Lijing Zhu

Apparent diffusion coefficient histogram analysis can evaluate radiation-induced parotid damage and predict late xerostomia degree in nasopharyngeal carcinoma

We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased (P < 0.001, = 0.001, and < 0.001, respectively), but all other ADC histogram parameters increased (all P < 0.001, except P = 0.006 for standard deviation [SD]). From time point 2 to 3, parotid volume continued to decrease (P = 0.022), and SD, 75th and 90th percentiles continued to increase (P = 0.024, 0.010, and 0.006, respectively). Early change rates of parotid ADCmean, ADCmin, kurtosis, and 25th, 50th, 75th, 90th percentiles (from time point 1 to 2) correlated with late parotid atrophy rate (from time point 1 to 3) (all P < 0.05). Multiple linear regression analysis revealed correlations among parotid volume, time point, and ADC histogram parameters. Early mean change rates for bilateral parotid SD and ADCmax could predict late xerostomia degrees at seven months after radiotherapy (three months after time point 3) with AUC of 0.781 and 0.818 (P = 0.014, 0.005, respectively). ADC histogram parameters were reproducible (intraclass correlation coefficient, 0.830 - 0.999). ADC histogram analysis could be used to evaluate radiation-induced parotid damage noninvasively, and predict late xerostomia degrees of NPC patients treated with radiotherapy.

Three-dimensional power Doppler ultrasound in the early assessment of response to concurrent chemo-radiotherapy for advanced cervical cancer

Background Three-dimensional power Doppler ultrasound (3D-PDU) imaging has been widely applied to the differentiation of benign and malignant cervical lesions; however, its potential value for predicting response to chemo-radiotherapy has not been fully explored. Purpose To investigate the feasibility of 3D-PDU imaging in predicting treatment response in patients receiving concurrent chemo-radiotherapy (CCRT) for advanced cervical cancer. Material and Methods Fifty-two patients with advanced cervical cancer who received CCRT underwent 3D-PDU examinations at four timepoints: pre-therapy (baseline), 1 week and 2 weeks during, as well as immediately post CCRT. Final tumor response was determined by change in tumor size using magnetic resonance imaging (MRI). Cervical tumor volumes and vascular indices were calculated and compared with the clinical outcome. Results Of the 52 patients, 32 patients who completed all four examinations were included in the analyses: 21 were classified as complete response (CR) and 11 as partial response (PR). During the treatment, the CR group showed that 3D vascular indices (VI and VFI) significantly increased at 1 week (P = 0.028, P = 0.017, respectively) then decreased at 2 weeks and obviously decreased at therapy completion (both P < 0.001), whereas tumors significantly decreased in volume at 2 weeks after therapy initiation (P < 0.05). However, no significant differences in 3D vascular indices values were seen in the PR group during the treatment course (all P > 0.05). Conclusion Prospective longitudinal 3D-PDU imaging may have potentials in monitoring early therapeutic response to CCRT in patients with cervical cancer.

Histogram analysis of apparent diffusion coefficient for monitoring early response in patients with advanced cervical cancers undergoing concurrent chemo-radiotherapy

Background Apparent diffusion coefficient (ADC) histogram analysis has been widely used in determining tumor prognosis. Purpose To investigate the dynamic changes of ADC histogram parameters during concurrent chemo-radiotherapy (CCRT) in patients with advanced cervical cancers. Material and Methods This prospective study enrolled 32 patients with advanced cervical cancers undergoing CCRT who received diffusion-weighted (DW) magnetic resonance imaging (MRI) before CCRT, at the end of the second and fourth week during CCRT and one month after CCRT completion. The ADC histogram for the entire tumor volume was generated, and a series of histogram parameters was obtained. Dynamic changes of those parameters in cervical cancers were investigated as early biomarkers for treatment response. Results All histogram parameters except AUClow showed significant changes during CCRT (all P < 0.05). There were three variable trends involving different parameters. The mode, 5th, 10th, and 25th percentiles showed similar early increase rates (33.33%, 33.99%, 34.12%, and 30.49%, respectively) at the end of the second week of CCRT. The pre-CCRT 5th and 25th percentiles of the complete response (CR) group were significantly lower than those of the partial response (PR) group. Conclusion A series of ADC histogram parameters of cervical cancers changed significantly at the early stage of CCRT, indicating their potential in monitoring early tumor response to therapy.

