Hexamethylmelamine (also known as altretamine) is primarily used in the treatment of ovarian cancer, particularly for persistent or recurrent cases. It functions as an alkylating-like agent, which interferes with the DNA in cancer cells, preventing their growth and proliferation. This makes it a valuable component in chemotherapy regimens, especially for patients who may not respond well to other treatments. It has been explored in combination therapies with other chemotherapeutic agents to enhance efficacy and reduce drug resistance. While its use is mainly for ovarian cancer, investigational applications in other cancers such as lung and breast have been studied. Its application is carefully monitored due to potential side effects including nausea, vomiting, leukopenia, and fatigue, and it is typically administered under strict medical supervision.