Otolaryngology, ENT Conference

Biography

Anders Sideris is the Otolaryngology/ Head and Neck Research Fellow at Prince of Wales Hospital in Sydney Australia. He has particular research interests in the field of Head and Neck Oncology, the nexus of biomedical engineering and surgery and is currently involved in early work developing novel methods for sustained local drug delivery in Otolaryngology.

Abstract

Acinic cell carcinoma is a malignant epithelial neoplasm of the salivary glands that classically follows an indolent clinical course. However, presentation can be variable and a high-grade variant has been associated with higher chance of metastasis and poorer survival outcomes. Surgical treatment is generally curative but there is little consensus as to the benefit of radiotherapy in this disease. The aim of this research was to characterise the experience of three major hospitals in Sydney, Australia with a focus on clinico-pathologic features of disease and their associations with morbidity and survival outcomes.

 

Methods: Cases of acinic cell carcinoma in the time period 1979 to 2018 were identified in the hospital medical records and oncology databases at all institutions. Patients’ medical records were reviewed for baseline demographics, clinical data (including TNM staging data), treatment and survival data. Formal histopathology slides were reviewed by a consultant pathologist, and data on key pathological features were collected.

 

Results: Thirty-two cases were pooled for analysis (29 adult and 3 paediatric). Thirty tumours (93.8%) were parotid primary tumours. Mean overall survival (± SEM) for the entire cohort was 16.9 ± 0.75 years and 96.9% at final follow up. Mean disease free survival was 15.58 ± 1.0 years and 93.8% at final follow up. Multiple pathological phenomena were associated with poorer survival including presence of >2 mitoses per 10 HPF (p=0.008), high-grade disease (p=0.006), focal necrosis (p=0.008), perineural invasion (p=0.031) and higher nuclear grade (p=0.029). cT staging >1 (primary tumour greater than 2cm in diameter) (p=0.04), presence of clinical facial nerve deficit (p=0.025), tumour involvement of both superficial and deep lobes of the salivary gland (p=0.03) and extra-organ spread as defined by spread to non salivary gland tissue (p=0.018) were also associated with mortality. Clinical facial nerve deficit (p=0.048), perineural invasion (p=0.019) and extra organ spread (p=0.02) were associated with recurrence.

Conclusion: Our results suggest that disease free and overall survival in acinic cell carcinoma of the salivary gland is generally favourable and in the majority of cases is adequately treated with surgical resection alone. Poor survival outcomes are predicted by primary tumour size (>2cm in diameter), preoperative facial nerve deficit, extra organ spread, involvement of both lobes of the parotid gland and pathologic features of high-grade disease.