Pretreatment Apparent Diffusion Coefficient Values Research Articles

Pretreatment diffusion-weighted imaging for prediction of relapsed and refractory primary central nervous system lymphoma.

A subset of primary central nervous system lymphoma (PCNSL) has been shown to undergo an early relapsed/refractory (R/R) period after first-line chemotherapy. This study investigated the pretreatment clinical and MRI features to predict R/R in PCNSL, emphasizing the apparent diffusion coefficient (ADC) values in diffusion-weighted imaging (DWI). This retrospective study investigated the pretreatment MRI features for predicting R/R in PCNSL. Only patients who had undergone complete preoperative and postoperative MRI follow-up studies were included. From January 2006 to December 2021, 52 patients from two medical institutions with a diagnosis of PCNSL were included (median follow-up time, 26.3 months). Among these, 24 (46.2%) had developed R/R (median time to relapse, 13 months). Cox proportional hazard regression analyses were performed to determine hazard ratios for all parameters. Significant predictors of R/R in PCNSL were female sex, complete response (CR) to first-line chemotherapy, and ADC value/ratio (p < 0.05). Cut-off points of ADC values and ADC ratios for prediction of R/R were 0.68 × 10-3 mm2/s and 0.97, with AUCs of 0.78 and 0.77, respectively (p < 0.05). Multivariate Cox proportional hazards analysis showed that failure of CR to first-line chemotherapy and low ADC values (<0.68 × 10-3 mm2/s) were significant risk factors for R/R, with hazard ratios of 5.22 and 14.45, respectively (p < 0.05). Kaplan-Meier analysis showed that lower ADC values and ratios predicted significantly shorter progression-free survival (p < 0.05). Pretreatment ADC values in DWI offer quantitative valuable information for the treatment planning in PCNSL.

Response assessment of locally advanced rectal cancer after neoadjuvant chemoradiotherapy: Is apparent diffusion coefficient useful on 3T magnetic resonance imaging?

To assess the diagnostic value of apparent diffusion coefficient (ADC) on 3T device for the prediction of tumoral response to neoadjuvant chemoradiotherapy (nCRT) and for the response assessment after nCRT in patients with locally advanced rectal cancer (LARC), using pathology as a reference. Forty-one patients affected by LARC undergoing 3.0T MRI before and after nCRT were retrospectively selected. After the conventional acquisition of high resolution T2-weighted sequences, diffusion-weighted MRI (DW-MRI) was performed using a spin-echo echo-planar sequence with multiple b values (150, 500, 1000, 1500 s/mm2 ). Fitted ADC values were calculated for each rectal lesion before and after nCRT by drawing a hand-made region of interest (ROI) around the tumour outline. All patients underwent surgery and pathological staging (classified according to tumour regression grading [TRG] and to tumour and node [TN]) represented the reference standard. Pretreatment ADC value (pre-ADC), ADC value obtained after nCRT (post-ADC) and the difference between post-ADC and pre-ADC (ΔADC) were correlated with both the TRG classes and the TN staging system in each patient. The ADC values obtained in the post nCRT examination and the ΔADC were statistically related both to TRG (p=0.0004; p=0.0126, respectively) and TN (p=0.0484; p=0.0673, respectively) stages at histopathology. On the contrary, the pre-ADC was not related either to the TRG classes or to the lesion TN staging system (p > 0.05). 3 T DW-MRI using ADC value can be useful to assess the efficacy of nCRT in LARC; in fact, post-ADC and ΔADC values improve MR capability to evaluate tumour response.

THE ROLE OF DIFFUSION-WEIGHTED MR IMAGING IN EVALUATING THE RESPONSE TO STEROID THERAPY IN IDIOPATHIC GRANULOMATOUS MASTITIS LESIONS

