Vulvovaginal myofibroblastoma: expanding the morphological and immunohistochemical spectrum. A clinicopathologic study of 10 cases

Hum Pathol. 2012 Feb;43(2):243-53. doi: 10.1016/j.humpath.2011.04.027. Epub 2011 Aug 4.

Abstract

We analyzed the clinicopathologic features of 10 cases of vulvovaginal myofibroblastoma to widen its morphological and immunohistochemical spectrum. Most tumors (8/10 cases) were located in the vagina. The patients' age ranged from 44 to 77 years, and tumor size ranged from 0.4 to 3 cm. Histologically, 5 tumors had the characteristics of vulvovaginal myofibroblastoma. In addition, we identified 3 cases composed of spindle-shaped cells arranged in short fascicles with intervening thick collagen bands, closely reminiscent of mammary myofibroblastoma. Notably, 1 case resembled Sertoli cell tumor, sclerosing type, because of its predominant cord-like arrangement. In another case, there were highly cellular areas composed of uniform-packed, rounded cells that, at low magnification, looked like a malignant "small round blue cell tumor." A variably thick band of native connective tissue separated tumors from the overlying squamous epithelium even if, in 3 cases, tumor cells extended up to the epithelium. In 7 cases, a variable number of vessels showed perivascular hyalinization. Only rare mitotic figures were identified. All tumors were diffusely positive for vimentin, desmin, and CD99. A variable staining intensity was observed for CD34, Bcl-2, B-cell lymphoma 2 (Bcl-2) CD10, estrogen receptor, and progesterone receptor in most cases, but none expressed α-smooth muscle actin. We emphasize that vulvovaginal myofibroblastoma encompasses a morphological spectrum wider than previously described. The overlapping morphological and immunohistochemical features of vulvovaginal and mammary myofibroblastomas led us to speculate that these are related entities with morphological variations on a common basic theme likely dependent on anatomical location.

Publication types

  • Case Reports

MeSH terms

  • 12E7 Antigen
  • Adult
  • Aged
  • Antigens, CD / metabolism
  • Biomarkers, Tumor / metabolism
  • Cell Adhesion Molecules / metabolism
  • Desmin / metabolism
  • Female
  • Humans
  • Middle Aged
  • Neoplasms, Muscle Tissue / metabolism
  • Neoplasms, Muscle Tissue / pathology*
  • Neoplasms, Muscle Tissue / surgery
  • Treatment Outcome
  • Vaginal Neoplasms / metabolism
  • Vaginal Neoplasms / pathology*
  • Vaginal Neoplasms / surgery
  • Vimentin / metabolism
  • Vulvar Neoplasms / metabolism
  • Vulvar Neoplasms / pathology*
  • Vulvar Neoplasms / surgery

Substances

  • 12E7 Antigen
  • Antigens, CD
  • Biomarkers, Tumor
  • CD99 protein, human
  • Cell Adhesion Molecules
  • Desmin
  • Vimentin