Impact of postoperative FDG-PET/CT on adjuvant head and neck cancer treatment.

Abstract

Background: Residual or recurrent cancer after surgery but prior to adjuvant therapy occurs in a proportion of patients with head and neck cancer and may warrant treatment changes. 18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) may help identify residual or recurrent disease but is not routinely obtained. We evaluated the relevance of postoperative FDG-PET/CT in this clinical context.

Methods: This single-institution, retrospective study identified patients with head and neck cancer who underwent definitive surgery between January 1, 2013, and April 1, 2023, and received a postoperative FDG-PET/CT prior to adjuvant treatment. We measured the rates of management changes resulting from postoperative FDG-PET/CT findings and the association between having a postoperative FDG-PET/CT which resulted in a management change and oncologic outcomes with selected multivariable competing-risks and proportional hazards regressions.

Results: Of 150 patients, sixty-six (44.0%) had a management change because of the postoperative FDG-PET/CT findings. Sixty-two (93.8%) had radiotherapy plan changes, 20 (30.3%) underwent additional diagnostic testing, 11 (16.7%) had systemic therapy added or changed, 3 (4.6%) underwent reresection, and 15 (10.0%) switched to palliative-intent treatment. Having a postoperative FDG-PET/CT which resulted in a management change was not significantly associated with cancer recurrence or overall survival (both p > .05).

Conclusion(s): In patients with resected head and neck cancer, postoperative, pre-adjuvant therapy FDG-PET/CT can alter clinical management and may enable additional personalization of treatment. When practical to obtain without delaying treatment, postoperative FDG-PET/CT may have clinical utility though requires careful interpretation due to the risks of false positives.