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Detailed guidelines from the NCCN for cancer treatment can be found at www.nccn.org.
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Use of cytotoxic drugs, hormones, antihormones, and biologic agents has become a highly specialized and increasingly effective means of treating cancer, with therapy administered and monitored by a medical oncologist or hematologist. Selection of specific drugs or protocols for various types of cancer is usually based on results of clinical trials. Increasingly, newer agents are being identified that target specific molecular pathways. Yet both initial and acquired drug resistance remains a challenge. Described mechanisms of drug resistance include impaired membrane transport of drugs, enhanced drug metabolism, mutated target proteins, and blockage of apoptosis due to mutations in cellular proteins (see Table 39–2 for suggested agents for various cancers).