Cervical spine osteoradionecrosis or bone metastasis after radiotherapy for nasopharyngeal carcinoma? The MRI-based radiomics for characterization.

BACKGROUND: To develop and validate an MRI-based radiomics nomogram for differentiation of cervical spine ORN from metastasis after radiotherapy (RT) in nasopharyngeal carcinoma (NPC). METHODS: A radiomics nomogram was developed in a training set that comprised 46 NPC patients after RT with 95 cervical spine lesions (ORN, n = 51; metastasis, n = 44), and data were gathered from January 2008 to December 2012. 279 radiomics features were extracted from the axial contrast-enhanced T1-weighted image (CE-T1WI). A radiomics signature was created by using the least absolute shrinkage and selection operator (LASSO) algorithm. A nomogram model was developed based on the radiomics scores. The performance of the nomogram was determined in terms of its discrimination, calibration, and clinical utility. An independent validation set contained 25 consecutive patients with 47 lesions (ORN, n = 25; metastasis, n = 22) from January 2013 to December 2015. RESULTS: The radiomics signature that comprised eight selected features was significantly associated with the differentiation of cervical spine ORN and metastasis. The nomogram model demonstrated good calibration and discrimination in the training set [AUC, 0.725; 95% confidence interval (CI), 0.622-0.828] and the validation set (AUC, 0.720; 95% CI, 0.573-0.867). The decision curve analysis indicated that the radiomics nomogram was clinically useful. CONCLUSIONS: MRI-based radiomics nomogram shows potential value to differentiate cervical spine ORN from metastasis after RT in NPC.

Cardiovascular Risk Stratification by Automatic Coronary Artery Calcium Scoring on Pretreatment Chest Computed Tomography in Diffuse Large B-Cell Lymphoma Receiving Anthracycline-Based Chemotherapy: A Multicenter Study.

BACKGROUND: Balancing the cardiovascular risk and benefit of anthracycline-based chemotherapy in patients with diffuse large B-cell lymphoma is an important clinical issue. We aimed to evaluate whether the pretreatment coronary artery calcium score (CACS) can stratify the risk of cancer therapy-related cardiac dysfunction (CTRCD) and major adverse cardiovascular events (MACEs) in patients with diffuse large B-cell lymphoma receiving anthracycline-based chemotherapy. METHODS: The patients with diffuse large B-cell lymphoma from 4 hospitals were retrospectively enrolled. The CACS was automatically calculated on nongated chest computed tomography before treatment using artificial intelligence-CACS software and divided into 3 categories (0, 1-100, and >100). The associations between the CACS and CTRCD and between the CACS and MACEs were assessed by logistic regression and Fine-Gray competing-risk regression model. Nelson-Aalen cumulative risk curve was performed to assess the cumulative incidence of MACEs. RESULTS: A total of 1468 patients (785 men and 683 women; 100% Asian) were enrolled, and 362 and 185 patients developed CTRCD and MACEs, respectively. Compared with a CACS of 0 (n=826), there was stepwise higher odds of CTRCD with a CACS between 1 and 100 (n=356; odds ratio, 2.587) and a CACS >100 (n=286; odds ratio, 5.239). The CACS was associated with MACEs (1-100 versus 0: subdistribution hazard ratio 3.726; >100 versus 0: subdistribution hazard ratio 7.858; all P<0.001). Competing risk-adjusted MACEs rates for patients with a CACS of 0, 1 to 100, and >100 were 1.21%, 8.43%, and 11.19%, respectively, at 3 years, and 3.27%, 16.01%, 31.12%, respectively, at 5 years. CONCLUSIONS: The automatic CACS derived from chest computed tomography before treatment was helpful to identify high-risk patients of CTRCD and MACE and guide clinicians to implement cardiovascular protection strategies in patients with diffuse large B-cell lymphoma who received anthracycline-based chemotherapy.

Reproducibility and usefulness of quantitative apparent diffusion coefficient measurements for predicting program death-ligand 1 expression in nasopharyngeal carcinoma.

