Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009676 (confusion)
 21,692 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Osteoclast-like giant cells (GC) may dominate the histologic pattern not only in conventional giant-cell tumor (GCT)--originating as a radiologically pure lytic, possibly trabeculated lesion especially within the epiphyses of long tubular bones (LB) and pelvic bones of adults--but also in many tumor-like lesions as well as in various benign and malignant bone tumors which may simulate each other. Although the mononuclear cells as well as the amount of collagene fibres don't differ significantly, these lesions can be distinguished by substantial differences concerning their site, radiomorphology and the patients age. The unique lesion which can be recognized by histology only is chondroblastoma--centered in epiphyseal regions as GCT, mostly in the 2nd decade--by its typical mononuclear cells independently of the typical chondroid matrix and calcifications. The brown tumor of hyperparathyreoidism is associated with elevated serum Ca and parathormon, which is not altered in the histologically identical giant cell granuloma. In contrast to GCT aneurysmal bone cyst prefers the metaphyseal area of LB and the posterior parts of vertebras in the 2nd decade. Metaphyseal fibrous defects occurring during growth period leave the epiphyses unaffected and display typical x-rays. Villondoular synovitis sometimes can produce osteolytic defects. GC-rich malignant tumors which present with clear cut atypia except some cases of GC-variants of osteosarcoma, are: Giant-cell rich osteosarcoma, the rare malignant GCT, giant-cell ("osteoclastic") sarcoma, MFH and GC-rich metastases of carcinomas. All of them occur in middle aged and older patients except osteosarcoma and don't affect the epiphyses primarily except malignant GCT. To avoid confusion in GC-lesions it is conditio sine qua non to take into account for diagnosis not only histology but especially radiomorphology as well as site of the lesion and patients age.
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PMID:[Differential diagnosis of giant cell tumor of bone]. 1009 27

Focal myxoid change is a well-recognized feature of solitary fibrous tumor (SFT), but to date, predominantly myxoid examples of SFT have not been reported. We describe seven cases of SFT in which stromal myxoid change affected 50% or more of the tumor examined, thus obscuring typical diagnostic features. Patients ranged in age from 35 to 68 years old (median, 45 yr), with an equal sex distribution. Tumor locations included pleura, orbit, and periparotid subcutaneous tissue, as well as four cases in deep soft tissue (two in the abdominal wall and one each in the chest wall and thigh). Myxoid areas were identified grossly in four cases. Histologically, the lesions were composed of bland spindle cells disposed haphazardly or with a lacy or reticulated appearance in a myxoid, richly vascularized stroma These myxoid areas were punctuated by small cellular aggregates in four cases, and areas showing diagnostic features of SFT were present in five of seven primary excision specimens. Atypical features suggestive of malignancy were not present in any of the cases. Immunohistochemically, all of the seven cases stained positively for CD34 and CD99 (013), and all were negative for smooth muscle actin, desmin, S-100 protein, epithelial membrane antigen, and pan-keratin. There were no recurrences or metastases reported in four patients with limited follow-up (median duration, 19 mo). Recognition of this uncommon morphologic subset of SFT is important because of possible confusion, particularly in small biopsy specimens, with a variety of myxoid spindle cell neoplasms with different biologic potential. These include low-grade fibromyxoid sarcoma, myxoid synovial sarcoma, malignant peripheral nerve sheath tumor, low-grade myxofibrosarcoma, myxoid liposarcoma, myxoid spindle cell lipoma, myxoid neurofibroma, and so-called "hemangiopericytoma."
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PMID:Myxoid solitary fibrous tumor: a study of seven cases with emphasis on differential diagnosis. 1034 83

