Clinical value of metabolic PET parameters of primary vulvar carcinoma.

PURPOSE: We aim to establish the prognostic value of metabolic parameters of the primary tumor in patients diagnosed with vulvar squamous cell carcinoma (VSCC) who underwent a pretreatment F-18 FDG PET/CT scan. MATERIALS AND METHODS: This retrospective study included 47 patients with a histopathologically confirmed diagnosis of VSCC, and who underwent a F-18 FDG PET/CT scan prior to treatment. The disease stage and age at diagnosis, and the maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) values of the primary tumor, based on a baseline PET scan, were recorded. The relationship between these factors, and progression-free survival (PFS) and overall survival (OS) was evaluated. RESULTS: The mean age of the 47 study patients was 69.6±1.9 years. Among the patients, 18 were in early stage of the disease and 29 were in the advanced stage. The age, and SUVmax, SUVmean, MTV and TLG values were statistically significantly associated with OS and PFS. Furthermore, it was noted that OS and PFS were significantly longer in the early stage patients than in the advanced stage patients, in patients with a tumor size <4cm than those with a tumor size ≥4cm, and in patients with a negative lymph node metastasis than those with a positive lymph node metastasis. CONCLUSION: Our findings suggest that PET parameters are prognostic factors for VSCC. To the best of our knowledge, this study is the first to investigate the prognostic value of the PET parameters of primary tumors in patients with VSCC, and as such, we believe it contributes to literature.