Study in Low Risk Gastrointestinal Stromal Tumor (GISTs)

In the field of soft tissue sarcomas, Gastrointestinal Stromal Tumors (GIST) represents a really peculiar neoplasm for its biological and clinical properties. Surgery (if feasible) is the main therapeutic approach for all the patients with localized disease, while a pharmacological adjuvant treatment is reserved to those with a relevant risk of recurrence/progression.

After tumor removal, clinical and radiological follow-up is of central importance to early intercept recurrence and to evaluate the most correct subsequent therapeutic approach. In particular, for the group of patients with GIST at very-low and low risk of recurrence/progression, the evidences to support a specific follow-up program and its features are poor.

On the basis of the aforementioned considerations, we propose a multi-institutional retrospective study in order to identify the most relevant and advisable features of follow-up, and to explore its impact on principal clinical outcomes. Moreover, a dedicated effort will be pursued to identify the peculiar characteristics (if any) of patients that experienced recurrence of the disease.

The study will collect data about patients affected by primary GIST at very-low and low risk of recurrence/progression, referred to participating Institutions between January 2000 and February 2020

Inclusion criteria

• >18 years at diagnosis
• primary GIST removed by surgery or endoscopic procedures
• availability of medical data needed for the study
• very-low and low risk GIST defined as:

• largest size of < 3 cm (for all sites of origin)
• gastric GIST with ≤ 5/50 High Power Fields (HPF) mitoses and ≤ 10 cm in the largest size
• gastric GIST with > 5/50 HPF mitoses and ≤ 5 cm in the largest size
• intestinal GIST with ≤ 5/50 HPF mitoses and ≤ 5 cm in the largest size

Exclusion criteria

• Metastases at diagnosis.
• Previous treatment with imatinib