Comprehensive Review of Abdominopelvic Mesenchymal Tumors With Radiologic Pathologic Correlation and Update on Current Treatment Guidelines-Part 2.

Soft-tissue sarcomas are a diverse group of rare mesenchymal malignancies accounting for only 1% of all solid adult malignancies. These have been categorized in 12 broad groups by the World Health Organization (WHO) with their recent update in 2013. Majority of them lack specific imaging features serving as imaging conundrums for a radiologist. These are often large masses at presentation as they are asymptomatic or cause vague clinical symptoms. These tumors are challenging for surgeons as well as they find it difficult to achieve complete resection because of complex intra-abdominal anatomy and their close relationship with critical structures. Often, a multidisciplinary approach is required to decide on the most appropriate management for these complex cases so as to provide optimal patient care. Knowledge of the WHO classification, pathologic features, and treatment options available helps the radiologist make a meaningful contribution in multidisciplinary discussions of such cases and overall patient care. Liposarcoma (well-differentiated and dedifferentiated liposarcomas), leiomyosarcoma, and gastrointestinal stromal tumor are the 3 most common primary intra-abdominal sarcomas. In part 1 of this article, general features of soft-tissue sarcomas and some of the common tumors from WHO category 1-4 found in abdomen and pelvis are discussed. Part 2 will focus on common tumors from remainder of the WHO categories.

Comprehensive Review of Abdominopelvic Mesenchymal Tumors with Radiologic Pathologic Correlation and Update on Current Treatment Guidelines - Part 1.

Soft-tissue sarcomas are a diverse group of rare mesenchymal malignancies accounting for only 1% of all solid adult malignancies. These have been categorized in 12 broad groups by the World Health Organization (WHO) with their recent update in 2013. Majority of them lack specific imaging features serving as imaging conundrums for a radiologist. These are often large masses at presentation as they are asymptomatic or cause vague clinical symptoms. These tumors are challenging for surgeons as well as they find it difficult to achieve complete resection because of complex intra-abdominal anatomy and their close relationship with critical structures. Often, a multidisciplinary approach is required to decide on the most appropriate management for these complex cases so as to provide optimal patient care. Knowledge of the WHO classification, pathologic features and available treatment options will help the radiologist make a meaningful contribution in multidisciplinary discussions of such cases and overall patient care. Liposarcoma (well-differentiated and dedifferentiated liposarcomas), leiomyosarcoma, and gastrointestinal stromal tumor are the 3 most common primary intra-abdominal sarcomas. In part 1 of this article, general features of soft tissue sarcomas and some of the common tumors from WHO category 1-4 found in abdomen and pelvis are discussed. Part 2 will focus on common tumors from remainder of the WHO categories.

Ossified dysraphic hamartoma with lipomyelocoele/lipomyelomeningocoele-A rare radiological entity.

Traditionally the presence of fat in closed spinal dysraphism has been referred to as spinal lipoma. Recent reports suggest that these spinal lesions are better described as spinal hamartomas due to the unencapsulated and infiltrating nature of the fat and presence of other heterotopic soft tissue. The presence of ossified bone in spinal hamartomas referred to as ossified dysraphic hamartoma, is extremely rare with only three case reports in literature, all associated with lipomyeloceles, none with lipomyelomeningoceles. We present three cases of ossified dysraphic hamartoma, two of them associated with lipomyelomeningoceles, reviewing imaging features on CT and MRI.

Update on Gastrointestinal Stromal Tumors for Radiologists.

The management of gastrointestinal stromal tumors (GISTs) has evolved significantly in the last two decades due to better understanding of their biologic behavior as well as development of molecular targeted therapies. GISTs with exon 11 mutation respond to imatinib whereas GISTs with exon 9 or succinate dehydrogenase subunit mutations do not. Risk stratification models have enabled stratifying GISTs according to risk of recurrence and choosing patients who may benefit from adjuvant therapy. Assessing response to targeted therapies in GIST using conventional response criteria has several potential pitfalls leading to search for alternate response criteria based on changes in tumor attenuation, volume, metabolic and functional parameters. Surveillance of patients with GIST in the adjuvant setting is important for timely detection of recurrences.

Current Concepts in Non-Gastrointestinal Stromal Tumor Soft Tissue Sarcomas: A Primer for Radiologists.

