FDG-PET/CT in the Assessment of Treatment Response after Oncologic Treatment of Head and Neck Squamous Cell Carcinoma
the Cancer Therapy Advisor take:
In this article from Clinical Medicine Insights: Ear, Nose and Throat, investigators from Helsinki, Finland, examined the effectiveness of 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in detecting residual disease after definitive chemotherapy and radiotherapy [(C)RT] for squamous cell carcinoma of the head and neck (HNSCC).
Of the patients with HNSCC at the researchers' institution who received FDG-PET/CT to evaluate treatment response 10 to 18 weeks after (C)RT , 88 were determined to be eligible for this retrospective study based on review of hospital records. The stage distribution of these patients was stage I: n=1; stage II: n=15; stage III, n=17; stage IV, n=55. The negative predictive value of FDG-PET/CT was 87%; positive predictive value, 81%; specificity, 94%; sensitivity, 65%; and accuracy, 85%.
The authors determined from the results that post-treatment FDG-PET/CT for patients who have received definitive (C)RT for HNSCC has good potential to aid in clinical decision making, meaning that patients with a positive scan should receive a tissue biopsy or neck dissection to rule out residual disease.
It is worth noting that the limitations of this study are the small size of the patient group and the retrospective nature; however, there are only a few previous studies on this specific topic that have had larger cohorts. The authors state that further comparative studies about the best imaging modality in this setting need to be performed in order to clarify this issue.
FDG-PET/CT usefulness remains controversial.
BACKGROUND: In many centers, 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) is used to monitor treatment response after definitive (chemo)radiotherapy [(C)RT] for head and neck squamous cell carcinoma (HNSCC), but its usefulness remains somewhat controversial. We aimed at assessing the accuracy of FDG-PET/CT in detecting residual disease after (C)RT.
METHOD: All HNSCC patients with FDG-PET/CT performed to assess treatment response 10–18 weeks after definitive (C)RT at our institution during 2008–2010 were included. The patient charts were reviewed for FDG-PET/CT findings, histopathologic findings, and follow-up data. The median follow-up time for FDG-PET/CT negative patients was 26 months.
RESULTS: Eighty-eight eligible patients were identified. The stage distribution was as follows: I, n = 1; II, n = 15; III, n = 17; IV, n = 55. The negative predictive value, positive predictive value, specificity, sensitivity, and accuracy of FDG-PET/CT in detecting residual disease were 87%, 81%, 94%, 65%, and 85%, respectively. The corresponding specific figures for the primary tumor site were 91%, 71%, 94%, 59%, and 86% and for the neck 93%, 100%, 100%, 75%, and 94%, respectively.
CONCLUSIONS: In patients who have received definitive (C)RT for HNSCC, post-treatment FDG-PET/CT has good potential to guide clinical decision-making. Patients with negative scan can safely be followed up clinically only, while positive scan necessitates tissue biopsies or a neck dissection to rule out residual disease.
KEYWORDS: FDG-PET/CT, head and neck squamous cell carcinoma, HNSCC, chemoradiotherapy, response assessment
CITATION: Keski-säntti et al. Fdg-Pet/Ct in the assessment of treatment response after oncologic treatment of head and neck squamous Cell Carcinoma. Clinical Medicine Insights: Ear, Nose and Throat 2014:725 –729. doi:10.4137/CMent.s16399.
RECEIVED: april 23, 2014. RESUBMITTED: June 7, 2014. ACCEPTED FOR PUBLICATION: June 8, 2014.
ACADEMIC EDITOR: Brenda Anne Wilson, editor in Chief
TYPE: original research
FUNDING: authors disclose no funding sources.
COMPETING INTERESTS: Authors disclose no potential conflicts of interest.
This paper was subject to independent, expert peer review by a minimum of two blind peer reviewers. all editorial decisions were made by the independent academic editor. all authors have provided signed confirmation of their compliance with ethical and legal obligations including (but not limited to) use of any copyrighted material, compliance with ICMJE authorship and competing interests disclosure guidelines and, where applicable, compliance with legal and ethical guidelines on human and animal research participants. the preliminary results of this study were presented at the 5th european Conference on head and neck oncology, Poznan, Poland, april 18–21, 2012.