Objective: The aim of this study was to investigate the role of diffusion-weighted magnetic resonance imaging (DW MRI) with an apparent diffusion coefficient (ADC) map in evaluating the response to treatment of steroid-treated idiopathic granulomatous mastitis (IGM) lesions. Materials and Methods: This retrospective study included 99 lesions of 58 female patients (average age: 32.91 years; range: 22–55 years) with biopsy-proven IGM. Patients were treated with oral and topical steroids. All pre-treatment and post-treatment MR examinations were evaluated. The maximal size of the masses and nonmass enhancement (NME) lesions were measured. Patients were classified as complete response (CR), partial response (PR), and non-response (NR) according to the dynamic contrast-enhanced (DCE) MR findings after treatment. Results: ADC values of areas occupied by IGM (0.933±0.317x10-3 mm2 /sec) were lower than contralateral normal parenchyma (1.259±0.423x10-3 mm2 /sec). Twenty-two (22.22%) of the lesions were in the NR group, 30 (30.30%) in the PR group, and 47 (47.47%) in the CR group. There was no significant difference between the pre-treatment ADC values in NR, PR, and CR groups (p=0.228). There was a significant difference between the pre-treatment and post-treatment ADC values in the PR groups (p=0.001). Conclusion: DW MR imaging in IGM is a useful method to monitor the response to treatment. However, it is not successful in predicting response to treatment.

Feasibility of diffusion-weighted magnetic resonance imaging in evaluation of early therapeutic response after CT-guided microwave ablation of inoperable lung neoplasms

ObjectiveTo determine the early treatment response after microwave ablation (MWA) of inoperable lung neoplasms using the apparent diffusion coefficient (ADC) value calculated 24 h after the ablation.Materials and methodsThis retrospective study included 47 patients with 68 lung lesions, who underwent percutaneous MWA from January 2008 to December 2017. Evaluation of the lesions was done using MRI including DWI sequence with ADC value calculation pre-ablation and 24 h post-ablation. DWI-MR was performed with b values (50, 400, 800 mm2/s). The post-ablation follow-up was performed using chest CT and/or MRI within 24 h following the procedure; after 3, 6, 9, and 12 months; and every 6 months onwards to determine the local tumor response. The post-ablation ADC value changes were compared to the end response of the lesions.ResultsForty-seven patients (mean age: 63.8 ± 14.2 years, 25 women) with 68 lesions having a mean tumor size of 1.5 ± 0.9 cm (range: 0.7–5 cm) were evaluated. Sixty-one lesions (89.7%) showed a complete treatment response, and the remaining 7 lesions (10.3%) showed a local progression (residual activity). There was a statistically significant difference regarding the ADC value measured 24 h after the ablation between the responding (1.7 ± 0.3 × 10−3 mm2/s) and non-responding groups (1.4 ± 0.3 × 10−3 mm2/s) with significantly higher values in the responding group (p = 0.001). A suggested ADC cut-off value of 1.42 could be used as a reference point for the post-ablation response prediction (sensitivity: 66.67%, specificity: 84.21%, PPV: 66.7%, and NPV: 84.2%). No significant difference was reported regarding the ADC value performed before the ablation as a factor for the prognosis of treatment response (p = 0.86).ConclusionADC value assessment following ablation may allow the early prediction of treatment efficacy after MWA of inoperable lung neoplasms.Key Points• ADC value calculated 24 h post-treatment may allow the early prediction of MWA efficacy as a treatment of pulmonary tumors and can be used in the early immediate post-ablation imaging follow-up.• The pre-treatment ADC value of lung neoplasms is not different between the responding and non-responding tumors.

Relevance of diffusion-weighted imaging with background body signal suppression for staging, prognosis, morphology, treatment response, and apparent diffusion coefficient in plasma-cell neoplasms: A single-center, retrospective study.

Accurate staging and evaluation of therapeutic effects are important in managing plasma-cell neoplasms. Diffusion-weighted imaging with body signal suppression magnetic resonance imaging (DWIBS-MRI) allows for acquisition of whole-body volumetric data without radiation exposure. This study aimed to investigate the usefulness of DWIBS-MRI in plasma-cell neoplasms. We retrospectively analyzed 29 and 8 Japanese patients with multiple myeloma and monoclonal gammopathy of undetermined significance, respectively, who underwent DWIBS-MRI. We conducted a histogram analysis of apparent diffusion coefficient values. The correlations between each histogram parameter and staging, cell maturation, prognosis, and treatment response were evaluated. We found that the apparent diffusion coefficient values in patients with monoclonal gammopathy of undetermined significance were lower than those in patients with multiple myeloma. Pretreatment apparent diffusion coefficient values of immature myeloma were lower than those of mature myeloma. Moreover, these values decreased in proportion to stage progression in Durie-Salmon classification system but showed no significant correlation with other staging systems or prognosis. Patients were stratified as responder, stable, and non-responder based on the International Myeloma Working Group criteria. The magnitude of changes in apparent diffusion coefficients differed significantly between responders and non-responders (0.154 ± 0.386 ×10–3 mm2/s vs. -0.307 ± 0.424 ×10–3 mm2/s, p = 0.003). Although its usefulness has yet to be established, DWIBS-MRI combined with apparent diffusion coefficient measurement allowed for excellent response evaluation in patients with multiple myeloma. Furthermore, apparent diffusion coefficient analysis using DWIBS-MRI may be useful in predicting cell maturation and total tumor volume.