Non-gastrointestinal stromal tumor (GIST) soft tissue sarcomas (STSs) are a heterogeneous group of neoplasms whose classification and management continues to evolve with better understanding of their biologic behavior. The 2013 World Health Organization (WHO) has revised their classification based on new immunohistochemical and cytogenetic data. In this article, we will provide a brief overview of the revised WHO classification of soft tissue tumors, discuss in detail the radiology and management of the two most common adult non-GIST STS, namely liposarcoma and leiomyosarcoma, and review some of the emerging histology-driven targeted therapies in non-GIST STS, focusing on the role of the radiologist.

Primary Extremity Liposarcoma: MRI Features, Histopathology, and Clinical Outcomes.

OBJECTIVE: This study aimed to describe magnetic resonance imaging (MRI) features of extremity liposarcoma (LPS) subtypes, correlating with histopathology and clinical outcomes. METHODS: In this retrospective study, we included 125 patients (80 men, 45 women; mean age, 53 years) with extremity LPS [23 atypical lipomatous tumor (ALT), 9 dedifferentiated (DDLPS), 70 myxoid (MLPS), 23 pleomorphic (PLPS)]. Pretreatment MRI of primary tumors in 56 patients (10 ALT, 4 DDLPS, 28 MLPS, 14 PLPS) was reviewed. RESULTS: All subtypes were predominantly T1 isointense relative to skeletal muscle (DDLPS = 3/4, MLPS = 28/28, PLPS = 13/14) and T2 hyperintense (ALT = 10/10, DDLPS = 3/4, MLPS = 28/28, PLPS = 14/14) except for ALT which were T1 hyperintense (8/10). Within MLPS, high grade was associated with unencapsulated margins (P = 0.05) and solid, nodular enhancement (P < 0.0001). Peritumoral edema (P = 0.03) and T2 heterogeneity (P = 0.05) predicted pulmonary (rather than extrapulmonary) metastases in MLPS. Tumor subtype correlated with mortality (P = 0.04). CONCLUSIONS: The MRI features can help to distinguish between extremity LPS subtypes, and can predict histopathologic grade and metastatic pattern in myxoid LPS.

Neoadjuvant radiation in primary extremity liposarcoma: correlation of MRI features with histopathology.

OBJECTIVE: To evaluate MRI features of response of primary extremity liposarcoma (LPS) to neoadjuvant radiation therapy (RT) with histopathologic correlation. METHODS: In this IRB-approved study including 125 patients with extremity LPS treated with neoadjuvant RT from 2000 to 2013, MRI of the primary tumour in 18 patients (5 pleomorphic LPS, 13 myxoid LPS) before and after RT were reviewed by two radiologists by consensus. Histopathology of the surgical specimens was reviewed by a pathologist with expertise in sarcomas. RESULTS: In the pleomorphic LPS cohort, 3/5 tumours increased in size; 3/5 decreased in enhancing component; and 3/5 increased in peritumoral oedema, intratumoral haemorrhage, and necrosis. In the myxoid LPS cohort, 12/13 tumours decreased in size, 8/13 decreased in enhancing component, and 5/13 increased in internal fat following RT. Histopathology showed ≥50% residual tumour in 1/5 pleomorphic LPS and 2/13 myxoid LPS. Hyalinization/necrosis of ≥75% was noted in 4/5 pleomorphic LPS and 11/13 myxoid LPS. Cytodifferentiation was noted in 1/5 pleomorphic and 9/13 myxoid LPS. CONCLUSION: While pleomorphic LPS showed an increase in size, peritumoral oedema, intratumoral haemorrhage, and necrosis on MRI following neoadjuvant RT, myxoid LPS showed a decrease in size and enhancement with an increase in internal fat. KEY POINTS: • Pleomorphic LPS commonly increase in size and necrosis on MRI following RT. • Myxoid LPS commonly decrease in size and enhancement on MRI following RT. • Myxoid LPS often increase in fatty component on MRI following RT.

Esophageal Carcinoma: Current Concepts in the Role of Imaging in Staging and Management.

Over the past few decades, the survival of esophageal cancer patients has improved owing to early detection and advances in multimodality treatment strategies. Imaging plays an important role in every step in the management of esophageal cancer, including diagnosis, staging, assessment of treatment response, and post-treatment surveillance. In this article, we provide a comprehensive review of the role of imaging in these various time points of esophageal cancer management.

Basal cell carcinoma: a comprehensive review for the radiologist.

