Imaging protocols for renal multiparametric MRI and MR urography: results of a consensus conference from the French Society of Genitourinary Imaging.

OBJECTIVES: To develop technical guidelines for magnetic resonance imaging aimed at characterising renal masses (multiparametric magnetic resonance imaging, mpMRI) and at imaging the bladder and upper urinary tract (magnetic resonance urography, MRU). METHODS: The French Society of Genitourinary Imaging organised a Delphi consensus conference with a two-round Delphi survey followed by a face-to-face meeting. Two separate questionnaires were issued for renal mpMRI and for MRU. Consensus was strictly defined using a priori criteria. RESULTS: Forty-two expert uroradiologists completed both survey rounds with no attrition between the rounds. Fifty-six of 84 (67%) statements of the mpMRI questionnaire and 44/71 (62%) statements of the MRU questionnaire reached final consensus. For mpMRI, there was consensus that no injection of furosemide was needed and that the imaging protocol should include T2-weighted imaging, dual chemical shift imaging, diffusion-weighted imaging (use of multiple b-values; maximal b-value, 1000 s/mm2) and fat-saturated single-bolus multiphase (unenhanced, corticomedullary, nephrographic) contrast-enhanced imaging; late imaging (more than 10 min after injection) was judged optional. For MRU, the patients should void their bladder before the examination. The protocol must include T2-weighted imaging, anatomical fast T1/T2-weighted imaging, diffusion-weighted imaging (use of multiple b-values; maximal b-value, 1000 s/mm2) and fat-saturated single-bolus multiphase (unenhanced, corticomedullary, nephrographic, excretory) contrast-enhanced imaging. An intravenous injection of furosemide is mandatory before the injection of contrast medium. Heavily T2-weighted cholangiopancreatography-like imaging was judged optional. CONCLUSION: This expert-based consensus conference provides recommendations to standardise magnetic resonance imaging of kidneys, ureter and bladder. KEY POINTS: • Multiparametric magnetic resonance imaging (mpMRI) aims at characterising renal masses; magnetic resonance urography (MRU) aims at imaging the urinary bladder and the collecting systems. • For mpMRI, no injection of furosemide is needed. • For MRU, an intravenous injection of furosemide is mandatory before the injection of contrast medium; heavily T2-weighted cholangiopancreatography-like imaging is optional.

Clear Cell Papillary Renal Cell Carcinoma: A Recent Entity With Distinct Imaging Patterns.

OBJECTIVE. Clear cell papillary renal cell carcinoma (RCC), an entity with strikingly indolent behavior, recently was added to the World Health Organization classification of renal tumors and represents the fourth most common histologic type of renal cell carcinoma. This article aims to describe the imaging features of clear cell papillary RCC along with its clinical and pathologic characteristics. MATERIALS AND METHODS. This retrospective study consisted of 27 patients with 44 clear cell papillary RCC tumors. The inclusion criteria were a pathologically proven clear cell papillary RCC and the availability of preoperative imaging including at least CT or MRI. Two experienced radiologists performed the imaging analysis independently. RESULTS. Patients (mean age, 62 years old) presented with renal failure in 26% of cases, and four had a tumor-predisposing disease. Multiple clear cell papillary RCC tumors occurred in 5 of the 27 patients. Two imaging patterns were recognizable. Solid clear cell papillary RCC (n = 23, 52%) presented as heterogeneous tumors with minor cystic changes (74%) and rarely exhibited calcifications (10%). All solid tumors showed hyperintensity on T2-weighted images compared with renal cortex and maximal enhancement on corticomedullary phase with a delayed washout. Cystic clear cell papillary RCC (n = 21, 48%) were classified as Bosniak IV (57%), III (33%), or IIF (10%), with a predominant unilocular pattern (76%). Pathologic stage according to TNM classification was mostly pT1a and low grade on nucleolar grade. All patients were alive at the date of last follow-up after treatment with no metastasis or recurrence. CONCLUSION. Clear cell papillary RCC exhibits two imaging patterns including cystic and solid in almost equal proportion. Imaging characteristics of solid clear cell papillary RCC including high signal T2 intensity and early arterial enhancement are unexpectedly distinct from papillary RCC and very similar to clear cell RCC.

