Contributed by Dinesh Pradhan, MD and Gloria Carter, MD
A multigravida African-American female in her 30s presented with a 4 month history of bleeding during intercourse. She also complained of external irritation secondary to an enlarging left labial mass. She had recently removed an intra-uterine device due to malposition secondary to the presence of submucosal fibroid detected on ultrasonography (US). She also had a slowly enlarging cervical polyp.
Pelvic examination revealed a 3-cm fluctuant, soft mobile raised lesion on the left labia between the labia majora and labia minora. The surrounding vulvar tissue appeared to be normal. Patient's past surgical history was significant for bilateral breast reduction 5 years back, when fibroadenomas with florid ductal epithelial hyperplasia were noted in both breasts.
The vulvar lesion was first biopsied and then completely excised along with polypectomy of the cervical polyp.
Transvaginal pelvic ultrasonography performed the previous year was significant for leiomyomatous uterus.
Gross examination of the excised lesion revealed a well circumscribed tan white polypoid mass measuring 2.5 x 2.3 x 2 cm just beneath an ellipse of wrinkled disrupted skin. The cut surfaces were gray-white bulging with numerous slits. There was grossly no hemorrhage or necrosis.
Hematoxylin and eosin sections revealed a well circumscribed biphasic lesion beneath the unremarkable skin. The benign fibroblastic stroma was surrounded by compressed ducts which were mostly displaying intracanalicular pattern. The glands were lined by luminal columnar cells and abluminal myoepithelial cells. (H&E - Fig. 01, Fig. 02 and Fig. 03)
Immunohistochemical stains revealed that the ductal epithelial cells were positive for GATA3 and negative for PAX-8. The myoepithelial cells showed nuclear positivity for P63 and cytoplasmic immunoreactivity for smooth muscle myosin heavy chain. Ki-67 labelling index was very low.(Fig. 04-GATA3, Fig. 05-Pax8, Fig. 6-P63, Fig. 07-SMMHC)