Diffusion Tensor Imaging Features of the Auditory Pathways in Patients With Vestibular Schwannoma After Gamma Knife Radiosurgery.

ObjectiveIn this study, we aimed to investigate whether there is any change in diffusion tensor imaging (DTI) parameters in ipsilateral and contralateral auditory pathways after Gamma Knife radiosurgery (GKR) in patients with vestibular schwannoma (VS) and the relationship between radiosurgery variables.MethodsSixty-six patients were evaluated with MRI and DTI before and after GKR. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured from the bilateral lateral lemniscus (LL), inferior colliculus (IC), medial geniculate body (MGB), and Heschl's gyrus (HG).ResultsThere was no significant difference in ADC and FA values obtained from bilateral LL, IC, and MGB before and after radiosurgery. However, there was a significant difference between pretreatment and post-radiosurgery contralateral HG ADC values. The ADC values obtained from the contralateral HG and IC positively correlated with the duration after radiosurgery. As the duration after radiosurgery increases, the difference between the ADC values obtained from ipsilateral and contralateral HG also increases.ConclusionThe high ADC values in the contralateral HG after radiosurgery may indicate microstructural alterations such as demyelination and axonal loss. Radiation exposure doses to the brainstem and cochlea are the most important factors that can cause microstructural damage to the auditory pathways. When planning radiosurgery, extreme care should be taken to prevent the harmful effects of radiation on the auditory pathways.

Pre-treatment Apparent Diffusion Coefficient Does Not Predict Therapy Response to Radiochemotherapy in Cervical Cancer: A Systematic Review and Meta-analysis.

Magnetic resonance imaging is used for staging purposes in cervical cancer (CC). Diffusion-weighted imaging and the apparent diffusion coefficient (ADC) are associated with tumor microstructure. The present analysis sought to compare pre-treatment ADC values to predict treatment outcome of radiochemotherapy for CC based upon a large patient sample. MEDLINE library and SCOPUS databases were assessed for suitable articles up to May 2020. The primary endpoint was the mean ADC value of CC according to the treatment response to radiochemotherapy. In total, 16 studies were included in the analysis. For the response group, 416 patients were included in the analysis (72.5%) and for the no-response group 158 patients were included (27.5%). The mean ADC value of patients with CC with treatment response was 0.87×10-3 mm2/s (95% confidence interval=0.81-0.94×10-3 mm2/s), and for the patients with no response was 0.92×10-3 mm2/s (95% confidence interval=0.85-0.98×10-3 mm2/s). Pre-treatment ADC values alone cannot be used to reliably predict treatment response to radiochemotherapy in CC.

Pretreatment ADC predicts tumor control after Gamma Knife radiosurgery in solid vestibular schwannomas.

Radiosurgery is a well-established treatment for vestibular schwannomas (VSs), but it is often difficult to identify which tumors will respond to treatment. We sought to determine whether pretreatment or posttreatment tumor apparent diffusion coefficient (ADC) values could predict tumor control in patients undergoing Gamma Knife radiosurgery (GKRS) and whether these values could differentiate between cases of pseudoprogression and cases of true progression in the early posttreatment period. We retrospectively identified patients who underwent GKRS for solid VSs between June 2008 and November 2016 and who had a minimum follow-up of 36 months. Pretreatment and posttreatment minimum, mean, and maximum ADC values were measured for the whole tumor volume and were compared between patients with tumor control and those with tumor progression. In patients with early posttreatment tumor enlargement, ADC values were compared between patients with pseudoprogression and those with true progression. Of the 44 study patients, 34 (77.3%) demonstrated tumor control at final follow-up. Patients with tumor control had higher pretreatment minimum (1.35 vs 1.09; p = 0.008), mean (1.80 vs 1.45; p = 0.004), and maximum (2.41 vs 1.91; p = 0.011) ADC values than patients with tumor progression. ADC values did not differ between patients with pseudoprogression and those with true progression at early posttreatment follow-up. ADC values may be helpful in predicting response to GKRS in patients with solid VSs but cannot predict which tumors will undergo pseudoprogression. Patients with higher pretreatment ADC values may be more likely to demonstrate posttreatment tumor control.