BACKGROUND: Accurate assessment of programmed death-ligand 1 (PD-L1) expression status in nasopharyngeal carcinoma (NPC) before immunotherapy is crucial. We aimed to explore the reproducibility and usefulness of the quantitative apparent diffusion coefficient (ADC) measurements for predicting PD-L1expression status in NPC. METHODS: We retrospectively recruited 134 NPC patients who underwent MRI scans and PD-L1 detection. A PD-L1 combined positive score (CPS) ≥ 20 was identified as high expression status. Patients were divide into two cohorts based on the MRI scanning devices, including a 1.5-T MRI cohort (n = 85, 44 PD-L1 high expression) and a 3.0-T MRI cohort (n = 49, 24 PD-L1 high expression). The mean ADC (ADCmean), minimum ADC (ADCmin) and maximal ADC (ADCmax) values were independently measured by two observers. The ADC measurement reproducibility was assessed by interclass correlation coefficients (ICC). The correlations between ADC parameters and CPS were analyzed by spearman's correlation coefficient (r), and the performance for PD-L1expression status prediction was assessed by the area under receiver operating characteristic curve (AUC). RESULTS: The measurement reproducibility of ADCmean, ADCmin and ADCmax was good in the 1.5-T MRI cohort (ICC: 0.843-0.930) and 3.0-T MRI cohort (ICC: 0.929-0.960). The ADCmean, ADCmin, and ADCmax tended to inversely correlate with the CPS (r:-0.37 - -0.52 in the 1.5-T MRI cohort, and - 0.52 - -0.60 in the 3.0-T MRI cohort; P all < 0.01). The ADCmean, ADCmin and ADCmax yielded the AUC of 0.756 (95% CI: 0.651, 0.861), 0.689 (95% CI: 0.576, 0.802), and 0.733 (95%CI: 0.626, 0.839) in the 1.5-T MRI cohort and 0.820 (95%CI: 0.703, 0.937), 0.755 (95% CI: 0.616, 0.894), and 0.760 (95%CI: 0.627, 0.893) in the 3.0-T MRI cohort for predicting PD-L1 high expression status, respectively. CONCLUSION: ADC measurements may act as a reproducible and feasible method to predict PD-L1 expression status in NPC.

MRI-based radiomics to compare the survival benefit of induction chemotherapy plus concurrent chemoradiotherapy versus concurrent chemoradiotherapy plus adjuvant chemotherapy in locoregionally advanced nasopharyngeal carcinoma: A multicenter study.

BACKGROUND AND PURPOSE: It remains uncertain whether induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) or CCRT plus adjuvant chemotherapy (AC) is more effective in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). This study aimed to develop and validate a joint radiomic and clinical signature (RCS) for the prognostic stratification of LA-NPCs and to identify patients who might benefit more from IC + CCRT or CCRT + AC. MATERIALS AND METHODS: Overall, 893 LA-NPC patients who received IC + CCRT or CCRT + AC were enrolled from four hospitals. RCS based on pretreatment magnetic resonance images and clinical data was constructed for predicting 5-year progression-free survival (PFS). The predictive ability of the RCS and TNM staging system for 5-year PFS, locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were compared by Harrell's concordance indices (C-indices). Patients were divided into high- and low-risk subgroups based on RCS scores. The survival benefit of IC + CCRT vs. CCRT + AC in different subgroups was compared by Kaplan-Meier survival curves. RESULTS: The RCS combining the radiomic signature, TNM stage and EBV DNA demonstrated significantly higher C-indices than TNM stage for predicting 5-year PFS, LRRFS, DMFS and OS in the training and validation cohorts. In the high-risk group (RCS score ≥ 0.25), CCRT + AC achieved significantly better PFS, LRRFS, DMFS and OS than IC + CCRT. In the low-risk group (RCS score < 0.25), IC + CCRT yielded significantly better outcomes than CCRT + AC. CONCLUSION: The RCS provides a noninvasive way to predict the outcomes of LA-NPC and helps identify patients who may benefit more from IC + CCRT vs. CCRT + AC.

Characterization of Insufficiency Fracture and Bone Metastasis After Radiotherapy in Patients With Cervical Cancer Detected by Bone Scan: Role of Magnetic Resonance Imaging.

Background: Insufficiency fracture (IF) can show increased uptake on a bone scan (BS). IFs are often misinterpreted as bone metastases if the characteristic "Honda sign" (H-sign) is invisible. The purpose of the present study was to evaluate the utility of magnetic resonance imaging (MRI) alone for the characterization of IF and bone metastasis after radiotherapy in patients with cervical cancer detected by BS. Materials and Methods: Our study included 40 patients with cervical cancer after radiotherapy that showed pelvic emerging increased uptake on a BS during follow-up. Then further MRI examination was performed in all patients. Two radiologists independently reviewed the MR images, and the sensitivity, specificity and accuracy were calculated based on the mean scores. Diagnostic validity of the inter-observer was calculated by using kappa statistics. The gold standard was based on radiologic findings, clinical data and follow-up at least 12 months. Results: A total of 57 emerging bone lesions detected at BS were identified in the reference standard, including 43 IFs and 14 bone metastases. Only 20 patients showed a "H-sign" on the BS images. Using MRI analysis, all lesions detected by BS were found in MRI by both radiologists. On average, the sensitivity, specificity, and accuracy for distinguishing IFs from bone metastases were 95.3% (41/43), 92.8% (13/14), and 94.7% (54/57), respectively. The inter-observer variability was determined to be very good (kappa value = 0.962). Conclusions: MRI is a reliable diagnostic technique for the further characterization of emerging lesions detected by BS, MRI shows great diagnostic efficiency in the differentiation of IF and bone metastasis.