Squamous cell carcinoma of the external auditory canal: A case report and review of the literature

Long-term analysis of prognostic risk factors impacting surgical outcomes in patients with external auditory canal carcinoma

BACKGROUND

Malignant neoplasms of the external auditory canal (EAC) are rare. No consensus on management has emerged.

OBJECTIVE

To determine possible risk factors influencing tumorgenesis and prognosis of EAC carcinoma.

MATERIALS AND METHODS

108 patients (87 men/21 women) with an average age of 74 ± 13.8 years were recruited from 2005 to 2019 at Department of Otorhinolaryngology, Head and Neck Surgery Heidelberg. The follow-up interval was 43.62 ± 55.39 months. Partial and (sub)total ablative otis, supplementary surgery (petrosectomy, parotidectomy, neck dissection, mastoidectomy) and adjuvant radio(chemo)therapy belonged to treatment options. TNM status was determined at time of diagnosis using the AJCC staging system.

RESULTS

63.9% of patients underwent a total ablative otis. Tumor recurrence was seen in 24.1%. The 1-year survival rate was 87%, the 5-year survival rate was 52%, the mean overall survival (OS) was 3.82 ± 4.6 years. Male EAC carcinoma patients had a better OS (p < 0.001), PFS (p < 0.001) and DSS (p = 0.02) than females. T1 patients had a better OS (p = 0.01), PFS (p = 0.01) and DSS (p < 0.001) than T4 patients. Lymph node but not distant metastasis, tumor grading, perineural, venous and lymphatic invasion, histology, age and tumor localization influenced the OS in EAC carcinoma patients (p = 0.04). The more radical the ablative otis, the worse the OS (p = 0.002), PFS (p = 0.02) and DSS (p < 0.001). Radio(chemo)therapy did not improve the OS.

CONCLUSIONS

EAC carcinoma are difficult to treat and benefit from early diagnosis so that a radical combined treatment approach does not need to be used.

Evidence Based Tailored Parotidectomy in Treating External Auditory Canal Carcinoma

Carcinoma of the external auditory canal (EAC) is a rare tumor and little information is available regarding parotid gland in surgically treating EAC carcinomas. This study aimed to investigate the mode of parotid involvement in EAC carcinoma through staging and histopathological analysis, and to establish surgical guidelines for the parotid gland management when there is no clinical evidence of parotid involvement. Sixty-five patients with EAC carcinoma who underwent temporal bone resection and any type of parotidectomy simultaneously were retrospectively reviewed. The rate of direct parotid invasion and parotid nodal involvement was analyzed according to the stage and histopathological findings. Among the 65 patients, 39 were confirmed to have squamous cell carcinoma (SCC) and 26 were confirmed to have adenoid cystic carcinoma (ACC). Direct parotid invasion occurred in 7 of 39 patients with SCC, only in the advanced stages, and in 15 of 26 patients with ACC, regardless of stage. Metastasis to the parotid node was noted in 6 patients with advanced-stage SCC, whereas no patient with ACC showed parotid nodal metastasis. For adequate tumor control with low risk of surgical complications, evidence based tailored parotidectomy should be applied. With no evidence of parotid involvement, an elective parotidectomy can be excluded in early SCC, whereas a total parotidectomy is recommended for advanced SCC. In ACC, basal resection of the parotid gland rather than a superficial or total parotidectomy should be performed at all disease stages.

The contribution of CT and MRI in staging, treatment planning and prognosis prediction of malignant tumors of external auditory canal

Carcinomas of external auditory canal (EAC) are rare. Radiological imaging particular in computed tomography (CT) and magnetic resonance imaging (MRI) plays an important role in the staging, treatment planning and follow up of the patients with malignant EAC tumor. This article aims to review the role of CT and MRI in the describing different tumor growth pattern, tumor staging, treatment planning, follow up and predicting the prognosis of malignant tumors of EAC.

Radiological Findings of Malignant Tumors of External Auditory Canal: A Cross-Sectional Study Between Squamous Cell Carcinoma and Adenocarcinoma

The primary malignant tumors of external auditory canal (EAC) are rare. The purpose of this study is to compare the imaging features of growth and recurrence pattern between 2 most common carcinomas namely squamous cell carcinoma (SCC) and adenocarcinoma of the EAC.This is a retrospective study involving 41 patients with primary EAC carcinomas of which 22 are SCC and 19 are adenocarcinoma. They were all scanned with high resolution computer tomography (HRCT) and magnetic resonance imaging. Follow-up clinical and imaging studies have also been collected and compared with a median follow-up time of 43 months (range 5-192 months). Necrosis was presented as hypodensity on computed tomography images, hyper-intense on T2WI and heterogeneous enhancement.Eighteen patients were diagnosed to be in T1 and T2 stage, it was found that SCC involved both the cartilaginous part and the bony part of the EAC (11/12), whereas adenocarcinoma involved only the cartilaginous part (6/6) (P < 0.01). Twenty-three patients were diagnosed to be in T3 and T4 stage showed bony involvement and adjacent tissue involvement for both SCC and adenocarcinoma. Parapharyngeal space involvement is much more common in recurrent SCC (P = 0.02). Lymph node metastasis was seen in 6 out of 22 patients with SCC, while 5 out of 19 patients of adenocarcinoma had lung metastasis, even at early stage (1/6; 1/5). Necrosis is more likely to occur in the patients with SCC (9/10) than that of adenocarcinoma (3/13) (P = 0.02).SCC and adenocarcinoma is seen to have different growth pattern at early stage but share similar patterns in the advanced stage. Lymph node metastasis is commonly seen in patients with SCC while adenocarcinoma shows lung metastasis even at early stage.

Squamous cell carcinoma of the middle ear: report of three cases

Squamous cell carcinoma of the middle ear (SCCME) accounts for 1.5% of malignant tumors in the ear. Because of the low incidence and infrequent reports of SCCME, the extent of concordance between CT and MRI results, surgical findings, and pathology reports are not well-characterized. In the present study, we reported CT and MRI images in three SCCME cases, and assessed the relationship between these results and those of surgery and the pathological report. Middle ear carcinoma is frequently misdiagnosed before surgery. In three cases of middle ear carcinoma, CT revealed the following: 1) soft tissue density lesions centered around the middle tympanum, exhibiting increased density, with external auditory canal involvement; 2) damage and absorption in the mastoid area, ossicles, and facial nerve canal, characterized by an irregular, worm-eaten appearance, without sclerotic margins; and 3) lesion infiltration of the surrounding bony substance of the middle ear, temporal squama, temporomandibular joint, anterior wall of the sigmoid sinus, and horizontal segment of the canalis caroticus (in one case lesion invasion into the intracranial cavity occurred through sigmoid sinus walls; no signs of intracranial invasion were seen in the other two cases). Enhanced lesion imaging revealed partial heterogeneous enhancement. In one patient MRI revealed a defined mass in the mastoid area of the middle ear. Signals in the lesion were partially heterogeneous and similar to brain tissue in T1- and T2-weighted images. The lesion was significantly enhanced following application of a contrast agent, while the adjacent meninges also exhibited linear enhancement. No abnormal signals were detected in the brain parenchyma. The destruction of adjacent bone plates was poorly defined. The CT and MRI results were consistent with the invasive features of middle ear cancer documented in the post-surgery pathology report.