Per oral vitamin B12 replacement therapy after gastrectomy and its optimal dose (retrospective study) and our protocol of a prospective clinical trial.

Abstract

338 Background: Postgastrectomy vitamin B12 deficiency is common metabolic sequel and worsens the quality of life of gastric cancer survivors. Recently, oral vitamin B12 replacement is reported. Therefore, we investigated retrospectively the efficacy of oral vitamin B12 replacement for gastric cancer patients with vitamin B12 deficiency after total gastrectomy. Methods: We reviewed 73 patients with gastric cancer who underwent total gastrectomy and were treated vitamin B12 replacement. Patients were consisted of 56 males and 17 females and median age was 70 y/o. We investigated initial treatment of vitamin B12 replacement and improvement of vitamin B12 deficiency. Results: Initial treatment of vitamin B12 replacements were intramuscular injection for 42 patients, per oral replacement for 28 patients and intravenous injection for 3 patients. Finally, all patients were treated with per oral replacement and the serum vitamin B12 levels became within normal range. Final vitamin B12 doses of replacement therapy were 500 µg of 20 out of 73 pts, respectively. Conclusions: Vitamin B12 replacement therapy should be necessary and continued. According to our results, one vitamin B12 tablet a day is enough. The vitamin B12 deficiency symptoms could be prevented. 500 micrograms vitamin B12 replacement orally is maybe effective and necessary. Our prospective clinical protocol (UMIN000030727): In this study, an oral vitamin B12 preparation (1500 μg/day, administered daily) was set as the control treatment, and a specific clinical trial was started to determine whether 500 μg/day daily administration would be sufficient for replacement therapy. Clinical trial information: UMIN000030727.