Apoptosis in breast cancer.

Objective: To evaluate apoptotic rates on fine needle aspiration (FNA) samples of infiltrating duct carcinoma of the breast and to determine whether cytologic grading improved with consideration of the apoptotic rate in comparison with histologic grading.

Study Design: We studied 35 women who underwent mastectomy following an FNA diagnosis of infiltrating ductal carcinoma. Concordance between cytologic and histologic grades was calculated. Next, cytologic grades were considered with the apoptotic rates and compared with the histologic grades.

Results: An overall concordance of 82.9% was noted between the cytologic and histologic grading systems, with maximum concordance in grade 1 and minimum in grade 3 breast cancers. A highly significant difference in the apoptotic rates, as calculated on cytology, existed between the three histologic grades, indicating a significant increase in apoptosis with rising histologic grade. Applying multiple regression analysis, a significant improvement of cytologic grade with consideration of the apoptotic rate was observed.

Conclusion: Employing histologic grade as the yardstick, cytology was less sensitive for the purpose of grading breast ductal carcinoma. However, by considering the apoptotic rates, the sensitivity of cytologic grading significantly rose in relation to histologic grade. Larger studies are required to determine whether apoptosis can be incorporated into the existing cytologic grading systems to increase their sensitivity.