Pulmonary hypertension in metastatic breast cancer: a case of pulmonary tumour thrombotic microangiopathy.

Pulmonary tumour thrombotic microangiopathy (PTTM) and pulmonary tumour emboli (PTE) are distinct but related complications of malignancy. The incidence of each is exceedingly rare, unfortunately often being diagnosed postmortem. Patients with PTTM and PTE typically present with dyspnoea associated with a rapid onset of hypoxia due to pulmonary hypertension (PH), and respiratory failure that is almost certain to be fatal. The prognosis is grim due to the rapidity of the clinical decline and difficulty in establishing an ante-mortem diagnosis. We present a case of new-onset severe PH in a young woman with a recently discovered breast mass. She presented with shortness of breath and experienced rapid deterioration of her cardiopulmonary status which we attributed to PTTM. With early initiation of chemotherapy, systemic steroids and sildenafil, the patient dramatically improved. Case reports have identified early use of steroids, phosphodiesterase inhibitors and other alternative therapies as providing possible benefit in PTTM.