Positron emission tomography with 18F-fluorodeoxyglucose to predict pathologic response after induction chemotherapy and definitive chemoradiotherapy in head and neck cancer

Abstract

Background: Conventional imaging is limited in identifying persistent disease after organ-preserving therapy for patients with advanced squamous cell carcinoma of the head and neck (SCCHN). We studied the accuracy of positron emission tomography (PET) with (18)F-fluoro-2-deoxy-D-glucose (FDG-PET) in restaging disease in patients with SCCHN after they had undergone induction chemotherapy (ICT) followed by chemoradiotherapy (CRT).

Methods: Forty patients with advanced SCCHN were treated with ICT followed by CRT. FDG-PET imaging was performed to assess for residual cancer at the primary site and in nodal metastases. Two nuclear medicine physicians interpreted PET scans in random sequence. Test characteristics were calculated with pathologic analysis or clinical recurrence as the standard.

Results: After induction chemotherapy, PET imaging had a sensitivity of 100% and specificity of 65% for detecting persistent disease at the primary tumor site. After ICT and CRT were completed, the sensitivity and specificity of PET imaging were 67% and 53%, respectively, for detecting occult disease in cervical lymph nodes.

Conclusions: FDG-PET imaging showed some correlation with pathologic response after ICT and CRT in patients with advanced SCCHN. The use of FDG-PET warrants further investigation in this setting.