Goserelin is primarily used in the treatment of hormone-sensitive cancers, such as prostate cancer in men and breast cancer in women. It works by reducing the production of certain hormones, like testosterone and estrogen, which can fuel the growth of these cancers. In prostate cancer, it helps slow tumor progression and manage symptoms. For breast cancer, it is often used in premenopausal women to suppress estrogen levels, thereby inhibiting cancer growth. Additionally, goserelin is employed in the management of endometriosis and uterine fibroids, where it helps alleviate pain and reduce the size of abnormal tissue growths by lowering estrogen levels. It is also used in assisted reproductive technologies to control ovulation timing during fertility treatments.