A multiparametric approach to predict triple-negative breast cancer including parameters derived from ultrafast dynamic contrast-enhanced MRI.

OBJECTIVE: Triple-negative breast cancer (TNBC) is a highly proliferative breast cancer subtype. We aimed to identify TNBC among invasive cancers presenting as masses using maximum slope (MS) and time to enhancement (TTE) measured on ultrafast (UF) DCE-MRI, ADC measured on DWI, and rim enhancement on UF DCE-MRI and early-phase DCE-MRI. METHODS: This retrospective single-center study, between December 2015 and May 2020, included patients with breast cancer presenting as masses. Early-phase DCE-MRI was performed immediately after UF DCE-MRI. Interrater agreements were evaluated using the intraclass correlation coefficient (ICC) and Cohen's kappa. Univariate and multivariate logistic regression analyses of the MRI parameters, lesion size, and patient age were performed to predict TNBC and create a prediction model. The programmed death-ligand 1 (PD-L1) expression statuses of the patients with TNBCs were also evaluated. RESULTS: In total, 187 women (mean age, 58 years ± 12.9 [standard deviation]) with 191 lesions (33 TNBCs) were evaluated. The ICC for MS, TTE, ADC, and lesion size were 0.95, 0.97, 0.83, and 0.99, respectively. The kappa values of rim enhancements on UF and early-phase DCE-MRI were 0.88 and 0.84, respectively. MS on UF DCE-MRI and rim enhancement on early-phase DCE-MRI remained significant parameters after multivariate analyses. The prediction model created using these significant parameters yielded an area under the curve of 0.74 (95% CI, 0.65, 0.84). The PD-L1-expressing TNBCs tended to have higher rim enhancement rates than the non-PD-L1-expressing TNBCs. CONCLUSION: A multiparametric model using UF and early-phase DCE-MRI parameters may be a potential imaging biomarker to identify TNBCs. CLINICAL RELEVANCE STATEMENT: Prediction of TNBC or non-TNBC at an early point of diagnosis is crucial for appropriate management. This study offers the potential of UF and early-phase DCE-MRI to offer a solution to this clinical issue. KEY POINTS: • It is crucial to predict TNBC at an early clinical period. • Parameters on UF DCE-MRI and early-phase conventional DCE-MRI help in predicting TNBC. • Prediction of TNBC by MRI may be useful in determining appropriate clinical management.

Quantitative analysis from ultrafast dynamic contrast-enhanced breast MRI using population-based versus individual arterial input functions, and comparison with semi-quantitative analysis.

PURPOSE: To evaluate the value of inline quantitative analysis of ultrafast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using a population-based arterial input function (P-AIF) compared with offline quantitative analysis with an individual AIF (I-AIF) and semi-quantitative analysis for diagnosing breast cancer. METHODS: This prospective study included 99 consecutive patients with 109 lesions (85 malignant and 24 benign). Model-based parameters (Ktrans, kep, and ve) and model-free parameters (washin and washout) were derived from CAIPIRINHA-Dixon-TWIST-VIBE (CDTV) DCE-MRI. Univariate analysis and multivariate logistic regression analysis with forward stepwise covariate selection were performed to identify significant variables. The AUC and F1 score were assessed for semi-quantitative and two quantitative analyses. RESULTS: kep from inline quantitative analysis with P-AIF for diagnosing breast cancer provided an AUC similar to kep from offline quantitative analysis with I-AIF (0.782 vs 0.779, p = 0.954), higher compared to washin from semi-quantitative analysis (0.782 vs 0.630, p = 0.034). Furthermore, the inline quantitative analysis with P-AIF achieved the larger F1 score (0.920) compared with offline quantitative analysis with I-AIF (0.780) and semi-quantitative analysis (0.480). There were no statistically significant differences for kep values between the two quantitative analysis schemes (p = 0.944). CONCLUSION: The inline quantitative analysis with P-AIF from CDTV in characterizing breast lesions could offer similar diagnostic accuracy to offline quantitative analysis with I-AIF, and higher diagnostic accuracy to semi-quantitative analysis.

Extracellular volume fraction of the pancreas predicts glucose intolerance in patients undergoing major pancreatic surgeries.

