The intrinsic radiosensitivity of normal and tumour cells.
OBJECTIVE
To examine whether in vitro measurements of normal and tumour cell radiosensitivity can be used as prognostic factors in clinical oncology.


METHODS
Stage I-III cervix carcinoma patients were treated with radical radiotherapy with a minimum of 3 years' follow-up. Lymphocyte and tumour radiosensitivities were assayed using, respectively, a limiting dilution and soft agar clonogenic assay to obtain surviving fraction at 2 Gy (SF2). The results were related, in an actuarial analysis, to late morbidity assessed using the Franco Italian glossary.


RESULTS
Patients with radiosensitive lymphocytes had a significantly increased risk of developing late complications (n = 93, p = 0.002). Increasing tumour radiosensitivity was associated with an increased risk of morbidity (n= 113, p=0.032). A significant correlation was found between fibroblast and tumour cell radiosensitivity (r=0.57, p=0.03), but a weak inverse association was found between lymphocyte and tumour cell radiosensitivity (r= -0.32, p=0.03). Patients with radiosensitive lymphocytes and tumour cells had higher levels of late complications than those whose cells were radioresistant.


CONCLUSIONS
The work described highlights the importance of cellular radiosensitivity as a parameter determining the clinical response to radiotherapy.
West
C M
CM
CRC Sections of Genome Damage and Repair, Paterson Institute for Cancer Research, Manchester, UK.
Davidson
S E
SE
Elyan
S A
SA
Swindell
R
R
Roberts
S A
SA
Orton
C J
CJ
Coyle
C A
CA
Valentine
H
H
Wilks
D P
DP
Hunter
R D
RD
Hendry
J H
JH
D002277:Carcinoma / Q000401:mortality / Q000532:radiotherapy*; D003114:Colony-Forming Units Assay; D005260:Female; D005347:Fibroblasts / Q000528:radiation effects*; D006801:Humans; D008214:Lymphocytes / Q000528:radiation effects*; D009367:Neoplasm Staging; D011836:Radiation Tolerance; D016019:Survival Analysis; D002583:Uterine Cervical Neoplasms / Q000401:mortality / Q000532:radiotherapy*