Small Cell and Other Rare Histologic Types of Cervical Cancer

PURPOSE OF REVIEW

The goal of this paper was to summarize the recent evidence on rare subtypes of cervical cancer including small-cell carcinoma of the cervix (SCCC), gastric-type adenocarcinoma, and carcinosarcoma.

RECENT FINDINGS

All three cervical cancer subtypes are aggressive with poor treatment response and high recurrence rates. Molecular studies have identified various actionable mutations in both SCCC (PIK3CA, MYC, TP53, PTEN, ARID1A, KRAS, BRCA2) and gastric-type adenocarcinoma (KRAS, ARID1A, PTEN). While there are a limited number of case reports demonstrating a favorable response for recurrent SCCC to immune checkpoint inhibitors, a larger case series failed to show benefit. The checkpoint inhibitors role in gastric-type adenocarcinoma and carcinosarcoma is yet to be determined. Ninety-one percent of SCCC cases show PARP expression, suggesting a possible role for PARP inhibitors; however, this has yet to be examined in future clinical trials. More studies are needed, with a focus on targeted therapies. The role of PARP inhibitors in SCCC is potentially promising, but significant collaboration between centers/groups will be required to achieve this.

The local treatment modalities in FIGO stage I-II small-cell carcinoma of the cervix are determined by disease stage and lymph node status

The purpose of this study was to identify the optimal local treatment modalities for International Federation of Gynecology and Obstetrics (FIGO) stage I-II small-cell carcinoma of the cervix (SCCC), including cancer-directed surgery (CDS) and/or radiotherapy (RT). The Surveillance Epidemiology and End Results (SEER) database was used to identify SCCC patients from 1988 to 2012, and analyzed using Kaplan-Meier survival and Cox regression proportional hazard methods to determine factors significant for cause-specific survival (CSS) and overall (OS). A total of 208 patients of SCCC were enrolled. The median follow-up time was 31 months. Fifty-eight (27.9%) patients were treated with primary CDS, 88 (42.3%) patients underwent CDS combined with RT, and 62 (29.8%) patients were treated with primary RT. Univariate and multivariate analyses showed that local treatment modalities were independent prognostic factors for CSS and OS. Patients who had undergone CDS had better CSS and OS, compared with patients who had been treated with combined CDS and RT or RT alone. The 5-year CSS and OS of entire group was 49.8% and 46.4%, respectively. The 5-year CSS in the groups of patients receiving CDS, CDS combined with RT, and RT alone were 67.9%, 49.7%, and 32.6%, respectively (P < 0.001). The 5-year OS in patients treated with CDS, CDS combined with RT, and RT alone were 64.9%, 46.2%, and 28.8% (P < 0.001). Primary surgery was associated with improved CSS and OS for FIGO stage I and lymph node negative disease. Primary surgery is the most effective local treatment for FIGO stage I-II SCCC, as adjuvant RT or radical RT does not improve survival compared to radical surgery, especially in patients with FIGO stage I and lymph node negative disease.