OBJECTIVE. Basal cell carcinoma (BCC) is the most common malignancy in the United States. The purpose of this article is to provide a comprehensive description of the clinicopathologic features, diagnostic workup, staging, treatment, and follow-up of BCC. CONCLUSION. Radiology plays an important role in the evaluation and staging of locally advanced and metastatic BCC. MRI is the modality of choice for assessing perineural disease and is equivalent or superior to CT for evaluating bony involvement. CT and PET/CT are used to evaluate metastatic disease.

Is the nonlipomatous component of dedifferentiated liposarcoma always soft tissue on CT? Analysis of CT densities and correlation with rate of growth in 60 patients.

PURPOSE: To define the various CT densities of nonlipomatous component of dedifferentiated liposarcoma (DDLPS) and to determine if the rate of growth varies with density. METHODS: This study identified 60 patients with DDPLS (38 men, 22 women; mean age at diagnosis 59 years, range, 35-82 years) who had one or more resections. CT scan immediately before the surgical resection (presurgery) and up to a maximum of one year before the surgery (baseline) was reviewed by two radiologists to note the density of the nonlipomatous elements and rate of growth during that period. Clinical and histopathological data were extracted from electronic medical records. Rate of growth of various densities was compared using Kruskal-Wallis test. RESULTS: Three distinct densities of the nonlipomatous component were noted: soft tissue density (SD), fluid density (FD), and mixed density (MD). Of 109 lesions on the presurgery scan (SD = 78; MD = 22; FD = 9), scans at baseline were available for 72/109 lesions (SD = 49; MD = 14; FD = 9). Median growth rate/month without treatment, with chemotherapy, and with radiotherapy were 40%, 24%, and 62%, respectively, for SD lesions and 28%, 61%, and 52% for MD lesions. For FD lesions, it was 72% and 35%, respectively, without treatment and with chemotherapy. There was no statistical difference in the rate of growth of various densities. Density changed over time in 8/72 (11%) lesions, including 2/49 SD lesions (to MD), 1/14 MD lesions (to SD), and 5/9 FD lesions (to SD). CONCLUSIONS: DDLPS has three distinct CT densities of which soft tissue density is the most common. Despite not being statistically significant, fluid density lesions had rapid growth rate and often converted to soft tissue density in our study.

Metastatic pattern of uterine leiomyosarcoma: retrospective analysis of the predictors and outcome in 113 patients.

OBJECTIVE: To describe metastatic pattern of uterine leiomyosarcomas (ULMS) and correlate it with clinical and histopathologic parameters. METHODS: We included 113 women (mean age, 53 years; range, 29 to 72 years) with histopathology-confirmed ULMS from 2000 to 2012. Distribution of metastases was noted from imaging by two radiologists in consensus. Predictors of development of metastases were analyzed with univariate and multivariate analysis. Impact of various clinical and histopathologic parameters on survival was compared using Log-rank test and Cox proportional hazard regression model. RESULTS: Distant metastases were seen in 81.4% (92/113) of the patients after median interval of 7 months (interquartile range, 1 to 21). Lung was most common site of metastases (74%) followed by peritoneum (41%), bones (33%), and liver (27%). Local tumor recurrence was noted in 57 patients (50%), 51 of whom had distant metastases. Statistically significant correlation was noted between local recurrence and peritoneal metastases (p<0.001) and between lung and other common sites of hematogeneous metastases (p<0.05). Age, serosal involvement, local recurrence, and the International Federation of Gynecology and Obstetrics (FIGO) stage were predictive factors for metastases. At the time of reporting, 65% (74/113) of the patients have died; median survival was 45 months. Stage, local recurrence, and age were poor prognostic factors. CONCLUSION: ULMS metastasizes most frequently to lung, peritoneum, bone, and liver. Local recurrence was associated with peritoneal spread and lung metastases with other sites of hematogeneous metastases. Age, FIGO stage and local recurrence predicted metastatic disease and advanced stage, older age and local recurrence predicted poor outcome.

Small bowel obstruction in the emergency department: MDCT features of common and uncommon causes.

Small bowel obstruction is a common condition encountered by the radiologist in the emergency department. Though intestinal adhesions and obstructed hernias are the most common causes of acute small bowel obstruction, a variety of uncommon and rare conditions can cause acute and subacute bowel obstruction. Imaging plays a key role in the workup of bowel obstruction by identifying the cause, level, and degree of bowel obstruction. In this article, we present a comprehensive review of the multi-detector computed tomography features of common and uncommon causes of acute and subacute small bowel obstruction.