A Phase I study of angiogenesis inhibitor TNP-470 was conducted in patients with advanced cancer. TNP-470 (25-235 mg/m2) was administered i.v. over 4 h once a week to patients who had solid tumors refractory to the best available treatment or with a high risk of recurrence and who had normal renal, hepatic, and hematological function and no evidence of coagulopathy. The aims of the study were to determine the maximum tolerated dose, dose-limiting toxicities (DLTs), and the pharmacokinetics of TNP-470 given on a once-weekly schedule. Thirty-six patients, ages 23-75 (median, 54 years), with an Eastern Cooperative Oncology Group performance status of 0-2 were treated. The number of patients at each dose level (mg/m2) were 6 (25), 3 (50), 3 (75), 3 (100), 3 (133), 12 (177), and 6 (235). The principal toxicities of TNP-470 were dizziness, lightheadedness, vertigo, ataxia, decrease in concentration and short-term memory, confusion, anxiety, and depression, which occurred at doses of 133, 177, and 235 mg/m2. Two patients treated at 235 mg/m2 experienced DLT in the form of grade III cerebellar neurotoxicity after 6 weeks of treatment. Overall, these neurological symptoms were dose-related, had an insidious onset, progressively worsened with treatment, and resolved completely within 2 weeks of stopping the drug. One patient with malignant melanoma had stabilization of the previously growing disease for 27 weeks while on the treatment. Two patients, one with adenocarcinoma of the colon and the other with a soft tissue sarcoma, had no clinically detectable disease but were at high risk for recurrence at the initiation of treatment and received 13 months and > 3 years of treatment, respectively, with no evidence of disease recurrence. The remaining patients had progression of their disease after 1-6 months of treatment. The mean plasma half-life (t(1/2)) of TNP-470 and its principal metabolite, AGM-1883, were extremely short (harmonic mean, t(1/2) of 2 and 6 min, respectively) with practically no drug detectable in the plasma by 60 min after the end of the infusion. MII, an inactive metabolite, had a considerably longer t(1/2) of approximately 2.6 h. Mean peak TNP-470 concentrations were > or = 400 ng/ml at doses > or = 177 mg/m2. On the basis of this study, the maximum tolerated dose of TNP-470 administered on a weekly schedule was 177 mg/m2 given i.v over 4 h. The principal DLT was neurotoxicity, which appeared to be dose-related and was completely reversible. On the basis of the short plasma t(1/2) of TNP-470, exploration of a prolonged i.v. infusion schedule is warranted.
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PMID:A Phase I and pharmacokinetic study of TNP-470 administered weekly to patients with advanced cancer. 1047 76

Endometrial stromal tumors are reviewed with emphasis on their wide morphologic spectrum and problems in differential diagnosis, highlighting issues that have received particular attention in the recent literature. These neoplasms are divided into two major categories--endometrial stromal nodules and endometrial stromal sarcomas--a distinction made on the basis of the lack of significant infiltration at the periphery of the former. The division of endometrial stromal sarcomas into low-grade and high-grade categories has fallen out of favor and the designation endometrial stromal sarcoma is now considered best restricted to neoplasms that were formally referred to as "low-grade" stromal sarcoma. Endometrial sarcomas without recognizable evidence of a definite endometrial stromal phenotype, designated poorly differentiated "endometrial sarcomas," are almost invariably high grade and often resemble the mesenchymal component of a malignant mullerian mixed tumor. Two features of endometrial stromal tumors that may cause confusion are smooth muscle differentiation and epithelial patterns. Cases in the former category often have a characteristic "starburst" pattern of collagen formation. The most common epithelial patterns resemble those seen in ovarian sex-cord stromal tumors. Much less common is endometrioid gland differentiation. Some endometrial stromal tumors have a prominent fibrous or myxoid appearance and the myxoid tumors should be distinguished from myxoid leiomyosarcoma. Other unusual features of endometrial stromal tumors are also discussed. Lesions in the differential diagnosis of uterine endometrial stromal neoplasms include highly cellular leiomyoma, cellular intravenous leiomyomatosis, adenomyosis with sparse glands, metastatic carcinoma, and lymphoma. Endometrial stromal sarcomas at extrauterine sites may be primary or metastatic from a uterine tumor, the latter sometimes being occult and difficult to definitively establish, particularly if there is a history of a remote hysterectomy for "leiomyomas." Endometrial stromal sarcomas of the ovary, whether primary or metastatic, may be difficult to distinguish from ovarian sex-cord stromal tumors. Extragenital endometrial stromal sarcomas may be confused with diverse lesions such as gastrointestinal stromal tumors, hemangiopericytoma, lymphangiomyomatosis, or mesenchymal cystic hamartoma of the lung. Immunohistochemistry may play a role in evaluating these tumors and in some instances establishing the diagnosis although conventional light microscopic analysis suffices in the majority of cases. The unusual tumor, the "uterine tumor resembling an ovarian sex-cord tumor," is also considered in this review as it is almost certainly of endometrial stromal derivation in many cases. These neoplasms may have a striking resemblance to granulosa cell tumors or Sertoli cell tumors, including those with a retiform pattern, and have recently been shown to be frequently inhibin positive.
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PMID:Endometrial stromal tumors: an update on a group of tumors with a protean phenotype. 1097 6

