Exploring the developing preterm brain with diffusion tensor magnetic resonance imaging

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Early MRI Predictors of Relapse in Primary Central Nervous System Lymphoma Treated with MATRix Immunochemotherapy

Primary Central Nervous System Lymphoma (PCNSL) is a highly malignant brain tumour. We investigated dynamic changes in tumour volume and apparent diffusion coefficient (ADC) measurements for predicting outcome following treatment with MATRix chemotherapy in PCNSL. Patients treated with MATRix (n = 38) underwent T1 contrast-enhanced (T1CE) and diffusion-weighted imaging (DWI) before treatment, after two cycles and after four cycles of chemotherapy. Response was assessed using the International PCNSL Collaborative Group (IPCG) imaging criteria. ADC histogram parameters and T1CE tumour volumes were compared among response groups, using one-way ANOVA testing. Logistic regression was performed to examine those imaging parameters predictive of response. Response after two cycles of chemotherapy differed from response after four cycles; of the six patients with progressive disease (PD) after four cycles of treatment, two (33%) had demonstrated a partial response (PR) or complete response (CR) after two cycles. ADCmean at baseline, T1CE at baseline and T1CE percentage volume change differed between response groups (0.005 < p < 0.038) and were predictive of MATRix treatment response (area under the curve: 0.672–0.854). Baseline ADC and T1CE metrics are potential biomarkers for risk stratification of PCNSL patients early during remission induction therapy with MATRix. Standard interim response assessment (after two cycles) according to IPCG imaging criteria does not reliably predict early disease progression in the context of a conventional treatment approach

Apparent diffusion coefficient agreement and reliability using different region of interest methods for the evaluation of head and neck cancer post chemo-radiotherapy

OBJECTIVES: Post chemoradiotherapy (CRT) interval changes in apparent diffusion coefficient (ADC) have prognostic value in head and neck squamous cell cancer (HNSCC). The impact of using different region of interest (ROI) methods on interobserver agreement and their ability to reliably detect the changes in the ADC values was assessed. METHODS: Following ethical approval, 25 patients (mean age 59.5 years, 21 male) with stage 3–4 HNSCC undergoing CRT were recruited for this prospective cohort study. Diffusion weighted MRI (DW-MRI) was performed pre-treatment and at 6 and 12 weeks following CRT. Two radiologists independently delineated ROIs using whole volume (ROI(v)), largest area (ROI(a)) or representative area (ROI(r)) methods at primary tumour (n = 22) and largest nodal (n = 24) locations and recorded the ADC(mean). When no clear focus of increased DWI signal was evident at follow-up, a standardised ROI was placed (non-measurable or NM). Bland-Altman plots and interclass correlation coefficient (ICC) were assessed. Paired t-tests evaluated interval changes in pre- and post-treatment ADC(mean) at each location, which were compared to the smallest detectable difference (SDD). RESULTS: Excellent agreement was obtained for all ROI methods at pre-treatment (ICC 0.94–0.98) and 6-week post-treatment (ICC 0.94–0.98). At 12-week post-treatment, agreement was excellent (ICC 0.91–0.94) apart from ROI(r) (ICC 0.86) and the NM nodal disease (ICC 0.87). There were significant interval increases in ADC(mean) between pre-treatment and post-treatment studies, which were greater than the SDD for all ROIs. CONCLUSIONS: ADC(mean) values can be reproducibly obtained in HNSCC using the different ROI techniques on pre- and post-CRT MRI, and this reliably detects the interval changes

Correlations between DW-MRI and 18F-FDG PET/CT parameters in head and neck squamous cell carcinoma following definitive chemo-radiotherapy.