Apparent Diffusion Coefficient Can Predict Response to Chemotherapy of Liver Metastases in Colorectal Cancer

The aim of this meta-analysis was to evaluate the suitability of apparent diffusion coefficient (ADC) as a predictor of response to systemic chemotherapy in patients with metastatic colorectal carcinoma (CRC). MEDLINE library, SCOPUS database, and EMBASE database were screened for relationships between pretreatment ADC values of hepatic CRC metastases and response to systemic chemotherapy. Overall, five eligible studies were identified. The following data were extracted: authors, year of publication, study design, number of patients, mean value ADC and standard-deviation, measure method, b-values, and Tesla-strength. The methodological quality of every study was checked according to the Quality Assessment of Diagnostic Studies-2 instrument. The meta-analysis was undertaken by employing RevMan 5.3 software. DerSimonian and Laird random-effects models with inverse-variance weights were used to account for heterogeneity. Mean ADC values including 95% confidence intervals were calculated. Five studies (n = 114 patients) were included. The pretreatment mean ADC in the responder group was 1.15 × 10-3 mm2/s (1.03, 1.28) and 1.37 × 10-3 mm2/s (1.3, 1.44) in the nonresponder group. An ADC baseline threshold of 1.2 × 10-3 mm2/s, below which no nonresponder was found, can distinguish both groups. The results indicate ADC can serve as a predictor of response to chemotherapy for CRC patients.

Assessment of the percentage of apparent diffusion coefficient value changes as an early indicator of the response of colorectal hepatic metastases to chemotherapy

BackgroundColorectal cancer is considered one of the most common causes of cancer-related deaths worldwide. We aim to evaluate the efficacy of DWI-MRI in predicting response to chemotherapy in this cohort.The study included 30 lesions in 20 biopsy proven-colorectal cancer patients with hepatic metastasis larger than 1 cm. All patients underwent both triphasic CT with intravenous contrast, pre-chemotherapy MRI (axial T2 and DW sequences) which was repeated 21 days following chemotherapy. A follow-up CT was done 2 months later. The response of the lesions was evaluated using the RESCIST criteria. On MRI, the lesions corresponding to the ones chosen on CT were identified and the apparent diffusion coefficient (ADC) values of pre- and post-chemotherapy images were recorded and correlated with the CT results.ResultsIn the study, 17 (56.7%) of the lesions showed response to chemotherapy while 13 (43.3%) were non-responding. There was no significant difference in pretreatment ADC values between responding and non-responding lesions (p = 0.14). The mean percentage increase in ADC values in responding lesions was 42% compared to 18% in non-responding lesions (p < 0.001). Lesions that showed less than 18% increase were all found to be non-responsiveConclusionDWI-MRI has an emerging role in early assessment of early treatment response that can be detected before morphological response for patients with hepatic metastasis from colorectal cancer. Based on our study, the use of 25 % as the cutoff point of percent difference in ADC for detection of non-responding lesions proved to be successful only 21 days after the 1st chemotherapy cycle.

Pretreatment ADC is not a prognostic factor for local recurrences in head and neck squamous cell carcinoma when clinical T-stage is known

ObjectivesPretreatment identification of radio-insensitive head and neck squamous cell carcinomas (HNSCC) would affect treatment modality selection. The apparent diffusion coefficient (ADC) of a tumor could be a predictor of local recurrence. However, little is known about its prognostic value next to known factors such as clinical T-stage. The aim of the present study is to determine the added value of pretreatment ADC to clinical T-stage as a prognostic factor for local recurrence.MethodsThis retrospective cohort study included 217 patients with HNSCC treated with (chemo)radiotherapy between April 2009 and December 2015. All patients underwent diffusion-weighted MRI prior to treatment. Median ADC values of all tumors were obtained using a semi-automatic delineation method. Univariate models containing ADC and T-stage were compared with a multivariable model containing both variables.ResultsFifty-eight patients experienced a local recurrence within 3 years. On average, the ADC value in the group of patients with a recurrence was 1.01 versus 1.00 (10−3 mm2/s) in the group without a recurrence. Univariate analysis showed no significant association between tumor ADC and local recurrence within 3 years after (chemo)radiotherapy (p = 0.09). Cox regression showed that clinical T-stage was an independent predictor of local recurrence and adding ADC to the model did not increase its performance.ConclusionPretreatment ADC has no added value as a prognostic factor for local recurrence to clinical T-stage.Key Points• Pretreatment identification of head and neck squamous cell carcinoma patients who do not benefit from (chemo)radiotherapy could improve personalized cancer care.• The apparent diffusion coefficient (ADC) obtained from diffusion-weighted MRI has been reported to be a prognostic factor for local recurrence.• In this study, ADC has no added value as a prognostic factor compared with clinical T-stage.

