Accuracy of cone-beam computed tomography for the evaluation of mandible invasion by oral squamous cell carcinoma

Computed Tomography in Predicting the Mandibular Involvement by Oral Cancer, a Retrospective Study

Despite several newer advancements in imaging technology, no new investigative modality has been introduced to clinical practice in the recent times that is accurate and yet cost-effective. As a result, the majority of cancer centers across the globe rely on computed tomography to diagnose and estimate bone involvement in oral cancer. Here, we evaluated the reliability of computed tomography in predicting the mandibular invasion in our cohort of oral cancer patients who had undergone mandibulectomy. In this retrospective study, conducted at a tertiary cancer care facility, the patients of oral cancer who were operated at our center between 1st October 2018 and 30th September 2020 were considered. The sensitivity, specificity, and positive and negative predictive values of the computed tomography in predicting bone involvement were calculated, and the survival analysis was performed to understand the implication of mandibular involvement on survival. The sensitivity and specificity of computed tomography in detecting bone involvement was around 77.9% and 76.7%, respectively, which were comparable with the other reports. In our series, only 30% of the resected mandible were involved by the disease. However, pathological involvement of the mandible did not affect the overall survival on univariate and multivariate analysis, but the presence of pathological positive cervical lymph nodes affected the survival. The outcome of our study suggests that the conservative mandibulectomy could be a sound oncological procedure particularly in those cases with no frank erosion of the mandible on computed tomography.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-025-05321-x.

Performance of cone-beam computed tomography (CBCT) in comparison to conventional computed tomography (CT) and magnetic resonance imaging (MRI) for the detection of bone invasion in oral squamous cell cancer (OSCC): a prospective study

BACKGROUND

Oral squamous carcinoma (OSCC) is often diagnosed at late stages and bone erosion or invasion of the jawbone is frequently present. Computed tomography (CT) and magnetic resonance imaging (MRI) are known to have high diagnostic sensitivities, specificities, and accuracies in detecting these bone affections in patients suffering from OSCC. To date, the existing data regarding the impact of cone-beam computed tomography (CBCT) have been weak. Therefore, this study aimed to investigate whether CBCT is a suitable tool to detect bone erosion or invasion in patients with OSCC.

METHODS

We investigated in a prospective trial the impact of CBCT in the diagnosis of bone erosion or invasion in patients with OSCC who underwent surgery. Every participant received a CBCT, CT, and MRI scan during staging. Imaging modalities were evaluated by two specialists in oral and maxillofacial surgery (CBCT) and two specialists in radiology (CT and MRI) in a blinded way, to determine whether a bone affection was present or not. Reporting used the following 3-point system: no bony destruction ("0"), cortical bone erosion ("1"), or medullary bone invasion ("2"). Histological examination or a follow-up served to calculate the sensitivities, specificities, and accuracies of the imaging modalities.

RESULTS

Our results revealed high diagnostic sensitivities (95.6%, 84.4%, and 88.9%), specificities (87.0%, 91.7%, and 91.7%), and accuracies (89.5%, 89.5%, and 90.8%) for CBCT, CT, and MRI. A pairwise comparison found no statistical difference between CBCT, CT, and MRI.

CONCLUSION

Our data support the routine use of CBCT in the diagnosis of bone erosion and invasion in patients with OSCC as diagnostic accuracy is equal to CT and MRI, the procedure is cost-effective, and it can be performed during initial contact with the patient.

Computed tomography evaluation of alterations in the masticator space due to invasion by malignant head and neck neoplasms

Objective

To evaluate alterations in the masticator space due to the dissemination of malignant neoplasms originating from the tonsillar fossa, retromolar trigone, maxillary sinus, or nasopharynx, using computed tomography (CT), as well as to correlate the presence of trismus with the CT findings and the dimensions of the tumor.

Materials and Methods

We evaluated the medical records of 65 patients with malignant tumors in the regions described. The images were analyzed by two physician examiners, working independently, who were blinded to the clinical data. In the evaluation of the masticator space, the following parameters were considered: symmetry with the contralateral space; obliteration of the fat plane, retromolar trigone, or pharyngeal space; edema/atrophy of the medial or lateral pterygoid muscles; and destruction of the mandibular ramus.

Results

Obliteration of the fat plane was found in 69.2% of the patients. Asymmetry, edema/atrophy, and bone destruction were detected in 27.7%, 26.2%, and 20.0% of the patients, respectively. Trismus was identified in 15.4% of the patients. Of the patients with trismus, 90.0% had stage T4 tumors, compared with only 43.8% of those without trismus. Trismus was 11.6 times more common among the patients with stage T4 tumors than among those with lower-stage tumors. Neoplasms of the tonsillar fossa and retromolar trigone collectively accounted for 95.0% of the cases. The CT scans showed edema/atrophy of the pterygoid muscles in 60.0% of the patients with trismus and in 21.8% of those without. An association was observed between T4 tumor stage and edema/atrophy of the pterygoid muscles. In addition, the risk of trismus was 5.4 times higher among the patients with stage T4 tumors.

Conclusion

In our patient sample, the most common finding was obliteration of the fat plane, followed by asymmetry and edema/atrophy. Most of the patients with T4 tumors had trismus, together with edema/atrophy of the pterygoid muscles.