Tophaceous pseudogout in a 12-year-old dog, with a review of applicable laboratory tests.

Pseudogout, also known as calcium pyrophosphate dihydrate (CPPD) deposition disease or chondrocalcinosis, is caused by crystalline deposits of CPPD within the extracellular matrix of articular hyaline cartilage and fibrocartilage, and within articular and periarticular connective tissue. Using a variety of laboratory techniques, we diagnosed pseudogout in the right hindlimb digit V of a 12-y-old Standard Poodle. Histologically, the joint, bone, tendon, and dermis were expanded and effaced by masses of mineralized, rhomboid crystals surrounded by macrophages, multinucleate giant cells, fibrous connective tissue, and chondroid and osseous matrix.

Dysplastic Lipoma: A Distinctive Atypical Lipomatous Neoplasm With Anisocytosis, Focal Nuclear Atypia, p53 Overexpression, and a Lack of MDM2 Gene Amplification by FISH; A Report of 66 Cases Demonstrating Occasional Multifocality and a Rare Association With Retinoblastoma.

In our routine and consultative pathology practices, we have repeatedly encountered an unusual subcutaneous fatty tumor with notable anisocytosis, single-cell fat necrosis, and patchy, often mild, adipocytic nuclear atypia. Because of the focal atypia, consultative cases have most often been received with concern for a diagnosis of atypical lipomatous tumor. Similar tumors have been described in small series under the designations "subcutaneous minimally atypical lipomatous tumors" and "anisometric cell lipoma.

Sox10--a marker for not only schwannian and melanocytic neoplasms but also myoepithelial cell tumors of soft tissue: a systematic analysis of 5134 tumors.

Sox10 transcription factor is expressed in schwannian and melanocytic lineages and is important in their development and can be used as a marker for corresponding tumors. In addition, it has been reported in subsets of myoepithelial/basal cell epithelial neoplasms, but its expression remains incompletely characterized. In this study, we examined Sox10 expression in 5134 human neoplasms spanning a wide spectrum of neuroectodermal, mesenchymal, lymphoid, and epithelial tumors.

Myxoinflammatory fibroblastic sarcoma: a clinicopathologic analysis of 104 cases, with emphasis on predictors of outcome.

In this study, we examine the clinicopathologic features of 104 cases of myxoinflammatory fibroblastic sarcoma (MIFS), a low-grade, inflammatory fibromyxoid tumor with a predilection to distal extremity soft tissue, and attempt to identify factors predictive of aggressive behavior. The study cohort consisted of 49 male and 55 female patients ranging in age from 17 to 83 (mean, 42; median, 39) years. The tumor arose primarily on the dorsal aspect of the distal extremities as a solitary and usually painless mass.

ERG expression in epithelioid sarcoma: a diagnostic pitfall.

ERG transcription factor is constitutively expressed in endothelial cells. Because benign and malignant vascular endothelia retain the ERG expression, ERG is considered a useful marker for angiosarcomas and related tumors. ERG is also expressed in a subset of prostate carcinomas and Ewing sarcomas due to ERG-involved translocations; therefore, this marker is also of high interest in the study of these malignancies.

Inguinal smooth muscle tumors in women-a dichotomous group consisting of Müllerian-type leiomyomas and soft tissue leiomyosarcomas: an analysis of 55 cases.

Assessment of the biological potential of smooth muscle tumors can be difficult and depends primarily on tumor site, stage, and histologic parameters. In this study, we examined the clinicopathologic and immunohistochemical features of 55 noncutaneous inguinal smooth muscle tumors of women (age range, 20 to 82 y; median, 57 y). Histologically, 23 tumors were considered as leiomyomas.

Imaging characteristics of tenosynovial and bursal chondromatosis.

Objectives: Our purpose was to identify imaging characteristics of tenosynovial and bursal chondromatosis.

Materials And Methods: We retrospectively reviewed 25 pathologically confirmed cases of tenosynovial (n = 21) or bursal chondromatosis (n = 4). Patient demographics and clinical presentation were reviewed.

Leiomyosarcoma of the inferior vena cava: clinicopathologic study of 40 cases.

This report details the clinicopathologic features and follow-up data on 40 cases of inferior vena cava leiomyosarcoma, a rare sarcoma with a poor prognosis. Study cohort consisted of 31 females and 9 males (mean age, 53 y), whose material was accessioned to the Armed Forces Institute of Pathology between 1976 and 2008. Inferior vena cava leiomyosarcomas ranged in size from 3.

Ocular perivascular epithelioid cell tumor: report of 2 cases with distinct clinical presentations.

Perivascular epithelioid cell tumors comprise a rare and recently described family of neoplasms that characteristically coexpress melanocytic and myoid markers. We describe the clinicopathologic features of 2 ocular cases. Case 1 occurred in a 26-year-old woman with a recurrent left upper eyelid tumor, and case 2 was diagnosed in a 7-year-old boy with a left ciliary body mass.

Ossifying fibromyxoid tumor of soft parts--a clinicopathologic and immunohistochemical study of 104 cases with long-term follow-up and a critical review of the literature.

Ossifying fibromyxoid tumor (OFT) is a unique soft tissue tumor of uncertain histogenesis. The majority of reported cases (approximately 220) have pursued a benign clinical course. However, recent literature has emphasized the existence of morphologically atypical and clinically malignant examples of this tumor and proposed guidelines for assessment of biologic potential.

Neurothekeoma: an analysis of 178 tumors with detailed immunohistochemical data and long-term patient follow-up information.

