Detection and Effect of Fluoride Level in the Neoplastic Tissue of Conventional Osteosarcoma Sub-Variants

الملخص

Conventional osteosarcoma is a primary intramedullary high grade malignant tumour in which osteoid is
synthesized by malignant cells even in small amount. WHO sub-classified conventional osteosarcomas into
three sub-variants osteoblastic, chondroblastic and fibroblastic depends on the neoplastic tissue produced by the
malignant osteoblasts. However, fluoride level in drinking water shows great variation between the costal-western
region of Libya (mean fluoride level 1.38ppm) and Cairo-Egypt (fluoride level 0.4ppm). Therefore, the aim of this
study is to detect analysis and compare the fluoride level in the neoplastic tissue of osteosarcomas from fluoridated
community (Libyan cases) and non-fluoridated community (Egyptian cases) as a case-control retrospective study
to evaluate the effect of fluoride on the malignant osteoblasts. 20 cases of osteosarcoma from each community in a
formalin-fixed paraffin embedded specimens and serial sections from the paraffin blocks for detection of fluoride
level in tumor tissue were included in this study.
The fluoride detection was determined using a combined Fluoride Ion Selective Electrode according to the Orion
method for fluoride detection after calibration with fluoride standards. The result of this study showed that in Libyan
cases, the mean of fluoride level in tumor tissue was 0.93 ppm with std. deviation 0.11 and histopathologically,
94% of osteosarcomas were ostoblastic, 6% chondroblastic and no fibroblastic variant was seen. In contrast
to Egyptian cases, the mean of fluoride level in tumor tissue was 0.0095 ppm with std. deviation 0.0070 and
histopathologically, 61% of cases were osteoblastic, 22% chondroblastic and 17% fibroblastic. Analysis of
variance used as a pair-wise test performed at the significance showed P value = 0.001 between two results. It is
concluded from this study that fluoride level and the osteoblastic variants of osteosarcoma are significantly higher
in areas where fluoride concentration in drinking water is higher than the normal limit.