Effects of obesity on breast cancer stage at diagnosis in Korean women.

This study was carried out to test the hypothesis that palpation for lumps may be more difficult in large breasts than in small breasts, resulting in a delay in the detection and diagnosis of breast cancer, and to determine whether this hypothesis is confirmed in Asian women. Of 833 new breast cancer patients registered in the Daegu Cancer Registry in 1997-1999, 579 were used in the final data analysis, after excluding patient records containing many missing data on study variables related with cancer staging. There was no difference in means of body mass index (BMI) according to tumour, either in all cases or in those under 49 years of age. In the 50+ age group, the means+/-standard deviations of BMI of T1, T2 and T3 were 23.7+/-2.8, 24.2+/-3.0, and 26.2+/-4.3, respectively (P=0.01). In univariate logistic regression of tumour characteristics with BMI, no statistically significant odds ratios were found either by continuous or quartiles of BMI. In conclusion, these results suggest that the hypothesis is partially confirmed in Korean breast cancer patients and further studies are needed to clarify the relationship between BMI and tumour stage at diagnosis.