Vitamin B12 Deficiency Anemia after Total Gastrectomy in Patients with Stomach Cancer

Ko, Yun Woong; Min, Jin Sik; Suh, Hyung Chan; Cho, Joon Sik; Lee, Seok; Chong, So Young; Yoo, Nae Choon; Min, Yoo Hong; Hahn, Jee Sook

Abstract

OBJECTIVES
We attempt to find out the decremental character of serum vitamin B12 level and features of patients with vitamin B12 deficiency anemia occurring earlier than 4 years after total gastrectomy.
Methods
We studied 91 patients who underwent total gastrectomy and select 59 patients who evaluate serum vitamin B12 level within 4 years after total gastrectomy to characterize the features of vitamin B12 deficiency anemia group occurring earlier than 4 years after the operation.
RESULTS
1) In 91 patients, the mean postoperative duration is 31.9(range: 0-135) months and mean serum vitamin B12 level 158.9(total 159 times, range: 20.0-806.2) pg/mL. Correlation equation is y=403.30 x e-0.09x+175.93 x e-0.02 x (r2=0.804). The postoperation duration that serum vitamin B12 level falls below 200 pg/mL is 20 months. 2) Among 59 patients, there were 20 cases of vitamin B12 deficiency anemia group(Group I), 21 cases of vitamin B12 deficiency(Group II) and 39 cases of non-vitamin B12 deficiency group(Group III). Preoperation symptom dura tion in Group I was longer than that in Group II(18.2 vs 9.6 weeks, p<0.01). Group I and Group II showed lower serum vitamin B12 level than Group III(126.7 & 96.0 pg/mL vs 330.4 pg/mL, p<0.01). 3) Eleven cases had associated diseases(9 alcoholics and 2 liver cirrhosis) with vitamin B12 deficiency anemia and these disease had significant influence on the incidence of vitamin B12 deficiency anemia(p<0.01) within 4 years. Among the 30 cases who could measure iron profile, 10 patients had an iron deficiency anemia. There was a higher incidence of vitamin B12 deficiency anemia in iron deficiency anemia group(7/10, 70%) than that in non iron deficiency anemia group(7/20, 35%) but no sta tistical significance(p=0.12). 4) Although anti-cancer chemotherapy did not have a significant influence on the incidence of vitamin B12 defi ciency anemia, vitamin B12 level in anti-cancer chemo therapy group was higher than that in non-chemotherapy group(201.83 vs 127.66 pg/mL, p=0.01) at similar mean postoperation duration(27.8 vs 27.7 months, p=0.97). 5) The independent predictor of vitamin B12 deficiency anemia within 4 years were associated disease(p=0.002) and preoperation symptom duration(p=0.004).
CONCLUSION
Red cell indices such as Hb or MCV did not have any clinical significances in predicting the development of vitamin B12 deficiency. To prevent vitamin B12 deficiency anemia and promote better quality of life in total gastrectomized patients with stomach can cer, careful monitoring of serum vitamin B12 level and re placement therapy should be necessary at least 20 months after operation, especially in patients with associated disease and longer preoperation symptom duration.