Cure can only be expected in small, completely resected GIST (Herold 2022). Nevertheless, recurrence or metastasis occurs in approximately 50% of patients after complete resection (Rammohan 2013).
Predictors at progression are:
- tumor size
- mitotic rate
- Tumor location:
GIST localized in the stomach, for example, have a better prognosis than small bowel GIST (van der Zwan 2005).
In advanced GIST, the median survival time is strongly dependent on:
- the molecular mutation analysis
- The response to drug therapy (Herold 2022).
The 5-year recurrence-free survival rate after surgery is approximately 59.9% (Akahoshi 2018).
Median survival of patients with advanced GIST have a 9-year survival rate of 35-49% with imatinib therapy (Rammohan 2013).
Follow-up
The goal of follow-up is early detection of local recurrence, peritoneal dissemination, and any liver metastases. A contrast CT should therefore be performed from the diaphragm to the inguinal region (Akahoshi 2018). A follow-up period of more than 10 years is recommended (Akahoshi 2018).
During the first 3 - 5 years, most recurrences occur. From there, intensive follow-up is required during this period (Rammohan 2013).
According to the Japanese clinical practice guideline for GIST by Nishida (2008), the recommended intervals for follow-up are as follows:
- GIST with very low and moderate risk should be followed up by CT every 6 - 12 months
- GIST with high risk or with metastases, peritoneal dissemination, infiltration of other organs, or injury to the pseudocapsule by CT every 4 - 6 months (Akahoshi 2018).
Werner (2020) recommends CT as the standard imaging modality:
- in patients with very low risk and R0 resection
- regular follow-up is not required
- for patients in the low-risk group with R0 resection
- every 6 months for a total of 5 years
- in patients of the medium- and high-risk group:
- until year 5 of disease follow-up every 3 months
- year 6 - 8: every 6 months
- year 9 - 13: 1 x yearly