Tenosynovial giant cell tumour (TGCT) is a rare, locally aggressive neoplasm, overexpresses colony-stimulating factor 1 (CSF1). Surgery is standard with no approved systemic therapy.
According to a commentary, understanding, monitoring, and managing the side-effects of all treatments will be important to optimise systemic therapy for patients with TGCT as these patients might be less willing to cope with adverse event-related and study-related procedures. It notes that so far, most of these agents have been tested in selected patients who had an inoperable, progressive, or recurrent disease, who represent a small group of severely affected patients that are a part of a much larger, often less complicated group of patients. It adds that given the response seen with pexidartinib and emactuzumab in advanced TGCT, it is tempting to use these treatments in earlier stages of the disease, which will require even more caution regarding patient selection, duration of therapy, management of adverse events, and timing of surgery. It suggests that the patients who would benefit most from systemic therapy should be identified on the basis of molecular tumour features sensitive to that specific treatment.