PURPOSE: Pancreatic T1 value and extracellular volume fraction (ECV) are potential imaging biomarkers for pancreatic exocrine and endocrine function. This study aims to evaluate the ability of native T1 value and ECV of the pancreas in predicting postoperative new-onset diabetes (NODM) and worsened glucose tolerance in patients undergoing major pancreatic surgeries. METHODS: This retrospective study involved 73 patients who underwent 3 T pancreatic MRI with pre- and postcontrast T1 mapping before major pancreatic surgeries. Patients were divided into non-diabetic, pre-diabetic and diabetic groups based on their glycated hemoglobin (HbA1c) value. Preoperative native T1 value and ECV of the pancreas were compared among the three groups. The correlation of pancreatic T1 value and ECV with HbA1c was assessed by linear regression analysis, and the ability of pancreatic T1 value and ECV for predicting postoperative NODM and worsened glucose tolerance was assessed using Cox Proportional hazards regression analysis. RESULTS: Native pancreatic T1 value and ECV were both significantly higher in diabetic patients compared to pre-diabetic/non-diabetic patients, and ECV was also significantly higher in pre-diabetic patients compared to non-diabetic patients (all p < 0.05). Both native pancreatic T1 value and ECV showed positive correlation with preoperative HbA1c value (r = 0.50 and 0.55, respectively, both p < 0.001). ECV > 30.7% was the only independent predictor for NODM (HR = 5.687, 95% CI: 1.557, 13.468, p = 0.012) and worsened glucose tolerance (HR = 6.783, 95% CI:, 1.753, 15.842, p = 0.010) after surgery. CONCLUSIONS: Pancreatic ECV predicts the risk of postoperative NODM and worsened glucose tolerance in patients undergoing major pancreatic surgeries.

Native T1 mapping for differentiating the histopathologic type, grade, and stage of rectal adenocarcinoma: a pilot study.

BACKGROUND: Previous studies have indicated that T1 relaxation time could be utilized for the analysis of tissue characteristics. T1 mapping technology has been gradually used on research of body tumor. In this study, the application of native T1 relaxation time for differentiating the histopathologic type, grade, and stage of rectal adenocarcinoma was investigated. METHODS: One hundred and twenty patients with pathologically confirmed rectal adenocarcinoma were retrospectively evaluated. All patients underwent high-resolution anatomical magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and T1 mapping sequences. Parameters of T1 relaxation time and apparent diffusion coefficient (ADC) were measured between the different groups. The diagnostic power was evaluated though the receiver operating characteristic (ROC) curve. RESULTS: The T1 and ADC values varied significantly between rectal mucinous adenocarcinoma (MC) and non-mucinous rectal adenocarcinoma (AC) ([1986.1 ± 163.3 ms] vs. [1562.3 ± 244.2 ms] and [1.38 ± 0.23 × 10-3mm2/s] vs. [1.03 ± 0.15 × 10-3mm2/s], respectively; P < 0.001). In the AC group, T1 relaxation time were significantly different between the low- and high-grade adenocarcinoma cases ([1508.7 ± 188.6 ms] vs. [1806.5 ± 317.5 ms], P < 0.001), while no differences were apparent in the ADC values ([1.03 ± 0.14 × 10-3mm2/s] vs. [1.04 ± 0.18 × 10-3mm2/s], P > 0.05). No significant differences in T1 and ADC values were identified between the different T and N stage groups for both MC and AC (all P > 0.05). CONCLUSIONS: Native T1 relaxation time can be used to discriminate MC from AC. The T1 relaxation time was helpful for differentiating the low- and high-grade of AC.

Extracellular volume fraction with MRI: As an alternative predictive biomarker to dynamic contrast-enhanced MRI for chemotherapy response of pancreatic ductal adenocarcinoma.