DWI of Pancreatic Ductal Adenocarcinoma: A Pilot Study to Estimate the Correlation With Metastatic Disease Potential and Overall Survival.

The purpose of this study is to analyze the relationship between the apparent diffusion coefficient (ADC) of pancreatic ductal adenocarcinoma (PDAC) and the presence or development of metastasis and overall survival (OS). Of 290 consecutive patients with histopathologically proven PDAC from January 2013 to December 2014, staging DWI was performed for 124 patients. Image quality was adequate in 112 studies. Sixty-five patients were treatment naïve, but 17 of the 65 were excluded because of the presence of other associated pancreatic pathologic abnormalities. Data for the remaining 48 patients (24 men and 24 women; median age, 65.5 years; interquartile range, 56-77 years) were obtained during a 4-year follow-up period (mean [± SD], 397 ± 415.1 days). The correlation between ADC and the presence or development of metastasis was assessed using descriptive statistics. OS was determined and mortality analysis was performed using Pearson correlation and Kaplan-Meier curves. Of 48 patients, 10 had metastases at staging MRI, and 12 later developed metastatic disease. Among the latter, the mean time from staging MRI to metastasis was 258 ± 274.1 days. Most (86%) metastases were hepatic (n = 19). During the follow-up period, the remaining 26 patients (54%) never developed metastases. Patients with metastatic disease (n = 22) had significantly lower mean ADCs than did those without metastases (1.27 × 10-3 vs 1.43 × 10-3 mm2/s; p = 0.047). The ADC of PDAC had a positive correlation with survival: patients with PDAC with lower ADCs (< 1.36 × 10-3 mm2/s) had significantly worse 4-year OS rates than did patients with higher ADC values (p = 0.036). Pretreatment ADC values of PDAC may be significantly lower in patients who have or will develop metastatic disease and may correlate with worse OS.

The Value of Diffusion-Weighted Magnetic Resonance Imaging in Predicting the Efficacy of Radiation and Chemotherapy in Cervical Cancer.

BackgroundTo analyze the application value of apparent diffusion coefficient (ADC) and exponent apparent diffusion coefficient (EADC) in evaluating the efficacy of radiation and chemotherapy in cervical cancer using pre- and posttreatment diffusion-weighted magnetic resonance imaging (DW-MRI) scans.Methods52 patients with cervical cancer were administered radiation and chemotherapy. Both MRI and DW-MRI were obtained at different stages. The ADC and EADC values, as well as the maximum tumor diameter, were measured and analyzed.ResultsWe found that the ADC value increased after treatment, and the EADC value decreased. Changes in the calculated ADC occurred earlier than the morphologic changes of the tumors. A negative correlation was detected between reduced rates in the maximum tumor diameter two months after treatment and pretreatment ADC value (r = –0.658, P < 0.05). An ROC curve and nonlinear regression analysis showed that the formula, y = (1525500.122x2 – 4689.962x + 3.482) × 100%, can be used to calculate the percentage of complete remission after treatment according to the pretreatment ADC value.ConclusionOur data suggest that pretreatment ADC and EADC values are predictive of the efficacy of radiation and chemotherapy. Both ADC and EADC values during treatment were instrumental in early monitoring and dynamic observation.