Lymphomas with predominant spindle-cell morphology have only been previously reported in small numbers; such lesions are potentially mistaken for sarcoma or other spindle-cell tumours. We describe a 73-year-old woman who presented with a tumour on the scalp of a few months' duration. Biopsy showed a B-cell lymphoma of follicle centre cell origin with a sarcomatoid appearance and a CD20+, CD10+, CD21+, bcl-6+ immunophenotype. This case highlights the very rare occurrence of spindle-cell B-cell lymphoma presenting in the skin. An awareness of this phenomenon is essential to avoid confusion with a variety of other cutaneous spindle-cell neoplasms and to enable a correct diagnosis to be made, thereby ensuring that appropriate treatment is initiated.
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PMID:Spindle-cell B-cell lymphoma presenting in the skin. 1153

CD31 (platelet endothelial adhesion molecule, PECAM-1) is generally regarded to be the most sensitive and specific endothelial marker in paraffin sections. We have recently encountered several cases in which intratumoral CD31-positive macrophages were misinterpreted as evidence of a vascular sarcoma. We therefore reviewed our last 1950 consultation cases with respect to cases in which CD31 immunostains were performed, to determine the frequency of CD31 expression in macrophages in formalin-fixed, paraffin-embedded tissue and how often the presence of these cells was a source of diagnostic confusion. CD31 immunohistochemistry had been performed on 59 of 1950 (3%) of cases. These 59 cases consisted of both vascular (20 cases) and nonvascular tumors (39 cases). CD31-positive macrophages were distinguished from endothelial or tumor cells by correlation with the morphologic features and the immunohistochemical staining pattern of the cells of interest. In no case was CD31 positivity seen in the lesional cells of a nonvascular tumor. CD31-positive macrophages were identified in 48 of 59 (81%) cases. CD31-positive macrophages were present in 34 of 39 (87%) nonvascular tumors. A vascular tumor was diagnosed or favored by the referring pathologist in 15 of these 39 cases (38%). In 14 of these 15 cases CD31 immunostains were performed by the referring pathologist; 13 (93%) showed CD31-positive macrophages. In 4 of these 14 cases (29%) the misdiagnosis of a vascular tumor was based primarily or in part on the misinterpretation of CD31-positive macrophages as tumor cells. In all cases with CD34 and CD68 immunostains, the CD31-positive macrophages were CD34 negative and CD68 positive. We conclude that CD31 expression is very common in macrophages. Misinterpretation of CD31-positive macrophages as tumor cells may result in the erroneous diagnosis of a primary vascular neoplasm. Recognition of the characteristic granular, membranous pattern of CD31 expression in macrophages and careful distinction from tumor cells should allow the accurate interpretation of CD31 immunohistochemistry in possible vascular neoplasms. CD31 may also be useful as a nonlysosomal marker of macrophages in formalin-fixed, paraffin-embedded sections.
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PMID:CD31 expression in intratumoral macrophages: a potential diagnostic pitfall. 1236 57

Histiocytic sarcoma (HS) is a rare disease, and there has been much confusion concerning the diagnostic criteria for this entity. Since immunohistochemical and cytogenetic techniques have become more universally available, many cases initially diagnosed as histiocytic sarcoma have been reclassified as other diseases. We describe a case of HS that presented as a single mass lesion in left occipital lobe. At autopsy the tumor also involved the meninges as a thick exudate. Histologic examination showed numerous large pleomorphic malignant cells with areas of necrosis, numerous neutrophils, and phagocytosis by tumor cells. Immunohistochemically, the tumor cells stained positively with antibodies directed against most histiocytic markers and did not stain with antibodies directed against myeloid markers, dendritic markers, CD30, ALK1, or other lymphoid markers. Molecular cytogenetic analysis showed no rearrangement [i.e. t(2;5) translocation or other variant] by fluorescence in situ hybridization. The T-cell receptor-gamma chain by multiplex polymerase chain reaction showed a polyclonal pattern. No heavy or light chain gene rearrangements were found. To our knowledge, this is the first reported autopsy case of this rare entity primarily involving the brain and meninges.
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PMID:Histiocytic sarcoma involving the central nervous system: clinical, immunohistochemical, and molecular genetic studies of a case with review of the literature. 1254 75

