HN Cancer Patients with Negative Imaging History Derive Limited Benefit from Subsequent PET-CT

What is the utility of 12- and 24-month PET-CT surveillance in detecting recurrence in patients with head and neck cancer?

Background: The optimal use and timing of PET-CT in the surveillance of patients with head and neck cancer remains a point of debate without clear guidelines. A three-month post-treatment PET-CT scan has a high negative predictive value and is a favorable prognostic factor. In such patients, it is unclear whether further PET/CT surveillance is useful or cost effective.

Study design: Retrospective review of patients with a negative three-month post-treatment imaging who underwent additional subsequent surveillance imaging with PET-CT.

Setting: Stanford University Medical Center, Palo Alto, Calif.

Synopsis: A total of 175 patients met study criteria, with all patients undergoing a 12-month post-treatment PET-CT and 77 patients also undergoing a 24-month post-treatment PET-CT scan. Head and neck tumors were a heterogeneous group, with the oropharynx representing the primary site in 49 percent of patients. At 12 months, PET-CT detected recurrence in 15 patients (9 percent), two of which were local, three regional and 10 distant. At 24 months, PET-CT detected recurrent disease in three patients (4 percent), all of whom had distant disease. Locoregional recurrence was identified in 13 patients (5 percent) on clinical grounds alone during the study period, in six patients during the three- to 12 month post-treatment interval and in seven patients in the 12- to 24-month interval, all of whom had previously had negative imaging. Salvage surgery was performed in 89 percent of all patients with locoregional recurrence. There was no significant difference in three-year overall survival and disease-specific survival rates between patients whose recurrence was detected by PET-CT (60 percent and 40 percent) and patients whose recurrence was detected by clinical examination (54 percent and 46 percent).

Bottom line: Head and neck cancer patients with negative three-month imaging appear to derive limited benefit from subsequent routine PET-CT surveillance. No survival advantage was demonstrated for patients with PET-CT-detected recurrence compared to those detected clinically.

Citation: Ho AS, Tsao GJ, Chen FW, et al. Impact of positron emission tomography/computed tomography surveillance at 12 and 24 months for detecting head and neck cancer recurrence. Cancer. 2013;119:1349-1356.

—Reviewed by Christine G. Gourin, MD