Revision 1

Accepted · first revision · record

Title: Physical markers of individual radiosensitivity
Plain: A minority of patients suffer unusually severe side effects from standard radiotherapy doses. There is no reliable test to find them in advance.
Precise: Identify an assay predicting severe normal-tissue reaction, defined as grade 3 or higher toxicity, before treatment, with sensitivity and specificity sufficient for clinical use. Candidate physical and cellular measures: residual DNA double-strand break foci at 24 h, chromosome aberration yield per 100 rad in lymphocytes, and apoptosis fraction after ex vivo irradiation. An answer names a validated assay with its operating characteristics.
Settled by: Prospective blinded validation of a candidate assay against observed toxicity in a treated cohort.
Kind: well-posed
Answer type: identification
References: (empty)
Literature status: open
Status note: A lymphocyte apoptosis assay was validated prospectively for late breast fibrosis in 2015 (Azria et al., EBioMedicine), with discrimination too modest for routine clinical use.
Posed since: 1990