Synchronous occurrence of gastrointestinal stromal tumors and other digestive tract malignancies in the elderly

BACKGROUND/AIMS: Elderly patients with gastrointestinal stromal tumors (GISTs) synchronous with other digestive tract malignancies have been rarely reported. In this study, clinicopathological characteristics were evaluated among elderly patients with GISTs with or without coexisting digestive tract malignancies. METHODS: A total of 161 patients (≥65 years) were retrospectively reviewed at the West China Hospital, Sichuan University from January 2009 to June 2014. RESULTS: Sixty-one patients were diagnosed with synchronous digestive tract malignancies (synchronous group), whereas 100 patients were diagnosed with no synchronous condition (no-synchronous group). The synchronous group exhibited a higher percentage of males (70.49% vs. 53.00%, P = 0.028) and poorer Eastern Cooperative Oncology Group performance status than the no-synchronous group (P = 0.029). The three-year overall survival (OS) rate was significantly lower among patients with synchronous digestive tract malignancies than that among patients without synchronous condition (64.5% vs. 84.0%, P = 0.003). Multivariate analysis showed that the presence of synchronous digestive tract malignancies (P = 0.002), co-morbidity (P = 0.004), and mitotic count ≥10 mitoses/50 high power fields (P = 0.012) were associated with poor OS. CONCLUSIONS: A synchronous condition with other digestive tract malignancies is common in elderly patients with GISTs. OS primarily depends on synchronous digestive tract malignancies, mitotic count, and co-morbidity.