Nilutamide is an antineoplastic hormonal agent primarily used in the treatment of prostate cancer. Nilutamide is a pure, nonsteroidal anti-androgen with affinity for androgen receptors (but not for progestogen, estrogen, or glucocorticoid receptors). Consequently, Nilutamide blocks the action of androgens of adrenal and testicular origin that stimulate the growth of normal and malignant prostatic tissue. Prostate cancer is mostly androgen-dependent and can be treated with surgical or chemical castration. To date, antiandrogen monotherapy has not consistently been shown to be equivalent to castration. The relative binding affinity of nilutamide at the androgen receptor is less than that of bicalutamide, but similar to that of hydroxuflutamide. Nilutamide competes with androgen for the binding of androgen receptors, consequently blocking the action of androgens of adrenal and testicular origin that stimulate the growth of normal and malignant prostatic tissue. This blockade of androgen receptors may result in growth arrest or transient tumor regression through inhibition of androgen-dependent DNA and protein synthesis. Nilutamide is used in combination with surgical castration for the treatment of metastatic prostate cancer involving distant lymph nodes, bone, or visceral organs (Stage D2). Nilutamide is sold under the brand names Nilandron (US), Anandron (CA)).