UNASSIGNED: There is considerable variation in the level of @entity137 @entity1 experience for a given dose of radiotherapy, which is associated with differences in underlying individual normal tissue radiosensitivity. A number of syndromes have a large effect on clinical radiosensitivity, but these are rare. Among @entity8468 @entity1 , variation is less extreme, but equivalent to a   20% variation in dose. Thus, if individual normal tissue radiosensitivity could be measured, it should be possible to optimise schedules for individual @entity1 . Early investigations of in  vitro cellular radiosensitivity supported a link with tissue response, but individual studies were equivocal. A lymphocyte apoptosis assay has potential, and is currently under prospective validation. The investigation of underlying genetic variation also has potential. Although early candidate gene studies were inconclusive, more recent genome-wide association studies are revealing definite associations between genotype and @entity137 and highlighting the potential for future genetic testing. Genetic testing and individualised dose prescriptions could reduce @entity137 in radiosensitive @entity1 , and permit isotoxic dose escalation to increase local control in radioresistant individuals. The approach could improve outcomes for half the @entity1 requiring radical radiotherapy. As a number of @entity1 - and treatment-related factors also affect the risk of @entity137 for a given dose, genetic testing data will need to be incorporated into models that combine @entity1 , treatment and genetic data.

Incorporating Genetic Biomarkers into Predictive Models of Normal Tissue XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity'] @entity8468 :: ('OMIM:600791', 'Disease') :: ['non-syndromic']
@entity137 :: (MESH:D064420,Disease) :: ['Toxicity']
