Vulvar malignancies: an interdisciplinary perspective

Abstract

Vulvar cancer represents the fourth most common gynecologic malignancy and is often encountered by the general Dermatologist or Gynecologist. Dermatooncologists and Gynecologic Oncologists share expertise in this field and the diagnosis and treatment should ideally be interdisciplinary. All subtypes are typically seen in the later decades of life, although all histologic subtypes have been described in women younger than 30 years. The diagnosis is often delayed. Exact mapping of biopsies is of high importance, as the location and distance from the midline guides the surgical approach depending on the underlying histology. Squamous cell carcinoma accounts for more than 76 % of vulvar cancer with vulvar intraepithelial neoplasia being an important precursor. Basal cell carcinoma is the second most common vulvar malignancy. Melanoma accounts for 5.7 % of vulvar cancer and has a worse prognosis compared to cutaneous melanoma. Most of the trials on checkpoint inhibitors and targeted therapy have not excluded patients with vulvar melanoma and the preliminary evidence is reviewed in the manuscript. Surgery remains the primary treatment modality of locally resectable vulvar cancer. In view of the rarity, the procedure should be performed in dedicated cancer centers to achieve optimal disease control and maintain continence and sexual function whenever possible.

Figure 1

Relative frequency of histologic subtypes of vulvar malignancies. Percentage of histologic subtypes of vulvar malignancies from the National Cancer Institute, Surveillance, Epidemiology and End Results, SEER‐18 population, Nov 2018 submission 4. Abbr.: Adeno‐Ca, Adenocarcinoma; BCC, basal cell carcinoma; SCC, squamous cell carcinoma.

Figure 2

Vulvar anatomy and mapping of lesions. Vulvar anatomy (a). Vulva‐mapping, biopsy sites should be reported using the exact position on the clock‐face with distance from midline and vaginal introitus as well as describing the anatomic location (b).

Figure 3

Pathophysiology of usual‐type and differentiated VIN and its progression to SCC. Suggested progression of usual‐type (uVIN) and differentiated vulvar intraepithelial neoplasia (dVIN) to squamous cell carcinoma (SCC). uVIN: HPV‐protein E6 degrades the tumor suppressor p53; HPV‐protein E7 inactivates the tumor suppressor RB and releases E2F resulting in hyperproliferation. On IHC p16 is typically positive and p53 negative. dVIN: chronic dermatoses, especially Lichen sclerosus and Lichen planus, can progress to dVIN and SCC. On IHC p16 is typically negative and p53 positive. Abbr.: HPV, human papilloma virus; IHC, immunohistochemistry; SCC, squamous cell carcinoma; VIN, vulvar intraepithelial neoplasia. *Rate of progression according to van de Nieuwenhof et al. 11.

Figure 4

Macroscopic, dermoscopic and histopathologic features of vulvar malignancies. Vulvar squamous cell carcinoma (reproduced with permission of John Wiley & Sons from Vaccari et al. 113 and under the CC license from Alkatout et al. 114) (a–c). Vulvar melanoma (reproduced under the CC license from Rogers et al. 115) (d–f). Extramammary Paget's disease (i reproduced under the CC license from van der Linden et al. 116) (g–i). Basal cell carcinoma (reproduced under the CC license from Cinotti et al. 97) (j–l).