Unexpected pulmonary hypertensive crisis after surgery for ocular malignant melanoma

Aims To report a case of unexpected pulmonary hypertensive crisis caused by endothelin release from melanoma cells after surgery for choroidal melanoma. Main methods A 56-year-old man suddenly developed dyspnea after resection of choroidal melanoma. Worsening hypoxia required intensive treatment, including percutaneous cardiopulmonary support, after which a series of tests were immediately performed. The tentative diagnosis was idiopathic pulmonary arterial hypertension. Key findings Previous studies noted a significant association between melanoma and endothelin (ET)-1. We hypothesized that a substantial amount of ET-1 had been released from malignant melanoma cells during resection, thus triggering the pulmonary hypertensive crisis in our patient. The patient fully recovered after intensive treatment and administration of the endothelin receptor antagonist bosentan. Significance The success of bosentan treatment, along with the extremely high level of ET-1 on pathologic analysis, confirmed our hypothesis regarding the increase in plasma ET-1 level.