The prognostic value of FDG PET in head and neck cancer. Correlation with histopathology

The aim of the present FDG PET study was to evaluate the prognostic value of the standardized uptake value (SUVmax) of head and neck cancer (HNSCC) with respect to the chemotherapy response and tumor recurrence.

The FDG PET findings of 40 patients with HNSCC were compared with the final histopathology results after removal of the primary tumor and surgical neck dissection. The clinical T staging was based on clinical examinations and computed tomography was used for assessment of bone involvement. The pretreatment baseline SUVmax of the primary tumor were correlated with the intra-arterial chemotherapy response prior to the tumor resection and the frequency of tumor relapse.

The median SUVmax of tumors which did not relapse was 3.4, compared to a SUVmax of 4.7 for tumors with local tumor relapse (p=0.36, n.s.). Regarding chemotherapy response, the tumor SUVmax was significantly lower in cases with complete remission (CR) (median 2.6, n=11) compared to those with stable disease (5.8, n=10), (p=0.002). Whereas no tumor with CR after chemotherapy relapsed except stage IV tumors, tumor relapse was observed in both a stage II and a stage IV tumor without chemotherapy response.

In patients with HNSCC the tumor SUVmax seems to be a useful prognostic indicator for assessing the clinical chemotherapy response, but did not correlate significantly with the recurrence risk. Thus, in tumors with higher SUVmax alternative chemotherapy regimes have to be discussed.