Surgery With or Without Postoperative Radiation Therapy for Early-stage External Auditory Canal Squamous Cell Carcinoma: A Meta-analysis

Treatment outcomes of 73 cases of external auditory canal squamous cell carcinoma: A single-center six-year analysis in Japan

OBJECTIVES

External auditory canal cancer (EAC) is a rare type among head and neck cancers, predominantly composed of squamous cell carcinoma (SCC) pathologically. Various comprehensive treatments including surgery, radiation therapy, and chemotherapy are conducted in many facilities for squamous cell carcinoma of the external auditory canal. However, due to its rarity, there is no established standard treatment. This study aimed to report the treatment outcomes at our single facility and prognostic factors post-surgery for EAC-SCC.

METHODS

We conducted a retrospective analysis of 73 cases of EAC-SCC, which underwent initial treatment at our facility from July 2015 to November 2022. We utilized the modified Pittsburgh classification for TNM and staging.

RESULTS

There were 37 male and 36 female cases, with a median age of 65 (ranging from 40 to 93). T1: 32 cases, T2: 5 cases, T3: 14 cases, T4: 10 cases. Stage Ⅰ: 28 cases, stage Ⅱ: 5 cases, stage Ⅲ: 12 cases, stage Ⅳ: 16 cases. The median follow-up period was 23.8 months (ranging from 2.8 to 93.6 months). There were 61 cases in the surgery group and 12 cases in the chemoradiotherapy (CRT) group. In survival analysis, the overall 3-year recurrence-free survival (RFS) rate was 81.9 %, and the 3-year disease-specific survival (DSS) rate was 89.1 %. For stage III/IV advanced cancers, the 3-year RFS rate was 78.3 % and DSS rate was 79.1 % in the surgery group, and in the CRT group, they were 66.7 % and 91.7 %, respectively. For T4 cases, the 3-year RFS rate was 58.3 % and DSS rate was 61.0 % in the surgery group, and in the primary CRT group, they were 75.0 % and 87.5 %, respectively. While there were no significant differences in treatment outcomes between the surgery and CRT groups overall, there was a trend suggesting better outcomes in the CRT group for T4 cases. In advanced cases (Stage III/IV, T3/4), younger females tended to be treated with CRT. Positive resection margins (HR: 11.97, 95 % CI: 1.80-79.70, p = 0.010) revealed to be a significant prognostic factor based on RFS.

CONCLUSION

We reported the treatment outcomes at a single facility and post-surgery prognostic factors. The treatment outcomes at our facility are comparable to other institutions, and in advanced cancers, the CRT group showed a tendency for better treatment outcomes. Post-surgery prognostic factor was positive resection margins.

The international expert consensus on management of external auditory canal carcinoma

PURPOSE

The objective of this consensus is to provide otolaryngologists with appropriate strategies in the management of external auditory canal (EAC) carcinoma.

METHODS

In the absence of randomized controlled trials, the consensus is based on expert opinions utilizing the Rand/UCLA appropriateness method [Fitch and Aguilar in The RAND/UCLA appropriateness method user's manual, RAND Corporation, Santa Monica, CA, 2001], drawing from existing literature and clinical experience.

RESULTS

The management recommendations are structured around 12 key areas, including: definition and pathology, pathogenesis, clinical manifestations, work-up, tumor staging system, surgical management of primary tumor, surgical management of the parotid gland and the temporomandibular joint, lymph node metastasis, radiotherapy, chemotherapy, reconstruction, and follow-up.

CONCLUSION

Management strategies for EAC carcinoma rely on tumor extension and histopathological features. Surgical removal with free surgical margins or combination with radiotherapy, chemotherapy are most often the best options. Given the rarity of the disease, prospective, randomized, multi-institutional clinical trials should be designed to enable reliable comparisons of the outcomes of EAC carcinoma treatments, thereby providing evidence-based clinical data to establish widely accepted guidelines. It emphasizes the need for a multidisciplinary team to be involved in the management of EAC carcinoma, and regular follow-up should be implemented postoperatively.

