# Decoding Temporal Bone Carcinoma: The Role of CT and MRI in Precision Staging
## 2 Materials and Methods  
Between 2020 and 2023, a total of 2579 patients were reviewed in the Head and Neck Tumor Board at the Azienda Ospedaliera-Universitaria Policlinico Umberto I in Rome, of whom those with primary squamous cell carcinoma (SCC) of the temporal bone were selected. To be included in the study, patients had to (1) have a diagnosis of primary SCC originating from the cutaneous region of the temporal bone and (2) have undergone imaging of the temporal bone at our institution. Only patients with primary SCC of the temporal region without significant comorbidities were included in the study. A total of 15 patients who met these criteria were identified. Patient information was obtained through a retrospective review of hospital and outpatient medical records, including discharge letters and follow-up examinations, with patient consent for study purposes. The factors assessed included demographic data, presenting symptoms, physical examination findings, radiological results, surgical treatment, histopathological findings, postoperative radiotherapy, chemotherapy, targeted therapy,and/or immunotherapy. Inclusion criteria were receiving a primary SCC (squamous cell carcinoma) diagnosis of the temporal skin region; patients must have undergone temporal imaging, and no other primary tumors. Fifteen patients met these criteria and were included in the study. Patients had no comorbidities or treatment of previous neoformans. The study's CT protocol for the temporal bone included high-resolution imaging with and without contrast in the axial plane, with a slice thickness of 1.25 mm. It reconstructed images in the coronal and sagittal planes. Iomeron, a non-ionic iodinated contrast medium with lower osmolality than ionic agents, was used to reduce the risk of side effects and adverse reactions. Both soft tissue and bone windows were used for interpretative purposes. Radiologists were blinded to pathologic findings, ensuring the objectivity of their assessments. The MRI protocol for temporal bone imaging included axial T1-weighted (T1W) pre-contrast sequences (TE 10-20 ms; TR 400-600 ms), post-contrast T1W images in all three orthogonal planes, and an axial T2-weighted (T2W) sequence (TE 80-120 ms; TR 2000-300 ms). Imaging was performed on a GE Discovery MR 3 Tesla scanner with a dedicated head and neck coil. Additionally, diffusion-weighted imaging (DWI) sequences (b = 0 and 1000 s/mm\({}^{2}\)) were used to assess the tumor's characteristics, accurately evaluate its extension, and monitor treatment response. Fast spin echo (FSE) or turbo spin echo (TSE) sequences, particularly for T2W, helped reduce motion artifacts and shortened acquisition times by a factor of four. To enhance contrast and aid tumor mapping, fat-saturation (fat-sat) techniques were applied to both post-contrast T1W and T2W sequences. Gadolinium-based contrast agents (Gd) were used, specifically Gd-DOTA (Dotarem), a paramagnetic, non-specific gadolinium chelate, which accelerates the relaxation time (TR) in T1W sequences, increasing signal intensity and enhancing lesion characterization. A slice thickness of 3 mm with a gap of 0.5-1.0 mm between slices was used for all sequences. The tumors in the 15 patients were staged using the Pittsburgh staging system for SCC of the external auditory canal (EAC), based on both preoperative CT findings and histopathological results (Table 2). Potential prognostic factors were compared for 13 patients with sufficient follow-up. Patients were considered to have no evidence of disease (NED) if they had free margins and no recurrence after at least 2 years of follow-up. Statistical analysis was performed to assess the level of agreement between radiological and pathological staging. Cohen's Kappa coefficient, commonly used to measure agreement between two qualitative classifications, was employed.