Genetics and imaging of hepatocellular adenomas: 2011 update.

Hepatocellular adenomas are benign liver neoplasms with specific but varied histopathologic findings and tumor biology. The results from recent studies of the pathologic and genetic basis of hepatocellular adenomas provide important insights into the pathogenesis and molecular changes, as well as the putative oncologic pathways used by diverse adenoma subtypes. On the basis of the genetic and pathologic features, hepatocellular adenomas are categorized into three distinct subtypes: (a) inflammatory hepatocellular adenomas, (b) hepatocyte nuclear factor 1 α-mutated hepatocellular adenomas, and (c) ß-catenin-mutated hepatocellular adenomas. Different subtypes show variable clinical behavior, imaging findings, and natural history, and thus the options for treatment and surveillance may vary. Cross-sectional imaging plays an important role in the diagnosis, subtype characterization, identification of complications, and surveillance of hepatocellular adenomas. New schemas for genotype-phenotype classification of hepatic adenomas, as well as management triage of patients with specific subtypes of adenomas, are being proposed in an attempt to improve clinical outcomes.

Wunderlich syndrome: cross-sectional imaging review.

Wunderlich syndrome (WS) is a rare condition characterized by acute onset of spontaneous, nontraumatic renal hemorrhage into the subcapsular and perirenal spaces. Wunderlich syndrome is classically characterized by the Lenk's triad: acute flank pain, flank mass, and hypovolemic shock. However, the clinical manifestations can be varied and nonspecific. A wide spectrum of neoplastic and nonneoplastic renal pathologies may result in WS. Renal neoplasms are the most common cause for WS, with angiomyolipoma being the most common benign neoplasm, whereas renal cell carcinoma is the most common malignant neoplasm. Other causative conditions of WS include vascular causes (vasculitis [polyarteritis nodosa being the most common cause], renal artery aneurysms, arteriovenous malformations and fistulas, and venous thrombosis), cystic renal diseases, renal infections, calculus disease, nephritis, and coagulation disorders. Cross-sectional imaging findings help in the detection of the subcapsular and/or perinephric hemorrhage and may identify underlying etiology. Renal angiography not only helps in diagnosis of the underlying cause in select cases but also allows control of active bleeding, which can avoid unnecessary emergent radical surgery.

Current update on borderline ovarian neoplasms.

OBJECTIVE: Borderline ovarian tumors comprise a unique group of noninvasive ovarian neoplasms with characteristic histology and variable tumor biology that typically manifest as low-stage disease in younger women with resultant excellent prognosis. CONCLUSION: Borderline tumors are considered to be precursors of low-grade ovarian cancers. Accurate diagnosis and staging facilitate optimal patient management particularly in patients desiring to preserve fertility.

Adult renal cystic disease: a genetic, biological, and developmental primer.

Renal cystic diseases in adults are a heterogeneous group of disorders characterized by the presence of multiple cysts in the kidneys. These diseases may be categorized as hereditary, acquired, or developmental on the basis of their pathogenesis. Hereditary conditions include autosomal dominant polycystic kidney disease, medullary cystic kidney disease, von Hippel-Lindau disease, and tuberous sclerosis. Acquired conditions include cystic kidney disease, which develops in patients with end-stage renal disease. Developmental cystic diseases of the adult kidney include localized renal cystic disease, multicystic dysplastic kidney, and medullary sponge kidney. In recent years, many molecular and cellular mechanisms involved in the pathogenesis of renal cystic diseases have been identified. Hereditary renal cystic diseases are characterized by genetic mutations that lead to defects in the structure and function of the primary cilia of renal tubular epithelial cells, abnormal proliferation of tubular epithelium, and increased fluid secretion, all of which ultimately result in the development of renal cysts. A better understanding of these pathophysiologic mechanisms is now providing the basis for the development of more targeted therapeutic drugs for some of these disorders. Cross-sectional imaging provides useful information for diagnosis, surveillance, prognostication, and evaluation of treatment response in renal cystic diseases.

Gestational trophoblastic disease.

Imaging plays a crucial role in diagnosis and management of gestational trophoblastic disease. Ultrasonography is the initial investigation of choice for the diagnosis. Pelvic magnetic resonance (MR) imaging is used as a problem-solving tool for assessment of degree of local invasion. Chest radiography is the recommended initial radiographic staging modality, and chest computed tomography is performed if the radiograph is negative. (18)F-Fluorodeoxyglucose positron emission tomography has been shown to be useful in assessing the active or viable sites of metastases, thereby determining the need for tumor resectability in chemoresistant disease.

Current concepts in the diagnosis and management of endometrial and cervical carcinomas.

Cross-sectional imaging modalities play a pivotal role in the diagnosis and multidisciplinary management of patients with endometrial and cervical carcinomas. Ultrasonography, including sonohysterography, permits evaluation of endometrial abnormalities and characterization of adnexal masses. Computed tomography, particularly in conjunction with (18)(F)-fluorodeoxyglucose positron emission tomography, is increasingly used to stage the cancers and to detect disease recurrence. Magnetic resonance imaging plays a major role in accurate locoregional staging of these cancers, and significantly influences treatment decisions and outcomes. This article discusses the role of imaging modalities in the diagnosis, management, and surveillance of these cancers.

Obstetric (nonfetal) complications.

Pregnancy predisposes women to a wide array of obstetric and gynecological complications which are often complex, challenging and sometimes life-threatening. While some of these are unique to pregnancy, a few that occur in nonpregnant women are more common during pregnancy. Imaging plays a crucial role in the diagnosis and management of pregnancy-related obstetric and gynecologic complications. Ultrasonography and magnetic resonance imaging confer the least risk to the fetus and should be the preferred examinations for evaluating these complications. Multidetector computed tomography should be used after carefully weighing the risk-benefit ratio based on the clinical condition in question. Interventional radiology is emerging as a preferred, noninvasive or minimally invasive treatment option that can obviate surgery and its antecedent short term and long term complications. Knowledge of appropriateness of imaging and image guided intervention is necessary for accurate patient management.

Rare, miscellaneous primary ovarian neoplasms: spectrum of cross-sectional imaging.

There is a diverse group of rare, primary benign and malignant ovarian tumors that show characteristic histomorphology and natural history. Some of these tumors may demonstrate typical imaging features. However, due to the rarity of these tumors, imaging characteristics of these diverse lesions are not well described in the literature. Knowledge of these select ovarian entities is essential and facilitates optimal management of patients who often manifest with nonspecific symptoms.