Postoperative Radiotherapy for pT1- and pT2-Classified Squamous Cell Carcinoma of the External Auditory Canal

BACKGROUND

There is no consensus regarding the indication for postoperative radiotherapy (PORT) for T1- and T2-classified squamous cell carcinoma (SCC) of the external auditory canal (EAC) even with negative surgical margins. This study aimed to evaluate whether PORT provides additional benefits for these cases.

METHODS

We collected retrospective data from fourteen international hospitals, including resected pT1- and pT2-classified EAC SCC with negative surgical margins.

RESULTS

A total of 112 early-stage radically resected EAC SCC were included, with 48 patients receiving PORT. The 5-year DFS of T1- and T2-classified EAC SCC treated with PORT was not statistically significantly different (92.9% and 76.9%, respectively) compared to the group treated without PORT (100% and 90.9%, respectively; p-values of 0.999 and 0.526, respectively). EAC SCC treated with PORT more frequently exhibited perineural and angioinvasive growth. Eighteen patients experienced side effects related to radiotherapy, of which one patient developed osteoradionecrosis.

CONCLUSIONS

Our study suggests that PORT for early-stage radically resected EAC SCC should only be considered in selected cases with perineural, infiltrative growth or angioinvasive growth, and with a close margin. This approach helps mitigate the negative impact on quality of life and the risk of side effects associated with radiotherapy.

Survival Outcomes of Temporal Bone Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

OBJECTIVE

Temporal bone squamous cell carcinoma (TBSCC) is a rare malignancy with poor prognosis, and optimal treatment for advanced cases is uncertain. Our systematic literature review aimed to assess 5-year survival outcomes for advanced TBSCC across different treatment modalities.

DATA SOURCES

EMBASE, Medline, PubMed, and Web of Science.

REVIEW METHODS

A systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for articles published between January 1989 and June 2023.

RESULTS

The review yielded 1229 citations of which 31 provided 5-year survival data for TBSCC. The final analysis included 1289 patients. T classification data was available for 1269 patients and overall stage for 1033 patients. Data for 5-year overall survival (OS) was 59.6%. Five-year OS was 81.9% for T1/2 and 47.5% for T3/4 (P < .0001). OS for T1/T2 cancers did not significantly differ between surgery and radiation (100% vs 81.3%, P  = .103). For advanced-stage disease (T3/T4), there was no statistical difference in OS when comparing surgery with postoperative chemoradiotherapy (CRT) (OS 50.0%) versus surgery with postoperative radiotherapy (XRT) (OS 53.3%) versus definitive CRT (OS 58.1%, P  = .767-1.000). There was not enough data to assess the role of neoadjuvant CRT.

CONCLUSION

Most patients will present with advanced-stage disease, and nodal metastasis is seen in nearly 22% of patients. This study confirms the prognostic correlation of the current T classification system. Our results suggest that OS did not differ significantly between surgery and XRT for early stage disease, and combined treatment modalities yield similar 5-year OS for advanced cancers.

Survival Outcomes in Squamous Cell Carcinoma of the External Auditory Canal: A Systematic Review and Meta-Analysis

Squamous cell carcinomas (SCC) of the external auditory canal (EAC) are rare tumors representing a surgical challenge. Current knowledge is based largely on case series; thus, the level of evidence is weak. This study sought to systematically review the available SCC of the EAC literature and to identify risk factors for overall survival (OS) and disease-specific survival (DSS). A systematic review and meta-analysis of papers searched up to December 2022 through PubMed, Scopus, Web of Science, and Cochrane Library databases was conducted. Quality assessment of the eligible studies was done according to the Newcastle-Ottawa Scale. Pooled univariate and multivariable analyses and meta-analysis using a random-effects or fixed-effects Mantel-Haenszel model were performed. Fifteen articles (282 patients) met the inclusion criteria and were included in the quantitative analysis. The pooled multivariable analysis revealed cT3 and cT4 as independent prognostic factors for OS (p = 0.005, and p < 0.001, respectively) and DSS (p = 0.002, and p < 0.001, respectively). Local recurrence rate was 32.3%. The meta-analysis estimated significantly higher odds ratios for advanced T categories, than cT1-T2 tumors for OS and DSS (OR = 3.55; 95% CI, 1.93–6.52, and OR = 3.73; 95% CI, 2.00–6.97, respectively). In conclusion, locally advanced tumors were associated with poor prognosis. Poor outcomes mostly occurred due to local recurrence.

