Simplified irradiation dosimetry in carcinoma of the cervix (external irradiation and one radium insertion).

Gynecologic radiation oncologists have long desired a single unit by which radiation doses to specific reference points in the pelvis can be summed. The Patterns of Care Studies, Marcial's 1976 report to the Conference on Radiation Oncology of the American Cancer Society, and other radiation oncologists advise summed doses to Point A, Point B, or the pelvic side wall. Since there is a difference in the biologic effect of high intensity, long time interval teletherapy and low intensity, short time interval brachytherapy, the rad dose obtained from each modality cannot be simply added. Ellis and Sorenson in the Nominal Standard Dose (NSD) concept have described radium conversion factors that can be used to normalize brachytherapy rads at selected reference points to equivalent teletherapy rad. The two rad doses can then be summed. A simple method found useful in 50 cases of carcinoma of the cervix, and used with a computer or readily available reference tables and with any radium system, is described and discussed. Further clinical uses of the method are suggested.

Low-dose preoperative radiation therapy in carcinoma of the supraglottic larynx.

Seventy patients treated for all stages of carcinoma of the supraglottic larynx were analyzed retrospectively. A preoperative dose of 3,000--3,600 rads was given in 15 to 18 treatments over three to four weeks and surgery carried out four weeks later. The 5-year disease-free survival rates were approximately 75% in patients with early disease and 50% in those with more advanced disease. Survival with early disease was similar to that achieved by radical radiotherapy alone, while survival with advanced disease was similar to that achieved by surgery alone. These results suggest that low-dose preoperative irradiation is of limited value.