Pulmonary hypertension due to isolated metastatic squamous cell carcinoma thromboemboli

Pulmonary hypertension as the initial presentation of occult malignancy is extremely rare. The differential diagnosis of pulmonary hypertension due to arterial tumour embolism is often overlooked and deserves contemplation. Our case report details the presentation of cardiorespiratory decompensation from an assumed classic saddle pulmonary embolus in a previously fit, well 80-year-old gentleman. The patient underwent successful pulmonary thromboendarterectomy, however, intraoperatively the specimen was noted to be atypical. This resulted in the surprising definitive diagnosis of thromboembolic pulmonary hypertension secondary to laminated thrombi of metastatic squamous cell tumour emboli. The site of tumour origin was however not histologically apparent and was unable to be elucidated on extensive further investigation. Post-operatively the patient had considerable subjective and functional improvement returning to activities of daily living. He however passed away some 9 months later.