SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. It is estimated that approximately 310,720 new cases of breast cancer were diagnosed in 2024 and about 42,250 individuals will die of the disease, largely due to metastatic recurrence. Breast cancer is the second leading cause of cancer death in women, in the U.S.
Benign breast disease comprises approximately 75% of breast biopsy diagnoses, performed following abnormal mammographic findings. Benign breast disease can be, based on Dupont and Page, classified into nonproliferative diseases such as fibroadenomas, cysts, microcalcifications, fibrosis, apocrine, metaplasia, atrophy, fatty tissue necrosis, inflammatory tissue and ectasia, or proliferative disease which includes scar, hyperplasia, sclerosing adenosis, papilloma, adenosis, intraductal hyperplasia, lobular hyperplasia, benign Phylloides tumor, benign mesenchymal tumors, epithelial benign tumors, atypia, atypical ductal hyperplasia, and lobular intraepithelial neoplasia. Surgical biopsy specimens diagnosed as nonproliferative disease, proliferative disease without atypia, or atypical ductal hyperplasia are associated with long term risk of breast cancer. However, there is limited knowledge on breast cancer risk associated with percutaneously diagnosed benign breast diseases.
The researchers conducted this retrospective cohort study to estimate breast cancer risk among women diagnosed with benign breast disease (BBD) through percutaneous biopsies from 2002 to 2013. The study included 4,819 women with a median age of 51 years. The participants were followed from 6 months after biopsy until breast cancer diagnosis, or December 2021. Researchers compared breast cancer risk for women with benign breast disease with the female breast cancer incidence rates obtained from the Iowa Surveillance, Epidemiology, and End Results (SEER) program. The Primary outcome was overall breast cancer diagnoses, as well as diagnoses stratified as Ductal Carcinoma In Situ (DCIS) or invasive breast cancer. About 79% of women underwent core biopsy only, 10% underwent core biopsy and surgical excision and 11% underwent excisional biopsy only. Based on the most severe lesion identified, 50.8% of biopsy specimens were nonproliferative, 42% were proliferative disease without atypia, and 7.2% were atypical hyperplasia.
It was noted that women with benign breast disease diagnosed by percutaneous biopsies had a significantly higher overall breast cancer risk compared to the general population (Standard Incidence Ratio [SIR] = 1.95).
(The SIR is an estimate of the number of cancer cases in a given population compared to what might be “expected” based on a comparison with the cancer experience in a larger population.)
Breast cancer risk increased with the severity of benign breast disease, with SIR = 1.42 for nonproliferative lesions, SIR = 2.19 for proliferative disease without atypia and SIR = 3.91 for atypical hyperplasia. This pattern was comparable to surgical cohorts with benign breast disease.
The risk of breast cancer also increased with the multiplicity of lesions. Women with three or more foci of nonproliferative lesions had an SIR of 2.40, proliferative disease without atypia had an SIR of 3.72, and atypical hyperplasia had an SIR of 5.29, all compared with the general population.
Women with benign breast disease had an increased risk for both invasive breast cancer (SIR = 1.56) and Ductal Carcinoma In Situ (DCIS) (SIR = 3.10), compared to the general population.
The 10-year cumulative breast cancer incidence was 4.3% for nonproliferative lesions, 6.6% for proliferative disease without atypia and 14.6% for atypical hyperplasia, compared with the expected population cumulative incidence of 2.9%.
It was concluded from this study that there is an increased breast cancer risk among women with benign breast diseases diagnosed through percutaneous biopsies. The findings from this study emphasize the importance of considering both the severity and multiplicity of benign breast disease lesions for improved breast cancer risk stratification. The authors also suggest that advancements in digital imaging and computational pathology approaches may enhance future analysis of benign breast disease biopsy specimens, for better risk prediction.
Benign Breast Disease and Breast Cancer Risk in the Percutaneous Biopsy Era. Sherman ME, Vierkant RA, Winham SJ, et al. JAMA Surg. 2024;159:193-201.
