Pulmonary metastatic paraganglioma with angiosarcomatous differentiation: a rare case report and literature review.

Paragangliomas are rare neuroendocrine tumors that can rarely undergo malignant transformation. Angiosarcomatous differentiation is an exceptionally uncommon event with limited reports. This case describes a patient with a previously irradiated vagal paraganglioma that transformed into a metastatic pulmonary paraganglioma with angiosarcomatous features, highlighting the importance of long-term surveillance in irradiated paragangliomas. The patient presented with shortness of breath due to persistent pleural effusion. Despite receiving thoracentesis and palliative radiation therapy, the patient ultimately expired from hypoxic respiratory failure after two months. We add to the limited literature on sarcomatous transformation in paragangliomas and emphasize the importance of considering secondary malignancies in paragangliomas with unusual transformation, and potentially worse prognosis.