Question

What reasons does high radiosensitivity of cells and tissues depend on?

Answer 1

The radiosensitivity of normal tissues and tumors varies considerably among individuals; for any group of patients given the same treatment, some will experience more severe reactions than others, and a small proportion will experience unacceptable late sequelae. The means of prospectively identifying in advance which individuals are particularly sensitive to radiation would be of tremendous benefit for clinical treatment. Unfortunately, no assay has been identified that would be suitable for routine clinical use. A group at The University of Texas M. D. Anderson Cancer Center found a link between late effects and the radiosensitivity of fibroblasts grown from skin biopsy specimens.52 West and colleagues53-56 in the United Kingdomfound that radiation therapy was less likely to produce local control of carcinoma of the cervix when the SF2 (i.e., fraction of tumor cells surviving 2 Gy) was greater than 0.55. However, no other studies have shown such promising results. Attempts to develop more rapid assays (e.g., assessments of chromosomal aberrations, DNA damage, cell growth rather than clonogenicity) have proved impractical for clinical use. Perhaps a more likely possibility for the future may be to screen patients who are to undergo radiation therapy for the presence of genes that may
confer radiosensitivity or radioresistance.

I hope my answer help to u and right