Imaging protocols for CT urography: results of a consensus conference from the French Society of Genitourinary Imaging.

OBJECTIVES: To develop technical guidelines for computed tomography urography. METHODS: The French Society of Genitourinary Imaging organised a Delphi consensus conference with a two-round Delphi survey followed by a face-to-face meeting. Consensus was strictly defined using a priori criteria. RESULTS: Forty-two expert uro-radiologists completed both survey rounds with no attrition between the rounds. Ninety-six (70%) of the initial 138 statements of the questionnaire achieved final consensus. An intravenous injection of 20 mg of furosemide before iodinated contrast medium injection was judged mandatory. Improving the quality of excretory phase imaging through oral or intravenous hydration of the patient or through the use of an abdominal compression device was not deemed necessary. The patient should be imaged in the supine position and placed in the prone position only at the radiologist's request. The choice between single-bolus and split-bolus protocols depends on the context, but split-bolus protocols should be favoured whenever possible to decrease patient irradiation. Repeated single-slice test acquisitions should not be performed to decide of the timing of excretory phase imaging; instead, excretory phase imaging should be performed 7 min after the injection of the contrast medium. The optimal combination of unenhanced, corticomedullary phase and nephrographic phase imaging depends on the context; suggestions of protocols are provided for eight different clinical situations. CONCLUSION: This expert-based consensus conference provides recommendations to standardise the imaging protocol for computed tomography urography. KEY POINTS: • To improve excretory phase imaging, an intravenous injection of furosemide should be performed before the injection of iodinated contrast medium. • Systematic oral or intravenous hydration is not necessary to improve excretory phase imaging. • The choice between single-bolus and split-bolus protocols depends on the context, but split-bolus protocols should be favoured whenever possible to decrease patient irradiation.

Spontaneous gas in a retroperitoneal mass: check the testis!

ABSTRACT Testicular germ cell tumor is the most common cancer in 20-to 35-years-old men. There are known risk factors such as undescended testicle(s) and history of testicular cancer. Most lesions are germ cell tumors with two main subtypes: seminomas and non-seminomatous germ cell tumors.

Spontaneous gas in a retroperitoneal mass: check the testis!

Testicular germ cell tumor is the most common cancer in 20-to 35-years-old men. There are known risk factors such as undescended testicle(s) and history of testicular cancer. Most lesions are germ cell tumors with two main subtypes: seminomas and non-seminomatous germ cell tumors.

Renal Pseudo-tumor Related to Renal Splenosis: Imaging Features.

OBJECTIVE: To report the case of a 29-year-old patient presenting with renal splenosis along with a complete review of literature on this condition. Splenosis is a frequent condition following abdominal trauma or splenectomy, described as splenic tissue that autotransplants into a heterotopic location. However, renal splenosis is rare and often mistaken with renal carcinoma. MATERIALS AND METHODS: The patient was initially referred to our department for a renal mass incidentally discovered on ultrasound. Further investigation included with computed tomography and magnetic resonance imaging. RESULTS: Imaging features revealed a well circumscribed solid renal mass, exhibiting an isosignal on T1- and T2-weighted sequences in comparison with the renal cortex. The mass exhibited a heterogeneous enhancement on the arterial and portal phases, homogeneous patterns during the delayed phases, and high signal intensity on diffusion-weighted images. A partial nephrectomy was performed and pathological examination revealed the final diagnosis of renal splenosis. CONCLUSION: Imaging features alone do not provide a definitive diagnosis of splenosis but suggestive past history associated with imaging findings consistent with splenic tissue should lead to 99m technetium-sulfur colloid scanning or ferumoxid-enhanced MRI to avoid useless surgery.

Calcified Renal Angiomyolipoma: A Case Report.

We report the case of a calcified angiomyolipoma of the kidney, fortuitously discovered on a computed tomography scan of the abdomen. Because of the presence of intratumoral calcification and macroscopic fat, renal cell carcinoma could not be ruled out by imaging. Biopsy of the mass was performed, and pathological study confirmed the diagnosis of angiomyolipoma. Biopsy of renal masses containing macroscopic fat and calcification may be considered before nephrectomy.

Optimization of 64-MDCT urography: effect of dual-phase imaging with furosemide on collecting system opacification and radiation dose.

