Chemotherapy during pregnancy

The diagnosis of pregnancy-associated cancer is a dramatic event that poses difficult dilemmas for the pregnant patient, her family, and the medical team. The main challenge is to treat the patient with the optimal anticancer regimen without harming the developing fetus. This issue is further complicated; because of the lack of large prospective studies, the available experience regarding the treatment of pregnancy-associated cancer is based mainly on small, retrospective studies and case reports. Almost all chemotherapeutic agents are teratogenic in animals and for some drugs, only experimental data exist [1]. Furthermore, because cytotoxic drugs are usually not administered as a single drug, most human reports arise from exposure to multi-drug regimens, making it difficult to estimate the direct effect of each drug [2]. Decisions about the management of pregnancy-associated cancer should be made individually for each patient after careful consideration of possible treatment alternatives as well as maternal and fetal risks. However, when there is a clear risk to the pregnant patient, her safety may supersede fetal risk. In this chapter, we critically review the current information and controversies regarding different aspects of the administration of chemotherapy during pregnancy. We also review the available experience with the most common anticancer regimens as well as each chemotherapeutic agent. Pharmacology Due to their relatively low molecular weight, most cytotoxic agents can cross the placenta and reach the fetus [1,3]. The pharmacology of the various anticancer drugs may be altered by the normal physiological changes that occur during pregnancy such as increased plasma volume, enhanced renal and hepatic elimination, and decreased albumin concentration. These changes may decrease active drug concentrations. Dosing similar to that of nonpregnant women of the same weight may lead to undertreatment of patients with pregnancy-associated cancer [3].