Fdg-Pet Scan in Local Follow-up of Irradiated Head and Neck Squamous Cell Carcinomas

Abstract

We performed a prospective study to assess the value of positron emission tomography (PET) with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) in the prediction of local control in irradiated head and neck squamous cell carcinomas (HNSCCs). Forty-two patients with irradiated HNSCCs underwent 49 FDG-PET scans between 3 and 6 months after the end of radiotherapy. The mean follow-up time after the first FDG-PET scan was 17 months. The result of the FDG-PET scan was true-positive in 6 patients, false-positive in 7 patients, and true-negative in 29 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of FDG-PET scanning were 100%, 81%, 46%, and 100%, respectively. We conclude that FDG-PET scanning is useful for prediction of therapy outcome in irradiated HNSCCs. No biopsy is needed for at least 1 year if an FDG-PET scan is negative. If the scan is positive and the biopsy is negative, decreased FDG uptake measured in a follow-up scan indicates that a local recurrence is unlikely.

Utility of Positron Emission Tomography‐Computed Tomography in Identification of Residual Nodal Disease after Chemoradiation for Advanced Head and Neck Cancer

“…PET is able to detect residual nodal disease in patients with a partial response to CR with a reported sensitivity of 71% to 100%, specificity of 43% to 100%, positive predictive value of 46% to 100%, and negative predictive value of 66% to 100% 23,24,26–30 . The efficacy of PET in detecting residual or recurrent disease depends on the timing of PET imaging after treatment.…”

Positron emission tomography–CT prediction of occult nodal metastasis in recurrent laryngeal cancer

“…The 2‐[fluorine‐18]fluoro‐2‐deoxy‐d‐glucose (FDG) positron emission tomography (PET), in combination with CT (PET‐CT), is increasingly being used in the management of patients with head and neck cancer, including initial staging, assessing response to therapy, detecting recurrence, and identifying unknown primary tumors . Additionally, PET‐CT is increasingly used to improve the accuracy of staging in recurrent laryngeal cancer .…”

PET in face and neck tumours

“…The timing after radiotherapy (RT) is also important, scans which are positive after 4 weeks indicate residual disease, but a negative scan is unreliable with a NPV of 14% [27], however a scan at 4 months may more accurately reflect disease with a negative predictive value of 100%, suggesting that no biopsy will be needed for at least one year if the PET is negative [28]. Greven et al [29] found FDG-PET useful for the initial imaging of head and neck cancer but the initial SUV did not predict response to RT, and the 1 month post-RT scan was inaccurate (35% false negative) with the 4-month post-RT scan a better predictor for the presence of residual tumour.…”