Impact of a risk-based follow-up in patients affected by gastrointestinal stromal tumour

Abstract

Background: Follow-up aims to precociously identify recurrences, metastases or treatment-related adverse events so as to undertake the appropriate therapy. Guidelines admit lack of knowledge on optimal surveillance schedule, but suggest follow-up based on experts' opinion and risk stratification. To identify the impact, if any, of regular follow-up, we interrogated our prospectively collected database whether early detection of recurrences affected both clinical management and, likely, the outcome.

Patients and methods: We required information to be available on primary surgery and ≥3°years of follow-up for non-recurring patients. We analysed recurrence characteristics (asymptomatic versus symptomatic, low- versus high tumour burden) and computed tomography (CT) scan counts to detect one recurrence. Kaplan-Meier method estimated recurrence-free survival (RFS), post-recurrence progression-free survival (PR-PFS), and disease-specific overall survival (OS). Comparisons used Hazard ratios (HR) with 95% confidence intervals (CIs). Multivariate analyses employed the Cox proportional hazards model. All tests were two-sided.

Results: Between 01/2001 and 12/2012 we found 233 study-eligible patients. Estimated 5- and 10-year RFS were 61.8% and 50.4%, respectively. After a 68-month median follow-up, we observed 94 (40.3%) recurrences [73/94 (77.7%) asymptomatic versus 21/94 (22.3%) symptomatic and 45/94 (47.9%) low- versus 49/94 (52.1%) high tumour burden]. Multivariate analysis revealed that symptomatic and high tumour burden recurrences were highly predictive of both worse PR-PFS (HR:3.19, P < 0.001; HR:2.80, P = 0.003, respectively) and OS (HR:3.65, P < 0.001; HR:2.38, P = 0.026, respectively). Finally, 29 second (primary) cancers were detected during follow-up.

Conclusions: Regular follow-up detects recurrences at an earlier stage and may be associated with a better PR-PFS and OS for these patients. In the absence of randomised trials, these evidences support follow-up effort and cost.

Keywords: Computerised tomography; Follow-up; GIST; Gastrointestinal stromal tumour; Radiation exposure; Risk stratification; Surgery; Treatment guidelines.