Better drugs are needed and there are some in clinical trials that look promising. Immunotherapy is another way forward. Most of the drugs that are out there now are TKIs that work inside the cell. Immunotherapy is a way of attacking from the outside by eliciting an immune response. You get the microenvironment and the body’s immune system to help to eradicate GIST.
For the regular management of GIST, there are several prognosticators that have been established. Something that we struggle with is whether patients receive small biopsies because we are not often able to do molecular sequencing of their tumors. We cannot count the mitoses…Those are important predictors of response and how patients will do on therapy.
Unfortunately, you cannot just do large biopsies in everyone because they are often prohibited due to risk. Patients can be frail, so we need to figure out other markers of how this disease is going to behave and other surrogates for mitosis.
Singh AS, Chmielowski B, Hecht JR, et al. A randomized phase 2 study of nivolumab monotherapy versus nivolumab combined with ipilimumab in patients with metastatic or unresectable gastrointestinal stromal tumor (GIST). In: Proceedings from the 2018 Gastrointestinal Cancers Symposium; January 18-20, 2018; San Francisco, California. Abstract 55.