Epithelioid trophoblastic tumor: report of two cases in postmenopausal women with literature review and emphasis on cytological findings

Acta Cytol. 2014;58(2):198-210. doi: 10.1159/000357966. Epub 2014 Feb 7.

Abstract

Background: Epithelioid trophoblastic tumor (ETT) is a rare gestational trophoblastic neoplasm of intermediate trophoblasts. It was first described by Shih and Kurman [Am J Surg Pathol 1998;22:1393-1403] who outlined its clinicopathologic characteristics in 14 cases, establishing it as a distinct entity of gestational trophoblastic tumors. It represents 1.39% of all gestational trophoblastic diseases. Most cases are reported in reproductive-age women following a prior gestation with a time interval between 2 weeks and 30 years. ETT is extremely rare in postmenopausal women. It is commonly misdiagnosed as a squamous cell carcinoma (SCC), poorly differentiated carcinoma or another gestational trophoblastic tumor. Limited data is available regarding its cytological features on Pap smears.

Cases: We report 2 cases of uterine ETT occurring in postmenopausal women. In both cases, an initial diagnosis of an SCC and a poorly differentiated carcinoma was rendered. We highlight the features of ETT helpful in differentiating it from other mimickers with emphasis on rarely reported cytological features of this neoplasm.

Conclusion: ETT is a rare tumor with characteristic cytological features, but is commonly confused with SCC. A high index of suspicion is needed to make the correct diagnosis or to raise the consideration of ETT, especially in cases with an increased β-human chorionic gonadotropin.

Publication types

  • Case Reports

MeSH terms

  • Carcinoma, Squamous Cell / diagnosis
  • Carcinoma, Squamous Cell / pathology
  • Diagnostic Errors
  • Epithelioid Cells / pathology*
  • Female
  • Humans
  • Middle Aged
  • Postmenopause
  • Trophoblastic Neoplasms / diagnosis*
  • Trophoblastic Neoplasms / pathology*