Abstract
Biological characteristics of breast cancer in obese patients were investigated in comparison with non-obese patients. 134 patients with breast cancer were divided into three categories; thin, normal and obese based upon the height and weight. Five-year survival rate was 55. 6% in the obese patients, whereas it was 79. 9% in the non-obese patients including thin and normal subjects. A cause for unfavorable prognosis in the obese patients with breast cancer was clinically and histologically investigated. It was found that in the obese patients primary tumor, regional lymph node engorgement and clinical stage were relatively advanced, scirrhous carcinoma was predominant (46%), tumor margin was more infiltrative (γ type 64%), the incidence of vascular involvement was high (73%), lymph node metastasis was also frequent (58%) and nuclear grade was low.