A nomogram for predicting recurrence‑free survival in patients with high‑risk GIST receiving adjuvant imatinib: A nationwide registry study

Despite adjuvant imatinib therapy, a substantial proportion of patients with high‑risk gastrointestinal stromal tumor (GIST) experience disease recurrence. This study aimed to identify prognostic factors associated with poor recurrence‑free survival (RFS) and develop a predictive nomogram for personalized clinical decision‑making. In the present study, a retrospective analysis was conducted of 269 patients with modified Armed Forces Institute of Pathology‑classified high‑risk GIST who underwent macroscopically complete resection and received adjuvant imatinib therapy at 11 Taiwanese centers between 2013 and 2023. All patients were intended to receive 3 years of adjuvant imatinib and were categorized into disease‑free (n=204) and recurrence (n=65) cohorts. Independent predictors of poor RFS were identified through multivariate Cox regression analysis and incorporated into a nomogram. Model performance was assessed using concordance index (C‑index) and calibration plots. The cohort comprised 149 males and 120 females with a median age of 60.9 years (range, 29‑88 years). At a median follow‑up of 62.6 months, the 1‑, 3‑ and 5‑year disease‑free survival rates were 97.0, 91.7 and 76.4%, respectively. Multivariate analysis identified male sex [hazard ratio (HR): 1.76, P=0.039], non‑gastric tumor origin with duodenum showing highest risk (HR: 6.15, P<0.0001) and shorter imatinib duration with <1 year treatment showing HR: 3.91 (P=0.002) as independent predictors of poor RFS. The resulting nomogram demonstrated robust predictive performance with good calibration and C‑index of 0.72. Nomogram‑based prognostic stratification identified three distinct groups with 5‑year survival rates of 99.2% (favorable prognosis), 68.1% (moderate prognosis) and 16.7% (poor prognosis). In the present study, a clinically applicable nomogram was developed that accurately predicts poor RFS in patients with high‑risk GIST following surgery and adjuvant imatinib therapy. While external validation is needed before clinical implementation, this prognostic tool may facilitate individualized treatment strategies and patient counseling.