Brachytherapy and survival in small cell cancer of the cervix and uterus

Small cell cancer involving the cervix and uterus is considered the same rare disease, but management is controversial and disparate. Patterns of care and outcomes in the United States are unclear.

Clinical data from patients with small cell cancer of the cervix and uterus were abstracted from the National Cancer Database from 2004 to 2014. Patients with missing clinical stage, incomplete followup, or receiving treatment >90 days from diagnosis were excluded.

There were 621 cervical and 95 uterine patients with cancer treated from 2004 to 2014. Compared to patients with a cervix primary site, patients with a uterine primary site were older (median age 64 years vs. 47 years), more likely to present with distant metastatic disease (47% vs. 33%), less likely to receive any pelvic radiation (31% vs. 64%), less likely to receive brachytherapy (3% vs. 27%), more likely to have at least a total hysterectomy (58% vs. 28%), and less likely to receive chemotherapy (74% vs. 88%), all p < 0.05. Brachytherapy was associated with improved overall survival (OS) for patients with locally advanced cervical small cell carcinoma (II-IVA, p = 0.03), but only 38% of patients with Stage II-IVA disease received brachytherapy. For the uterine site, hysterectomy (p = 0.001) and external irradiation (p = 0.03) were associated with improved OS in unadjusted Kaplan-Meier analysis, but only chemotherapy and stage were significantly associated with higher OS in multivariable analysis.

Brachytherapy may improve OS for Stage II-IVA small cell cancer of the cervix but appears underutilized. Brachytherapy was not commonly delivered for uterine primaries.