Assessment of the extracellular volume fraction for the grading of clear cell renal cell carcinoma: first results and histopathological findings

Zhu

et al. 2020

Quant Imaging Med Surg

Background: This study aimed to identify clear cell renal cell carcinoma (ccRCC) histopathological grade and differentiate it from fat-poor angiomyolipoma (AML). This was achieved through contrastenhanced magnetic resonance (MR) T1 mapping with intravenous low-dose gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA).Methods: In total, 56 consecutive patients received MR scanning between January 2016 and December 2018 using the pre-and post-contrast-enhanced T1 mapping sequences with low-dose Gd-DTPA (0.036 mmol/kg). RCCs were pathologically proven in 40 patients after surgery and graded according to the International Society of Urological Pathology (ISUP) classification system. Ten AMLs were pathologically proven by surgery histopathology and six AMLs were diagnosed by magnetic resonance imaging (MRI).Patients were followed up for more than half a year. The mean T1 values of the renal lesion and ipsilateral normal renal parenchyma were measured before and after Gd-DTPA administration (T1p and T1e). The reduction of T1 value (T1d) and the ratio of its reduction (T1d %) were calculated and compared.Results: In 40 ccRCCs, higher-grade [International Society of Urologic Pathology (ISUP) grade 3 and 4] and lower-grade (ISUP grade 1 and 2) ccRCCs were noted in 13 and 27 patients, respectively. The mean T1p was 1,514.8±139.4 ms and the mean T1d was 907.7±193.7 ms in the higher-grade ccRCCs, which were significantly higher than in the lower-grade ccRCCs (T1p =1,251.7±151.5 ms and T1d =648.5±218.2 ms, respectively; P<0.001). Fat-poor AMLs had higher T1p (1,677.3±104.8 ms) and T1e (865.6±251.5 ms) as compared to ccRCCs (P<0.001). Combined T1p + T1d showed the highest area under the curve (AUC) (0.912) in the differentiation of higher-grade ccRCCs from lower-grade ccRCCs (P=0.010). Combined T1p + T1e had the highest AUC (0.956) in the differentiation between ccRCCs and fat-poor AMLs (P=0.010).All T1 mapping metrics could discriminate between normal renal parenchyma and renal lesions (P<0.001).No significant difference was found in the T1p and T1e at different parts of the ipsilateral normal renal parenchyma. Interobserver agreement for quantitative longitudinal relaxation time in the T1 maps was excellent.Conclusions: Contrast-enhanced T1 mapping with low-dose Gd-DTPA may provide a more reliable and accurate approach in identifying ccRCCs histopathological grade and differentiating ccRCCs from fat-poor AMLs.

Section: Discussionmentioning

confidence: 99%

Contrast-enhanced magnetic resonance (MR) T1 mapping with low-dose gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) is promising in identifying clear cell renal cell carcinoma histopathological grade and differentiating fat-poor angiomyolipoma

Zhu

et al. 2020

Quant Imaging Med Surg

“…The DECT-derived ECV fraction has been validated for the evaluation of cardiac [21] and hepatic [22] brosis. A previous study [23] demonstrated an increase in the ECV fraction in various tumors, particularly higher grades of clear cell renal cell carcinoma, indicating the role of the extracellular matrix in modulating tumor growth, proliferation, and invasion. In our study, we found that the ECV fraction was signi cantly higher in the malignant breast lesions than in the benign lesions and in the invasive carcinoma than in the DCIS, as well as in the hormone receptor-negative and Ki67-positive groups.…”

Section: Discussionmentioning

confidence: 82%

Extracellular volume fraction derived from routine chest dual-energy CT for the characterization of breast tumor: Comparison with apparent diffusion coefficient and validation against histopathological findings

