Treatment Strategies for Malignancies of the External Auditory Canal

The Naples Prognostic Score Exerts a Significant Impact on the Prognosis of Patients Diagnosed with External Auditory Canal Carcinoma After Surgery

Background

External auditory canal carcinoma (EACC) is a rare malignant tumor. This study aimed to investigate the influence of the comprehensive index of nutrition- Naples prognostic score (NPS) on the prognosis of EACC patients with surgical resection.

Methods

A total of 73 EACC patients with surgical resection were selected from two tertiary medical institutions, and were diagnosed between Sep 2008 and Aug 2019. The univariate and multivariate Cox regression analyses were used to identify the independent prognostic factors for disease-free survival (DFS) and overall survival (OS) for postoperative EACC patients. The prognosis for postoperative EACC patients with varying NPS were displayed by Kaplan-Meier plots.

Results

The 3- and 5-year survival rate for EACC patients with surgical resection were 72.6%, 32.9% for DFS, and 76.7%, 52.1% for OS, respectively. The multivariate Cox regression analysis revealed that advanced Pittsburgh stage, perineural invasion, vascular invasion, and higher NPS were identified as independent prognostic factors for DFS. Additionally, advanced Pittsburgh stage, vascular invasion, an ACCI score of 6 or higher, and higher NPS were found to be independent predictors for OS.

Conclusion

NPS serves as a crucial predictor of postoperative outcomes in patients with EACC, with higher levels indicating poorer disease-free and overall survival. Additionally, factors such as Pittsburgh stage, perineural and vascular invasion, and ACCI are also significant prognostic indicators.

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.

Development and validation of a nomogram to predict overall survival in patients with External auditory canal cancer

AIM

We aimed to examine the influence of various prognostic factors on the outcome of external auditory canal (EAC) cancer and create a graphical prediction tool, marking a first in this field, premised on these determinants.

METHODS

We retrospectively analysed 173 patients with EAC cancer, making this the largest patient cohort in the literature. Survival analysis was performed using the Kaplan-Meier method, and the log-rank test was used to assess the differences between established prognostic variables. The risk factors for overall survival (OS) rates were analysed by univariate and multivariable Cox regression analyses.

RESULTS

The cohort demonstrated 2-, 5-, and 10-year progression-free survival (PFS) rates of 86.9%, 72.7%, and 60.1%, respectively. The overall survival (OS) rates for the cohort at 2, 5, and 10-years were 93.6%, 80.6%, and 65.8%, respectively. The key predictors of both OS and PFS were squamous cell carcinoma, T stage, margin status, and radiotherapy. The nomogram showed good predictive accuracy and discriminative ability. Post-radiotherapy follow-up data indicated that the incidence rates of allotriogeustia, saprodontia, xerostomia, difficulty in opening the mouth, and facioplegia were 1.3%, 6.5%, 22.7%, 8.4%, and 3.2%, respectively.

CONCLUSION

Our findings highlight the significance of squamous cell carcinoma, T stage, margin status, and radiotherapy as predictors of OS and PFS. Validation analysis confirmed the applicability of the developed nomogram in predicting individual survival probabilities for patients with EAC cancers, signifying a notable progression in the diagnosis and treatment of EAC cancers.

Radiologic evaluation of the internal carotid artery and jugular bulb in lateral temporal bone resection using 3D computed tomography

PURPOSE

This study investigated the internal carotid artery (ICA) and jugular bulb (JB) structures in terms of lateral temporal bone resection using 3D computed tomography (CT).

METHODS

We retrospectively investigated 80 ears of 40 patients using 3D reconstruction data from normal temporal bone CT. Ten critical points (P) in the temporal bone were marked in the 3D object with reference to the axial, coronal, and sagittal images of the CT scans. An imaginary plane of the facial nerve (PLf) course was also reconstructed in relation to the three points of the chorda-facial junction, P5 (second genu), and P3 (cochleariform) process.

RESULTS

The distances (mean ± SD; mm) from points P3 to P1 (the highest level of the JB) and P2 (the posterior wall of the ascending petrous IAC at the level of the Eustachian tube) were 12.03 ± 2.56 and 9.79 ± 1.78, respectively. The distances from point P4 (chorda-facial junction) to P1 and P2 were 10.98 ± 2.70 and 17.66 ± 2.26, respectively. The angles (mean ± SD; degree) between the PLf to the line from Pa (point of the anterior bony canal) to P3 and P4 were 17.80 ± 10.05º and 8.93 ± 5.37º, respectively. The angles between the PLf to the line from P3 to P1 and P2 were - 36.35 ± 13.28º and - 24.78 ± 13.91º, respectively. The angles between the PLf to the line from P4 to P1 and P2 respectively were - 40.35 ± 15.37º and - 13.34 ± 7.63º.

CONCLUSIONS

Understanding the anatomical relationships of P1 and P2 at P3 and P4 can be helpful in preventing iatrogenic trauma of the ICA and JB.

Malignant tumors of the external auditory canal: diagnosis, treatment, genetic landscape, biomarkers, and clinical outcome

Malignant tumors of the external auditory canal (EAC) are rare neoplasms that appear in the head and neck area. A common feature of these malignancies is their rarity, as well as their delayed diagnosis due to the appearance of non-specific symptoms that mimic various benign otologic conditions. The reported histological types of cancer of the external ear are: squamous cell carcinoma, basal cell carcinoma, malignant melanoma, Merkel cell carcinoma, angiosarcoma, adnexal carcinoma (including ceruminous adenocarcinoma and adenoid cystic carcinoma), and lymphoma (Lancet Oncol. 2005;6:411-20. doi: 10.1016/S1470-2045(05)70208-4). Several therapeutic interventions have been proposed, primarily orientated towards the cure of the patient, placing the surgical excision of the lesions at the tip of the spear. Subsequently and depending on the clinical stage and the pathological characteristics of the tumor, radiation, chemotherapy, a combination thereof, or some form of palliative treatment for particularly advanced cases, may be recommended. The aim of all the above-mentioned approaches is the complete resection of the mass with negative surgical margins along with lymph node dissection, the elimination of any residual disease or metastasis, and the improvement of survival. The anatomical complexity of the region will always remain a demanding challenge. Nevertheless, advances in the fields of ear microsurgery, imaging, radiation, molecular biology, and genomics have led to remarkable outcomes compared to the past, with a view to the patient's quality of life. Large, well-organized, and prospective studies with the participation of multiple centers in contrast to existing retrospective studies with a limited number of patients will help to establish universally accepted guidelines. The exploration of the molecular and genetic background of these cancers in conjunction with the search for new biomarkers and target molecules seems promising for providing upgraded and more personalized treatment modalities for the future.

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.

[Current status of the diagnosis and treatment of temporal bone squamous cell carcinoma]

Temporal bone squamous cell carcinoma, which is rare in the clinical setting, is the most common type of temporal bone malignancy. Its rarity makes the staging, the way of temporal bone resection, the management of parotid gland and cervical lymph node, and the application of radiotherapy and chemotherapy still controversial.There is no unanimous consensus and guideline about it to date at home and abroad.This paper reviewed the recent advance in the diagnosis and treatment of temporal bone squamous cell carcinoma in the hope of providing some help and reference for the management of the disease.