Application of Dynamic Enhanced Magnetic Resonance Imaging Texture Analysis Combined with ADCs in Predicting Pelvic Lymph Metastasis of Prostate Cancer

OBJECTIVE

The application value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) texture analysis combined with apparent diffusion coefficient (ADC) in predicting pelvic lymph node metastasis of prostate cancer was explored.

METHODS

The clinical and imaging data of 151 patients with prostate cancer admitted to The Affiliated Tumor Hospital of Guizhou Medical University from November 2019 to November 2021 were retrospectively analysed. According to the final pathological diagnosis results, they were divided into two groups: Metastasis group (n = 63, pelvic lymph node metastasis) and non-metastasis group (n = 88, no pelvic lymph node metastasis). The DCE-MRI texture parameters and ADCs of the two groups were compared using Omni-Kinetics software and MADC software packages. The receiver operating characteristic (ROC) curve was used in evaluating the predictive value of each method and their combination, and Spearman rank correlation analysis was used in evaluating their correlation.

RESULTS

The volume transfer (Ktrans) and interstitium-to-plasmarate rate constant (Kep) in the metastatic group were significantly higher than those in the non-metastatic group (p < 0.001). However, no significant difference in extravascular extracellular space volume fraction (Ve) was found between the groups (p > 0.05). The ADC of the metastatic group was lower (p < 0.001). The Ktrans and Kep values were positively correlated with pelvic lymph node metastasis of prostate cancer (r = 0.580, 0.684; p < 0.001), and the ADC was negatively correlated with pelvic lymph node metastasis of prostate cancer (r = -0.478; p < 0.001). The ROC curve showed that the area under the curve (AUC) of DCE-MRI texture analysis parameters Ktrans and Kep combined with ADC was large, and the prediction efficiency increased. The AUC, sensitivity and specificity were 0.974, 95.20% and 93.20% (p < 0.001), respectively.

CONCLUSIONS

DCE-MRI texture analysis combined with ADC value can accurately predict pelvic lymphatic metastasis of prostate cancer, which is helpful for the selection and formulation of clinical treatment plans and has certain guiding value for the implementation of pelvic lymph node clearing in patients.

The value of dynamic contrast-enhanced magnetic resonance imaging combined with apparent diffusion coefficient in the differentiation of benign and malignant diseases of the breast

BACKGROUND

The value of combined dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and apparent diffusion coefficient (ADC) histogram analysis for the diagnosis of breast cancer has not been evaluated in previous studies.

PURPOSE

To investigate the diagnostic value of DCE-MRI combined with ADC in benign and malignant breast lesions.

MATERIAL AND METHODS

The clinicopathological imaging data included 168 patients (177 lesions) with breast lesions who underwent convention breast MRI, DCE-MRI, and diffusion-weighted imaging (DWI); they were divided into the benign lesion group (n = 39) and malignant lesion group (n = 129) based on pathology.

RESULTS

Using the type III outflow curve as a diagnostic criterion for malignant breast lesions, the diagnostic sensitivity was 76.9%, the specificity was 80%, the correct rate was 72.2%, and its area under the curve (AUC) was 0.823. Using an enhancement ratio > 100% as a diagnostic criterion for malignant breast lesions, the sensitivity was 61.5%, specificity was 80%, and AUC was 0.723. Using > 3 ipsilateral vessels as a diagnostic criterion for malignant lesions in the breast resulted in a diagnostic sensitivity of 81.6%, a specificity of 80.8%, and an AUC of 0.805.

CONCLUSION

The type of time intensity curve DCE-MRI, the early enhancement rate in the first phase, the number of ipsilateral vessels, and the ADC full volume histogram of the blood supply score and DWI are valuable in the diagnosis of benign and malignant breast lesions.

Differential diagnostic value of 64-slice spiral computed tomography in solitary pulmonary nodule

The present study aimed to evaluate the diagnostic value of 64-slice spiral multivariate computed tomography (CT) combined with dynamic contrast-enhanced scanning for benign and malignant solitary pulmonary nodules (SPNs). A total of 93 patients with SPN as diagnosed by CT were included. All these patients were subjected to routine and dynamic enhancement CT scanning. After reconstruction, the morphological characteristics following dynamic enhancement were analyzed, and compared for the benign and malignant SPN cases. The incidences of lobulation, spicular sign, pleural indentation and vacuole sign in the malignant SPN group were significantly higher compared with the benign SPN group. During the dynamic enhancement scanning, the CT values at all the time points for the inflammatory and malignant SPN groups were significantly higher than the benign SPN group. No significant differences were observed in the dynamic enhancement CT values at 30, 60, 90 and 120 sec between the inflammatory, and malignant SPN groups. However, in the inflammatory SPN group, the dynamic enhancement CT values at 300 and 540 sec were significantly lower than the malignant SPN group. Notably, the diagnostic accordance rate for the morphological signs combined with dynamic enhancement diagnosis was significantly higher than the morphological signs alone. The 64-slice spiral CT morphological signs combined with dynamic enhancement detection can be more effective for the differential diagnosis of benign and malignant SPN, which may provide potent evidence for the early clinical treatment.

ROI for outlining an entire tumor is a reliable approach for quantification of lung cancer tumor vascular parameters using CT perfusion

OBJECTIVE

To investigate the effect of position and size of tumor region of interest (ROI) on the estimation of lung cancer vascular parameters using 256-slice computed tomography (CT) perfusion.

