Madhavi Patnana

Inflammatory Pseudotumor: The Great Mimicker

OBJECTIVE The purpose of this review is to describe the pathophysiologic findings, differential diagnosis, imaging features, and management of inflammatory pseudotumor in various locations throughout the body. CONCLUSION Inflammatory pseudotumor is a rare benign process mimicking malignant processes and has been found in almost every organ system. Radiologists should be familiar with this entity as a diagnostic consideration to avoid unnecessary surgery.

The inguinal canal: anatomy and imaging features of common and uncommon masses.

A variety of benign and malignant masses can be found in the inguinal canal (IC). Benign causes of masses in the IC include spermatic cord lipoma, hematoma, abscess, neurofibroma, varicocele, desmoid tumor, air, bowel contrast material, hydrocele, and prostheses. Primary neoplasms of the IC include liposarcoma, Burkitt lymphoma, testicular carcinoma, and sarcoma. Metastases to the IC can occur from alveolar rhabdomyosarcoma, monophasic sarcoma, prostate cancer, Wilms tumor, carcinoid tumor, melanoma, or pancreatic cancer. In patients with a known malignancy and peritoneal carcinomatosis, the diagnosis of metastases can be suggested when a mass is detected in the IC. When peritoneal disease is not evident, a mass in the IC is indicative of stage IV disease and may significantly alter clinical and surgical treatment of the patient. A combination of the clinical history, symptoms, laboratory values, and radiologic features aids the radiologist in accurately diagnosing mass lesions of the IC. Supplemental material available at radiographics.rsnajnls.org/cgi/content/full/28/3/819/DC1.

Multimethod imaging, staging, and spectrum of manifestations of metastatic melanoma

The incidence of melanoma has been steadily increasing. Imaging plays an important role in tumour assessment as metastatic melanoma can involve multiple organs. Computed tomography (CT) is currently the most widely used technique for tumour staging, surveillance and assessment of therapeutic response, but ultrasound, magnetic resonance imaging (MRI) and positron-emission tomography (PET)-CT also play important roles in the imaging of this tumour. In this article, we review the pathways of spread, staging according to the recently updated TNM classification, pathology, typical and atypical imaging features at common and uncommon sites, and treatment of metastatic melanoma.

Multimodality imaging of common and uncommon peritoneal diseases: a review for radiologists.

Peritoneal disease can be caused by a wide spectrum of pathologies. While peritoneal disease is usually caused by primary or secondary malignancies, benign diseases can occur and mimic malignancies. This article begins with an overview of peritoneal embryology and anatomy followed by a detailed description of the multimodality imaging appearance of peritoneal diseases. Common diseases include peritoneal carcinomatosis, pseudomyxoma peritonei, lymphomatosis, sarcomatosis, and tuberculous peritonitis. The uncommon diseases which cause peritoneal disease include desmoid fibromatosis, desmoplastic small round cell tumor, malignant mesothelioma, well-differentiated mesothelioma, multicystic mesothelioma, papillary serous carcinoma, leiomyomatosis, extramedullary hematopoiesis, inflammatory pseudotumor and amyloidosis. This manuscript will help the radiologist become familiar with the different peritoneal spaces, pathways of spread, multimodality imaging appearance and differential diagnoses of peritoneal diseases in order to report the essential information for surgeons and oncologists to plan treatment.

Pancreatic neuroendocrine neoplasms: diagnosis and management

Pancreatic neuroendocrine neoplasms are uncommon but rising in incidence. There have been recent changes in the WHO nomenclature and a newly proposed American Joint Committee on Cancer TNM staging, which complement each other. These neoplasms are of great medical and radiological interest because of their diverse presenting features and imaging appearances. There is an increased role for both anatomic and functional imaging in the assessment of these neoplasms. A review of the nomenclature, staging, and imaging is presented in this paper.

Intraoperative abdominal ultrasound in oncologic imaging

Significant advances in ultrasound technology have created new opportunities for its use in oncologic imaging. The advent of new transducers with focal beam technology and higher frequency has solidified the role of intraoperative sonography (IOUS) as an invaluable imaging modality in oncologic surgery of the liver, kidneys and pancreas. The ability to detect and characterize small lesions and the precise intraoperative localization of such tumors is essential for adequate surgical planning in segmental or lobar hepatic resections, metastasectomy, nephron-sparing surgery, and partial pancreatectomy. Also, diagnostic characterization of small equivocal lesions deemed indeterminate by conventional preoperative imaging such as multidetector computed tomography or magnetic resonance imaging, has become an important application of IOUS. This article will review the current applications of IOUS in the liver, kidneys and pancreas.

