Numerical, dimensional or mixed progression disease to imatinib as prognostic factor in patients with metastatic GIST.

11040 Background: The majority of GIST patients with advanced disease initially achieves disease control from imatinib treatment. Approximately 10% of patients progresses within 6 months of starting therapy (primary resistance) and also 50-60% of the responding patients develops progression disease within two years (secondary resistance). Progression disease (PD) can be numerical, dimensional or mixed. The known prognostic factors of risk stratification in local disease are tumor size, mitotic activity and anatomic site. In this retrospective analysis we explore several clinical factors affecting survival in metastatic setting. Methods: The population included in this large database of 128…

Predictive factors of response to Sunitinib in metastatic Gastrointestinal Stromal Tumors (mGISTs): A retrospective analysis

Personalization of regorafenib treatment in metastatic gastrointestinal stromal tumours in real-life clinical practice

Background: Regorafenib (REG) has now been approved as the standard third-line therapy in metastatic gastrointestinal stromal tumour (GIST) patients at the recommended dose and schedule of 160 mg once daily for the first 3 weeks of each 4-week cycle. However, it has a relevant toxicity profile that mainly occurs within the first cycles of therapy, and dose and schedule adjustments are often required to reduce the frequency or severity of adverse events and to avoid early treatment discontinuation. To date, large amounts of data on the use of REG in metastatic GIST patients in daily clinical practice are not available, and we lack information about how this treatment personalization really a…

Predictive Factors of Response to Sunitinib in Imatinib-Resistant Gastrointestinal Stromal Tumors (GISTs): A Multi-Institutional Study

Imatinib 400 mg is the standard of care for medical treatment of advanced GISTs. In the majority of cases, however, GISTs eventually develop resistance to imatinib. The optimal second line treatment has not been established yet and imatinib dose escalation (800 mg) or sunitinib represent two feasible options. The objective of this retrospective, multi-institutional, study is to analyze the validity of several parameters as possible predictive factors of response to sunitinib after imatinib failure. We reviewed 128 metastatic GISTs treated with sunitinib between January 2007 to June 2017. Primary tumour site, metastatic site, c-KIT/PDGFR-α mutational status, PET-FDG status and type…