Group 4 pulmonary hypertension due to choriocarcinoma after molar pregnancy: case report and review.

A 46-year-old Mexican woman developed type 4 pulmonary hypertension (PH) due to tumor embolism from choriocarcinoma (CC), which is an uncommon presentation of this malignancy. She presented with precordial pain, dyspnea, and rapid functional decline. Imaging revealed obstructive thrombi in the pulmonary arteries, initially suggestive of operable chronic thromboembolic PH (CTEPH). A bilateral subsegmental pulmonary thromboendarterectomy was performed, the standard treatment for CTEPH, aimed at removing obstructive material and restoring hemodynamic stability. However, histopathological examination of the surgical specimens showed malignant cells positive for human chorionic gonadotropin, confirming CC as the source of tumor emboli and leading to reclassification of her condition as type 4.2.2 PH. The patient died intraoperatively due to severe airway bleeding and inability to wean from cardiopulmonary bypass.