Anticancer chemotherapy agents include all of the following EXCEPT:
Anticancer agents include alkylating agents, antitumor antibiotics, antimetabolites, and plant alkaloids. Antimetabolites are cell-cycle specific agents that have their major activity in the S phase of the cell cycle. These drugs are most effective in tumors that have a high growth fraction, and include folate antagonists, purine antagonists, and pyrimidine antagonists.
Approved strategies for cancer chemoprevention include all of the following EXCEPT:
The systemic or local administration of therapeutic agents to prevent the development of cancer, called chemoprevention, is being actively explored for several cancer types. In breast cancer, the NSABP Breast Cancer Prevention Trial demonstrated that tamoxifen administration reduces the risk of breast cancer by one-half and reduces the risk of estrogen receptor-positive tumors by 69% in high-risk patients. Therefore, tamoxifen has been approved by the FDA for breast cancer chemoprevention. The subsequent NSABP P-2 trial demonstrated that raloxifene is as effective as tamoxifen in reducing the risk of invasive breast cancer and is associated with a lower risk of thromboembolic events and cataracts but a nonstatistically significant higher risk of noninvasive breast cancer; these findings led the FDA to approve raloxifene for prevention as well. Several other agents are also under investigation. Celecoxib has been shown to reduce polyp number and polyp burden in patients with FAP, which led to its approval by the FDA for these patients. In head and neck cancer, 13-cis-retinoic acid has been shown both to reverse oral leukoplakia and to reduce second primary tumor development.