Pilot Study of 99mTc-labeled Ethylene Dicysteine Deoxyglucose SPECT-CT Imaging in Treatment Response Evaluation in Patients with Locally Advanced Head and Neck Cancer

Cureus. 2017 Apr 11;9(4):e1152. doi: 10.7759/cureus.1152.

Abstract

Background: The purpose of this study is to describe the preliminary findings of 99mTc-labeled ethylene dicysteine deoxyglucose (99mTc-EC-DG) performed four weeks after chemoradiotherapy in patients with locally advanced head and neck squamous cell carcinoma.

Methods: Review of nine patients with locally advanced head and neck squamous cell carcinomas imaged with 99mTc-EC-DG single photon emission computed tomography-computed tomography (SPECT-CT) at baseline before treatment and at four weeks after treatment completion was performed.

Results: At four weeks post-treatment, five patients had either decreased activity or no significant activity on 99mTc-EC-DG SPECT-CT and were considered to have responded to treatment, whereas four patients did not have significantly decreased uptake on 99mTc-EC-DG SPECT-CT and were considered to have not adequately responded to treatment. Among the five patients considered to have treatment response at four weeks, all were free of disease (true-negative). Among the four patients considered to have stable activity on 99mTc-EC-DG SPECT-CT at four weeks, two were designated as having no response or incomplete response (true-positive), and two were designated as having complete response (false-positive) on subsequent composite assessment.

Conclusions: The pilot data is promising but warrants further investigation of 99mTc-EC-DG SPECT-CT for the assessment of locoregional treatment response at four weeks in patients with locally advanced head and neck squamous cell carcinomas.

Keywords: 99mtc-ec-dg spect-ct; chemoradiation; head and neck; recurrence; squamous cell carcinoma.