Clinical features and prognostic analysis of adenoid cystic carcinoma of the external auditory canal

doi:10.3969/j.issn.1006-7795.2025.03.022

Abstract

Abstract: Objective To investigate the clinical characteristics, treatment strategies, and prognostic factors of adenoid cystic carcinoma (ACC) of the external auditory canal (EAC), and to provide evidence for optimizing surgical extent and adjuvant therapy. Methods A retrospective cohort study was conducted on 58 patients with pathologically confirmed ACC of the EAC treated in Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, between January 2001 and December 2021. All patients underwent surgical treatment, with some receiving adjuvant radiotherapy. The primary outcome was local recurrence, while secondary outcomes included overall survival (OS) and local recurrence-free survival (LRFS). Survival analysis was performed by the Kaplan-Meier method, and Cox regression models were used to identify risk factors for recurrence. Results The median follow-up time for the entire cohort was 6.27（3.25, 11.30）years. The 1-year, 3-year, and 5-year OS rates were 96.55%, 91.37%, and 89.66%. 43.10% of cases were classified as T4 stage at diagnosis, indicating advanced local progression. Local recurrence occurred in 23 patients (39.66%), and distant metastasis was observed in 28 patients (48.28%), with pulmonary metastasis accounting for 92.86% of cases. Multivariate analysis revealed that the solid histological pattern (HR=2.729, 95% CI: 1.025－7.226, P=0.044) and perineural invasion (PNI) (HR=9.891, 95% CI: 3.525－27.752, P<0.01) were independent risk factors for local recurrence. Conclusion ACC of the EAC is characterized by a high propensity for local recurrence and distant metastasis. The solid histological pattern and perineural invasion are critical prognostic determinants. Multimodal therapy (surgery combined with adjuvant radiotherapy) may improve clinical outcomes, and early diagnosis and intervention are pivotal for enhancing survival rates.

Key words: adenoid cystic carcinoma, perineural invasion, solid histological pattern, local recurrence, comprehensive treatment

CLC Number:

R762

Wu Jun, Zhao Xi, Ma Tingyao, Yang Guoliang, Zhang Shujing, Zhao Yue, Liu Yixuan, Chen Xiaohong. Clinical features and prognostic analysis of adenoid cystic carcinoma of the external auditory canal[J]. Journal of Capital Medical University, 2025, 46(3): 559-566.

