Accuracy of (18) FDG PET-CT for treatment evaluation 3 months after completion of chemoradiotherapy for head and neck squamous cell carcinoma: 2-year minimum follow-up.

The purpose of this study was to assess the accuracy of (18) F-fluorodeoxyglucose positron emission tomography ((18) FDG PET)-CT in detecting residual or recurrent disease after nonsurgical treatment for head and neck squamous cell carcinoma (HNSCC). We conducted a retrospective analysis of patients with oral cavity, oropharynx, larynx, hypopharynx, or cervical lymph node location of SCC treated with chemoradiotherapy. Twelve weeks posttreatment, (18) FDG PET-CT results were compared to histology if residual disease was suspected. Patients with complete response received a minimum of 24-month follow-up. Forty-seven patients were included with 40 months of median follow-up: 46 with a squamous cell carcinoma (SCC) at the primary site and 43 in the neck. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.7%, 90%, 76.5%, and 93.1%, respectively, at the primary site and 100%, 97.2%, 87.5%, 100%, respectively, in the neck. (18) FDG PET-CT seems effective in detecting residual disease and in predicting recurrent disease within the first 2 years of follow-up after nonsurgical treatment. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1271-E1276, 2016.

Sagardoy T ，Fernandez P ，Ghafouri A ，Digue L ，Haaser T ，de Clermont-Galleran H ，Castetbon V ，de Monès E ... -  《-》

Use of Diffusion-Weighted Imaging and (18)F-Fluorodeoxyglucose Positron Emission Tomography Combined With Computed Tomography in the Response Assessment for (Chemo)radiotherapy in Head and Neck Squamous Cell Carcinoma.

Our purpose was to assess the diagnostic accuracy and prognostic value of diffusion-weighted imaging (DWI) and 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG-PET/CT) carried out 3-6 months after (chemo)radiotherapy in head and neck squamous cell carcinoma. For this retrospective cohort study we included 82 patients with advanced-stage head and neck squamous cell carcinoma treated between 2012 and 2015. Primary tumours and lymph nodes were assessed separately. DWI was analysed qualitatively and quantitatively. 18F-FDG-PET/CT was evaluated using the Hopkins criteria. Dichotomous qualitative analysis was carried out for both modalities. Cox regression analysis was used for univariate analysis of recurrence-free survival (RFS). Significant univariate parameters were included in multivariate analysis. In 12 patients, locoregional recurrence occurred. With all imaging strategies, either single-modality or multi-modality, a high negative predictive value (NPV) was achieved (94.3-100%). In response evaluation of the primary site, the preferred strategy is 18F-FDG-PET/CT only, which resulted in a sensitivity of 85.7%, specificity of 86.5%, positive predictive value (PPV) of 37.5% and NPV of 98.5%. For response evaluation of the neck, the best results were obtained with a sequential approach only including the second modality in positive reads of the first modality. It did not matter which modality was assessed first. This strategy for lymph node assessment resulted in a sensitivity, specificity, PPV and NPV of 83.3%, 95.6%, 62.5%, and 98.5%, respectively. After correction for received treatment and human papillomavirus status, primary tumour (P = 0.009) or lymph node (P < 0.001) Hopkins score ≥4 on 18F-FDG-PET/CT remained significant predictors of RFS. For response evaluation of the primary tumour 18F-FDG-PET/CT only is the preferred strategy, whereas for the neck a sequential approach including both DWI and 18F-FDG-PET/CT resulted in the best diagnostic accuracy for follow-up after (chemo)radiotherapy. Qualitative analysis of 18F-FDG-PET/CT is a stronger predictor of RFS than DWI analysis.

Noij DP ，Martens RM ，Koopman T ，Hoekstra OS ，Comans EFI ，Zwezerijnen B ，de Bree R ，de Graaf P ，Castelijns JA ... -  《-》

Correlation between fluorodeoxyglucose hotspots on pretreatment positron emission tomography/CT and preferential sites of local relapse after chemoradiotherapy for head and neck squamous cell carcinoma.