Whole-lesion ADC histogram and texture analysis in predicting recurrence of cervical cancer treated with CCRT

Purpose To explore the value of whole-lesion apparent diffusion coefficient (ADC) histogram and texture analysis in predicting tumor recurrence of advanced cervical cancer treated with concurrent chemo-radiotherapy (CCRT). Methods 36 women with pathologically confirmed advanced cervical squamous carcinomas were enrolled in this prospective study. 3.0 T pelvic MR examinations including diffusion weighted imaging (b = 0, 800 s/mm2) were performed before CCRT (pre-CCRT) and at the end of 2nd week of CCRT (mid-CCRT). ADC histogram and texture features were derived from the whole volume of cervical cancers. Results With a mean follow-up of 25 months (range, 11 ∼ 43), 10/36 (27.8%) patients ended with recurrence. Pre-CCRT 75th, 90th, correlation, autocorrelation and mid-CCRT ADCmean, 10th, 25th, 50th, 75th, 90th, autocorrelation can effectively differentiate the recurrence from nonrecurrence group with area under the curve ranging from 0.742 to 0.850 (P values range, 0.001 ∼ 0.038). Conclusions Pre- and mid-treatment whole-lesion ADC histogram and texture analysis hold great potential in predicting tumor recurrence of advanced cervical cancer treated with CCRT.

Texture Analysis as Imaging Biomarker for recurrence in advanced cervical cancer treated with CCRT

This prospective study explored the application of texture features extracted from T2WI and apparent diffusion coefficient (ADC) maps in predicting recurrence of advanced cervical cancer patients treated with concurrent chemoradiotherapy (CCRT). We included 34 patients with advanced cervical cancer who underwent pelvic MR imaging before, during and after CCRT. Radiomic feature extraction was performed by using software at T2WI and ADC maps. The performance of texture parameters in predicting recurrence was evaluated. After a median follow-up of 31 months, eleven patients (32.4%) had recurrence. At four weeks after CCRT initiated, the most textural parameters (four T2 textural parameters and two ADC textural parameters) showed significant difference between the recurrence and nonrecurrence group (P values range, 0.002~0.046). Among them, RunLengthNonuniformity (RLN) from T2 and energy from ADC maps were the best selected predictors and together yield an AUC of 0.885. The support vector machine (SVM) classifier using ADC textural parameters performed best in predicting recurrence, while combining T2 textural parameters may add little value in prognosis. T2 and ADC textural parameters have potential as non-invasive imaging biomarkers in early predicting recurrence in advanced cervical cancer treated with CCRT.

Ultrasonic histogram assessment of early response to concurrent chemo-radiotherapy in patients with locally advanced cervical cancer: a feasibility study

PURPOSE To monitor early response for locally advanced cervical cancers undergoing concurrent chemo-radiotherapy (CCRT) by ultrasonic histogram. METHODS B-mode ultrasound examinations were performed at 4 time points in thirty-four patients during CCRT. Six ultrasonic histogram parameters were used to assess the echogenicity, homogeneity and heterogeneity of tumors. RESULTS Ipeak increased rapidly since the first week after therapy initiation, whereas Wlow, Whigh and Ahigh changed significantly at the second week. The average ultrasonic histogram progressively moved toward the right and converted into more symmetrical shape. CONCLUSION Ultrasonic histogram could be served as a potential marker to monitor early response during CCRT.

