Dacarbazine is primarily used in the treatment of metastatic malignant melanoma. It is administered intravenously and works by inhibiting DNA synthesis, which helps in slowing down or stopping the growth of cancer cells. Additionally, it is used in combination with other drugs for the treatment of Hodgkin's lymphoma. Its application in chemotherapy regimens has been significant in improving outcomes for patients with these types of cancers. The drug is often part of a multi-agent chemotherapy protocol to enhance its efficacy and reduce the risk of resistance.