Donald R. Eisert

Irradiation for bronchial carcinoma: Reasons for failure. I. Analysis of local control as a function of dose, time, and fractionation†

Radiation therapy is the only potentially curative form of therapy for patients with carcinoma of the lung who are not surgical candidates. Previous studies have evaluated response by evaluating survival. Evaluation of local control of disease is essential if one is to understand and modify therapeutic approaches in an effort to increase survival. Clinical data are presented on 197 patients with primary epithelial tumors of the lung. An analysis of local control data is presented using the concept of nominal standard dose (NSD). If local failure is to occur, it is manifest by 15 months. Survival is affected by the ability or inability to achieve local control. Above a dose of 1450 ret, no correlation between increasing ret dose and increasing local control is observed.

Current radiosurgery practice : results of an astro survey

PURPOSE Although there is increasing interest in radiosurgery, little quantitative data regarding current patterns of radiosurgery practice are available. We developed a radiosurgery questionnaire to obtain information on radiosurgery practice. METHODS AND MATERIALS We distributed the questionnaire to the entire membership of the American Society of Therapeutic Radiology and Oncology in early 1993. Responses were obtained from 74 facilities that practice radiosurgery, corresponding to over 6000 treatments carried out since 1983 by 135 radiation oncologists and 130 physicists. RESULTS Most respondents were found to work within a multidisciplinary team, consisting of the following specialists (average hours devoted per patient on day of treatment in parentheses): radiation oncologist (3.8), neurosurgeon (3.2), physicist (6.1), radiologist (0.7), nurse (2.7), other (3.0). On average, neurosurgeons and nurses who perform Gamma Knife radiosurgery devote significantly more time-per-patient on the day of treatment than their peers who perform linac radiosurgery. On average, less experienced radiation oncologists and physicists (< or = 24 months experience, or < or = 50 patients treated) devote significantly more time-per-patient on the day of treatment than their more experienced peers. Although there are many more linac radiosurgery facilities than Gamma Knife facilities, on average the number of patients treated per month per facility is significantly larger at the latter. On average, follow-up responsibilities are nearly equally shared by radiation oncologists and neurosurgeons, except at Gamma Knife facilities, where neurosurgeons assume a larger percentage of follow-up responsibility. The percentages of patients treated at linac facilities for metastases or primary CNS malignancy are larger than the corresponding percentages at Gamma Knife facilities; the opposite is true for arteriovenous malformation, acoustic neuroma, and meningioma. CONCLUSION Current radiosurgery practice usually involves a team approach, with participation of specialists from radiation oncology, neurosurgery, physics, radiology, and nursing. The average number of M.D. and Ph.D. hours required per treatment on the day of radiosurgery is high.

Irradiation of bronchial carcinoma —II Pattern of spread and potential for prophylactic irradiation

Abstract From January 1971 through June 1975, 197 patients who had inoperable or unresectable carcinoma of the lung without evidence of distant spread, received definitive irradiation with curative intent. The pattern of spread in these patients is analyzed according to the site and timing of the first new manifestation of disease after initiation of irradiation. Nineteen patients are still free of evidence of cancer. Equal proportions of the remaining 178 patients failed locally or at distant sites. The clinical diagnosis of metastasis was made most frequently in the ipsilateral or contralateral lung, bones, brain and liver. Aggressive irradiation of brain metastases can prolong useful life substantially. Survival should improve by prevention of the clinical expression of brain metastases by irradiation when they still are subclinical. Because of the high risk of metastasis and the potential to increase survival, prophylactic irradiation to the entire thorax and the liver could be studied for bronchial carcinoma of all cell types.