A quantitative study of late radiation effect on normal skin and subcutaneous tissues in human beings

Mathematical Models of Cell Survival After Ionizing Radiation

“…It is well known that each level of applied total dose will result in a given average level of tumor control and complications (Arcangeli et al 1974;Moore et al 1983;Thames et al 1982;Mah et al 1987). To accomplish the former, satisfactory dose distribution in the target volume can be achieved by maximizing the (total) minimum tumor dose and minimizing the maximum normal tissue dose through the selection of the appropriate irradiation factors.…”

“…4. For instance, it has been shown that acute reactions are very sensitive to variations of the latter parameter, while late reactions are mainly dependent on fraction size ( Arcangeli et al 1974). 3, but the total dose is lower and is subdivided into various fraction numbers.…”

Control of Dose Administered Once a Week and Three Times a Day According to Schedules Calculated by the CRE Formula, Using Skin Reaction as a Biological Parameter

“…These authors did not find any correlation between early and late skin tolerance but felt that "skin necrosis was well predicted by the NSD formula ." Several retrospective clinical studies indicate that the late consequences of irradiation cannot necessarily be predicted from the degree of early skin reaction, due to the fact that there is a difference in cell proliferation between epidermis and vascular connective tissue: damage to the former is responsible for early radiation effects, while damage to the latter is due to late radiation effects (1,4,7). On the other hand, early and late response to fractionated irradiation of the legs of rats (6,8) and mice (13) has been reported to show good correlation.…”

“…Early skin reactions were identical after irradiation daily and once a week, respectively, but were found to be significantly more pronounced after irradiation three times a day than after treatment once a day, corresponding to an overexposure of 7-10 % . (1) where T is the treatment time in days, N is the number of fractions, and d is the dose (rads) per fraction defined for 60CO. We have previously employed this formula to calculate the dose to bilateral parasternal fields in patients irradiated daily and twice a week following surgery for breast carcinoma (15).…”

The Effect of Tissue Expansion on Previously Irradiated Skin

“…26,31 The decline in the compliance of tissues damaged by chronic irradiation is probably related to the dosage and/or its chronicity. The detrimental effects of chronic irradiation damage re¬ sulting from a given dose are known to vary according to anatomic site because of such factors as surface tangentiality, the degree of adiposity, and yet-undefined factors among individuals.…”