Myxofibrosarcoma (myxoid malignant fibrous histiocytoma) is one of the most common fibroblastic sarcomas in the older patient, where it can sometimes present with anatomically deceptive boundaries. Myxofibrosarcoma is now fully characterized as a distinctive and definable pathologic entity. Clinically there is a tendency for predominantly subcutaneous, multinodular, diffusely infiltrative growth, which may extend to the overlying dermis and present as a cutaneous lesion. Histologically myxofibrosarcoma comprises a spectrum ranging from hypocellular low-grade myxoid to high-grade pleomorphic sarcoma. We report herein 6 cases of myxofibrosarcoma each with dermatological presentation as a cutaneous nodule. The dermal component in each of the lesions was low- to intermediate-grade and predominantly myxoid resulting in confusion with benign myxoid neoplasms in small biopsy specimens. The purpose of this series is to focus the attention of workers in dermatology on a subject rarely discussed in dermatopathology literature: the cutaneous presentation of myxofibrosarcoma and the potential for clinical and histologic misinterpretation, as benign dermal lesions.
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PMID:Myxofibrosarcoma presenting in the skin: clinicopathological features and differential diagnosis with cutaneous myxoid neoplasms. 1287 84

Gossypiboma, an iatrogenic mass lesion caused by a retained surgical sponge is an extremely rare event following musculoskeletal procedures. This entity is therefore a very unusual experience and can create considerable confusion. Unsuspecting surgeons may thus be caught out by this unlikely presentation. We present our experience with a recurrent gossypiboma in the thigh occurring several years after surgical evacuation of a similar gossypiboma from the same anatomic location with interval resolution of symptoms. The purpose of this case report is to highlight the possibility of a "recurrent" soft tissue mass occurring for reasons other than a neoplasm. In the absence of a definitive biopsy diagnosis of tumor in patients who have undergone prior surgical procedures in that area, it may be more prudent to adopt a conservative surgical resection rather than a conventional radical resection as warranted by the dramatic clinical presentation mimicking a soft tissue sarcoma.
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PMID:Recurrent gossypiboma in the thigh. 1709 9

Availability of KIT tyrosine kinase inhibitors for specific treatment of GISTs has magnified the importance of accurate differential diagnosis of GIST from other tumors occurring in the GI tract and abdomen. The general problems in this distinction include histological mimicry of other mesenchymal tumors with GIST, occasional KIT-negativity of GIST, and KIT-positivity of non-GISTs. Up to 5% to 10% gastric GISTs and <2% of intestinal GISTs can be KIT-negative. The identification of these tumors as GISTs is based on knowledge of the spectrum of GIST morphology, and can be supported by molecular diagnosis of KIT and PDGFRA mutations (the latter pertain to gastric tumors). True smooth muscle tumors (rare in GI tract except in esophagus and colon) can be separated from GISTs by the eosinophilic tinctorial quality of tumor cells, positivity for smooth muscle markers, and negativity for KIT. Desmoids can form large GIST-like masses, but are composed of spindled or stellate-shaped cells in a densely collagenous stroma. Negativity for KIT and nuclear positivity for beta-catenin are differentiating features. GI schwannomas, melanoma, and rare primary clear cell sarcoma are S100-positive, usually with characteristic histology. The latter two can be KIT-positive. KIT-positive non-GISTs include some sarcomas, especially angiosarcoma and Ewing sarcoma, extramedullary myeloid tumor, seminoma, and a few carcinomas, notably small cell carcinoma of lung. Spurious KIT-positivity, seen with some polyclonal KIT antibodies, has been a source of confusion leading to probable false-positive results in fibroblastic tumors and occasional other sarcomas, such as leiomyosarcomas. Integration of histological features with carefully standardized immunohistochemistry, supported by KIT and PDGFRA mutation analysis, is the cornerstone of state-of-the art differential diagnosis of GIST. To comprehensively capture all GISTs, KIT immunostains should be performed on all unclassified epithelioid and mesenchymal tumors of the abdomen. This is a US government work. There are no restrictions on its use.
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PMID:Gastrointestinal stromal tumors: differential diagnosis. 1719 24


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