Predictive and prognostic value of intravoxel incoherent motion (IVIM) MR imaging in patients with advanced cervical cancers undergoing concurrent chemo-radiotherapy

By using the intravoxel incoherent motion (IVIM) model, the diffusion-related coefficient (D) and the perfusion-related parameter (f) can be obtained simultaneously. Here, we explored the application of IVIM MR imaging in predicting long-term prognosis in patients with advanced cervical cancers treated with concurrent chemo-radiotherapy (CCRT). In this study, pelvic MR examinations including an IVIM sequence were performed on 30 women with advanced cervical cancers at three time points (within 2 weeks before, as well as 2 and 4 weeks after, the initiation of CCRT). The performance of tumour size and IVIM-derived parameters in predicting long-term prognosis was evaluated. After a median follow-up of 24 months (range, 10∼34 months), 25/30 (83.33%) patients were alive, and 21/30 (70.00%) remained free of disease. A shrinkage rate of maximum diameter (time point 1 vs. 3) ≥ 58.31% was useful in predicting a good long-term prognosis. The IVIM-derived apparent diffusion coefficient (ADCIVIM) value at time point 2 and the ADCIVIM and f values at time point 3 also performed well in predicting a good prognosis, with AUC of 0.767, 0.857 and 0.820, respectively. IVIM MR imaging has great potential in predicting long-term prognosis in patients with advanced cervical cancers treated with CCRT.

Predicting and Early Monitoring Treatment Efficiency of Cervical Cancer Under Concurrent Chemoradiotherapy by Intravoxel Incoherent Motion Magnetic Resonance Imaging

Objective The aim of this study was to explore the potential of intravoxel incoherent motion magnetic resonance (MR) imaging in predicting and measuring responses to concurrent chemoradiotherapy (CCRT) in advanced cervical cancers. Methods Thirty-seven patients with advanced cervical cancers scheduled for CCRT underwent MR examinations including intravoxel incoherent motion sequence with 9 b values (0–800 s/mm2) before CCRT, 2 and 4 weeks after the initiation of CCRT, and immediately after CCRT. Apparent diffusion coefficient, f, D, and D* values were obtained during the course. The maximum diameter of the tumor was measured to determine the treatment efficiency. Results At the end of CCRT, 25 patients were classified as complete response and 12 as partial response. The pretreatment f of cervical cancer showed its efficiency in predicting partial response and complete response with an area under receiver operating characteristic curve of 0.768. During CCRT, the apparent diffusion coefficient, D, and D* values kept on rising, whereas f increased first and then decreased after 4 weeks of CCRT. Conclusions Intravoxel incoherent motion MR imaging held great potential in both predicting and early monitoring treatment efficiency of advanced cervical cancer under CCRT.

Early Changes of Irradiated Parotid Glands Evaluated by T1rho-Weighted Imaging: A Pilot Study.

Objective The aim of the study was to confirm the feasibility of T1rho-weighted imaging to evaluate the dynamic changes of parotid glands in patients with nasopharyngeal carcinoma (NPC) undergoing intensity-modulated radiation therapy. Methods Twenty-six NPC patients (19 men; 7 women; mean [SD] age, 48.9 [13.4] years) underwent the following 3 serial T1rho-weighted imaging: within 2 weeks before radiotherapy (RT, pre-RT), 5 weeks after the beginning of RT (mid-RT), and 4 weeks after RT (post-RT). Parotid volumes, T1rho values, mean radiation doses, and xerostomia degrees were recorded. Change rates of parotid T1rho values were correlated with parotid atrophy rates, mean radiation doses, and xerostomia degrees. Results During RT, parotid volume decreased (atrophy rate, 32.7 [8.1%] at mid-RT and 27.9 [10.0%] at post-RT compared with pre-RT; both P < 0.001) and parotid T1rho values increased (change rate, 25.0 [15.8%] at mid-RT and 30.1 [18.0%] at post-RT compared with pre-RT, both P < 0.001) significantly. The change rate of parotid T1rho value correlated with the atrophy rate significantly at post-RT (r = 0.301, P = 0.047). Intraobserver and interobserver reproducibility of parotid T1rho measurements were excellent (intraclass correlation coefficient, 0.974 and 0.956, respectively). Conclusions Dynamic changes of radiation-induced parotid damage in NPC patients who underwent intensity-modulated radiation therapy could be noninvasively evaluated by T1rho-weighted imaging.