[Comparative study of benign and malignant parotid gland tumors by infrared thermal imaging]

Objective: To analyze the temperature difference of benign and malignant parotid gland tumors in preoperative infrared thermography (IRT), and to provide the basis for predicting tumor properties. Methods: The clinical data of 98 patients with parotid gland tumor admitted to the Department of Oral and maxillofacial Surgery of the First Affiliated Hospital of Bengbu Medical College, from May 2021 to April 2023 were retrospectively analyzed. There were 61 males and 37 females, aged (51.1±16.0) years (10-86 years). In addition to routine examination, the temperature difference between the lesion site of parotid gland and the contralateral mirror area was measured by infrared thermal imager in all patients one day before surgery. The maximum diameter (dmax) and location of the tumor (deep or superficial lobe) were recorded according to preoperative clinical examination and imaging examinations such as CT and ultrasound. The patients were divided into three groups by tumor size: dmax≤2 cm, 2 cm4 cm. The patients were also divided into different groups: deep lobe group and superficial lobe group (according to the tumor location), benign group and malignant group (according to postoperative pathological results). The relationship between temperature difference, pathology, size and location was analyzed. Results: There were 79 cases in the benign group and 19 cases in the malignant group. The temperature difference of the healthy and affected side in the malignant group [(1.73±0.21) ℃] was significantly higher than that in the benign group [(0.73±0.32) ℃] (t=16.70, P<0.001). There was no significant difference in temperature difference between the healthy and affected sides of tumors with different diameters (P>0.05). The temperature difference of healthy and affected side of tumor in superficial lobe [(0.97±0.50) ℃] was significantly higher than that in deep lobe [(0.67±0.44) ℃] (t=2.24, P=0.028). Conclusions: The difference of temperature difference between benign and malignant parotid gland tumors detected by IRT is statistically significant, which can be used to predict tumor properties, and has certain clinical application value.