Pulmonary Epithelioid Trophoblastic Tumor Without Demonstrable Uterine Involvement: A Case Report and Literature Review Highlighting Diagnostic Challenges and Multidisciplinary Management.

Background

Pulmonary epithelioid trophoblastic tumor (ETT) without demonstrable uterine involvement is an exceedingly rare form of gestational trophoblastic neoplasia. Its non-specific presentation often results in misdiagnosis, commonly as ectopic pregnancy. Case Presentation: A 39-year-old woman, para 2, presented with abnormal uterine bleeding and an elevated serum β-human chorionic gonadotropin (β-hCG) level of 978 mIU/mL. Despite the absence of sonographic evidence for either intrauterine or ectopic pregnancy, she was initially misdiagnosed with ectopic gestation. Following a failed systemic methotrexate therapy, she underwent a non-diagnostic laparoscopic bilateral salpingectomy and curettage; however, her β-hCG levels continued to rise persistently. A computed tomography (CT) scan performed one month later revealed a solitary mass measuring 57 × 40 mm in the right lower lobe of the lung. A multidisciplinary team subsequently decided on a right lower lobectomy. Postoperatively, the patient's β-hCG levels normalized rapidly. Histopathological examination of the lung mass confirmed the diagnosis of pulmonary ETT without demonstrable uterine involvement. She received 3 cycles of combination EMA/Co chemotherapy (etoposide, methotrexate, and actinomycin D, followed by cyclophosphamide and vincristine), and the serum β-hCG level dropped to normal. At the 3-year posttreatment follow-up, the patient reported regular menstrual cycles, with serum β-hCG levels consistently within normal limits.

Conclusions

This case highlights that persistent elevation of β-hCG in the absence of pelvic pathology should prompt a comprehensive investigation for an extrauterine source. Pulmonary ETT must be included in the differential diagnosis for reproductive-aged women presenting with a pulmonary mass and elevated β-hCG levels. A multidisciplinary approach enabled both definitive diagnosis and fertility-sparing management in this patient; broader conclusions about treatment efficacy await larger series.