A Case Report on Primary Pulmonary Choriocarcinoma

Primary choriocarcinoma originating in the lung is a rare entity. These are highly malignant intrapulmonary tumors with a notoriously poor prognosis. The pathogenesis is unclear. A 34-year-old lady, with a history of abortion six months back, presented with left-sided chest pain for one month, dyspnea on exertion, weight loss, and loss of appetite. Computed tomography (CT) of the thorax was suggestive of a mass lesion 4 x 5 cm at the left upper lobe, which was invading the chest wall, and pleural effusion, histopathologically defined as adenocarcinoma. A positron emission tomography-computed tomography (PET-CT) scan showed a fluorodeoxyglucose (FDG) avid lesion in the left upper lobe of size 4 x 5 with invasion to the chest wall with no evidence of distant metastases. Urine pregnancy test (UPT) was negative for this patient. Thus, the patient was initially diagnosed with stage cT3N0M0 adenocarcinoma of left lung cancer. The sample was sent for the lung next-generation sequencing (NGS) panel. Meanwhile, the patient was empirically started on gefitinib. Tumor markers revealed raised beta-human chorionic gonadotropin (β-hCG) to 1,79,000 IU/ml. A review biopsy was done, which was suggestive of choriocarcinoma. Genetic testing of lung biopsy suggestive of XX chromosome, confirming the diagnosis of primary pulmonary choriocarcinoma (PPC). The patient was planned for chemotherapy with etoposide and cisplatin. The patient underwent embolization of the left internal mammary artery (IMA) and branches of the left subclavian vein. There was a gradual fall in β-hCG after the second dose of chemotherapy on day 7. For the diagnosis of PPC, immunohistochemistry (IHC) staining, β-hCG measurement, and examination to exclude primary gonadal malignancies are essential. A combination of surgery and chemotherapy is a favorable treatment. As it's a highly vascular tumor, selective arterial embolization can be life-saving in case of bleeding.