Elderly patients with gastrointestinal stromal tumour (GIST) receive less treatment irrespective of performance score or comorbidity - A retrospective multicentre study in a large cohort of GIST patients.

Abstract

Objective Although gastrointestinal stromal tumours (GIST) predominantly occur in older patients, data on treatment patterns in elderly GIST patients are scarce.Methods Patients registered in the Dutch GIST Registry (DGR) from January 2009 until December 2016 were included. Differences in treatment patterns between elderly (≥75 years) and younger patients were compared. Multivariate analyses were conducted using logistic regression.Results Data of 145 elderly and 665 non-elderly patients were registered (median age 78 and 60 years respectively). In elderly patients, performance score (WHO-PS) and age-adjusted Charlson comorbidity index (ACCI) were significantly higher (p < 0.05; p < 0.001), and albumin level significantly lower (p = 0.04). Hundred-and-nine (75.2%) elderly and 503 (75.6%) non-elderly patients had only localised disease. Surgery was performed in 57% of elderly versus 84% of non-elderly patients (p = 0.003, OR: 0.26, 95% CI: 0.11-0.63). No differences in surgery outcome or complications were found. Thirty-eight percent of elderly with an indication for adjuvant treatment did receive imatinib versus 68% of non-elderly (p = 0.04, OR: 0.47, 95% CI: 0.23-0.95). Thirty-six elderly and 162 non-elderly patients had metastatic disease. Palliative imatinib was equally given (mean dose 400 mg) and adverse events were mostly minor (p = 0.71). In elderly, drug-related toxicity was in 32.7% reason to discontinue imatinib versus 5.1% in non-elderly (p = 0.001, OR 13.5, 95% CI: 2.8-65.0). Median progression-free survival (PFS) was 24 months in elderly and 33 months in non-elderly (p = 0.10). Median overall survival (OS) was 34 months and 59 months respectively (p = 0.01).Conclusions Elderly GIST patients with localised disease receive less surgery and adjuvant treatment, irrespective of comorbidity and performance score. Drug-related toxicity results more often in treatment discontinuation. This possibly results in poor outcome.