PURPOSE: To assess the feasibility of extracellular volume (ECV) fraction determined with equilibrium contrast-enhanced MRI for prediction of treatment response to chemotherapy in pancreatic ductal adenocarcinoma (PDAC) in comparison with dynamic contrast-enhanced MRI (DCE-MRI), and to clarify the association between ECV fraction and DCE-MRI-derived pharmacokinetic parameters. METHODS: This retrospective study included 58 consecutive patients with histologically confirmed PDAC who underwent DCE-MRI before systemic chemotherapy. Tumor pharmacokinetic parameters, including the volume transfer coefficient (Ktrans), rate constant (kep), and extracellular extravascular volume fraction (ve) of DCE-MRI, and ECV fraction determined with equilibrium contrast-enhanced MRI were compared between the response and non-response groups. The correlation of tumor ECV fraction with each DCE-MRI-derived pharmacokinetic parameter was examined using Spearman's rank correlation coefficient. RESULTS: Tumor Ktrans, ve, and ECV fraction were significantly higher in the response group than in the non-response group (all, P < 0.001), whereas no significant difference was found in kep (P = 0.119). Tumor ECV fraction showed the highest area under receiver operating characteristic curve of 0.918, with a sensitivity of 89.3%, specificity of 90.0%, and accuracy of 89.7% (cut off, >37.6%). The ECV fraction showed a significant positive correlation with Ktrans (Spearman's coefficient = 0.66, P < 0.001) and ve (Spearman's coefficient = 0.79, P < 0.001). CONCLUSIONS: ECV fraction determined with equilibrium contrast-enhanced MRI was as useful as DCE-MRI-derived pharmacokinetic parameters for predicting treatment response to chemotherapy in patients with PDAC.

A prospective analysis of the diagnostic accuracy of 3 T MRI, CT and endoscopic ultrasound for preoperative T staging of potentially resectable esophageal cancer.

BACKGROUND: Patients with esophageal cancer (EC) undergo endoscopic ultrasound and CT based cancer staging. Recent technical developments allow improved MRI quality with diminished motion artifact that may allow MRI to compare favorable to CT for noninvasive staging. Hence the purpose of the study was to assess image quality and diagnostic accuracy of 3 T MRI versus CT and EUS for preoperative T-staging of potentially resectable esophageal cancer. METHODS: Between October-2014 and December-2017, esophageal cancer patients with T-staging by EUS were enrolled in this prospective study. Post-operative histopathologic T-staging was the reference standard. All participants underwent MRI [T2- multi-shot turbo spin echo sequence (msTSE), diffusion-weighted imaging (DWI), and 3D gradient-echo based sequence (3D-GRE)] and CT [non-contrast and multiphase contrast-enhanced CT scanning] 5.6 + 3.6 days after endoscopy. Surgery was performed within 3.6 + 3.5 days after imaging. Two blinded endoscopists (reader 1 and 2) and radiologists (reader 3 and 4) independently evaluated EUS and CT/MRI, respectively. Considering the clinical relevance, patients were dichotomized into early (T1 and T2) vs late (T3 and T4) stage cancer before assessment. For statistical purpose, the binary decision was defined as the ability of the imaging technique to diagnose early stage/not early stage esophageal cancer. Diagnostic performance of EUS, MRI and CT was compared using McNemar's test with Bonferroni correction; kappa values were assessed for reader performance. RESULTS: 74 study participants (60 ± 8 yrs.; 56 men) with esophageal cancer were evaluated, of whom 85%(63/74) had squamous cell carcinoma, 61%(45/74) were at early stage and 39%(29/74) were at late stage cancer, as determined by histopathology. Intra- and Inter-reader agreement for pre-operative vs post-operative T-staging was excellent for all imaging modalities. Compared to CT, MRI showed significantly higher accuracy for both the readers (reader3: 96% vs 82%, p = 0.0038, reader4: 95% vs 80%, p = 0.0076, for MRI vs CT, respectively). Further, MRI outperformed EUS with higher specificity (reader 1 vs 3: 59% vs 93%, p = 0.0015, reader 2 vs 4: 66% vs 93%, p = 0.0081, for EUS vs MRI respectively), and accuracy (reader 1 vs 3: 81% vs 96%, p = 0.0022, reader 2 vs 4: 85% vs 95%, p = 0.057, for EUS vs MRI, respectively). CONCLUSION: For resectable esophageal cancer, MRI had better diagnostic performance for tumor staging compared to CT and EUS. TRIAL REGISTRATION: ChiCTR, ChiCTR-DOD, Registered 2nd October 2014, http://www.chictr.org.cn/showproj.aspx?proj=9620.

Arterial Phase with CAIPIRINHA-Dixon-TWIST (CDT)-Volume-Interpolated Breath-Hold Examination (VIBE) in Detecting Hepatic Metastases.

