In recent years, cisplatin-based chemotherapy given concurrent with radiation has emerged as the new standard of care for treating locally advanced cervical cancer.
Adding chemotherapy has several potential advantages. Several large randomized clinical trials have shown the effectiveness of chemoradiation in the treatment of cervical cancer. The National Cancer Institute (NCI) underscored the importance of these studies by issuing a rare clinical announcement suggesting that "strong consideration should be given to incorporation of concurrent chemotherapy with radiation therapy in women who require radiation therapy for the treatment of cervical cancer."4
Biology of platinum-based chemoradiation
In theory, combining chemotherapy with radiation offers at least two advantages. First, chemotherapy can enhance the radiation's ability to kill local cervical tumors. Second, the combination is able to eradicate occult metastases outside the radiation field that would otherwise be untreated.
Tumor cytotoxicity intensifies when cisplatin is combined with radiation therapy, both in vitro and in vivo. One proposed explanation for this effect is that the drug stops cancer cells from repairing sublethal damage caused by radiation; another is that it preferentially sensitizes hypoxic cells. Animal studies suggest that the therapeutic gain is greatest when cisplatin is administered immediately before (rather than after) radiation, and that the combination of cisplatin and radiation is supra-additive regardless of whether the drug is given in a single dose before or in multiple doses during radiation.5