Background: Watering eyes is a common late adverse event associated with S-1 chemotherapy; however, the frequency and predictive factors are not known.
Methods: This study included 304 consecutive gastric cancer patients treated with adjuvant S-1 monotherapy for 1 year at Shizuoka Cancer Center. We retrospectively evaluated the frequency of watering eyes, and explored other nonhematological adverse events during the first course of S-1 monotherapy which could become predictive factors for watering eyes.
Results: The severest grade of watering eyes during S-1 monotherapy was grade 2 in 41 patients (13.5 %) and grade 3 in 36 patients (11.8 %). The median time to onset of grade 2 and grade 3 watering eyes was 82 days (range 6-344 days) and 249 days (range 84-653 days), respectively, and the median cumulative S-1 dose at the onset of grade 2 and grade 3 watering eyes was 4174 mg/m(2) (range 491-16,095 mg/m(2)) and 10,243 mg/m(2) (range 4943-16,341 mg/m(2)), respectively. Multivariate analysis showed that anorexia (odds ratio 2.37, P = 0.008), oral mucositis (odds ratio 3.86, P = 0.0003), skin hyperpigmentation (odds ratio 3.84, P = 0.0001), and rash (odds ratio 3.76, P = 0.01) observed during the first course were significantly associated with watering eyes.
Conclusion: The risk of watering eyes was higher in patients who also had anorexia, oral mucositis, skin hyperpigmentation, or rash during first course of S-1 monotherapy than in those without them.
Keywords: Adverse event; Chemotherapy; Gastric cancer; S-1; Watering eyes.