Cellular radiosensitivity of patients with different types of neurofibromatosis

Abstract Skin fibroblast cell strains were developed from nine Saudi patients with different types of neurofibromatosis (NF) and nine healthy subjects (controls), and their radiosensitivity was compared following chronic exposure to γ-radiation at a dose rate of 0.0076 Gy/min (1 Gy=100 rads). Cells from both normal appearing skin and cafe-au-lait spots of the different NF patients (7 out of 9) clearly showed increased radiosensitivity, with D 10 (dose resulting in 10% survival) values of 2.0–4.4 Gy for the former and 3.0–4.8 Gy for the latter, compared to the normal controls (with D 10 values of 6.1–10.6 Gy). These data provide further evidence of an association of enhanced cellular sensitivity to chronic irradiation with NF regardless of the classes they belong to. Hypersensitivity to specific carcinogens may, thus, be a factor responsible for the increased propensity to cancer in these patients.