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M Kyriakos

Publications and source records attributed to M Kyriakos.

At least 19 recordsLinked to original sources

Malignant giant-cell tumor of the parietal bone: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Giant-cell tumors (GCTs) are primary bone tumors that involve long bones in 75 to 90% of patients. They seldom develop in the cranium and are very rare in patients older than 60 years of age. A GCT rarely occurs with Paget's disease; when it does, however, it is most commonly associated with the polyostotic form and tends to involve the craniofacial bones. Pagetic GCTs are less aggressive than GCTs that are not associated with Paget's disease. CLINICAL PRESENTATION: We report the case of an 81-year-old woman with a painless left parietal mass and asymptomatic monostotic parietal Paget's disease. INTERVENTION: Surgical resection was performed, and histological examination of the lesion demonstrated Paget's disease with a malignant GCT. An incidental, low-grade, small-cell lymphocytic lymphoma also was noted. The patient experienced local recurrence of the malignant GCT and eventually died after developing pulmonary metastases of the malignant GCT. CONCLUSION: This case is the first reported example of a patient with a malignant GCT of the cranium associated with monostotic Paget's disease. It provides evidence that not all pagetic GCTs in the cranium are benign, as has been reported.

Aged↗

Imaging findings in pseudocystic osteosarcoma.

OBJECTIVE: Our purpose was to describe four female patients with osteosarcoma whose clinical and imaging findings primarily suggested either simple or aneurysmal bone cyst. All lesions were osteolytic, intracompartmental, and expanded bone without periosteal reaction. None of the patients presented during the peak age incidence for osteosarcoma. From imaging to histologic diagnosis, the discovery of osteosarcoma ranged from 1 week to 3 years. CONCLUSION: Atypical osteosarcoma may rarely mimic simple or aneurysmal bone cyst radiologically and may show a nonmalignant rate of growth. It may be more frequently encountered in females and may not present during the peak age incidence for osteosarcoma. Microscopically, the tumors were not cystic, necrotic, or telangiectatic but were conventional osteosarcoma and osteoclast-rich osteosarcoma.

Adult↗

Synovial chondromatosis in a facet joint of a cervical vertebra.

STUDY DESIGN: A case report of a cervical facet joint synovial chondromatosis. OBJECTIVES: To correlate the radiologic and histologic features of vertebral synovial chondromatosis with review of the literature. SUMMARY OF BACKGROUND DATA: Only two previous cases of vertebral facet joint synovial chondromatosis were found in a review of the English language medical literature. METHODS: A 39-year-old woman had severe cervical pain associated with neurologic signs and symptoms in the left upper extremity. Computed tomographic and magnetic resonance imaging studies were performed. RESULTS: Imaging studies showed lytic defects in the laminae of C3 and C4, with intermediate T1 and high T2 signal intensities. The diagnostic impression was that of a lymphangioma or synovial cyst. A laminectomy showed synovial tissue in both the C3-C4 facet joint and the lamina bone. Histologic examination disclosed synovial chondromatosis. CONCLUSIONS: Synovial chondromatosis of the vertebral spine is quite rare, this being only the third reported example. Direct invasion of the cancellous bone, as in this case, also is a very uncommon feature of chondromatosis. It is emphasized that when radiologic studies demonstrate a lesion with cartilaginous characteristics within or juxtaposed to a joint, synovial chondromatosis, despite its rarity, should be included in the differential diagnosis, regardless of the anatomic site.

Adult↗

Solitary skeletal hemangioma of the extremities.