References

［1］Gidley P W, Thompson C R, Roberts D B, et al. The oncology of otology［J］. Laryngoscope, 2012, 122: 393－400.
［2］Zupancic M, Näsman A, Friesland S, et al. Adenoid cystic carcinoma, clinical presentation, current treatment and approaches towards novel therapies［J］. Anticancer Res, 2024, 44(4): 1325－1334.
［3］Stawarz K, Durzynska M, Gałazka A, et al. Current landscape and future directions of therapeutic approaches for adenoid cystic carcinoma of the salivary glands (Review)［J］. Oncol Lett, 2025, 29(3): 153.
［4］Zhang T, Dai C, Wang Z. The misdiagnosis of external auditory canal carcinoma［J］. Eur Arch Otorhinolaryngol, 2013, 270(5): 1607－1613.
［5］Bonaparte J P, Trites J, Hart R, et al. Survival when treating adenoid cystic carcinoma of the external auditory canal: quantitative assessment of case reports［J］. J Otolaryngol Head Neck Surg, 2009, 38(4): 468－476.
［6］Liu H, Zhang Y, Zhang T, et al. Correlation between the pathology and clinical presentations in patients with adenoid cystic carcinoma of the external auditory canal［J］. Head Neck, 2017, 39(12): 2444－2449.
［7］van Weert S, van der Waal I, Witte B I, et al. Histopathological grading of adenoid cystic carcinoma of the head and neck: analysis of currently used grading systems and proposal for a simplified grading scheme［J］. Oral Oncol, 2015, 51(1): 71－76.
［8］Li X, Yang X, Lin S, et al. Perineural invasion in cervical cancer［J］. Cancer Lett, 2025, 616: 217561.
［9］Ju J, Li Y, Chai J, et al. The role of perineural invasion on head and neck adenoid cystic carcinoma prognosis: a systematic review and meta-analysis［J］. Oral Surg Oral Med Oral Pathol Oral Radiol, 2016, 122(6): 691－701.
［10］Arriaga M, Curtin H, Takahashi H, et al. Staging proposal for external auditory meatus carcinoma based on preoperative clinical examination and computed tomography findings［J］. Ann Otol Rhinol Laryngol, 1990, 99(9 Pt 1): 714－721.
［11］Moody S A, Hirsch B E, Myers E N. Squamous cell carcinoma of the external auditory canal: an evaluation of a staging system［J］. Am J Otol, 2000, 21(4): 582－588.
［12］Wang Y, Xu L, Guan B, et al. The study on prognosis in patients with adenoid cystic carcinoma of the external auditory canal［J］. J Int Adv Otol, 2023, 19(2): 149－154.
［13］赵海, 杨博文, 王效军, 等. 外耳道腺样囊性癌误诊为外耳道炎2例［J］. 中国耳鼻咽喉头颈外科, 2018, 25(11): 621－622.
［14］徐军, 孙峰, 王亚,等. 急诊气道管理共识［J］. 中国急救医学, 2016, 36(06): 481－485.
［15］Chen S L, Huang S F, Ho V W, et al. Clinical characteristics and treatment outcome of adenoid cystic carcinoma in the external auditory canal［J］. Biomed J, 2020, 43(2): 189－194.
［16］Jiang X, Jia L, Zhang X, et al. Clinical experience of 23 cases of adenoid cystic carcinoma of the external auditory canal［J］. Oncol Lett, 2020, 20(5): 144.
［17］Feng Y, Li F, Wang J, et al. Risk factors for locoregional recurrence and distant metastasis in 143 patients with adenoid cystic carcinoma of the external auditory canal［J］. Clin Oncol (R Coll Radiol), 2024, 36(1): e40－e50.
［18］刘强, 薛玉斌, 张文阳, 等. 颞骨次全切除术治疗外耳道腺样囊性癌的疗效分析［J］. 中国耳鼻咽喉颅底外科杂志, 2023, 29(03): 45－48.
［19］戴春富, 李轩毅. 外耳道腺样囊性癌临床诊断和治疗的现状和探讨［J］. 临床耳鼻咽喉头颈外科杂志, 2018, 32(20): 1527－1530.
［20］Leonetti J P, Smith P G, Kletzker G R, et al. Invasion patterns of advanced temporal bone malignancies［J］. Am J Otol, 1996, 17(3): 438－442.
［21］Liu S C, Kang B H, Nieh S, et al. Adenoid cystic carcinoma of the external auditory canal［J］. J Chin Med Assoc, 2012, 75(6): 296－300.
［22］Dong L, Wang Y X, Li S L, et al. TGF-beta1 promotes migration and invasion of salivary adenoid cystic carcinoma［J］. J Dent Res, 2011, 90(6): 804－809.
［23］Perzin K H, Gullane P, Conley J. Adenoid cystic carcinoma involving the external auditory canal. A clinicopathologic study of 16 cases［J］. Cancer, 1982, 50(12): 2873－2883.
［24］Perzin K H, Gullane P, Clairmont A C. Adenoid cystic carcinomas arising in salivary glands: a correlation of histologic features and clinical course［J］. Cancer, 1978, 42: 265－282.
［25］Szanto P A, Luna M A, Tortoledo M E, et al. Histologic grading of adenoid cystic carcinoma of the salivary glands［J］. Cancer, 1984, 54(6): 1062－1069.
［26］Pemberton L S, Swindell R, Sykes A J. Primary radical radiotherapy for squamous cell carcinoma of the middle ear and external auditory canal—an historical series［J］. Clin Oncol (R Coll Radiol), 2006, 18(5): 390－394.
［27］Hashi N, Shirato H, Omatsu T, et al. The role of radiotherapy in treating squamous cell carcinoma of the external auditory canal, especially in early stages of disease［J］. Radiother Oncol, 2000, 56(2): 221－225.

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