RETRACTED ARTICLE: Pre-treatment DWI as a predictor of overall survival in locally advanced pancreatic cancer treated with Cyberknife radiotherapy and sequential S-1 therapy

BackgroundTo identify the value of the pre-treatment apparent diffusion coefficient (ADC) derived from diffusion weighted imaging (DWI) in predicting the overall survival (OS) for locally advanced pancreatic cancer (LAPC) treated with Cyberknife followed by sequential S-1 chemotherapy.MethodsPatients with UICC-T4 LAPC who underwent DWI scan (3.0 Tesla) using two b-values (0, 600 s/mm2) in our center between 2015 and 2017 were enrolled. Mean ADCs of the region of interest (ROI) drawn manually on DWI imaging were measured by two independent radiologists at an interval of 1 month. The association between prognostic factors and patient survival was determined using univariate and multivariate analyses. Cox proportional hazard model was used for identification of independent prognostic factors of OS.ResultsA total of 41 patients (28 males and 13 females) were included, with a median age of 64 years, with 5 patients (3 males and 2 females) lost. The median OS was 11.7 months (range 2.8–23.3) among all 41 patients. The 1-year OS was 46% (95% CI 30%–62%). Univariate and multivariate analyses indicated that pre-treatment ADC value (HR 10.652, P = 0.0093), age (HR 0.952, P = 0.015), CA19–9 (HR 1.001, P = 0.0022) and administration of S-1 (HR 0.128, P = 0.0002) were independent predicting factors of OS.ConclusionThe mean ADC value of the primary tumor on pre-treatment DWI imaging was an independent predictor of OS in patients with LAPC receiving Cyberknife followed by sequential S-1.

Imaging biomarkers guided anti-angiogenic therapy for malignant gliomas

Antiangiogenic therapy is a universal approach to the treatment of malignant gliomas but fails to prolong the overall survival of newly diagnosed or recurrent glioblastoma patients. Imaging biomarkers are quantitative imaging parameters capable of objectively describing biological processes, pathological changes and treatment responses in some situations and have been utilized for outcome predictions of malignant gliomas in anti-angiogenic therapy. Advanced magnetic resonance imaging techniques (including perfusion-weighted imaging and diffusion-weighted imaging), positron emission computed tomography and magnetic resonance spectroscopy are imaging techniques that can be used to acquire imaging biomarkers, including the relative cerebral blood volume (rCBV), Ktrans, and the apparent diffusion coefficient (ADC). Imaging indicators for a better prognosis when treating malignant gliomas with antiangiogenic therapy include the following: a lower pre- or post-treatment rCBV, less change in rCBV during treatment, a lower pre-treatment Ktrans, a higher vascular normalization index during treatment, less change in arterio-venous overlap during treatment, lower pre-treatment ADC values for the lower peak, smaller ADC volume changes during treatment, and metabolic changes in glucose and phenylalanine. The investigation and utilization of these imaging markers may confront challenges, but may also promote further development of anti-angiogenic therapy. Despite considerable evidence, future prospective studies are critically needed to consolidate the current data and identify novel biomarkers.

Transarterial chemoembolization in pancreatic adenocarcinoma with liver metastases: MR-based tumor response evaluation, apparent diffusion coefficient (ADC) patterns, and survival rates

PurposeTo retrospectively investigate the effectiveness of triple drug combination transarterial chemoembolization (TACE) on local tumor response and survival in patients with liver metastases from pancreatic cancer. Also, this study will evaluate the variances in response regarding the number of metastases, assess the correlation between tumor response and the changes in the apparent diffusion coefficients (ADC) in diffusion weighted (DW) MRI. Materials and methodsOne hundred and twelve patients (58 men and 54 women; mean age 57) with malignant liver metastases from pancreatic adenocarcinoma underwent at least one session of TACE with a chemotherapeutic combination of mitomycin C, cisplatin, and gemcitabine. A size-based evaluation of tumor response (response evaluation criteria in solid tumors (RECIST)) was conducted, along with ADC values, and survival indices as related to treatment pattern. ResultsFour weeks following the end of the treatment, 78.26% of patients showed stable disease and 11.59% showed partial response. The median survival time was 19 months and for the stable disease group, 26 months. Low pretreatment ADC values showed no significant correlation to poor response to treatment (r = 0.347,p = 0.146). ConclusionThe triple drug TACE technique showed improvements in median survival times in patients with hepatic metastases from pancreatic carcinoma and helped control disease progression, whereas the number of hepatic lesions was not a statistically significant factor in patients' response to TACE. The data suggest that pre-treatment ADC values in DW-MRI have no statistical correlation with tumor response.

