Potential thiamine deficiency in elderly patients with gastrointestinal cancer undergoing chemotherapy .

Gastrointestinal cancer and its treatment using fluorouracil-based anticancer agents are risk factors for thiamine deficiency (TD). Therefore, we aimed to determine the prevalence of TD among elderly patients with gastrointestinal cancer undergoing chemotherapy. We retrospectively reviewed the medical records of 12 elderly patients with gastrointestinal cancers who underwent chemotherapy. Median serum thiamine level was 22.5 ng/mL (range, 17 - 42 ng/mL). Four patients (33.3%) exhibited TD (< 20 ng/mL). We found that the prevalence of TD among elderly patients with gastrointestinal cancer undergoing chemotherapy was high. For these patients, careful monitoring of thiamine levels is warranted because TD may not produce overt clinical symptoms.