{Reference Type}: Case Reports {Title}: [Hypersensitivity to radiation therapy in a patient with tuberous sclerosis: biological considerations about a clinical case]. {Author}: Duchemann B;Duchemain B;Wong S;Baruch-Hennequin V;Rivera S;Quero L;Hennequin C; {Journal}: Cancer Radiother {Volume}: 17 {Issue}: 1 {Year}: Feb 2013 {Factor}: 1.217 {DOI}: 10.1016/j.canrad.2012.11.001 {Abstract}: A 61-year-old man, with a tuberous sclerosis, experienced severe acute reactions during a concomitant chemoradiotherapy regimen after 22Gy and one cycle of 5-fluorouracil-cisplatinum. He was treated for a cervical squamous cell lymph node of unknown origin. Grade 3 mucitis and epitheliitis were observed only in the irradiated fields and required the end of the radiotherapy. Tuberous sclerosis is characterized by a loss of the TSC2 function, with a permanent activation of the mTOR pathway. Logically, some kind of "radioresistance" should be observed. Increased radiosensitivity is paradoxical. This case illustrates how radiosensitivity is a complex phenomenon and clinically unpredictable. Efficiency of the protocols associations of mTOR inhibitors and radiotherapy should be carefully scrutinized.