What is the treatment for adenoid cystic carcinoma (ACC) in the nasal cavity?

Treatment of Adenoid Cystic Carcinoma in the Nasal Cavity

The optimal treatment for adenoid cystic carcinoma (ACC) of the nasal cavity is radical surgical resection followed by postoperative radiation therapy, as this approach offers the best outcomes for morbidity, mortality, and quality of life. 1

Initial Assessment and Staging

• Complete head and neck examination with nasal endoscopy
• Imaging studies:
  • CT and MRI to assess local extent and perineural invasion
  • Chest CT for distant metastasis evaluation (lungs are common metastatic site)
• Biopsy for histopathological confirmation and grading
• Evaluation for skull base or orbital involvement

Treatment Algorithm

Primary Treatment

1. Surgical Resection

   • Endoscopic endonasal approach for selected cases 2
   • Open craniofacial resection for extensive disease with skull base involvement
   • Goal: complete resection with negative margins
   • Ipsilateral neck dissection for T3-T4 tumors or high-grade malignancies 1

2. Postoperative Radiation Therapy

   • Should be offered to ALL patients with resected ACC regardless of stage 1
   • Dose: 60-70 Gy in standard fractions
   • Target volume: surgical bed and appropriate nodal levels
   • If perineural invasion present: cover associated nerve(s) to skull base 1

Special Considerations

• For unresectable disease: Definitive radiation therapy with or without concurrent chemotherapy 1
• For recurrent disease: Consider revision surgery when feasible, followed by re-evaluation for adjuvant therapy 1
• For metastatic disease with limited metastases (≤5): Consider local ablative treatments (surgery or stereotactic body radiation therapy) 1

Prognostic Factors and Outcomes

• Negative prognostic factors:

  • Positive surgical margins
  • Perineural invasion
  • High-grade histology
  • Advanced T-stage
  • Ki-67 expression (higher values associated with treatment failure) 3

• Expected outcomes:

  • 5-year overall survival: 62.9-86.5% 2, 4
  • Local recurrence rate: 30% 4
  • Distant metastasis rate: 38% 4

Follow-up Recommendations

• Regular clinical examinations of nasopharynx and neck
• Evaluation of cranial nerve function
• Imaging surveillance:
  • Consider imaging at 3 months post-treatment
  • Yearly imaging for 12-24 months
  • Extended surveillance beyond 5 years due to late recurrences 1
• Chest CT yearly for initial 2 years, then extended as needed (ACC has high rate of late pulmonary metastases) 1

Important Caveats

• ACC is characterized by slow growth but high propensity for perineural invasion and late distant metastases
• Standard chest X-ray lacks sensitivity for detecting pulmonary metastases and should not be used 1
• Despite metastatic disease, 10% of patients with ACC can survive more than 10 years 1
• Conventional chemotherapy has limited efficacy for metastatic disease
• Clinical trials should be considered when available, particularly for advanced or recurrent disease

The combination of surgery and radiation therapy has consistently demonstrated superior outcomes compared to either modality alone, with endoscopic approaches showing promising results in selected cases while reducing morbidity compared to open approaches 2.