Dose fractionation and biological optimization in carcinoma of the uterine cervix.

Data of the literature concerning the dose, fractionation, and elapsed treatment time, all parameters critical to local pelvic tumor control in patients treated with irradiation for carcinoma of the cervix are analyzed. Total dose, dose rate, and biological dose optimization are important parameters that correlate with treatment sequelae. Elapsed treatment time does not. As for the use of brachytherapy, performance of all intracavitary insertions within the first 4.5 weeks of treatment correlated with better tumor control in stages IB, IIA and IIB with low dose rate (LDR) brachitherapy. Careful attention to biological parameters is critical to optimize treatment schemas and outcome of radiation therapy. When combinations of irradiation with either surgery or chemotherapy are used, special attention must be paid to tolerance doses of organs at risk, to minimize sequelae without compromising tumor control.