The effects and significance of radiotherapy on biochemical markers of bone metabolism in patients with nasopharyngeal carcinoma.

PURPOSE: To detect the changes and evaluate the effect of radiotherapy in patients with nasopharyngeal carcinoma on biochemical markers of bone metabolism on the jaw bones. METHODS: Twenty two patients with nasopharyngeal carcinoma receiving radiotherapy were included in this study. Concentration of serum BAP,TRACP-5b prior to radiotherapy, after 30Gy and 50Gy of radiotherapy were detected by enzyme-linked immunosorbent assay(ELISA); Concentration of urine Ca was assayed by arsenazo M spectrophotometric and the urine creatinine (Cr) was determined by carbazotic acid method; Data were compared by paired t test and Mann-Whitney nonparametric test using SPSS17.0 software package. RESULTS: The serum BAP decreased with increase of radiation dose. Compared with serum BAP prior to radiotherapy, there was a significant decrease in patients after 50Gy of radiotherapy(P<0.05); The serum TRACP-5b was not significantly changed before and after radiotherapy (P>0.05); Ionizing radiation-induced decrease in the urinary Ca/Cr was found, and there was significant difference not only between the dose of OGy and 50Gy but also between the dose of OGy and 30Gy (P<0.05). CONCLUSION: Radiation can inhibit the activities of jaw bone,the biochemical markers of bone metabolism in BAP and U Ca/Cr can reflect the effects of radiation on jaw bone metabolism. Supported by Science and Technology Research Program of Guangdong Province (2009B030801186) and Research Project of Bureau of Science and Technology of Zhuhai City(2007-46). [ABSTRACT FROM AUTHOR]