Case Report: Recurrent uterine inflammatory myofibroblastic tumor harboring IGFBP5-ALK fusion with sustained response to iruplinalkib.

Inflammatory myofibroblastic tumor (IMT) is an extremely rare mesenchymal tumor with approximately 50% of cases harbor anaplastic lymphoma kinase (ALK) gene rearrangements. The tyrosine kinase inhibitor (TKI) treatment has been increasingly common for IMTs with ALK fusions, but evidence for the efficacy of TKIs in uterine IMT is lacking. In this report, we present a case of patient with recurrent uterine IMT harboring IGFBP5-ALK fusion. The patient was initially misdiagnosed as uterine myxoid leiomyoma and then leiomyosarcoma after recurring. Then the patient was recommended ALK-TKIs treatment after detecting ALK rearrangement, and achieved complete response (CR) from a second-generation ALK-TKI inhibitor, iruplinalkib, after resistance to the first-generation inhibitor crizotinib. This is the first case of iruplinalkib achieved therapeutic success in uterine IMT, suggesting that a sequential ALK-TKIs with iruplinalkib could be an optimal targeted therapeutic strategy for ALK-rearranged IMTs.