PURPOSE: To evaluate lesion enhancement performance of Multi-Arterial CAIPIRINHA-Dixon-TWIST-Volume-Interpolated Breath-Hold Examination (MA-CDT-VIBE) for the detection of hepatic metastases. MATERIALS AND METHODS: Thirty-one patients with suspicious hepatic metastases were enrolled in this retrospective study. Two independent radiologists scored visualization of each lesion on a scale of 1 (poor visualization) to 11 (excellent visualization) on 11 sets of images. These included 6 hepatic arterial sub-phases acquired in one breath-hold, 1 series of the mean of 6 hepatic arterial sub-phases, 3 subtracted arterial sub-phases, and 1 portal venous phase. The phases with good (score 8-10) and excellent (score 11) lesion visualization were identified, and the number of lesions seen on each of these phases was compared to the number of lesions that was seen best on the equivalent-to-conventional single arterial phase as well as to those that were see best on the mean of 6 hepatic arterial sub-phases. Inter-reader agreement was also calculated. RESULTS: The MA-CDT-VIBE was successfully acquired in 25 patients with hypervascular metastases (96 lesions) and 6 patients with hypovascular metastases (13 lesions). In case of hypervascular metastases, the 6th/6 arterial sub-phase had excellent lesion visualization (sore of 11) in 56 and 44 lesions for the 2 readers, respectively. Good lesion visualization (score of 8-10) was recorded in 5th/6 arterial subphases, in 81 and 67 lesions for the 2 readers, respectively. In case of hypovascular metastases, the portal venous phase had excellent lesion visualization (sore of 11) in all 13 lesions for the 2 readers. Good lesion visualization (score of 8-10) was recorded in 12 and 13 lesions on the 5th/6 and 6th/6 arterial subphases, respectively. More hypervascular lesions scored good (score of 8-10) and excellent (score of 11) on the 5th/6 and 6th/6 phases of MA-CDT-VIBE compared with the equivalent-to-conventional single arterial phase (3rd/6) and the set with mean of 6 hepatic arterial sub-phases. The results were statistically significant (t test, P<.0001). Inter-reader agreement was good for hypervascular lesions (kappa=0.627, P<.0001) and excellent for hypovascular lesions (kappa=1.0, P<.0001), respectively. CONCLUSIONS: The MA-CDT-VIBE improves lesion conspicuity by providing a wide observation window for hypervascular lesions. For hypovascular lesions, the advantage of multiple arterial sub-phases over the portal venous phase is not apparent.

Improved Detection of Recurrent Hepatocellular Carcinomas in Arterial Phase With CAIPIRINHA-Dixon-TWIST-Volumetric Interpolated Breath-Hold Examination.

PURPOSE: The aim of this study was to assess the detection rate of recurrent hepatocellular carcinoma (HCC) in arterial phase using multiarterial CAIPIRINHA-Dixon-TWIST-VIBE (MA-CDT-VIBE). MATERIALS AND METHODS: Fifty-eight patients with possible recurrence of HCC were retrospectively included in this cohort. Patients were scanned with a prototype dynamic contrast-enhanced breath-hold CDT-VIBE sequence, which included 6 arterial subphases with a temporal resolution of 2.64 seconds on a 3 T scanner. Absence and presence of recurrence was documented by consensus of 2 experienced radiologists using magnetic resonance imaging multiphase imaging and follow-up evaluation. The third of 6 arterial subphases was considered the equivalent-to-conventional single arterial phase from the contrast bolus timing perspective. The detection rate of recurrent HCCs in arterial phase by another 2 independent experienced readers was compared for all 6 arterial subphases of MA-CDT-VIBE and the equivalent-to-conventional single arterial phase. Interreader agreement was also calculated. RESULTS: Of the 55 patients reviewed, 46 patients (201 lesions) had recurrent HCC and 9 patients had no recurrence. There was an excellent interreader agreement for both MA-CDT-VIBE (κ = 1.000, P < 0.0001) and the equivalent-to-conventional single arterial phase (κ = 0.850, P < 0.0001). MA-CDT-VIBE showed the detection rate of 100% for all lesions with the diameter of less than 1 cm, 1 to 2 cm, and more than 2 cm. The equivalent-to-conventional single arterial phase resulted in the detection rate of 81.1% and 83.1% for all recurrent HCCs by the 2 readers, respectively, with 78.7% and 83.6% for lesions measuring less than 1 cm, 79.2% and 81.2% for lesions measuring 1 to 2 cm, and 89.7% and 87.2% for lesions measuring more than 2 cm. CONCLUSIONS: Compared with the equivalent-to-conventional single arterial phase, MA-CDT-VIBE with 6 arterial subphases demonstrated higher detection rate of recurrent HCCs in arterial phase and provided a wider arterial observation window, especially for recurrent HCCs less than 2 cm in diameter.