What is the recommended treatment for sinonasal adenocarcinoma?

Treatment of Sinonasal Adenocarcinoma

The recommended treatment for sinonasal adenocarcinoma is surgical resection followed by postoperative radiotherapy, with the surgical approach determined by what will best allow complete excision of the tumor. 1

Diagnostic Evaluation

• Complete imaging evaluation is essential for proper staging and treatment planning:

  • MRI maxillofacial without and with IV contrast is the primary imaging modality, complemented by CT paranasal sinuses without contrast 2
  • CT paranasal sinuses without IV contrast is necessary to evaluate bone erosion or destruction 2
  • CT chest with IV contrast should be performed to evaluate for pulmonary metastases 2

• PET/CT may be indicated if malignancy is suspected to help with staging 2

Surgical Management

• Surgery is the mainstay of treatment for sinonasal adenocarcinoma 3, 1

• The surgical approach should be determined by what will best allow complete tumor excision:

  • Craniofacial resection (CFR) is often required for advanced disease and has been correlated with better overall survival and disease-specific survival 3
  • Endoscopic techniques may be used if complete tumor removal can be achieved, offering comparable results to external approaches with lower morbidity 1, 4
  • Transfacial approaches may be necessary depending on tumor location and extent 3

• Complete surgical resection with negative margins is the goal, with margins checked by frozen section if necessary 4

Adjuvant Treatment

• Postoperative radiotherapy should be administered in most cases, ideally within six weeks after surgery 4
• Radiotherapy should be delivered within an accredited department using megavoltage photons from a linear accelerator 4
• The addition of postoperative radiotherapy for advanced cases can achieve local control rates comparable to those of less advanced cases treated with surgery alone 1

Prognostic Factors

• Several factors affect prognosis in sinonasal adenocarcinoma:
  • Age over 60 years is a negative prognostic factor 3
  • Tumors with maxillary origin have worse prognosis 3
  • Microscopic bone invasion is associated with poorer outcomes 3
  • Tumor grade (intermediate/high) affects survival 3
  • Advanced T stage (T3/T4) is associated with worse outcomes 3

Treatment Outcomes

• With appropriate multimodality treatment, favorable outcomes can be achieved:
  • Overall survival rates of 90%, 68%, and 54% at 2,5, and 10 years respectively 3
  • Disease-specific survival rates of 90%, 73%, and 58% at 2,5, and 10 years 3

Special Considerations

• Treatment should be carefully planned and discussed at a specialist skull base multidisciplinary team meeting with all relevant expertise 4
• For locally advanced and/or metastasized disease, systemic treatment options (chemotherapy, targeted agents, or immunotherapy) are less standardized and require further research 5
• Patients with sinonasal cancer should be treated in clinical referral centers specializing in skull-base pathologies 6

Common Pitfalls and Caveats

• Delayed diagnosis is common due to nonspecific symptoms in early stages, leading to advanced disease at presentation 2, 6
• Proximity to critical neurovascular structures makes treatment complex and can lead to high morbidity 6
• Incomplete surgical resection significantly reduces survival outcomes, emphasizing the importance of achieving negative margins 3, 4
• Radiation therapy should not be delayed beyond six weeks after surgery to ensure optimal outcomes 4