Ewing Sarcoma of the Kidney: A Rare Entity

Ewing sarcoma and primitive peripheral neuroectodermal tumor (PNET) are high-grade malignant tumors typically found in children and adolescents. These tumors belong to the family of small round cell tumors and are of neuroectodermal origin. Primary Ewing sarcoma of the kidney is rare and because of that is an infrequent differential diagnosis in urologic malignancies. Renal PNET mostly presents with nonspecific symptoms such as hematuria and abdominal pain. The imaging findings are uncharacteristic. The diagnosis is based on the histology, immunohistochemistry, and molecular pathologic findings. Once PNET has been diagnosed, multimodal treatment is indicated. Despite all treatment options, the prognosis of those with metastatic disease is poor.

Pancreatic Calcifications and Calcified Pancreatic Masses: Pattern Recognition Approach on CT

OBJECTIVE The purpose of this article is to review a spectrum of calcified pancreatic masses and propose an algorithm for diagnostic radiologic evaluation. CONCLUSION Pancreatic calcifications are being detected more frequently because of the widespread use of imaging, particularly CT. Pancreatic calcifications are most commonly associated with chronic pancreatitis related to alcohol abuse. Several other pathologic entities, however, can cause pancreatic calcifications. Familiarity with these entities and their CT appearance is helpful in making an accurate diagnosis.

Abdominal and Pelvic Complications of Nonoperative Oncologic Therapy

Oncologic patients are treated with a combination of chemotherapy, radiation therapy, and surgery. Advances in therapeutic options have greatly improved the survival of patients with cancer. Examples of these advances are newer chemotherapeutic agents that target the cell receptors and advanced radiation therapy delivery systems. It is imperative that radiologists be aware of the variety of imaging findings seen after therapy in patients with cancer. Complications may occur with classic cytotoxic therapies (eg, 5-fluorouracil), usually at higher or prolonged doses or when administered to radiosensitive areas. Newer targeted systemic agents, such as bevacizumab and imatinib, have associated characteristic toxicities because their effects on cells do not depend on dose. Radiation may induce early and late effects in local normal tissues that may be seen at imaging. Imaging findings after chemotherapy include fatty liver, pseudocirrhosis, hepatic veno-occlusive disease, and splenic rupture. Complications of radiation therapy include large and small bowel strictures and radiation-induced hepatitis and tumors. Awareness of the various therapeutic options and knowledge of the spectrum of posttherapeutic complications allows radiologists to provide a comprehensive report that may impact patient management.

Can abdominal computed tomography imaging help accurately identify a dedifferentiated component in a well-differentiated liposarcoma?

Purpose To assess the ability of computed tomography (CT) to differentiate an atypical lipomatous tumor/well-differentiated liposarcoma (WDLPS) from a WDLPS with a dedifferentiated component (DDLPS) within it. Materials and Methods Forty-nine untreated patients with abdominal atypical lipomatous tumors/well-differentiated liposarcomas who had undergone contrast-enhanced CT were identified using an institutional database. Three radiologists who were blinded to the pathology findings evaluated all the images independently to determine whether a dedifferentiated component was present within the WDLPS. The CT images were evaluated for fat content (⩽25% or >25%); presence of ground-glass density, enhancing and/or necrotic nodules; presence of a capsule surrounding the mass; septations; and presence and pattern of calcifications. A multivariate logistic regression model with generalized estimating equations was used to correlate imaging features with pathology findings. Kappa statistics were calculated to assess agreement between the three radiologists. Results On the basis of pathological findings, 12 patients had been diagnosed with DDLPS within a WDLPS and 37 had been diagnosed with WDLPS. The presence of an enhancing or a centrally necrotic nodule within the atypical lipomatous tumor was associated with dedifferentiated liposarcoma (P = 0.02 and P = 0.0003, respectively). The three readers showed almost perfect agreement in overall diagnosis (&kgr; r = 0.83; 95% confidence interval, 0.67–0.99). Conclusions An enhancing or centrally necrotic nodule may be indicative of a dedifferentiated component in well-differentiated liposarcoma. Ground-glass density nodules may not be indicative of dedifferentiation.