Treatment specialty-specific characteristics and outcomes in women with vulvo-vaginal melanoma: A Japanese Gynecologic Oncology Group study (146)

Abstract

<b>Objectives:</b> To compare characteristics and outcomes of women with vulvovaginal melanoma based on treating physician types. <b>Methods:</b> This is a multi-center retrospective study via the Japanese Gynecologic Oncology Group mechanism, examining 211 women with vulvovaginal melanoma (<i>n</i>=104 for vulva and <i>n</i>=107 for vagina). In each organ group, patient/tumor characteristics and survival outcomes were compared per the treating specialty type (gynecologist vs dermatologist). Propensity score inverse probability of treatment weighting was used to assess all-cause mortality. <b>Results:</b> In the vulvar melanoma group (<i>n</i>=67 per gynecologist's vs <i>n</i>=37 per dermatologists), patients treated by dermatologists were more likely to have stage III-IV disease (54.1% vs 28.4%, odds ratio [OR]: 3.19, 95% CI: 1.21-8.43, <i>p</i>=0.019) in multivariable analysis. In a weighted model, overall survival was similar between the dermatologist and gynecologist groups (5-year rate 40.5% vs 46.0%, HR: 1.39, 95% CI: 0.84-2.29, <i>p</i>=0.203). In the vaginal melanoma group (<i>n</i>=81 per gynecologists' vs <i>n</i>=26 per dermatologists), patients treated by dermatologists were more likely to be older (median, 74 vs 64 years, <i>p</i>=0.001) and had ulcerated tumors (84.6% vs 30.9%, OR: 18.1, 95% CI: 4.87-67.2, <i>p</i><0.001) in multivariable analysis. In a weighted model, the dermatology group had improved overall survival compared to the gynecology group (5-year rate, 58.1% vs 26.8%, HR: 0.44, 95% CI: 0.26-0.75, <i>p</i>=0.003). <b>Conclusions:</b> This study suggests that women with vulvovaginal melanoma treated by dermatologists are distinct from those who are treated by gynecologists. Effects of multidisciplinary approach on treatment outcome warrant further evaluation.