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.

Temporal Bone Resection for Squamous Cell Carcinoma of the Lateral Skull Base: Systematic Review and Meta-analysis

OBJECTIVE

Temporal bone squamous cell carcinoma (TBSCC) is rare and often confers a poor prognosis. The aim of this study was to synthesize survival and recurrence outcomes data reported in the literature for patients who underwent temporal bone resection (TBR) for curative management of TBSCC. We considered TBSCC listed as originating from multiple subsites, including the external ear, parotid, and external auditory canal (EAC), or nonspecifically from the temporal bone.

DATA SOURCES

PubMed, Cochrane Library, Embase, and manual search of bibliographies.

REVIEW METHOD

A systematic literature review conducted in December 2020 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Survival data were collected from 51 retrospective studies, resulting in a pooled cohort of 501 patients with TBSCC. Compared to patients undergoing lateral TBR (LTBR), patients undergoing subtotal (SBTR) or total (TTBR) TBR exhibited significantly higher rates of stage IV disease (P < .001), positive surgical margins (P < .001), facial nerve involvement (P < .001), and recurrent disease (P < .001). A meta-analysis of 15 studies revealed a statistically significant 97% increase in mortality in patients who underwent STBR or TTBR. On multivariate analysis, recurrent disease was independently associated with worse overall survival (P < .001). On univariate analysis, facial nerve involvement was also associated with decreased overall survival (P < .001).

CONCLUSION

Recurrent disease was associated with risk of death in patients undergoing TBR. Larger prospective multi-institutional studies are needed to ascertain prognostic factors for a wider array of postoperative outcomes, including histology-specific survival and recurrence outcomes.

Auriculotemporal Carcinoma - A Retrospective Case Series

Rationale

Eleven cases with auriculotemporal cancer were reviewed for prognostic analysis.

Patient Concerns

Follow-up ranged from 1.2 to 12 years (median 5.01 years).

Diagnosis Treatment and Outcome

Three patients with parotid gland carcinoma, out of those, two had chemoradiotherapy, died in the first 2 years of treatment. They were at stage T4 and tumour progressed with distant metastasis. Otorrhoea was the most common symptom in patients with primary temporal bone carcinoma. One patient with auricular carcinoma had a recurrence at the primary site 13 months after surgery. One patient with T1, two patients with T2 and one patient with T3 have completed a 5-year survival period. One patient with T1 and another one with T2 are still at a 2-year follow-up period with no recurrence.

Take-Away Lessons

Complete resection is the treatment of choice. Post-operative radiotherapy is highly recommended. The most decisive prognostic indicator is the advanced stage. Early diagnosis has great importance.

Treatment Strategies for Malignancies of the External Auditory Canal

Malignant tumors of the external auditory canal (EAC) are rare tumors in the head and neck. Delayed diagnosis is not uncommon because the symptoms of early tumors are nonspecific. Various surgical and oncological treatment modalities have been reported. Decision-making depends on pathological feature and stage of the lesions, patient’s general condition and preference, and physician’s experience and skill. Radical surgery is widely accepted as the primary treatment of choice. Postoperative radiotherapy is used more often to improve local and regional control of the disease. Chemotherapy is usually recommended for advanced disease, residual disease, and metastasis. Prognosis is affected by multiple factors such as TNM stage, surgical margin, pathological type and differentiation of tumor, involvement of facial nerve, and so on. Although the survival rate is improved significantly over the past several decades with the development of skull base surgery, neuroradiology, anesthesiology, and oncology, it remains challenging to diagnose and treat EAC malignancies due to the rarity, the local anatomical complexity of temporal bone, and the lack of standard TNM staging system.

