Significance of definitive concurrent chemoradiotherapy for vulvar cancer: a Japanese Gynecologic Oncology Group nationwide survey study

TL;DR

This study shows that combining chemotherapy with radiation improves survival for stage III vulvar cancer patients in Japan.

Contribution

The study demonstrates the survival benefit of concurrent chemoradiotherapy specifically for stage III vulvar cancer.

Findings

Stage III patients receiving CCRT had significantly better 2-year survival than those with RT alone.

Tumor diameter, lymph node status, and treatment type were significant prognostic factors for survival.

Multivariate analysis confirmed chemotherapy's benefit in stage III disease.

Abstract

This study aimed to show the results of radical radiation therapy (RT) and concurrent chemoradiotherapy (CCRT) for vulvar cancer (VC) based on data from a Japanese nationwide survey.

We collected data from 108 institutions on cases of VC diagnosed between January 2001 and December 2010. Patients with histologically proven squamous cell carcinoma and adenocarcinoma with curative intent were selected, and 172 patients with VC were included in this study. The collected data were analyzed for overall survival (OS) using the Kaplan–Meier method. Univariate and multivariate analyses were performed to examine the prognostic factors for patients with VC.

The median follow-up period was 16.8 (range; 3.2–154.8) months. Fifty-five patients received CCRT, and 117 patients received RT alone. The 2-year OS rates (95% confidence interval [CI]) for stages I, II, III, and IV were 77.9% (55.8–100.0), 71.9% (53.8–89.9), 55.4% (42.5–68.3), and 41.5% (27.3–55.7) respectively. Univariate analyses showed that the FIGO stage (p = 0.001), tumor diameter (p = 0.005), and lymph node (LN) status (p = 0.001) were associated with OS. The concurrent use of chemotherapy resulted in a significantly longer OS in Stage III (p = 0.013). Multivariate analysis showed that the hazard ratios (95% CI) for tumor diameter, positivity for LN metastasis, and RT alone (no concurrent chemotherapy) were 1.502 (1.116–2.021), 1.801 (1.287–2.521), and 1.936 (1.187–3.159), respectively.

Our analysis revealed that CCRT should be recommended, especially for Stage III VC patients. Further studies are warranted to determine who benefits from CCRT, considering primary tumor size and LN status.

The study was registered at the University Hospital Medical Information Network (protocol number: UMIN000017080) on April 8th, 2015.

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