Regional lymph node involvement in urogenital malignancies (category N in the TNM classification system) is a significant radiologic finding, with important implications for treatment and prognosis. Male urogenital pelvic cancers commonly spread to iliopelvic or retroperitoneal lymph nodes by following pathways of normal lymphatic drainage from the pelvic organs. The most likely pathway of nodal spread (superficial inguinal, pelvic, or paraaortic) depends on the tumor location in the prostate, penis, testis, or bladder and whether surgery or other therapy has disrupted normal lymphatic drainage from the tumor site; knowledge of both factors is needed for accurate disease staging. At present, lymph node status is most often assessed with standard anatomic imaging techniques such as multidetector computed tomography or magnetic resonance (MR) imaging. However, the detection of nodal disease with these techniques is reliant on lymph node size and morphologic characteristics, criteria that provide limited diagnostic specificity. Functional imaging techniques, such as diffusion-weighted MR imaging performed with or without a lymphotropic contrast agent and positron emission tomography, may allow a more accurate nodal assessment based on molecular or physiologic activity.

Precise radiologic evaluation of regional adenopathic involvement in pelvic gynecologic tumors is fundamental to clinical practice because of its prognostic and therapeutic significance. Likewise, the identification of metastatic adenopathies at posttreatment imaging is essential for assessing response and detecting recurrence. Similar to urologic neoplasms, gynecologic neoplasms most often spread regionally to the pelvic and retroperitoneal lymph nodes, following the normal drainage pathways of the pelvic organs. Familiarity with routes of dissemination, treatment options, and means of analyzing lymph node characteristics is crucial to determine the extent of disease. Two staging systems can be used in characterizing gynecologic malignancies: the FIGO (International Federation of Gynecology and Obstetrics) system, which is the most commonly and universally used, and the TNM (tumor, node, metastasis) system, which is based on clinical and/or pathologic classification. Anatomic assessment with multidetector computed tomography (CT) and magnetic resonance (MR) imaging is still the most commonly used technique for the detection of lymph node spread, which is mainly based on morphologic criteria, the most important of which is nodal size. However, size has limited diagnostic specificity. Consequently, functional imaging techniques such as diffusion-weighted MR imaging, positron emission tomography combined with CT, lymphoscintigraphy, and sentinel lymph node mapping, which are based on molecular and physiologic activity and allow more precise evaluation, are often incorporated into diagnostic imaging protocols for staging of gynecologic malignancies.

CEUS is very useful in the differentiation between benign complex cysts and other lesions that require further investigation in non-conclusive renal nodules detected on CT, improving the accuracy of baseline US from 42.2 to 95.2%.

The detection of a renal mass is a relatively frequent occurrence in the daily practice of any Radiology Department. The diagnostic approaches depend on whether the lesion is cystic or solid. Cystic lesions can be managed using the Bosniak classification, while management of solid lesions depends on whether the lesion is well-defined or infiltrative. The approach to well-defined lesions focuses mainly on the differentiation between renal cancer and benign tumors such as angiomyolipoma (AML) and oncocytoma. Differential diagnosis of infiltrative lesions is wider, including primary and secondary malignancies and inflammatory disease, and knowledge of the patient history is essential. Radiologists may establish a possible differential diagnosis based on the imaging features of the renal masses and the clinical history. The aim of this review is to present the contribution of the different imaging techniques and image guided biopsies in the diagnostic management of cystic and solid renal lesions.

Most renal masses incidentally detected by cross-sectional images are benign, being mainly cysts, and if they are malignant, they are indolent in nature with limited metastatic potential. Enhanced renal masses less than 4 cm in size are known as small renal masses (SRMs), and their growth rate (GR) and the possibility of developing metastasis are extremely low. Delayed intervention of SRMs by closed and routine imaging follow-up known as active surveillance (AS) is now an option according to urological guidelines. Radiologists have a key position in AS management of SRMs even unifocal and multifocal (sporadic or associated with genetic syndromes) and also in the follow-up of complex renal cysts by Bosniak cyst classification system. Radiologists play a key role in the AS of both unifocal and multifocal (sporadic or associated with genetic syndromes) SRMs as well as in the follow-up of complex renal cysts using the Bosniak cyst classification system. Indeed, radiologists must determine which patients with SRMs or complex renal cysts can be included in AS, establish the follow-up radiological test algorithm to be used in different scenarios, perform measurements in follow-up tests, and decide when AS should be discontinued. The purpose of this article is to review the indications and management of AS in SRMs, especially focused on specific scenarios, such as complex renal cysts and multifocal renal tumors (sporadic or hereditary). In this work, the authors aimed to provide a thorough review of imaging in the context of active surveillance of renal masses.

No abstract

Adenoma malignum (AM) is considered a rare subtype of cervical adenocarcinoma. Although previous reports have described magnetic resonance findings, none of these reports evaluated the utility of diffusion-weighted imaging in the differential diagnosis of AM and other multicystic cervical lesions. We present a case report of an AM that did not show restriction on the apparent diffusion coefficient map, which can be explained by the low cellularity of the tumor. This is consistent with the proper correlation between the diffusion imaging and histopathology of the tumor. In this way, AM can present with high apparent diffusion coefficient values, as in benign cervical lesions. Therefore, the combination of a solid multicystic lesion that invades the cervical stroma on T2-weighted magnetic resonance images and the absence of restriction on the apparent diffusion coefficient map are very suggestive of AM.

PurposeTo evaluate the accuracy of unenhanced magnetic resonance angiography (U-MRA) using balanced steady-state free precession (SSFP) sequences with inversion recovery (IR) pulses for the evaluation of renal artery stenosis.Materials and methodsU-MRA was performed in 24 patients with suspected main renal artery stenosis. Two radiologists evaluated the quality of the imaging studies and the ability of U-MRA to identify hemodynamically significant main renal artery stenosis (RAS) defined as a stenosis ≥50% when compared to gold standard tests: contrast-enhanced magnetic resonance angiography (CE-MRA) (18 patients) or digital subtraction arteriography (DSA) (6 patients).ResultsA total of 44 main renal arteries were evaluated. Of them, 32 renal arteries could be assessed with U-MRA. When CE-MRA or DSA was used as the reference standard, nine renal arteries had hemodynamically significant RAS. U-MRA correctly identified eight out of nine arteries as having ≥50% RAS, and correctly identified 22 out of 23 arteries as not having significant RAS, with a sensitivity of 88.8%, a specificity of 95.65%, positive and negative predictive value of 88.8% and 95.65%, respectively, and an accuracy of 93.75%. Renal artery fibromuscular dysplasia (FMD) was observed in the two misclassified arteries.ConclusionU-MRA is a reliable diagnostic method to depict normal and stenotic main renal arteries. U-MRA can be used as an alternative to contrast-enhanced magnetic resonance angiography or computer tomography angiography in patients with renal insufficiency unless FMD is suspected.