This report describes the clinicopathologic findings in 176 patients who presented with 178 tumors currently referred to as neurothekeomas. Our study group included 64 males and 112 females, ranging from 20 months to 85 years old at the time of their first surgical procedure (median age: 17 y). Twenty-four percent of patients were or=30 years of age at initial diagnosis.

Calcareous lesions of the distal extremities resembling tumoral calcinosis (tumoral calcinosislike lesions): clinicopathologic study of 43 cases emphasizing a pathogenesis-based approach to classification.

Herein, we analyze the clinicopathologic features of 46 distal extremity lesions that have histologic features similar to conventional tumoral calcinosis (tumoral calcinosislike; TC-L). The study included 31 females and 12 males (whites:non-whites>3:1) ranging in age from 1 to 91 (mean, 39; median, 42) years. The lesions presented in fingers (n=20), feet (n=10), wrist (n=6), hands (5), toes (n=4), and ankle (n=1) were solitary in all but 5 patients and ranged in size from 0.

Sclerotic (fibroma-like) lipoma: a distinctive lipoma variant with a predilection for the distal extremities.

This report details the clinicopathologic and immunohistochemical findings identified in 21 cases of a fibrosclerotic variant of lipoma from acral sites that is frequently misdiagnosed as a fibromatous (nonlipogenic) process. The study includes 12 males and 9 females; aged 7 to 72 (mean and median, 39). The patients presented with solitary, mostly asymptomatic, masses that ranged from 0.

Minute synovial sarcomas of the hands and feet: a clinicopathologic study of 21 tumors less than 1 cm.

Synovial sarcoma, one of the most common types of soft tissue sarcomas, usually presents in the proximal or middle portions of the extremities, often as a large mass with an aggressive clinical behavior. Gland-forming biphasic and spindle cell fibrous monophasic tumors are the most common subtypes. In this study, we evaluated 21 minute synovial sarcomas, <1 cm in diameter, from the hands and feet.

Reticulohistiocytoma (solitary epithelioid histiocytoma): a clinicopathologic and immunohistochemical study of 44 cases.

Reticulohistiocytoma and multicentric reticulohistiocytosis are designations for uncommon, incompletely characterized histiocytic proliferations of the skin or soft tissues. In this study, we analyzed a uniform group of 44 lesions composed of epithelioid histiocytes, comprising a subset of lesions originally designated as reticulohistiocytoma, and propose designating them as "solitary epithelioid histiocytoma" (SEH), in line with the recently published classification proposal for histiocytic disorders. There were 26 males and 18 females with a median age of 35 years (range, 2.

Evaluation of biological potential of smooth muscle tumours.

Smooth muscle tumours (SMTs) have been traditionally divided into benign leiomyomas (LM) and malignant leiomyosarcomas (LMS) based on cytological atypia, mitotic activity and other criteria. In most instances, this dichotomous approach works, but in some instances the biological potential cannot be determined with certainty. This is often because some, but not all criteria for malignancy have been met or because the tumours are occurring in unusual settings for which there are sparse substantive data.

Gastrointestinal stromal tumors in patients with neurofibromatosis 1: a clinicopathologic and molecular genetic study of 45 cases.

Gastrointestinal stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, most commonly occur sporadically, but there seems to be some increased tendency for these tumors to develop in patients with neurofibromatosis 1 (NF1). The clinicopathologic profile, KIT, and PDGFRA mutation status and long-term prognosis of patients with GIST in NF1 are incompletely characterized. In this study, we analyzed 45 patients who had NF1 and GIST.

Nerve sheath myxoma: a clinicopathologic and immunohistochemical analysis of 57 morphologically distinctive, S-100 protein- and GFAP-positive, myxoid peripheral nerve sheath tumors with a predilection for the extremities and a high local recurrence rate.

This report describes the clinicopathologic findings in 57 cases of nerve sheath myxoma. Our study group included 34 males and 23 females, ranging from 8 to 72 years of age at the time of their first surgical procedure (mean, 36 years; median, 34 years). The patients typically presented with solitary, superficial, multinodular masses in the 0.

Palmar-plantar fibromatosis in children and preadolescents: a clinicopathologic study of 56 cases with newly recognized demographics and extended follow-up information.

Palmar-plantar fibromatosis, the most common type of fibromatosis, is well recognized in the adult population, but many clinicians and pathologists are unfamiliar with the fact that children may also be affected by this process. This report describes the clinicopathologic findings in 56 cases of palmar-plantar fibromatosis in children and preadolescents. Our study group included 19 males and 37 females, ranging from 2 to 12 years of age at the time of their first surgical procedure (median age, 9 years).

Granular cell tumor of the penis: clinicopathologic evaluation of 9 cases.

The occurrence of granular cell tumor (GCT) in penile tissue is very rare, with only 9 examples reported to date in the English-language literature. Herein, we describe the clinicopathologic and immunohistochemical findings in 9 additional cases. The patients ranged in age from 20 to 60 years (mean, 42 years; median, 40 years) at time of diagnosis.

Villonodular synovitis (PVNS) of the spine.

Objective: To describe the imaging features of spinal pigmented villonodular synovitis (PVNS).

Design And Patients: We retrospectively reviewed 15 cases of pathologically proven spinal PVNS. Patient demographics and clinical presentation were reviewed.

Benign epithelioid peripheral nerve sheath tumors of the soft tissues: clinicopathologic spectrum of 33 cases.

Benign epithelioid peripheral nerve sheath tumors (BEPNSTs) have not been fully characterized, and their relationship to conventional schwannoma and neurofibroma has not been satisfactorily established. Herein, we detail the clinicopathologic features of 33 examples of BEPNST. The study included 22 females and 11 males ranging in age from 2 to 68 years (median, 31.