METHODS

After institutional review board approval and written informed consent, 16 men and 11 women with lung cancer were enrolled in this CT perfusion study. Perfusion, blood volume, and peak enhancement were determined for 60 or 120 mm(2) circular ROIs placed at the edge, center, and around (outlining) the visible tumor. Average values were obtained by performing ROI analysis twice by the same observers without any procedural changes.

RESULTS

Perfusion, blood volume, and peak enhancement measurements were substantially higher at the edge than at the center for both 60 and 120 mm(2) ROIs (all P<0.05). Measurements varied substantially depending on the ROI size. Perfusion, blood volume, and peak enhancement for the ROIs outlining tumor were intermediate between those at the tumor edge and center. There were significant correlations between median values and interquartile ranges as follows; perfusion (12.51 [7.91-28.10] mL⋅min(-1)⋅100 mL(-1)), blood volume (29.31 [21.82-37.65] mL⋅100 g(-1)), peak enhancement (12.93 [2.42-22.50]) for the ROIs outlining the tumor, and microvascular density ([19.43±8.78] vessels/0.74 mm(2)), respectively (r values were 0.732, 0.590, and 0.544 respectively, all P<0.05).

CONCLUSION

Spatial and size selection of ROI significantly affects CT perfusion analysis. ROI outlining of entire tumor provides efficient and reliable measurements for clinical assessment of lung cancer using CT perfusion.

Dynamic enhancement pattern of HCC smaller than 3 cm in diameter on gadoxetic acid-enhanced MRI: comparison with multiphasic MDCT

BACKGROUND & AIMS

The dynamic enhancement pattern of HCCs smaller than 3 cm in diameter on gadoxetic acid-enhanced magnetic resonance imaging (MRI) have not been extensively investigated. We aimed to evaluate the dynamic enhancement patterns of small HCCs (≤3 cm) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) and compare enhancement patterns with multiphasic multidetector computed tomography (MDCT) based on tumour cellular differentiation and size.

METHODS

We retrospectively included 55 patients with 67 surgically confirmed small HCCs (≤3 cm) who underwent multiphasic MDCT and gadoxetic acid-enhanced MRI. Dynamic enhancement patterns were analysed according to tumour cellular differentiation and size. Hepatobiliary phase images were also analysed to assess their additional value.

RESULTS

The proportion of small HCCs demonstrating the typical enhancement pattern differed depending on tumour cellular differentiation on both MRI (P = 0.001) and MDCT (P = 0.001), but differed depending on tumour size only on CT (P = 0.008). Gadoxetic acid-enhanced MRI more sensitively depicted the typical enhancement pattern than CT for all tumours (P = 0.001), for moderately or poorly differentiated HCCs (P = 0.021) and for HCCs ≤2 cm (P = 0.001). 80% of tumours with atypical enhancement could be diagnosed as HCC based on tumour size and hepatobiliary phase images.

CONCLUSIONS

On both gadoxetic acid-enhanced MRI and multiphasic CT, the dynamic enhancement patterns of small HCCs (≤3 cm) differed according to tumour cellular differentiation. Gadoxetic acid-enhanced MRI more frequently demonstrated the typical HCC enhancement pattern than CT in small HCCs.

An imaging protocol for dynamic contrast-enhanced breast MRI with 3.0T: using sagittal sequence interleaved between axial sequences

BACKGROUND

B1 transmission-field inhomogeneity has been reported at 3.0 Tesla (T) breast imaging. Enhancement measurements of breast cancers at 3.0T may be insufficient for some patients and improvements in imaging protocols are needed.

PURPOSE

To quantify B1 inhomogeneities in normal tissue and malignant masses at 3.0T breast MR imaging and to evaluate effect of an imaging protocol using an interleaved sagittal sequence in dynamic contrast-enhanced MRI (DCE-MRI).

MATERIAL AND METHODS

A total of 76 patients were included who underwent DCE-MRI of the breast at 3.0T with an imaging protocol consisting of 1st, 2nd, and 4-6th bilateral axial sequences, and 3rd and 7th unilateral sagittal sequences. Signal intensity (SI) of normal breast tissue was measured at nipple level in four bilateral locations (anterior, posterior, medial, and lateral). Mean whole breast and location specific SI were calculated and compared between right and left breast using a paired t-test. All malignant masses were classified into three groups according to tumor size on MRI (≤2 cm, 2-4 cm, >4 cm). SI of malignant masses was measured independently on axial and sagittal sequences. The axial-sagittal SI gap in each mass was calculated and difference between right and left breast was compared using the t test. Size of each malignant mass was compared with pathologic findings to assess performance of the imaging protocol.

RESULTS

SI of normal breast tissue were lower for the right breast (R-L difference, -91.9; P < 0.0001) and in all four locations (anterior, P < 0.01; posterior, P < 0.01; medial, P < 0.0001; lateral, P < 0.0001). SI of malignant masses were lower for the right breast among same size of the lesions (P < 0.0001), particularly < 4 cm (P < 0.0001). Decreased right to left difference in SI was produced with an interleaved sagittal sequence, as axial-sagittal gap of malignant masses was significant when tumor locates on the right side (P < 0.001). The concordance rate in predicting size of mass in this imaging protocol was 92.2%.

CONCLUSION

The interleaved sagittal sequence is helpful to adjust reduced SI of malignant masses on right breast at 3.0T. This imaging protocol is clinically applicable by adding a single sequence during DCE-MRI of the breast.