A 70-year-old female patient complaining of persistent pain in the left temporal region was referred to our university hospital by her physician. Audiometry and examination of the tympanic membrane yielded no unremarkable findings. Further diagnostic evaluation by computed tomography of the temporal bone revealed an infiltrative opacity and irregularity in the temporal bone, and on magnetic resonance imaging, both T1- and T2-weighted images revealed low signal intensity signals in the same area. Based on the presence of an infiltrative opacity in the left middle ear, elevated conductive thresholds in the temporal bone, and left facial nerve paresis, we scheduled a biopsy of the temporal bone lesion. A preoperative workup uncovered evidence of a primary lung neoplasm located in the middle lobe of the left lung. Histopathological examination confirmed the primary lung cancer, and consistent histological features in the temporal bone lesions. While the temporal bone is a relatively uncommon site of metastasis from malignant tumors, the most common primary sites are the lung, breast, and prostate. It is therefore recommended to conduct a systematic investigation of temporal bone lesions, including a search for primary tumors, given the possibility of malignant tumor metastasis in patients presenting with temporal bone lesions.
