Value of ^(99m)Tc-MDP SPECT/CT fusion imaging and CT in evaluating the extent of mandibular invasion by malignant tumor of oral cavity

Objective： The aim of our study was to compare the value of computed tomography （CT） and 99mTc-methylene- diphosphonate （MDP） SPECT （single photon emission computed tomography）/CT fusion imaging in determining the extent of mandibular invasion by malignant tumor of the oral cavity. Methods： This study had local ethical committee approval, and all patients gave written informed consent. Fifty-three patients were revealed mandibular invasion by malignant tumor of the oral cavity underwent CT and SPECT/CT. The patients were divided into two groups： group A （invasion-periphery-type） and group B （invasion-center- type）. Two radiologists assessed the CT images and two nuclear medicine physicians separately assessed the $PECT/CT images in consensus and without knowledge of the results of other imaging tests. The extent of bone involvement suggested with an imaging modality was compared with pathological findings in the surgical specimen. Results： With pathological findings as the standard of reference, Group A： The extent of mandibular invasion by malignant tumor under- went SPECT/CT was 1.02 _＋ 0.20 cm larger than that underwent pathological findings. And the extent of mandibular invasion underwent CT was 1.42 ＋ 0.35 cm smaller than that underwent pathological examination. There were significant difference among the three methods （P 〈 0.01）. Group B： The extent of mandibular invasion by malignant tumor underwent SPECT/CT was 1.3 ＋ 0.39 cm larger than that underwent pathological examination. The extent of mandibular invasion underwent CT was 2.55 ＋ 1.44 cm smaller than that underwent pathological findings. There were significant difference among the three methods （P 〈 0.01）. The extent of mandibular invasion underwent SPECT/CT was the extent which surgeon must excise to get clear margins. Conclusion： SPECT/CT fusion imaging has significant clinical value in determining the extent of mandibular inva- sion by malignant tumor of oral cavity.

Diagnostic Role of Computerised Tomography in Mandibular Invasion among Patients with Oral Squamous Cell Carcinoma

Background: Oral cavity malignancy can result from surface epithelium, salivary glands, or submucosal soft tissue. Common symptoms may include non-healing ulcers, slurred speech, dysphagia, neck mass and pain which may indicate cortical invasion. Morbidity and quality of life have been seen to rise with mandibular excision in oral cavity squamous cell carcinoma. Therefore, in order to design the surgery appropriately, it is vital to be aware of the mandibular invasion prior to the procedure. Various researches have been focused on the accuracy of clinical examination and imaging technique in predicting tumour invasion of the mandible in oral malignancy. The goal of this study was to find a correlation between histological assessment, clinical examination, and computed tomography results in patients with mandibular involvement and oral cavity squamous cell carcinoma. Objectives: To determine the sensitivity, specificity, NPV and PPV of CECT and clinical diagnosis in patients with oral squamous cell carcinoma with mandibular invasion. Methods: A cross-sectional observational study was set out to review preoperative clinical and radiological assessment;and post operative histopathological finding of mandibular resection specimen in clinically evaluated and diagnosed cases of oral cavity squamous cell carcinoma (SCC) with mandibular invasion. Results: 43 individuals of oral cavity SCC with mandibular involvement were examined. 12 out of 28 mandibular resections had bone invasion, with numerous tumour entry sites being the most frequent mechanism of invasion, according to post-operative HPE. The positive predictive value (PPV) of contrast enhanced computerised tomography (CECT) scans was 42.8%, as 28 individuals had invasions revealed;sensitivity is almost 100%;specificity is 48.3. Conclusion: Prioritizing the identification of mandibular invasion is essential to enhance the prognosis of patients with oral SCC. There is an urgent necessity to review the usefulness of radiology in the treatment of mandibulectomy. Combination of clinical and radiological examination increases sensitivity and specificity.