Clinical Outcome and Prognostic Factors in Adenoid Cystic Carcinoma of the External Auditory Canal: Proposal for a Refined T-stage Classification System

Overview

Journal Eur Arch Otorhinolaryngol

Specialty Otorhinolaryngology

Date 2023 Feb 13

PMID 36781438

Authors

Jung-Yup Lee

Yang-Sun Cho

Affiliations

Soon will be listed here.

Abstract

Purpose: Although adenoid cystic carcinoma (ACC) of the external auditory canal (EAC) has a different pathophysiology from squamous cell carcinoma, the same staging system is used. The aim of this study was to propose a refined staging system, which is more suitable for ACC of the EAC.

Methods: A total of 25 patients who were diagnosed with ACC of the EAC were reviewed. The modified Pittsburgh staging system (mPSS) that is universally used for temporal bone malignancy was refined for ACC (rPSS). The limited (< 0.5 cm) lateral soft tissue involvement was classified as T1 and extensive (≥ 0.5 cm) lateral soft tissue involvement as T2. The disease-free survival rate (DFSR) was assessed in the patients who underwent surgical treatment according to two staging systems; mPSS and rPSS.

Results: When staging using mPSS, most patients (96.0%, n = 24) were classified as T4. However, when rPSS was used, T1, T2, T3, and T4 stage occupied 36.0% (n = 9), 40.0% (n = 10), 12.0% (n = 3), 12.0% (n = 3), respectively. There was no difference in DFSR according to the T stage using mPSS (p = 0.466). However, when rPSS was used, the DFSR showed significant correlation with the T stage (p = 0.032).

Conclusions: Clinical T stage of mPSS was not sufficient to predict survival rate in ACC of the EAC, and we propose that the information on the lateral soft tissue involvement needs to be added to the existing staging system.

References

Testa J, Fukuda Y, Kowalski L . Prognostic factors in carcinoma of the external auditory canal. Arch Otolaryngol Head Neck Surg. 1997; 123(7):720-4. DOI: 10.1001/archotol.1997.01900070064010. View

Dong F, Gidley P, Ho T, Luna M, Ginsberg L, Sturgis E . Adenoid cystic carcinoma of the external auditory canal. Laryngoscope. 2008; 118(9):1591-6. DOI: 10.1097/MLG.0b013e31817c42a8. View

SPIRO R, Huvos A . Stage means more than grade in adenoid cystic carcinoma. Am J Surg. 1992; 164(6):623-8. DOI: 10.1016/s0002-9610(05)80721-4. View

Jiang X, Jia L, Zhang X, Zhong C, Tang F, Chen X . Clinical experience of 23 cases of adenoid cystic carcinoma of the external auditory canal. Oncol Lett. 2020; 20(5):144. PMC: 7471729. DOI: 10.3892/ol.2020.12005. View

Morita S, Mizumachi T, Nakamaru Y, Sakashita T, Kano S, Hoshino K . Comparison of the University of Pittsburgh staging system and the eighth edition of the American Joint Committee on Cancer TNM classification for the prognostic evaluation of external auditory canal cancer. Int J Clin Oncol. 2018; 23(6):1029-1037. DOI: 10.1007/s10147-018-1314-3. View

Moody S, Hirsch B, Myers E . Squamous cell carcinoma of the external auditory canal: an evaluation of a staging system. Am J Otol. 2000; 21(4):582-8. View

Thompson L, Nelson B, Barnes E . Ceruminous adenomas: a clinicopathologic study of 41 cases with a review of the literature. Am J Surg Pathol. 2004; 28(3):308-18. DOI: 10.1097/00000478-200403000-00003. View

Nabuurs C, Kievit W, Labbe N, Leemans C, Smit C, van den Brekel M . Evaluation of the modified Pittsburgh classification for predicting the disease-free survival outcome of squamous cell carcinoma of the external auditory canal. Head Neck. 2020; 42(12):3609-3622. PMC: 7754129. DOI: 10.1002/hed.26424. View

Szanto P, Luna M, Tortoledo M, White R . Histologic grading of adenoid cystic carcinoma of the salivary glands. Cancer. 1984; 54(6):1062-9. DOI: 10.1002/1097-0142(19840915)54:6<1062::aid-cncr2820540622>3.0.co;2-e. View

10.

SPIRO R, Huvos A, Strong E . Adenoid cystic carcinoma of salivary origin. A clinicopathologic study of 242 cases. Am J Surg. 1974; 128(4):512-20. DOI: 10.1016/0002-9610(74)90265-7. View

11.

Chen S, Huang S, Ho V, Chuang W, Chan K . Clinical characteristics and treatment outcome of adenoid cystic carcinoma in the external auditory canal. Biomed J. 2020; 43(2):189-194. PMC: 7283548. DOI: 10.1016/j.bj.2019.07.005. View

12.

Zhang T, Dai C, Wang Z . The misdiagnosis of external auditory canal carcinoma. Eur Arch Otorhinolaryngol. 2012; 270(5):1607-13. DOI: 10.1007/s00405-012-2159-4. View

13.

Gu F, Chi F, Dai C, Chen B, Li H . Surgical outcomes of 43 cases with adenoid cystic carcinoma of the external auditory canal. Am J Otolaryngol. 2013; 34(5):394-8. DOI: 10.1016/j.amjoto.2013.01.018. View

14.

Liu H, Zhang Y, Zhang T, Li F, Dai C . Correlation between the pathology and clinical presentations in patients with adenoid cystic carcinoma of the external auditory canal. Head Neck. 2017; 39(12):2444-2449. DOI: 10.1002/hed.24915. View

15.

Ishida E, Ogawa T, Rokugo M, Ishikawa T, Wakamori S, Ohkoshi A . Management of adenoid cystic carcinoma of the head and neck: a single-institute study with over 25-year follow-up. Head Face Med. 2020; 16(1):14. PMC: 7330995. DOI: 10.1186/s13005-020-00226-2. View

16.

Min R, Siyi L, Wenjun Y, Ow A, Lizheng W, Minjun D . Salivary gland adenoid cystic carcinoma with cervical lymph node metastasis: a preliminary study of 62 cases. Int J Oral Maxillofac Surg. 2012; 41(8):952-7. DOI: 10.1016/j.ijom.2012.04.023. View

17.

Green R, Megwalu U . Adenoid cystic carcinoma of the external ear: a population based study. Am J Otolaryngol. 2016; 37(4):346-50. DOI: 10.1016/j.amjoto.2016.02.001. View

18.

Gidley P . Managing malignancies of the external auditory canal. Expert Rev Anticancer Ther. 2009; 9(9):1277-82. DOI: 10.1586/era.09.93. View

19.

Choi S, Yang A, Yoon S, Kim H, Hong M, Kim S . Role of postoperative radiotherapy in resected adenoid cystic carcinoma of the head and neck. Radiat Oncol. 2022; 17(1):197. PMC: 9716721. DOI: 10.1186/s13014-022-02165-5. View

20.

Perzin K, Gullane P, Clairmont A . Adenoid cystic carcinomas arising in salivary glands: a correlation of histologic features and clinical course. Cancer. 1978; 42(1):265-82. DOI: 10.1002/1097-0142(197807)42:1<265::aid-cncr2820420141>3.0.co;2-z. View