Bone invasion in oral cancer patients: A comparison between Orthopantamograph, conventional computed tomography, and single positron emission computed tomography

Background and Objectives: One of the important factors in the pretreatment evaluation of patients with squamous cell carcinoma is the detection of the presence and extent of bone invasion by the tumor, which is significant for planning the therapy and determining the prognosis. Therefore, a study was undertaken with an objective to compare the accuracy and predictability of an Orthopantamograph (OPG), conventional Computed Tomography (CT), and Single Positron Emission Computed Tomography (SPECT) in the detection of bone invasion in squamous cell carcinoma patients scheduled to undergo surgery. Materials and Methods: A descriptive study was carried out on 15 patients with clinically and histopathologically diagnosed squamous cell carcinoma. OPG, conventional CT, and SPECT were carried out on all patients. Subsequently, the bone adjacent to the tumor was assessed histopathologically and served as a gold standard. The various imaging modalities were compared with the gold standard. Results: The study revealed that the tumor infiltration into the bone was positive in eight out of fifteen cases and seven were negative for bone invasion. OPG and conventional CT showed the presence of bone invasion in six out of eight cases with a sensitivity of 75% and a specificity of 100%. The positive predictive value for OPG was 100% and the negative predictive value was 78%. SPECT showed the presence of bone invasion in eight out of eight cases with a sensitivity of 100% and a specificity of 14.3%. The positive predictive value for SPECT was 57% and the negative predictive value was 100%. Conclusion: The present study showed that SPECT was highly sensitive, but with a very low specificity due to an increase in false positive values. However, OPG and conventional CT showed an acceptable degree of sensitivity and specificity