Clinical outcomes of medical treatments for progressive desmoid tumors following active surveillance: a systematic review.

Approximately 80% of desmoid tumors (DTs) show spontaneous regression or disease stabilization during first-line active surveillance. Medical treatment can be considered in cases of disease progression. This systematic review aimed to evaluate the effectiveness and toxicity of each medical treatment by reviewing only the studies that included progressive disease as the inclusion criterion. We searched the EMBASE, PubMed, and CENTRAL databases to identify published studies for progressive DTs. The disease control rates of the medical treatments, such as low-dose chemotherapy with methotrexate plus vinblastine or vinorelbine, imatinib, sorafenib, pazopanib, nilotinib, anlotinib, doxorubicin-based agents, liposomal doxorubicin, hydroxyurea, and oral vinorelbine for progressive DTs were 71-100%, 78-92%, 67-96%, 84%, 88%, 86%, 89-100%, 90-100%, 75%, and 64%, respectively. Low-dose chemotherapy, sorafenib, pazopanib, nilotinib, anlotinib, and liposomal doxorubicin had similar toxicities. Sorafenib and pazopanib were less toxic than imatinib. Doxorubicin-based chemotherapy was associated with the highest toxicity. Hydroxyurea and oral vinorelbine exhibited the lowest toxicity. Stepwise therapy escalation from an initial, less toxic treatment to more toxic agents is recommended for progressive DTs. Sorafenib and pazopanib had limited on-treatment side effects but had the possibility to induce long-term treatment-related side effects. In contrast, low-dose chemotherapy has some on-treatment side effects and is known to have very low long-term toxicity. Thus, for progressive DTs following active surveillance, low-dose chemotherapy is recommended in young patients as long-term side effects are minor, whereas therapies such as sorafenib and pazopanib is recommended for older patients as early side effects are minor.