Which medication is commonly prescribed to suppress tumor growth in cases of breast cancer?

Tamoxifen is commonly prescribed to suppress tumor growth in cases of breast cancer due to its specific action as a selective estrogen receptor modulator (SERM). Breast cancer cells can depend on estrogen for growth, and Tamoxifen works by binding to estrogen receptors on these cells, blocking estrogen from activating them. This blockage can slow down or even stop the growth of tumors that are estrogen-receptor positive, which is a common characteristic in many breast cancers.

While other medications mentioned, such as Adriamycin (doxorubicin), Paclitaxel, and Cyclophosphamide, are also used in the treatment of breast cancer, they function differently. Adriamycin is an anthracycline that inhibits DNA synthesis leading to cancer cell death, Paclitaxel disrupts the microtubule function necessary for cell division, and Cyclophosphamide is an alkylating agent that interferes with DNA replication. These drugs may be part of chemotherapy regimens but do not specifically target the estrogen pathway the way Tamoxifen does. Therefore, Tamoxifen is the preferred choice for hormone-receptor-positive breast cancers, illustrating its role in managing this condition effectively.