Adenoid Cystic Carcinoma

Area of Science:

• Oncology
• Head and Neck Surgery
• Radiation Oncology

Background:

• Sinonasal adenoid cystic carcinoma (SACC) is a rare malignancy with insidious growth.
• Perineural spread is common, leading to skull base invasion and advanced disease at presentation.
• Treatment is challenging due to involvement of critical structures, often causing high morbidity.

Purpose of the Study:

• To review the current understanding of sinonasal adenoid cystic carcinoma.
• To discuss the primary treatment modalities, including surgery and radiotherapy.
• To highlight the importance of long-term follow-up due to late recurrences and metastases.

Main Methods:

• Review of existing literature on sinonasal adenoid cystic carcinoma.
• Analysis of treatment strategies, focusing on surgical resection and radiotherapy.
• Evaluation of prognostic factors and survival outcomes.

Main Results:

• Complete surgical resection with negative margins offers the best survival outcomes.
• Adjuvant radiotherapy is recommended due to high rates of local failure and spread.
• Heavy-particle radiotherapy (protons, carbon ions) shows promise for improved local control.
• 5-year survival is 55-70%, but drops significantly at 10 (40%) and 20 (15) years.

Conclusions:

• Surgical management is the mainstay, with function-preserving options for unresectable cases.
• Adjuvant radiotherapy, especially heavy-particle therapy, is crucial for managing SACC.
• Prolonged, lifelong follow-up is mandatory due to the high incidence of late recurrences and metastases.