were more likely to receive adjuvant chemotherapy (60.2% vs. 29.6%), but were less likely to receive radiation (28.0% vs. 47.6%) (P < 0.001 for both). Median survival was 17 months (95% CI, 12-23) for NECE and 144 months (95% CI, 140-148) for EC. 5-year survival was 38.3% (95% CI, 32.7-43.8%) for NECE vs. 68.8% (95% CI, 68.2-69.4%) for EC. In a multivariable model, the hazard ratio for death for women with NECE compared to EC was 2.32 (95% CI, 1.88-2.88). Similar findings were noted when the analysis was limited to women with stage I (HR = 1.62; 95% CI, 1.01-2.61), and stage III (HR = 2.57; 95% CI, 1.88-3.53) neoplasms.

CONCLUSIONS

NECE is a rare and aggressive uterine carcinoma. Compared to patients with poorly differentiated EC, patients with NECE present with later stage disease and have decreased survival.