The prognostic value of pretreatment tumor apparent diffusion coefficient values in nasopharyngeal carcinoma

BackgroundDiffusion-weighted MR imaging (DWI) has increasingly contributed to the management of nasopharyngeal carcinoma (NPC) patients. The objective of this paper was to explore the prognostic significance of apparent diffusion coefficient (ADC) values in 93 NPC patients.MethodsThis retrospective study included 93 newly diagnosed NPC patients. Pretreatment ADC values were determined and compared with patients’ age, gender, alcohol intake, smoking, tumor volume, pathological type, tumor stage, and nodal stage. Using the Kaplan-Meier method, overall survival (OS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were calculated and the values compared between the low and high ADC groups. Multivariate analysis of ADC values and other 9 clinical parameters was performed using a Cox proportional hazards model to test the independent significance for OS, LRFS and DMFS.ResultsThe mean ADC value for the initial nasopharyngeal tumors was 0.72 × 10−3 mm2/s (range: 0.48–0.97 × 10−3 mm2/s). There was no significant difference between pretreatment ADCs and patient’ gender, age, smoking, alcohol intake, or tumor stage. A significant difference in the ADCs for different N stages (P = 0.022) and correlation with initial tumor volume (r = −0.26, P = 0.012) were observed. In comparison, the ADC value for undifferentiated carcinoma was lower than that for other 3 pathological types. With a median follow-up period of 50 months, the 3-year and 5-year OS rates were 88.2% and 83.3%, respectively, 3-year and 5-year LRFS rates were 93.5% and 93.3%, respectively, and 3-year and 5-year DMFS rates were 83.9% and 83.3%, respectively. Patients with tumor ADC values ≥0.72 × 10−3 mm2/s exhibited longer OS and LRFS periods compared with tumor ADC values <0.72 × 10−3 mm2/s, with P values 0.036 and 0.018, respectively. In addition, patients with deaths or recurrences or distant metastasis had significant lower ADC values than those without disease failures. According to a multivariate analysis using the Cox proportional hazard test, ADC values showed a significant correlation with OS (P = 0.0004), LRFS (P = 0.0009), and DMFS (P < 0.0001), respectively.ConclusionsPretreatment tumor ADC values supposed to be a noninvasive important prognostic parameter for NPC.

Analysis of the Relation between Pretreatment ADC Value and Prognosis in Patients Treated With Concurrent Chemoradiation Therapy for Locally Advanced Pancreatic Cancer

The purpose of this study is to investigate the predictive usefulness of the apparent diffusion coefficient (ADC) value in diffusion weighted magnetic resonance imaging before the concurrent chemoradiation (CCRT) for locally advanced pancreatic cancer (LAPC). We retrospectively analyzed 18 LAPC patients who underwent CCRT from February 2009 to December 2014 in our institution and had evaluable diffusion-weighted image. Radiotherapy was given with expiratory breath-hold intensity modulated radiation therapy (IMRT) to a dose of 36-51Gy (median: 43.5Gy) in 15 factions, and gemcitabine 1000mg/m2 was given concurrently. They were 9 males and 9 females, and median age was 65.5 years old (42-83 years old). Sixteen patients had Eastern Cooperative Oncology Group Performance Status (PS) of 0, and the others had PS of 1. Thirteen patients had T4 cancer (Stage III) according to the 7th Union for International Cancer Control staging system and one of them had regional lymph node metastasis, and the others had T3 cancer without metastasis (Stage IIA). The ADC of the tumor was calculated from 2 different b-value diffusion weighted images (0 or 500 and 1,000 s/mm2). The overall survival (OS), local recurrence-free survival (LRFS), and distant disease-free survival (DDFS) was evaluated by Kaplan-Meier analysis. The log-rank test and univariate Cox proportional hazards model was also used to evaluate the association between mean ADC value in whole gross tumor volume (mADCt) and OS, LRFS, and DDFS. With a median follow-up of 16.5 months (range: 10.3-47.0 months), the median survival time (MST), median LRFS, and median DDFS were 16.5 months, 11.6 months, and 10.3 months (range: 10.3-47.0 months, 3.9-47.0 months, and 1.2-34.0 months), respectively. The median mADCt value was 1.37 x10-3 mm2/s (range: 1.06-1.77 x10-3 mm2/s). The mADCt value less than the higher one-third (<1.44 x10-3 mm2/s) was significantly associated with OS (MST 13.8 vs 27.5 months, p=0.015) and LRFS (median 10.7 vs 21.1 months, p=0.005), but was not associated with DDFS (median 9.6 vs 14.3 months, p=0.156) in the log-rank test. In the Cox model, there were significant relation between mADCt and both OS (HR 4.40, 95% CI 1.21-16.0, p=0.024) and LRFS (HR 5.82, 95% CI 1.52-22.3, p=0.010), but mADCt has no significant relation to DDFS (HR 2.13, 95% CI 0.73-6.21, p=0.165), as well. The mADCt before treatment may be useful to predict the OS and LRFS of LAPC patients treated with CCRT.

