The Journal of Bucharest College of Physicians and the Romanian Academy of Medical Sciences

Bone Remodeling Regulators in Central Giant Cell Granuloma: a Study of RANK and Osteocalcin Expression

Authors

Background: Giant cell granulomas of the jaws are reactive bone lesions that impact bone remodeling. The specific pathophysiology was unclear, although osteoclast-type giant and stromal cells were suggested as major modulating factors. Aim of the study: The study aims to determine the levels of two bone regulators, RANK and osteocalcin, in central giant cell granuloma and their correlation with aggressive behavior. Material and method: Twenty-one formalin-fixed paraffin-embedded tissue blocks of central giant cell granuloma were collected from laboratory archives and have been made based on clinical and histologic findings. Polyclonal antibodies for RANK and osteocalcin (OC) were used for immunohistochemical (IHC) procedures, and their expression and staining-intensity-distribution (SID) scores were analyzed.
Results: Non-aggressive cases showed slightly higher RANK expression, but this was not significant. However, the SID score was significantly higher in non-aggressive cases (P=0.02088). A strong correlation between RANK expression and SID scores was seen in aggressive CGCG (r=0.728, P=0.026). OC expression was significantly higher in aggressive CGCG (30.16%) compared to non-aggressive CGCG (8.58%) (P=0.0232). The SID score for OC also showed a significant difference (P=0.018), with a strong association between OC expression and SID scores in both non-aggressive (r=0.993, P<0.001) and aggressive CGCG (r=0.855, P=0.003).
Conclusion: RANK and osteocalcin expression can differentiate between aggressive and non-aggressive central giant cell granulomas. They provide significant predictive data for clinical decision-making and patient outcomes, highlighting their importance in central giant cell granuloma identification and treatment.