Synchronous Bilateral Breast Cancers.

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Bilateral breast cancer (BBC) incidence is rising due to improved survival and increased use of contralateral mammography.
• Understanding the epidemiological and tumor characteristics of BBC in India is essential.

Purpose of the Study:

• To define the epidemiological and tumor characteristics of bilateral breast cancer (BBC) in India.
• To evaluate the stage at diagnosis and pathological concordance in BBC.

Main Methods:

• Prospective analysis of 30 BBC patients (60 tumor samples) treated between January 2007 and March 2015.
• Classification of synchronous (SBC) and metachronous (MBC) bilateral breast cancers.
• Detailed analysis of patient demographics, tumor size, nodal status, histology, and receptor status.

Main Results:

• Median age of BBC patients was 66 years; most had SBC (n=28).
• Second tumors were often occult, detected by mammography, smaller, and less likely to have axillary metastasis.
• Infiltrating ductal carcinoma was common; most tumors were ER/PR positive with high concordance in histology and receptor status between breasts.

Conclusions:

• Early detection of the second tumor in BBC highlights the importance of contralateral screening.
• BBC is more common in older individuals and often estrogen-dependent.
• High pathological concordance between index and contralateral tumors suggests similar biological behavior.