Unilateral FDG-Avid Tonsil (or Relative Increased Avidity of One Tonsil)

Special care is required when assessing the incidental finding of a unilateral hot tonsil (or relative increased uptake within one tonsil) — even though most unilateral hot tonsils are benign. 

Proposed techniques for assessment have included SUV threshold cutoff values, metabolic tumor volume assessment, and SUV ratios.

Unfortunately, we believe it is advisable to raise at least a degree of concern for all FDG-avid unilateral tonsillar findings.   The level of suspicion, of course, depends on the presentation.  

At PETCTMD, we utilize the following practical approach for the incidental finding of a unilaterally FDG-avid tonsil.

Application of this algorithm (including case examples) is covered in detail in the Tonsillar Carcinoma section, here.

1. NON-ENLARGED AND:
   1. Unilaterally Avid (≥ Liver Uptake)
   2. OR
   3. Uptake “Unquestionably” > Contralateral Tonsil
2. UNILATERALLY ENLARGED AND:
   1. Unilaterally Avid (≥ Liver Uptake)
   2. OR
   3. Uptake “Unquestionably” > Contralateral Tonsil
3. ANY UNILATERAL TONSILLAR UPTAKE ASSOCIATED WITH HYPERMETABOLIC CERVICAL NODES.