A Case of Vaginal Malignant Melanoma Completely Resected by Radical Surgery

Abstract

BACKGROUND Primary vaginal malignant melanoma is a rare and aggressive tumor with a high risk of local recurrence and distant metastasis. Although there are several available treatment options, none are considered as standard. Surgical resection is the first treatment choice because of its superior survival benefits. CASE REPORT The patient was a 56-year-old woman with a vaginal mass. At the first visit to our institution, a 20×20 mm black and flat lesion on the lower third of the posterior vaginal wall and a polypoid mass near the vaginal fornix were detected by gynecologic examination. Study of the tumor on the posterior vaginal wall suggested that it did not extend to the uterine cervix. The preoperative diagnosis was vaginal malignant melanoma FIGO stage I (cT1, cN0, cM0). The patient underwent a total vaginectomy, pelvic and inguinal lymphadenectomy, modified radical hysterectomy, and bilateral salpingo-oophorectomy. The tumor cells were arranged in sheets and nests and exhibited nuclear pleomorphism, eosinophilic cytoplasm, brisk mitotic activity, and melanin production. The overlying mucosa was ulcerated. The tumor thickness was 2.5 mm and no residual lesion was found at the surgical margin. No adjuvant therapies were performed. The patient is alive without recurrence 15 months after the initial treatment. CONCLUSIONS This is a case of vaginal malignant melanoma for which complete response was achieved by radical tumor resection, without severe adverse effects and with no observed recurrence 15 months after the surgery.

Figure 1.

Preoperative examinations: (A) Internal examination showed a 20×20 mm black and flat lesion on the posterior vaginal wall. (B) T2-weighted magnetic resonance imaging revealed no vaginal or uterus cervix mass. (C) Pap ×100. Vaginal cytology showed atypical cells with nuclear pleomorphisms and melanin production. (D) Immunohistochemical staining of vaginal cytology cell blocks showed the tumor cells were positive for melan-A.

Figure 2.

Postoperative examinations: (A) Macroscopically, a tumor of size 45×25 mm with a black surface was detected in the posterior vaginal wall (yellow arrows). (B) Hematoxylin and eosin ×4; and (C) Hematoxylin and eosin ×40. Microscopically, the tumor cells were arranged in sheets and nests and exhibited nuclear pleomorphism, an eosinophilic cytoplasm, brisk mitotic activity, and melanin production. Immunohistochemically, the tumor was positive for (D) SOX10 and (E) the Ki-67 labeling index was 70%.