Clinical management for T1 and T2 external auditory canal cancer

Abstract

Objective: The purpose of this study was to clarify the impact of superficial parotidectomy and postoperative radiotherapy (PORT) for the surgical treatment of early stage squamous cell carcinoma (SCC) in external auditory canal (EAC). Materials and Methods: Thirty-seven patients with T1 (n=14) or T2 (n=19) SCC in EAC treated between 2000 and 2016 at Kobe University Hospital were enrolled in this study. Thirty-three patients were operated with sleeve resection or lateral temporal bone resection. Results: The 5-year overall survival and disease-specific survival rates were 95% and 100%, respectively. Surgical margin was positive in 4 patients, who were treated by PORT and have been alive without disease. Prophylactic superficial parotidectomy was simultaneously performed at the time of initial surgery in 15 patients, in whom no lymph node (LN) metastasis was observed. Among the other 22 patients, regional recurrence in parotid LN was observed in one patient, who was successfully salvaged by total parotidectomy. Potential parotid lymph node metastasis rates of T1 and T2 SCC in EAC was 0% (0/14) and 5%(1/19) respectively. Conclusions: Complete resection without positive surgical margins is essential for the treatment of the patients with T1 and T2 ear cancers. Prophylactic superficial parotidectomy or neck dissection is not mandatory for T1 and T2 diseases, as long as precisely extent of disease is assessed preoperatively. PORT should be performed for the patients with positive surgical margins.

Treatment Outcome of External Auditory Canal Carcinoma: The Utility of Lateral Temporal Bone Resection

“…Although there have been no large cohort studies due to its rarity, complete surgical resection is considered to be an optimal treatment (5). For this purpose, sleeve resection or lateral temporal bone resection (LTBR) is suitable for T1/T2 tumors that are localized to the EAC and EAC with bone erosion or with <0.5 mm soft tissue involvement, for which favorable outcomes have been reported (6,7). On the other hand, subtotal temporal bone resection (STBR) has been proposed as a standard surgery for advanced carcinoma, which is a more invasive and challenging approach than LTBR because of its anatomical complexity (5,8).…”

Stereotactic Radiotherapy for Localized External Auditory Canal Carcinomas: Report of Four Cases

“…Of various head and neck cancers, it is reported that the early-stage nasal and paranasal carcinomas [3][4][5] and early-stage external auditory canal carcinomas (EACCa) [1,2] rarely develop regional LN metastasis or cervical lymph node metastases [6]. Such patients might be good candidates for stereotactic radiosurgery (SRS)/SRT as an upfront therapy instead of surgical extirpation as the initial therapy [6].…”

“…Recently, Shinomiya et al [ 1 ] reported the good results of surgical treatment of early-stage EACC in 33 cases (T1, 14; T2, 19). All were SCC and were operated on with sleeve resection or lateral temporal bone resection.…”

“…External auditory canal carcinoma (EACC) is sometimes diagnosed at an early stage because it arises superficially in the ear canal and may cause ear obstruction symptoms early. In addition, in the early stage of EACCs, involvement of lymph nodes or distant metastases are reported less frequently [ 1 , 2 ]. Therefore, stereotactic radiotherapy (SRT) concentrating high-dose radiation on the primary tumor may be an effective option.…”

Stereotactic Radiosurgery and Stereotactic Radiotherapy for Malignant Skull Base Tumors

“…Of various head and neck cancers, it is reported that only 10-15% of early-stage nasal and paranasal carcinomas (NpNCa) have cervical lymph node (LN) involvement [14][15][16]. Also, patients with early-stage external auditory canal carcinomas (EACCa) rarely develop regional LN metastasis [17,18]. Such patients might be good candidates for SRS/SRT as an upfront therapy, instead of surgical extirpation, as the initial therapy.…”