03 February 2020
Inflammatory myofibroblastic tumor: The experience of the European paediatric Soft Tissue Sarcoma Study Group (EpSSG)
The European Journal of Cancer recently published the EpSSG experience on inflammatory myofibroblastic tumor (IMT), a rare neoplasm of intermediate malignancy mainly affecting young people. The study reported on 60 patients (59 with localized, 1 with multifocal disease; 40 ALK-positive) and demonstrated the generally good prognosis for this tumor, even in patients with initially unresectable disease and ALK- negative cases. The 5 -year event-free survival (EFS) and overall survival (OS) were 82.9% and 98.1%, respectively.
The study discussed on the role of systemic therapy in patients with unresectable disease, since the panorama of treatments for IMT is rapidly changing due to the availability of ALK (but also ROS1 and NTRK) inhibitors. In the EpSSG series, the overall response to systemic therapy was 64%: 8/10 cases responded to vinblastine-methotrexate chemotherapy, and 5/5 to ALK-inhibitors. This means that chemotherapy is still a valid option (especially with minimal-morbidity options like vinblastine and low- dose methotrexate). On the other hand, the efficacy of targeted inhibitor-based therapies seems to point to their use as the standard of care; nevertheless, many questions remain unanswered concerning the availability and cost of ALK inhibitors, the duration of such treatments, their long-term effects, the onset (and mechanism) of resistance, the role of second-generation ALK inhibitors (and ROS1 and NTRK inhibitors), the treatment of ALK-negative patients, and so on. Larger studies involving both pediatric and adult patients are needed to clarify all these aspects.
The study discussed on the role of systemic therapy in patients with unresectable disease, since the panorama of treatments for IMT is rapidly changing due to the availability of ALK (but also ROS1 and NTRK) inhibitors. In the EpSSG series, the overall response to systemic therapy was 64%: 8/10 cases responded to vinblastine-methotrexate chemotherapy, and 5/5 to ALK-inhibitors. This means that chemotherapy is still a valid option (especially with minimal-morbidity options like vinblastine and low- dose methotrexate). On the other hand, the efficacy of targeted inhibitor-based therapies seems to point to their use as the standard of care; nevertheless, many questions remain unanswered concerning the availability and cost of ALK inhibitors, the duration of such treatments, their long-term effects, the onset (and mechanism) of resistance, the role of second-generation ALK inhibitors (and ROS1 and NTRK inhibitors), the treatment of ALK-negative patients, and so on. Larger studies involving both pediatric and adult patients are needed to clarify all these aspects.
