Value of triphasic MDCT in the differentiation of small renal cell carcinoma and oncocytoma.

INTRODUCTION: Although differentiation between benign and malignant small renal tumors (≤4 cm) is still difficult, it is a demand for decision making and determining the treatment strategy. Our aim is to evaluate the role of multidetector row computed tomography (MDCT) in the differentiation of small renal clear cell carcinoma (RCC) and renal oncocytoma (RO). METHODS: We reviewed triphasic computed tomographic (CT) scans performed in 43 patients diagnosed with RCC (n = 23) and RO (n = 21). After an unenhanced CT phase of the upper abdomen, triple-phase acquisition included a cortico-medullary phase (CMP), a nephrographic phase (NP), and a pyelographic phase (PP), and lesions were evaluated both qualitatively and quantitatively. RESULTS: RCCs were hypervascular in 13 cases and hypovascular in 10 cases, while ROs were hypervascular in nine cases and hypovascular in 12 cases. Mean attenuation values (MAVs) for hypervascular RCCs and hypervascular ROs on unenhanced examination were 34.0 ± 7.1 and 31.3 ± 8.1 HU, respectively. Enhancement in CMP was 173.1 ± 45.2 HU for RCCs and 151.1 ± 36.0 HU for ROs and a gradual wash-out in NP (148.8 ± 34.3 and 137.1 ± 33.9 HU for RCCs and ROs, respectively) and in PP (98.2 ± 36.0 HU for RCCs and 79.4 ± 21.5 HU for ROs) was observed. MAV for hypovascular RCCs and hypovascular ROs on unenhanced examination were 32.4 ± 12.0 and 28.9 ± 8.0 HU, respectively. Both hypovascular RCCs and ROs showed a statistically significant difference in each post contrastographic phase. CONCLUSIONS: Absolute attenuation and the quantitative amount of the enhancement were not strong predictors for RO and RCC differentiation.

Biparametric versus Multiparametric MRI with Non-endorectal Coil at 3T in the Detection and Localization of Prostate Cancer.

AIM: To assess the sensitivity of biparametric magnetic resonance imaging (bpMRI) with non-endorectal coil in the detection and localization of index (dominant) and non-index lesions in patients suspected of having prostate cancer. PATIENTS AND METHODS: We carried-out a retrospective analysis of multiparametric MRI (mpMRI) of 41 patients who underwent radical prostatectomy. Results of MRI for detection and localization of index and non-index lesions were correlated with those of histology. RESULTS: No statistically significant difference in size was seen between tumor lesion at histology and index lesion at MRI. In 41 patients, a total of 131 tumors were identified at histology, while bpMRI (T2-weighted and diffusion-weighted MRI) approach detected 181 lesions. bpMRI gave 27.6% false-positives and 3.3% false-negatives. Sensitivity in lesion detection by bpMRI increased with lesion size assuming high values for lesions ≥10 mm. For bpMRI and mpMRI, the sensitivity for detecting index lesions was the same and equal: 100% in the peripheral zone 97.6% and 94.7% in the entire prostate and transitional zone, respectively. CONCLUSION: bpMRI can be used alternatively to mpMRI to detect and localize index prostate cancer.