OBJECTIVE: To report the clinicopathologic features of solitary skeletal hemangioma of the extremities and to review previous cases in the English language medical literature. PATIENTS: In addition to five of our own cases, 34 literature cases with substantial and 75 with partial clinicopathologic information were found. RESULTS: Our patients, three men and two women, ranged in age from 37 to 83 years (mean 65.6 years). The lesion was an incidental radiologic finding in two patients, while three were symptomatic. In no case was a correct preoperative radiologic diagnosis made, a malignant process being considered as a possibility in all. The hemangiomas were medullary; two involved a metacarpal, two the fibula, and one the humerus. In contrast, previously reported patients were younger (mean age 32 years), predominantly female (60%), and symptomatic in over 90% of cases. The lesion is rare in those younger than age 10 years or older than age 60 years. As in our patients, the long bones are most frequently involved (75%), with the diaphysis or metadiaphysis, as in four of our patients, the most common locations. Although 20% of cases occur in the hands or feet, metacarpal involvement is rare. Medullary origin, as in all of our cases, is most frequent, but 45% of cases are either periosteal (33%) or intracortical (12%). In the literature, cavernous hemangioma is the most frequent type. Three of our hemangiomas were cavernous, one capillary, and one venous, the latter being rarely reported in extremity bones. CONCLUSIONS: Due to the diversity of radiologic patterns produced by skeletal hemangioma, a correct preoperative diagnosis is rarely made. Almost all patients do well, even those with less than complete removal of the lesion; local recurrence is rare. All of our patients were well following either therapeutic or simple diagnostic procedures. Due to the destructive nature of some biopsy procedures, the histologic diagnosis of hemangioma may at times also be problematic.

Adult↗

Malignant peripheral nerve sheath tumors with t(X;18). A pathologic and molecular genetic study.

Spindle cell sarcomas often present the surgical pathologist with a considerable diagnostic challenge. Malignant peripheral nerve sheath tumor, leiomyosarcoma, fibrosarcoma, and monophasic synovial sarcoma may all appear similar histologically. The application of ancillary diagnostic modalities, such as immunohistochemistry and electron microscopy, may be helpful in the differentiation of these tumors, but in cases in which these adjunctive techniques fail to demonstrate any more definitive evidence of differentiation, tumor categorization may remain difficult. Cytogenetic and molecular genetic characterization of tumors have provided the basis for the application of molecular assays as the newest components of the diagnostic armamentarium. Because the chromosomal translocation t(X;18) has been observed repeatedly in many synovial sarcomas, it has been heralded as a diagnostic hallmark of synovial sarcoma. To formally test the specificity of this translocation for the diagnosis of synovial sarcoma, RNA extracted from formalin-fixed, paraffin-embedded tissue from a variety of soft tissue and spindle cell tumors was evaluated for the presence of t(X;18) by reverse transcriptase-polymerase chain reaction. Although 85% of the synovial sarcomas studied demonstrated t(X;18), 75% of the malignant peripheral nerve sheath tumors in our cohort also demonstrated this translocation. We conclude that the translocation t(X;18) is not specific to synovial sarcoma and discuss the implications of the demonstration of t(X;18) in a majority of malignant peripheral nerve sheath tumors.

Adolescent↗

Malignant peripheral nerve sheath tumors with t(X;18). A pathologic and molecular genetic study.

Spindle cell sarcomas often present the surgical pathologist with a considerable diagnostic challenge. Malignant peripheral nerve sheath tumor, leiomyosarcoma, fibrosarcoma, and monophasic synovial sarcoma may all appear similar histologically. The application of ancillary diagnostic modalities, such as immunohistochemistry and electron microscopy, may be helpful in the differentiation of these tumors, but in cases in which these adjunctive techniques fail to demonstrate any more definitive evidence of differentiation, tumor categorization may remain difficult. Cytogenetic and molecular genetic characterization of tumors have provided the basis for the application of molecular assays as the newest components of the diagnostic armamentarium. Because the chromosomal translocation t(X;18) has been observed repeatedly in many synovial sarcomas, it has been heralded as a diagnostic hallmark of synovial sarcoma. To formally test the specificity of this translocation for the diagnosis of synovial sarcoma, RNA extracted from formalin-fixed, paraffin-embedded tissue from a variety of soft tissue and spindle cell tumors was evaluated for the presence of t(X;18) by reverse transcriptase-polymerase chain reaction. Although 85% of the synovial sarcomas studied demonstrated t(X;18), 75% of the malignant peripheral nerve sheath tumors in our cohort also demonstrated this translocation. We conclude that the translocation t(X;18) is not specific to synovial sarcoma and discuss the implications of the demonstration of t(X;18) in a majority of malignant peripheral nerve sheath tumors.