Surgical treatment for squamous cell carcinoma of the temporal bone: predictors of survival

Objective

Evaluation of the management and survival in patients treated for temporal bone squamous cell carcinoma (TBSCC) in a tertiary referral centre.

Methods

Forty-nine patients underwent primary treatment for TBSCC. Thirty-six patients underwent a lateral temporal bone resection (LTBR) or subtotal temporal bone resection (STBR). Overall survival (OS) and disease-specific survival (DSS) analysis were assessed.

Results

Five-year OS of the 49 patients was 39%. Five-year OS of the 36 patients who underwent LTBR or STBR was 46%. Tumour-free margins were achieved in all patients with T1 and T2 disease, in 59% patients with T3 tumours and 0% patients with T4 disease. Five-year DSS was 85% for all T1/T2 tumours, 53% for T3 tumours and 0% for T4 tumours. Clear resection margins was the only significant predictor of DSS in our cohort.

Conclusions

The mainstay of treatment for TBSCC is temporal bone resection with tumour free resection margins, with or without adjuvant radiotherapy. Survival is negatively influenced by non-radical resection. T1 and T2 tumours can be managed safely with LTBR. More advanced disease requires a more extensive resection, with a higher likelihood of non-radical resections and decreased survival rates.

A systematic review of the primary squamous cell carcinoma of the external auditory canal: survival outcome based on T-staging and proposal of a new classification

OBJECTIVE

This study aimed to provide a systematic review on survival outcome based on Pittsburgh T-staging for patients with primary external auditory canal squamous cell carcinoma.

METHOD

This study was a systematic review in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines performed until January 2018; pertinent studies were screened. Quality of evidence was assessed using the grading of recommendation, assessment, development and evaluation working group system.

RESULTS

Eight articles were chosen that reported on 437 patients with external auditory carcinoma. The 5-year overall survival rate was 53.0 per cent. The pooled proportion of survivors at 5 years for T1 tumours was 88.4 per cent and for T2 tumours was 88.6 per cent. For the combined population of T1 and T2 cancer patients, it was 84.5 per cent. For T3 and T4 tumours, it was 53.3 per cent and 26.8 per cent, respectively, whereas for T3 and T4 tumours combined, it was 40.4 per cent. Individual analysis of 61 patients with presence of cervical nodes showed a poor survival rate.

CONCLUSION

From this review, there was not any significant difference found in the survival outcome between T1 and T2 tumours. A practical classification incorporating nodal status that accurately stratifies patients was proposed.

Management of squamous cell carcinoma of the temporal bone: long-term results and factors influencing outcomes

OBJECTIVE

Temporal bone squamous cell carcinoma (TBSCC) is a rare, aggressive tumor. Surgery, alone or combined with radiotherapy, represent the mainstay of treatment. To report our experience in the treatment of TBSCC and evaluate the disease-specific survival, identifying the factors influencing this outcome.

MATERIALS AND METHODS

A retrospective study was performed on 66 patients between 1993 and 2018. Patients were staged according to the University of Pittsburgh-modified TNM staging system. Nine cases (13.6%) were Stage I, 7 cases (10.6%) Stage II, 20 cases (30.3%) Stage III and 30 cases (45.5%) Stage IV. Twenty-four patients underwent lateral temporal bone resection (LTBR) and 42 patients underwent subtotal temporal bone resection (STBR).

RESULTS

One hundred percent of Stage I and II patients showed no evidence of disease (NED) after a median follow-up of 101 months (range 1-289 months). NED resulted in 88.2% of Stage III (mean follow-up 80.3 months; range 8-257) and 46.4% of stage IV (mean follow-up 50.6 months; range 3-217). Pittsburgh Stage or involvement of mastoid, facial nerve, medial wall of the middle ear, temporomandibular joint and middle fossa dura emerged as negative prognostic factors. The highest mortality rate occurred in the first 2 years after treatment, due to local recurrence.

