Impact of diabetes mellitus on treatment outcomes in patients with nasopharyngeal cancer

Abstract

Background and purpose: To determine the influence of diabetes mellitus on stages and long-term outcomes among patients with nasopharyngeal cancer.

Material and methods: The study summarized 37 patients who were diagnosed as having diabetes mellitus and nasopharyngeal cancer and treated by radiotherapy between January 1999 and December 1999. With a median follow-up of 34.6 mo, we analyzed differences in RFS, MFS, DFS, and OS between the diabetes and the non-diabetes group.

Results: 37 patients were involved in our study. According to the Chinese Fuzhou staging system for NPC, which was modified in 1992, 2 patients belong to stage I, 9 stage II, 17 stage III, and 6 stage IV. The 4-yr RFS of diabetes group and non-diabetes group was 52.1% vs 68.2%, the 4-yr MFS was 73.0% vs 72.0%, the 4-yr DFS was 35.1% vs 65.1%, and the OS was 67.6% vs 75.7%. The Wilcoxon (Gehan) test showed there was no significant difference between the two groups of RFS, MFS, and OS, while the diabetes group had a worse DFS than non-diabetes group (Wilcoxon p = 0.0047).

Conclusions: Patients with diabetes had a worse DFS than non-diabetes, but statistic tests did not show significant differences in RFS, MFS, and OS; further studies should be continue to find out the results in the future.