Head and Neck Cancer - 58-year-old gentleman

HISTORY:
This is a 58-year-old gentleman who had previously undergone chemoradiation for a base of tongue squamous cell carcinoma. He had good response initially; however, at a follow-up a year later, he was noted to have a recurrence. This was proven by biopsy, and he was referred for further evaluation. On examination, he was noted to have a 2 cm mass in his right base of tongue, as well as 40-pound weight loss. He was referred for a PET•CT scan for evaluation of recurrent disease.


IMAGING FINDINGS BEFORE TREATMENT:
There was focal, moderately increased FDG uptake in the upper portion of the right paraglottic fat in the right larynx, consistent with recurrent tumor. There was slight increase of soft tissue around the right carotid sheath which showed only minimal uptake, most consistent with post-radiation changes.


IMAGING FINDINGS FOLLOW-UP SCAN:
The increased FDG uptake corresponding to the right paraglottic fat described and seen on the previous PET•CT scan was no longer evident. There was no abnormal FDG uptake to suggest the presence of FDG avid malignancy on the current study.

DISCUSSION:
This case shows a nice example of a patient who appears to have responded well to radiation therapy. The follow up scan was performed 7 weeks after radiation. In general, we like to wait 6-8 weeks following radiation therapy to avoid a false positive study due to radiation induced inflammatory FDG uptake. If the radiation involves the lung, we typically wait 3-4 months because of the lung's increased sensitivity to the effects of radiation.

Data courtesy of Dr. Todd Blodgett, University of Pittsburgh Medical Center