Anti-aromatase agents, also known as aromatase inhibitors, have strong scientific validation for their use in the treatment and management of certain types of breast lumps, particularly those associated with hormone-sensitive (estrogen receptor-positive) breast cancer. Aromatase is an enzyme responsible for the conversion of androgens to estrogens in the body. Elevated estrogen levels can promote the growth of some breast tumors. By inhibiting aromatase, these agents effectively reduce estrogen production, thereby limiting the stimulation and growth of estrogen-dependent breast tissue and tumors.

Multiple large-scale clinical trials and systematic reviews have established the efficacy of aromatase inhibitors such as anastrozole, letrozole, and exemestane in reducing recurrence rates and improving survival among postmenopausal women with hormone receptor-positive breast cancer. They are now standard of care in adjuvant therapy and sometimes in neoadjuvant settings. However, for benign breast lumps (such as fibroadenomas or cysts), there is limited evidence supporting their routine use, and these drugs are not commonly prescribed for non-cancerous breast lumps due to their side effect profile and lack of benefit in benign conditions.

In summary, aromatase inhibitors are backed by robust scientific evidence for hormone-sensitive malignant breast lumps, but not for benign lumps. Their use is carefully targeted based on the underlying hormonal biology of the breast condition.