The potential benefits of 18 F-fluoro-2-deoxy-D-glucose-positron emission tomography/CT (FDG-PET/CT) imaging for radiotherapy (RT) treatment planning of head and neck squamous cell carcinoma (HNSCC) are increasingly being recognized. It has been suggested that intratumoral subvolumes with high FDG avidity ("hotspots") are potential targets for selected dose escalation. The purposes of this study were to demonstrate that pre-RT FDG-PET/CT can identify intratumoral sites at increased risk of local relapse after RT and to determine an optimal threshold to delineate smaller RT target volumes that would facilitate RT dose escalation without impaired tolerance. Seventy-two consecutive patients with locally advanced HNSCC treated by RT ± chemotherapy were included in this study. All patients underwent FDG-PET/CT at initial staging (PETA ) and during systematic follow-up (PETR ). FDG-PET/CT was coregistered on the initial CT scan with a rigid method. Various subvolumes (AX ; × = 30%, 40%, 50%, 60%, 70%, 80%, and 90% standardized uptake value maximum [SUVmax] thresholds) within the primary tumor and in the subsequent local relapse (RX ; × = 40% and 70% SUVmax thresholds) were compared together (Dice, Jaccard, overlap fraction, common volume/baseline volume, and common volume/recurrent volume). Nineteen patients (26%) had local relapses. Using a 40% SUVmax threshold, the initial metabolic tumor volume was significantly higher in patients with local relapses than in controlled patients (10.4 ± 8.6 vs 5.1 ± 4.9 cc; p = .002) as well as total lesion glycolysis (117.9 ± 88.6 vs 60.6 ± 80.4; p = .013). For both methods, the overlap index among A30 , A40 , and A50 subvolumes on PETA and the whole metabolic volume of recurrence R40 and R70 on PETR showed a moderate agreement (0.52 to 0.43). Our study does not find high overlap index values between the initial tumor and recurrence subvolumes, probably because of a suboptimal coregistration. Our results also confirm that metabolic tumor volume and total lesion glycolysis are independently correlated with recurrence-free survival in patients with HNSCC. Further larger prospective studies with FDG-PET/CT performed in the same RT position and with a validated elastic registration method are needed. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1155-1165, 2017.

Chaput A ，Calais J ，Robin P ，Thureau S ，Bourhis D ，Modzelewski R ，Schick U ，Vera P ，Salaün PY ，Abgral R ... -  《-》

Neck dissection can be avoided after sequential chemoradiotherapy and negative post-treatment positron emission tomography-computed tomography in N2 head and neck squamous cell carcinoma.

This study assessed neck control in patients with N2 head and neck squamous cell carcinoma (HNSCC) treated with sequential chemoradiotherapy (SCRT) and the incidence of neck recurrence when neck dissection was withheld in those with negative post-treatment fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET). Thirty-four consecutive patients with N2 HNSCC who were treated with radical intent using SCRT were included. Twenty-seven patients received concomitant platinum-based chemotherapy with their radiotherapy. Nineteen patients were treated with intensity-modulated radiotherapy. PET-computed tomography (PET-CT) was obtained 3 months after the completion of radical radiotherapy. Neck dissection was carried out only in those with increased FDG uptake in the neck. The median follow-up was 39.1 months. One patient had increased FDG uptake in the neck post-treatment, which was false positive for malignancy. The remaining 33 patients were observed without neck dissection. No regional recurrence occurred. The negative predictive value (NPV) of post-treatment PET-CT was 100%. Good disease control in the neck can be achieved in patients with N2 HNSCC with SCRT. Post-treatment PET-CT has a high NPV. Neck dissection can be avoided if post-treatment PET-CT is negative.

Loo SW ，Geropantas K ，Beadsmoore C ，Montgomery PQ ，Martin WM ，Roques TW ... -  《-》

Evaluation of 18F-FDG PET/CT and CT/MRI with histopathologic correlation in patients undergoing salvage surgery for head and neck squamous cell carcinoma.

Kim SY ，Kim JS ，Yi JS ，Lee JH ，Choi SH ，Nam SY ，Cho KJ ，Lee SW ，Kim SB ，Roh JL ... -  《-》