Imatinib dramatically alleviates pulmonary tumour thrombotic microangiopathy induced by gastric cancer

Pulmonary tumour thrombotic microangiopathy (PTTM) is a rare complication of cancer, which can be lethal due to progressive pulmonary hypertension (PH). Several case reports have demonstrated that imatinib, a platelet-derived growth factor receptor-tyrosine kinase inhibitor, can improve severe PH in patients with PTTM. We describe the case of a 56-year-old woman. Her mean pulmonary arterial pressure (mPAP) was 47 mm Hg, and her dyspnoea worsened rapidly over several days. Although pulmonary embolism was not observed on CT, enlargement of the para-aortic lymph nodes was detected. Gastro-oesophageal endoscopy revealed signet-ring cell carcinoma. We diagnosed her as having PTTM based on her clinical course, and started treatment with imatinib. Five days after its administration, her mPAP decreased dramatically. She was discharged and lived without symptoms of PH until her death due to systemic metastasis of carcinoma. In some cases of PTTM, imatinib may be an effective therapeutic option for PH.