Early changes in the apparent diffusion coefficient and MMP-9 expression of a cervical carcinoma U14 allograft model following irradiation.

A cervical carcinoma allograft model was designed to assess the correlation between early changes in the apparent diffusion coefficient (ADC) values on diffusion-weighted magnetic resonance imaging (DW-MRI) and the expression of matrix metalloproteinase-9 (MMP-9) in tumors. BALB/c mice with U14 tumor allografts on the right rear flank were irradiated with a single 20 Gy dose. All tumor-bearing mice were subjected to DW-MRI, followed by calculation of the ADC values and characterization of the T1 and T2 relaxation time constants. Pre- and post-irradiation ADC values were compared with the tumor volume, and the immunohistochemical staining of MMP-9 and hematoxylin-eosin (HE) staining of tumor allografts. However, no correlations between the pre-treatment ADC values and changes in tumor volumes following irradiation were observed. Notably, the mean ADC value was significantly higher in the irradiated tumors (0.756±0.102×10-3 mm2/sec) as compared with those in the untreated tumors (0.501±0.052×10-3 mm2/sec; P=0.002; r=0.682). Additionally, immunohistochemical staining demonstrated that MMP-9 expression in the irradiated tumors was significantly increased. The mean ADC value was significantly higher in the irradiated tumors with high MMP-9 expression levels (0.815±0.112×10-3 mm2/sec), as compared with in the untreated tumors with low MMP-9 expression levels (0.631±0.068×10-3 mm2/sec). Quantitative analysis determined that the ADC values were correlated with MMP-9 expression (r=0.752; P=0.003). Combined, these results suggest that radiation-induced increases in MMP-9 expression levels may be responsible for early changes in the mean ADC value and the response to irradiation in cervical carcinoma.

The application value of apparent diffusion coefficient in monitoring the response to chemotherapy of primary bone lymphoma

Objective To investigate the application value of apparent diffusion coefficient (ADC) in monitoring the response to chemotherapy of primary bone lymphoma (PBL) . Methods Sixteen consecutive patients with PBL confirmed by pathology were enrolled in this retrospective study. All patients underwent a controlled MRI including a DWI sequence before chemotherapy and after the first chemotherapy session. The ADC values of PBL lesions were measured before and after the first chemotherapy session. All patients were divided into responders and non-responders groups according to the combined response assessment criteria. The difference in ADC values between the responders and non-responders groups before and after chemotherapy and the rate of change of ADC values were compared using Wilcoxon test. The paired t test was used to compare ADC values before and after chemotherapy in each group. Results Twenty-three cases of PBL lesions were diagnosed in 16 patients before the chemotherapy. After the first chemotherapy session, 10 patients (12 lesions) and 6 patients (11 lesions) were categorized into the responder and non-responder group, respectively. The mean pre-treatment ADC value of the responder group and non-responder group were 737.1 (301.7, 928.4) ×10-6mm2/s and 749.2 (624.4, 1 186.5) ×10-6mm2/s, which had no statistically significant difference (Z=1.51, P=0.132). The mean post-treatment ADC value of the responder group and non-responder group were 1 843.0 (721.5, 2 745.8) ×10-6mm2/s and 1 026.3 (382.8, 2 100.8) ×10-6mm2/s, which had no statistically significant difference (Z=-1.75, P=0.079). The post-treatment ADC value of the responder group significantly increased [156.7 (60.9, 227.5) %] while the post-treatment ADC value of the non-responder group slightly increased [31.7 (-44.7, 147.4) %]. The difference in the percentage changes of ADC values in the responder and non-responder groups before and after the treatment was statistically significant (Z=-3.66, P<0.001) . Conclusion The measurement of the percentage changes of ADC values enable a good short-term response evaluation for PBL. Key words: Bone neoplasms; Lymphoma; Antineoplastic combined chemotherapy protocols; Treatment outcome; Magnetic resonance imaging