[Clinical value of diffusion-weighted magnetic resonance imaging for localization of prostate cancer--comparison with the step sections of radical prostatectomy].

PURPOSE: The objective of our study was to compare T2-weighted magnetic resonance imaging (T2WI), combined T2-weighted and dynamic imaging (Dynamic), and combined T2-weighted and diffusion-weighted imaging (DWI) in the identification of the site of prostate cancer. MATERIALS AND METHODS: Before radical prostatectomy, 85 patients with prostate cancer underwent magnetic resonance imaging using a 1.5-T endorectal coil; we excluded 3 patients treated with neoadjuvant hormonal therapy. The sites of prostate cancer in 82 patients were predicted by T2WI alone, T2WI + Dynamic, and T2WI + DWI, and the results were compared with the step-section analysis of radical prostatectomy specimens. The peripheral zone (PZ) and the transition zone (TZ) of the prostate were divided into left and right halves. Only tumors with a diameter of more than 5 mm were considered significant. RESULTS: The sensitivity, specificity, positive predictive value (PPV), and the area under the receiver operating characteristic (ROC) curve (Az) for the prediction of the site of prostate cancer in the PZ of the prostate were as follows: 42%, 94%, 93%, and 0.76 for T2WI alone; 48%, 96%, 96%, and 0.78 for T2WI + Dynamic; and 50%, 96%, 96%, and 0.81 for T2WI + DWI. The sensitivity, specificity, PPV, and Az for the prediction of the site of prostate cancer in the TZ of the prostate were as follows: 31%, 92%, 76%, and 0.66 for T2WI alone; 46%, 82%, 67%, and 0.65 for T2WI + Dynamic; and 48%, 94%, 85%, and 0.71 for T2WI + DWI. CONCLUSION: The Az value for the prediction of prostate cancer in the PZ and those in the TZ of the prostate was the highest for the combined T2WI and DWI approach.

Hypervascular hepatocellular carcinoma: Combined dynamic MDCT and SPIO-enhanced MRI versus combined CTHA and CTAP.

AIM: Recently, many diagnostic modalities have been developed for the detection of hepatocellular carcinoma (HCC). Of these, a less invasive and more accurate diagnostic procedure is desirable. This study was undertaken to compare combined dynamic multidetector row helical computerized tomography (MDCT) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) with combined CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) for the detection of hypervascular HCC. METHODS: Forty-eight patients with 56 pathologically proved hypervascular HCCs (less than 5.0 cm in diameter) underwent dynamic MDCT and SPIO-enhanced MRI, as well as CTHA and CTAP. The images were reviewed by four independent and blinded readers on a tumor-by-tumor basis. RESULTS: The mean areas under alternative-free response receiver operating characteristic curve (Az) for combined dynamic MDCT and SPIO-enhanced MRI (IV set) and combinedCTHA and CTAP (IA set) were comparable (0.948 and 0.969, respectively, P > 0.05), although the Az value of the IV set was significantly lower than that of the IA set in HCCs smaller than or equal to 1.5 cm (0.867 and 0.937, respectively, P = 0.033). The mean sensitivity and positive predictive value of the IV set were similar to those of the IA set. CONCLUSIONS: Combined dynamic MDCT and SPIO-enhanced MRI showed a diagnostic accuracy comparable to intra-arterial contrast-enhanced CT (CTHA and CTAP) for hypervascular HCC, and may be a useful diagnostic option prior to curative treatments of hypervascular HCC, although a limitation exists in detecting HCCs smaller than or equal to 1.5 cm.

Imaging characteristics of papillary renal cell carcinoma by computed tomography scan and magnetic resonance imaging.

AIM: To analyse the differences in the patterns between clear and papillary renal cell carcinomas using magnetic resonance imaging (MRI) and dual-phase helical computed tomography (CT). METHODS: We examined seven patients with papillary renal cell carcinoma, and six with clear cell carcinoma. The highest attenuation value of tumors in the corticomedullary phase (CMP) and the excretory phase (EP) was measured using the observer-defined region of interest (ROI). MRI consisted of T1-weighted and T2-weighted spin-echo imaging. RESULTS: All five tumors except for one with papillary renal cell carcinoma showed homogenous hypointensity, but all six tumors with clear cell carcinoma showed heterogeneous hyperintensity on their T2-weighted images. In the CMP, the mean CT numbers of the papillary renal cell carcinomas were significantly lower than those of the clear cell carcinomas. The mean enhancement of the papillary renal cell carcinomas in the CMP and the EP was significantly lower than that of the clear renal cell carcinomas. The mean CT numbers of the clear cell carcinomas in the CMP were markedly increased from those on the unenhanced CT; those in the EP were decreased gradually. But the mean CT numbers of the papillary renal cell carcinomas in the EP were still slightly more increased than those in the CMP. The enhancement patterns of the papillary renal cell carcinomas in the CMP and the EP were homogenous, but those of the clear cell carcinomas were heterogeneous. CONCLUSIONS: We can speculate the differential diagnosis from clear to papillary renal cell carcinoma using MRI and dual-phase helical CT.

[A case report of hepatocellular carcinoma with portal thrombus responding to hepatic arterial infusion chemo-lipiodolization].

A 73-year old man with multiple hepatocellular carcinomas underwent 4 transarterial chemoembolizations, but a tumor thrombus appeared in the left portal vein. The tumor sizes in segments 4 and 5 were 4.0 cm and 2.4 cm, respectively. The serum levels of AFP and PIVKA-II were 14,991 ng/ml and 15,944 mAU/ml, respectively. The tumor was 5-FU palpable in the epigastric region. Four ml of SMANCS and 4 ml of Lipiodol were injected to proper hepatic artery using the Seldinger technique. In addition, epirubicin (20 mg), MMC (4 mg) and Lipiodoi (2 ml) were injected into a proper hepatic artery via a reservoir every 3 weeks. The tumor was not palpable, and the tumor markers were markedly reduced after 2 months. The evaluation of response to the treatment was a partial response 3 months and 6 months later. Chemo-lipiodolization was very useful for advanced hepatocellular carcinoma with portal vein thrombus.

Detection of hypervascular hepatocellular carcinoma: comparison of SPIO-enhanced MRI with dynamic helical CT.

PURPOSE: The purpose of this study was to compare the diagnostic performance of superparamagnetic iron oxide (SPIO)-enhanced MRI for the detection of hypervascular hepatocellular carcinoma (HCC) with dynamic helical CT. METHODS: SPIO-enhanced MR and dynamic helical CT images obtained from 41 patients with 52 hypervascular HCCs (5-130 mm; mean, 27 mm) were retrospectively analyzed. MRI were obtained with 1.5 T scanners using T2-weighted and proton density-weighted spin-echo (or fast spin-echo) sequences for all cases and a T2*-weighted gradient echo sequence for 36 cases. Four blinded observers reviewed images independently. Diagnostic accuracy was evaluated using alternative-free response receiver operating characteristic (AFROC) method. Sensitivities and positive predictive values (PPV) were also evaluated. RESULTS: The areas under the AFROC curves for each observer were greater for MR than for CT (means, 0.81 and 0.76; p < 0.05). The mean sensitivities for MR and CT were 0.75 and 0.71, respectively (p = 0.13). The mean PPVs were 0.83 and 0.79 (p = 0.21). CONCLUSION: SPIO-enhanced MRI showed slightly better diagnostic performance than dynamic helical CT for the detection of hypervascular HCCs.