OBJECTIVE: The purpose of this study was to compare opacification of the urinary collecting system and radiation dose associated with three-phase 64-MDCT urographic protocols and those associated with a split-bolus dual-phase protocol including furosemide. MATERIALS AND METHODS: Images from 150 CT urographic examinations performed with three scanning protocols were retrospectively evaluated. Group A consisted of 50 sequentially registered patients who underwent a three-phase protocol with saline infusion. Group B consisted of 50 sequentially registered patients who underwent a reduced-radiation three-phase protocol with saline. Group C consisted of 50 sequentially registered patients who underwent a dual-phase split-bolus protocol that included a low-dose furosemide injection. Opacification of the urinary collecting system was evaluated with segmental binary scoring. Contrast artifacts were evaluated, and radiation doses were recorded. Results were compared by analysis of variance. RESULTS: A significant reduction in mean effective radiation dose was found between groups A and B (p < 0.001) and between groups B and C (p < 0.001), resulting in 65% reduction between groups A and C (p < 0.001). This reduction did not significantly affect opacification score in any of the 12 urinary segments (p = 0.079). In addition, dense contrast artifacts overlying the renal parenchyma observed with the three-phase protocols (groups A and B) were avoided with the dual-phase protocol (group C) (p < 0.001). CONCLUSION: A dual-phase protocol with furosemide injection is the preferable technique for CT urography. In comparison with commonly used three-phase protocols, the dual-phase protocol significantly reduces radiation exposure dose without reduction in image quality.

Hybrid tumour 'oncocytoma-chromophobe renal cell carcinoma' of the kidney: a report of seven sporadic cases.

OBJECTIVES: To determine whether renal hybrid tumours (HT) appear as a specific clinical and radiological entity, as HT are characterized by the association of both oncocytes and chromophobe cells within the same tumour, and have been described in patients with oncocytosis and Birt-Hogg-Dube syndrome. PATIENTS AND METHODS: We reviewed the medical charts of 67 patients who had a partial or radical nephrectomy in our institution for renal oncocytoma (RO, 24), chromophobe renal cell carcinoma (CRCC, 36) and HT (seven), from January 2006 to October 2007. We report the clinical, radiological and pathological characteristics of the seven cases of HT. RESULTS: The mean (range) age of the patients was 56 (41-68) year. None of the seven patients had any suspicion of RO, based on computed tomography (CT). Two patients had a history of kidney cancer. Five patients had partial and two a radical nephrectomy. The mean (range) maximum tumour diameter was 5.5 (1.8-9) cm. Two tumours were pT1a, two were pT1b and three were pT2. Pathological analysis showed RO-like and CRCC-like cells intermixed (six patients) or distinct (one). After a median (range) follow-up of 20 (8-25) months, none of the patients had any evidence of disease recurrence. CONCLUSIONS: In a large series of patients with sporadic RO and CRCC, 10% of the tumours had hybrid morphological features, as described in oncocytosis and Birt-Hogg-Dube syndrome. We were unable to identify any specific clinical characteristic. Most importantly, none of these HT showed any of the radiological characteristics of RO.

[Laparoscopic kidney release for refractory chyluria]. / Néphrolyse laparoscopique pour chylurie réfractaire.

Chyluria is a rare disease outside of parasite endemic zones. The treatment of severe forms is surgical. Reno-lymphatic disconnection is the reference procedure, with long-term success rates of 99%. This operation performed via a lumbar incision can also be performed by retroperitoneal or transperitoneal laparoscopy. The advantages of this minimally invasive incision are those classically reported in the literature.

[Imaging of cancer prostate]. / Imagerie du cancer de la prostate.

Imaging of prostate cancer relies mainly on ultrasonography (US) and magnetic resonance imaging (MRI). It plays a diagnostic role in detecting and staging prostate carcinomas. Prostate biopsies are performed under endorectal US guidance at best with additional colour Doppler information. US also may provide useful information regarding the significance of an abnormal digital rectal examination sometimes related to some benign prostate alterations that can mimic a neoplastic nodule. In all cases imaging studies need to be interpreted in light of clinical and biological data including the results of biopsy especially in staging carcinoma with MR. Finally, CT and scintigraphy are helpful in screening for distant metastases.