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What Is the Best Timing for Endoscopic and Radiographic Surveillance Following Sinonasal Malignancies Treatment?

by Arjun K. Parasher, MD, MPhil, Edward C. Kuan MD, MBA, Maie A. St. John MD, PhD, Bobby A. Tajudeen MD, and Nithin D. Adappa, MD •

TRIO Best PracticeTRIO Best Practice articles are brief, structured reviews designed to provide the busy clinician with a handy outline and reference for day-to-day clinical decision making. The ENTtoday summaries below include the Background and Best Practice sections of the original article. To view the complete Laryngoscope articles free of charge, visit Laryngoscope.

Background

Sinonasal malignancies are rare, representing only 3% of all head and neck neoplasms and approximately 1% of all malignancies. Given this low incidence and the diversity of pathologies, standardized protocols for post-treatment surveillance are lacking. Due to their advanced stage at presentation, sinonasal malignancies often have a poor prognosis, with recurrence rates ranging from 27% to 56%. Whereas the majority of recurrences occur within two to three years post-treatment, certain malignancies, such adenoid cystic carcinoma, olfactory neuroblastoma, and melanoma, have a propensity to recur much later. The majority of recurrences occur locally and represent the leading cause of disease-specific mortality. Several factors, including complex anatomy, treatment-related changes, distortion due to resection and reconstruction, and sinonasal inflammation, complicate surveillance for recurrence. Due to these unique aspects, accepted surveillance guidelines for head and neck malignancies may not be directly applicable for sinonasal malignancies. Accordingly, distinct guidelines for post-treatment endoscopic and radiographic surveillance are needed.

Best Practice

Given the high recurrence rates in sinonasal malignancies, close, routine endoscopic and imaging surveillance is needed in the post-treatment setting. Endoscopy and imaging serve to complement each other.

Frequent endoscopic examinations can be completed at one- to three-month intervals, with MRI imaging at three- to six-month intervals for the first 24 months. Beyond this period, endoscopic examinations can be performed every three to six months until year five and then annually thereafter, whereas imaging can be performed every six months to yearly. PET/CT imaging can be deferred between six and 12 months post-treatment in most cases. However, PET/CT has a unique role in tumors such as melanoma with propensity for distant metastasis or to better characterize equivocal findings on MRI beyond four months post-treatment. Ultimately, given the lack of level 1 evidence, endoscopic and imaging surveillance protocols should be left to clinical judgment given individual patient factors, tumor biology, and treatment modalities (Laryngoscope. 2018;128:1511–1512).