Serum protein changes in women with early breast cancer.

Lowered serum concentrations of albumin, IgG, IgM, and transferrin have been identified preoperatively in a population of otherwise healthy white women over age 40 with early stage breast cancer. Definition of low values for each of the four serum proteins has been arrived at via comparison with age-matched controls, consisting of disease-free women and women with benign breast lesions. Thus defined, low values for the individual serum proteins have been found to occur in malignant/control study subjects at the following frequencies: albumin 68%/4.7% (P less than 0.0001); IgG 56%/21% (P less than 0.02); IgM 59%/19% (P less than 0.001), and transferrin 50%/4.7% (P less than 0.0001). Among the relevant historical and pathologic data evaluated in addition to the presence or absence of malignancy, only age has been found significant in influencing serum protein concentrations, and this has been taken into account in analyzing results. Forty-four percent of study subjects subsequently found to have breast cancer have low concentrations of at least three of the four discriminant proteins simultaneously in the pre-operative sample. None of the controls have these findings. Twenty-nine percent of women with a malignant breast lesion and 9% of controls have simultaneously low concentrations of two of the four discriminant proteins. Using these measurements of serum proteins it thus becomes possible to assign risk of malignancy when a woman is found to have a breast mass.