CONCLUSIONS

Prognosis of TBSCC can be excellent in early stage tumors, employing a LTBR. In more advanced cases, prognosis is poor. STBR with adjuvant radiotherapy represents the treatment of choice, offering acceptable survival rates. Given the rarity of the pathology, many controversies still exist concerning optimal management.

Primary Advanced Squamous Cell Carcinoma of the Temporal Bone: A Single-Center Clinical Study

OBJECTIVES/HYPOTHESIS

The extreme rarity of temporal bone squamous cell carcinoma (TB-SCC) has delayed the accumulation of high-quality clinical evidence. For the purposes of retrospective meta-analysis in the future, a large dataset with information from various institutions would be ideal. Our objective here was to retrospectively review cases of TB-SCC encountered at a single tertiary referral center and explore survival outcomes and prognostic factors.

STUDY DESIGN

Retrospective chart review.

METHODS

The medical records of all TB-SCC cases were retrospectively reviewed. The resulting dataset contained 71 cases of primary cancer eligible for initial definitive (curative) treatment.

RESULTS

T4 status was associated with lower disease-specific 5-year survival than T1 to T3 staging (T1: 100%, T2: 92%, T3: 86%, T4: 51%). Survival was significantly higher in operable than in inoperable cases, even when restricted to advanced (T3/T4) cancers. The tumor extension to the middle ear cavity was observed in 13/17 of T3 cases, but it was not associated with poor survival. In addition, among operable cases, negative surgical margins were associated with significantly higher survival than positive margins.

CONCLUSIONS

Definitive treatments can offer disease-specific 5-year survival of over 85% in T1 to T3 cases of TB-SCC. The tumor extension to the middle ear cavity is not associated with poor survival. T4 status, inoperability, nodal invasion, and positive surgical margin are identified as a predictor of poor prognosis. Still, the matter of how to deal with unresectable tumors remains an outstanding issue in the treatment of TB-SCC.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E583-E589, 2021.

Clinical management for T1 and T2 external auditory canal cancer

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.

LEVELS OF EVIDENCE

4.

The Clinical Characteristics and Surgical Outcomes of Carcinoma of the External Auditory Canal: A Multicenter Study

OBJECTIVE

To analyze the clinical characteristics and evaluate the surgical outcomes of carcinoma of the external auditory canal (CEAC).

MATERIALS AND METHODS

Overall, 31 patients from four multicenter hospitals, who were diagnosed and surgically treated for CEAC in 2009-2014, were enrolled for this retrospective study. Medical records were reviewed to determine cancer stage according to the Pittsburgh classification. Clinical data of age, sex, site, initial symptoms, surgery extent, postoperative complications including recurrence, follow-up period, and current patient status were collected for analysis. Five-year cumulative survival rate was obtained using Kaplan-Meier method.

RESULTS

At initial diagnosis, 22 patients were in the early stages (stage I: 15; stage II: 7) and 9 patients were in the advanced stages (stage III: 1; stage IV: 8). Lymph node metastasis was present in 5 patients and distant metastasis in 2. Of the 31 patients, 4 patients died (stage II: 1, stage IV: 3) during the follow-up period. Early-stage patients showed 100% 5-year estimated cumulative survival rate, whereas the advanced-stage patients showed 5-year estimated survival rate of 53.6% (p=.006). The overall survival rate of all enrolled patients was 90.3%. Although 5-year estimated disease-free survival rate of stage I was 100.0%, that for stage II was low at 30.0% because of considerable recurrences.

CONCLUSION

The results of this multicenter study suggest that more aggressive treatment modality, including adjuvant therapy, is necessary for patients with CEAC with Pittsburgh stage II or more.