Clinical Efficacy of Olaparib in IDH1/IDH2-Mutant Mesenchymal Sarcomas

PURPOSE Tumors with neomorphic mutations in IDH1/2 have defective homologous recombination repair, resulting in sensitivity to poly (ADP-ribose) polymerase (PARP) inhibition. The Olaparib Combination trial is a phase II, open-label study in which patients with solid tumors harboring IDH1/2 mutations were treated with olaparib as monotherapy, with objective response and clinical benefit rates as the primary end points. METHODS Ten patients with IDH1/2-mutant tumors by next-generation sequencing were treated with olaparib 300 mg twice daily. RESULTS Three of five patients with chondrosarcomas had clinical benefit, including one patient with a partial response and two with stable disease lasting > 7 months. A patient with pulmonary epithelioid hemangioendothelioma had stable disease lasting 11 months. In contrast, clinical benefit was not observed among four patients with cholangiocarcinoma. CONCLUSION These results indicate preliminary activity of PARP inhibition in patients with IDH1/2-mutant chondrosarcoma and pulmonary epithelioid hemangioendothelioma. Further studies of PARP inhibitors alone and in combination in this patient population are warranted.

A Case of Pulmonary Epithelioid Hemangioendothelioma with Literature Review

Pulmonary epithelioid hemangioendothelioma is a rare vascular tumor and infrequently described in medical literature as case reports and case series. Diagnosis is often incidental with high index of histopathological suspicion from clinical pathologist. The pathological pattern is quite unique with distinct immunohistochemical stains. Up to this day, there is no established standard treatment owing to the scarcity of this tumor. In this case report, we describe a case of pulmonary epithelioid hemangioendothelioma unexpectedly diagnosed with transthoracic needle biopsy, along with a review of the current literature.