Cao

et al. 2022

Preprint

Background: Tumor aggressiveness and therapeutic response are influenced not only by cancer cells but also by the extracellular matrix in tumor microenvironment, which can be quantified by extracellular volume (ECV) fraction derived from dual-energy CT (DECT). We aimed to investigate the feasibility of using routine chest DECT-derived ECV fraction for the characterization of breast tumor, compared to apparent diffusion coefficient (ADC) and validated against histopathological findings.Methods: The ECV fraction and ADC value were retrospectively assessed in patients with breast tumor using routine chest DECT and breast MRI, respectively. The diagnostic performance in predicting the histopathological characteristics [benign vs. malignant, invasive carcinoma vs. ductal carcinoma in situ (DCIS)], immunohistochemical biomarker status and pathological complete response (pCR) status. Histopathological sections (H&E staining) were analyzed to assess histopathological ECV by digital image analysis. Pearson’s correlation analysis was used to correlate between DECT-derived ECV and histopathological ECV fractions.Results: This study included 271 patients, with 314 breast lesions (61 benign and 253 malignant). The ECV fraction and ADC value showed comparable area under the curve (AUC) for distinguishing benign from malignant lesions (0.777 and 0.822, p = 0.123) and invasive carcinoma from DCIS (0.640 and 0.727, p = 0.115). There were significant differences in ECV fraction between different hormone receptor and Ki67 states (p = 0.001 ~ 0.014), while ADC values only differed among various Ki67 states (p < 0.001). The ECV fraction was lower (p = 0.007), while the ADC value was higher (p = 0.013) in the pCR than in the non-pCR group, with an AUC value of 0.748 and 0.730 (p = 0.887), respectively. There was a positive correlation between DECT-derived ECV and histopathological ECV fractions (r = 0.615, p < 0.01).Conclusions: Routine chest DECT-derived ECV fraction is a viable quantitative imaging biomarker for the characterization of breast tumor.

“…The ECV is the sum of extravascular-extracellular space and intravascular space, and it has been demonstrated for the evaluation of liver and myocardial fibrosis 24,25 and amyloid deposition 26,27 that higher ECV is associated with more severe fibrosis and amyloid deposition, respectively. Some recent studies have also used ECV fractions for oncology evaluation, including the identification of the histological grade of renal clear cell carcinoma, 21 histologic classification of thymic epithelial tumors, 22 and evaluation of the response and survival prediction of pancreatic tumors after chemotherapy. 23,28 Most results showed that the higher the malignant potential of tumor, the higher the ECV fraction.…”

Section: Discussionmentioning

confidence: 99%

“…The extracellular volume (ECV) fraction, representing the proportion of extracellular space, is calculated by the ratio of changes in T1 values of lesions and arteries at the same level before and after contrast injection on a T1 mapping sequence. 21 The ECV fraction has been increasingly used in oncological imaging as a valuable imaging marker to predict tumor grade, postchemotherapy response, and survival of cancer patients over the recent years. [21][22][23] However, the clinical value of T1 mapping-based ECV in preoperative differentiation of LVSI in cervical cancer remains unclear.…”

mentioning

confidence: 99%

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PreliminaryMRIStudy of Extracellular Volume Fraction for Identification of Lymphovascular Space Invasion of Cervical Cancer

Magnetic Resonance Imaging

Fan

Yang

et al. 2022

Background: Lymphovascular space invasion (LVSI) is a risk factor for poor prognosis of cervical cancer. Preoperative identification of LVSI is very difficult.Purpose: To evaluate the potential of extracellular volume (ECV) fraction based on T1 mapping in preoperative identification of LVSI in cervical cancer compared with dynamic contrast-enhanced MRI (DCE-MRI). Study Type: Retrospective. Subjects: A total of 79 patients (median age 54 years) with cervical cancer were classified into LVSI group (n = 29) and without LVSI group (n = 50) according to postoperative pathology. Field Strength/Sequence: A 3-T, noncontrast and contrast-enhanced T1 mapping performed with volume interpolated breath hold examination (VIBE) sequence, DCE-MRI applied with 3D T1-weighted VIBE sequence. Assessment: Regions of interest along the medial edge of the lesion were drawn on slices depicting the maximum crosssection of the tumor. The noncontrast and contrast-enhanced T1 value of the tumor and arteries in the same slice were measured, and ECV was calculated from T1 values. The parametric maps (K trans , k ep , and v e ) derived from DCE-MRI standard Toft's model were evaluated. Statistical Tests: ECV, K trans , k ep , and v e between groups with and without LVSI were compared using Student's t-test. The receiver operating characteristic (ROC) curve and DeLong test were used to evaluate and compare the diagnostic performance of ECV, K trans , k ep , and v e for differentiating LVSI. P < 0.05 was considered statistically significant. Results: The ECV and K trans of the LVSI group were significantly higher than that of non-LVSI group (52.86% vs. 36.77%, 0.239 vs. 0.176, respectively), and no significant differences in K ep or v e values were observed (P = 0.071 and P = 0.168, respectively). The ECV fraction showed significantly higher area under ROC curve than K trans for differentiating LVSI (0.874 vs. 0.655, respectively). Data Conclusion: ECV measurements based on T1 mapping might improve the discrimination between patients with and without LVSI in cervical cancer, showing better performance for this purpose than DCE-MRI.