Adolescent↗

Posttraumatic fibro-osseous lesion of rib.

Eleven cases are described of an unusual, benign, fibro-osseous lesion of rib previously reported under a variety of designations, including painless fibro-osseous lesion resembling osteoid osteoma, symmetrical fibro-osseous dysplasia, focal Erdheim-Chester disease, and fibro-osseous pseudotumor. All patients were adults, most of whom were asymptomatic, the lesion discovered by bone scans done to rule out metastatic disease. A single rib was involved in eight patients and multiple ribs in three. A roentgenographic abnormality was apparent in only five patients. Histologically, all lesions showed a bland fibrous stroma in which resided an anastomosing network of bone trabeculae, having a zonal pattern of maturation from metaplastic woven to mature lamellar bone, with or without an associated xanthomatous component. Seven patients had a history of previous trauma, three with fractured ribs. Considering the relative infrequency of solitary rib lesions attributable to metastatic disease, it is proposed that in most cases there is no need for a diagnostic rib resection for these incidentally discovered, posttraumatic reparative lesions.

Aged↗

Interleukin-12 promotes activation of effector cells that induce a severe destructive granulomatous form of murine experimental autoimmune thyroiditis.

Granulomatous inflammatory lesions are a major histopathological feature of a wide spectrum of human infectious and autoimmune diseases. Experimental autoimmune thyroiditis (EAT) with granulomatous histopathological features can be induced by mouse thyroglobulin (MTg)-sensitized spleen cells activated in vitro with MTg and anti-interleukin-2 receptor (anti-IL-2R), anti-IL-2, or anti-interferon-gamma (anti-IFN-gamma) monoclonal antibody (MAb). These studies suggested that IFN-gamma-producing T cells requiring IL-2 for growth may negatively regulate activation of granulomatous EAT effector cells. As IL-12 promotes activation of IFN-gamma-producing Th1 cells, the present study was undertaken to determine the role of IL-12 in activation of effector cells for granulomatous EAT. MTg-sensitized cells activated in vitro with MTg, anti-IL2R MAb, and IL-12 induced severe, destructive granulomatous thyroiditis with neutrophil inflammation, fibrin deposition, and necrosis. Many glands ultimately underwent atrophy and became fibrotic; some also showed fibrinoid necrosis and a mixed inflammatory cell infiltration of blood vessel walls indicative of a necrotizing vasculitis. Induction of severe granulomatous EAT by IL-12 required MTg in vitro and was unrelated to the IL-12-induced increase in IFN-gamma production. IL-12 markedly increased IFN-gamma production but did not induce a shift to a Th1-dominant phenotype, as other Th1 and Th2 cytokines were generally unaffected and both Th1 and Th2 cytokines were expressed in recipient thyroids. Addition of IL-12 or neutralization by anti-IL-12 at various times indicated that IL-12 exerted its primary effects in the final 24 hours of the 72-hour culture and was not required in recipient mice. Cells cultured with anti-IL-12, MTg, and anti-IL2R MAb transferred mild lymphocytic EAT but little or no granulomatous EAT. Thus, IL-12 profoundly regulates the in vitro activation of effector cells that induce histologically distinct autoimmune inflammatory lesions in the thyroid.

Animals↗

Calcium carbonate apatite deposition in the cervical spine with associated vertebral destruction. Case report.