Abstract Background Posttreatment diffusion–weighted magnetic resonance imaging (DW‐MRI) and 18F‐fluorodeoxygluocose (18F‐FDG) positron emission tomography (PET) with computed tomography (PET/CT) have potential prognostic value following chemo‐radiotherapy (CRT) for head and neck squamous cell carcinoma (HNSCC). Correlations between these PET/CT (standardized uptake value or SUV) and DW‐MRI (apparent diffusion coefficient or ADC) parameters have only been previously explored in the pretreatment setting. Aim To evaluate stage III and IV HNSCC at 12‐weeks post‐CRT for the correlation between SUVmax and ADC values and their interval changes from pretreatment imaging. Methods Fifty‐six patients (45 male, 11 female, mean age 59.9 + − 7.38) with stage 3 and 4 HNSCC patients underwent 12‐week posttreatment DW‐MRI and 18F‐FDG PET/CT studies in this prospective study. There were 41/56 patients in the cohort with human papilloma virus‐related oropharyngeal cancer (HPV OPC). DW‐MRI (ADCmax and ADCmin) and 18F‐FDG PET/CT (SUVmax and SUVmax ratio to liver) parameters were measured at the site of primary tumors (n = 48) and the largest lymph nodes (n = 52). Kendall's tau evaluated the correlation between DW‐MRI and 18F‐FDG PET/CT parameters. Mann‐Whitney test compared the post‐CRT PET/CT and DW‐MRI parameters between those participants with and without 2‐year disease‐free survival (DFS). Results There was no correlation between DW‐MRI and 18F‐FDG PET/CT parameters on 12‐week posttreatment imaging (P = .455‐.794; tau = −0.075‐0.25) or their interval changes from pretreatment to 12‐week posttreatment imaging (P = .1‐.946; tau = −0.194‐0.044). The primary tumor ADCmean (P = .03) and the interval change in nodal ADCmin (P = .05) predicted 2‐year DFS but none of the 18F‐FDG PET/CT parameters were associated with 2‐year DFS. Conclusions There is no correlation between the quantitative DWI‐MRI and 18F‐FDG PET/CT parameters derived from 12‐week post‐CRT studies. These parameters may be independent biomarkers however in this HPV OPC dominant cohort, only selected ADC parameters demonstrated prognostic significance. Study was prospectively registered at http://www.controlled-trials.com/ISRCTN5832708

The impact of human papilloma virus status on the prediction of head and neck cancer chemoradiotherapy outcomes using the pre-treatment apparent diffusion coefficient

OBJECTIVE: To determine the impact of Human Papilloma Virus (HPV) oropharyngeal cancer (OPC) status on the prediction of head and neck squamous cell cancer (HNSCC) chemoradiotherapy (CRT) outcomes with pre-treatment quantitative diffusion-weighted magnetic resonance imaging (DW-MRI). METHODS: Following ethical approval, 65 participants (53 male, age 59.9 ± 7.86) underwent pre-treatment DW-MRI in this prospective cohort observational study. There were 46 HPV OPC and 19 other HNSCC cases with Stage III/IV HNSCC. Regions of interest (ROIs) (volume, largest area, core) at the primary tumour (n = 57) and largest pathological node (n = 59) were placed to analyse ADC(mean) and ADC(min). Unpaired t-test or Mann–Whitney test evaluated the impact of HPV OPC status and clinical parameters on their prediction of post-CRT 2 year locoregional and disease-free survival (LRFS and DFS). Multivariate logistic regression compared significant variables with 2 year outcomes. RESULTS: On univariate analysis of all participants, the primary tumour area ADC(mean) was predictive of 2 year LRFS (p = 0.04). However, only the HPV OPC diagnosis (LFRS p = 0.03; DFS p = 0.02) predicted outcomes on multivariate analysis. None of the pre-treatment ADC values were predictive of 2 year DFS in the HPV OPC subgroup (p = 0.21–0.68). Amongst participants without 2 year disease-free survival, HPV-OPC was found to have much lower primary tumour ADC(mean) values than other HNSCC. CONCLUSION: Knowledge of HPV OPC status is required in order to determine the impact of the pre-treatment ADC values on post-CRT outcomes in HNSCC. ADVANCES IN KNOWLEDGE: Pre-treatment ADC(mean) and ADC(min) values acquired using different ROI methods are not predictive of 2 year survival outcomes in HPV OPC