antineoplastic

Antineoplastic agents are drugs used to treat malignant neoplasms by inhibiting the growth and spread of cancer cells. The term covers a range of agents that can be cytotoxic, meaning they kill dividing cells, or cytostatic, meaning they slow cell growth. They are employed as systemic therapies and can aim for cure, disease control, or palliation. Antineoplastics include traditional chemotherapy, targeted therapies, hormonal treatments, and immunotherapies.

Traditional cytotoxic chemotherapy comprises several classes that disrupt DNA replication, repair, or cell division. Alkylating agents damage DNA and are widely used; platinum compounds form DNA crosslinks; antimetabolites inhibit nucleotide synthesis; microtubule inhibitors disrupt mitosis; and topoisomerase inhibitors impair DNA topology. Examples include cyclophosphamide, cisplatin, methotrexate, 5-fluorouracil, paclitaxel, and doxorubicin.

Targeted therapies and immunotherapies exploit specific features of cancer cells or the immune system. Tyrosine kinase inhibitors such as imatinib block oncogenic signaling; monoclonal antibodies like rituximab target cell-surface proteins; checkpoint inhibitors such as pembrolizumab release immune brakes to attack tumors; hormonal therapies such as tamoxifen or aromatase inhibitors interfere with hormone signaling in hormone-sensitive cancers.

Administration and planning often involve combination regimens and may be used in neoadjuvant, adjuvant, or palliative settings. Treatments can be given orally, intravenously, intrathecally, or intraperitoneally, with dosing tailored to cancer type, stage, and patient health.

Adverse effects vary by drug class but commonly include myelosuppression, nausea, mucositis, alopecia, neuropathy, and organ-specific toxicities. Long-term risks may include secondary malignancies. Effective use requires careful monitoring, supportive care, and management of toxicity to maximize benefit.