SYNCHRONOUS BILATERAL BREAST CANCER RIGHT HER 2 POSITIVE AND LEFT HER 2 NEGETIVE- A CASE REPORT

Bilateral breast cancers (BBCs) represent 2–11% of breast cancers. The diagnosis of breast cancer at the same time or up to 6 months in both breasts is known as Synchronous bilateral breast cancer (s-BBC).^[1,2]In about 15% to 20% of breast cancers, the cancer cells make too much of a growth-promoting protein known as HER2. These cancers, known as HER2-positive breast cancers, tend to grow and spread more aggressively than HER2-negative breast cancers. Targeted drug therapy uses medicines that are directed at (target) proteins on breast cancer cells that help them grow, spread, and live longer. Anti-HER2 therapies (also called as HER2 inhibitors or HER2 targeted therapies) are a class of medicines used to treat all stages of HER2-positive breast cancer and certain HER2-low breast cancers.Trastuzumab is currently used sequentially after completion of anthracycline-based chemotherapy as a single agent or in combination with taxanes. In this case report we present a female 51 year old patient with synchronous bilateral breast cancer Left breast wasHER2 negative cT2N0M0, stage I and Right breast was HER2 positive cT2N2M0 stage Ia, both breast cancers were hormone receptor positive. The patient was administered six cycles of Inj. genexol-PM, Inj. carboplatin, Inj. pertuzumab, Inj. trastuzumab, Inj. Pegasta as NAC, Followed by bilateral radical mastectomy, patient showed a complete tumor reduction with residual node in right breast contrary to left breast which showed partial response. (Left breast ypT1N0 (sn)M0 and right breast ypT0N1aM0).