This 52-year-old woman developed crystal deposition disease involving the cervical vertebrae. She presented with symptomatic spinal cord compression secondary to extensive calcified lesions in the posterior elements of the cervical spine. Surgical decompression with posterior fusion was performed. Histological examination showed hardened deposits of calcium carbonate involving the soft tissue, and dissolution of the vertebral bone trabeculae. There was no inflammatory response to these deposits. One year postoperatively the patient developed severe pulmonary disease associated with the collagen-vascular disorder, scleroderma (calcinosis, Raynaud's phenomenon, esophageal hypomotility, sclerodactyly, and telangiectasia [CREST] syndrome). Calcium carbonate deposition disease represents an unusual clinical entity that is possibly associated with scleroderma or other collagen-vascular diseases, and it is distinct from ligamentum flavum calcification, calcium pyrophosphate deposition disease, and hydroxyapatite deposition disease.

Apatites↗

Painless osteoid osteoma of the rib in an adult. A case report and a review of the literature.

BACKGROUND: An asymptomatic rib lesion was discovered by means of a bone scan obtained during the clinical evaluation of an adult man with biopsy proven prostate adenocarcinoma. Clinically and radiologically considered to be a metastatic focus, on resection it proved to be an osteoid osteoma (OO). METHODS: A review of the English medical literature on OO was conducted with emphasis on the occurrence in older patients, costal location, and the absence of pain. RESULTS: OO in patients older than age 50 years is rare (1% - 2% of cases). Only 18 cases of painless OO were found. Of these, 8 (44%) occurred in the phalanges, and 3 (17%) in the cranial-facial bones, both uncommon sites for OO; only 7 (39%) arose in the long bones, the most common site for conventional OO. A disproportionate number of these patients (44%) were younger than age five years, a rarity for OO. Fourteen reported examples of costal OO were found, all of which were associated with pain. The possible mechanisms involved in the production of pain, including analysis of the effect of its site of origin and the presence of nerve fibers, is reviewed. CONCLUSIONS: Costal OO is distinguished from osteoblastoma and from what has been described as painless fibro-osseous lesion of the rib. The infrequency of metastases as a cause of solitary rib lesion is emphasized.

Adolescent↗

Giant-cell tumor of the distal phalanx of the hand in a child.

Giant-cell tumor of bone in the distal phalanx is rare, as is its clinical occurrence in children. A case of a 10-year-old girl with giant-cell tumor in the distal phalanx of the left thumb is reported, and a literature review of phalangeal giant-cell tumor of the hand is presented. The tumor was curetted, and after 2.5 years there was no recurrence.

Bone Neoplasms↗

Differential requirement for autoantibody-producing B cells for induction of lymphocytic versus granulomatous experimental autoimmune thyroiditis.

Mouse thyroglobulin (MTg)-sensitized spleen cells activated in vitro with MTG transfer experimental autoimmune thyroiditis (EAT) in which the thyroid cellular infiltrate consists primarily of mononuclear cells (lymphocytic EAT). Addition of anti-IL2R antibody to cultures with MTg leads to activation of cells that induce granulomatous EAT, accompanied by high serum anti-MTg autoantibody responses, in recipient mice. CD4+ T cells are required to induce both forms of EAT; whether B cells and/or autoantibodies produced by MTg-sensitized B cells also contribute to disease severity or the type of thyroid histopathology is unknown. In our study, B cells and autoantibody responses produced in recipient mice were reduced either by column removal of B cells from donor spleen cells or by treatment of recipient mice with anti-I-AK mAb at the time of cell transfer. These maneuvers only slightly reduced the severity of lymphocytic EAT but markedly reduced the severity and incidence of granulomatous EAT developing in recipient mice. Delaying the initiation of anti-I-AK treatment until 6 days after cell transfer was less effective in reducing anti-MTg autoantibody responses or granulomatous EAT. These studies all suggested that anti-MTg autoantibodies were required for development of granulomatous but not lymphocytic EAT. However anti-I-AK-treated recipients receiving injections of anti-MTg antibody or having serum antibody induced by prior immunization with MTg and LPS also developed less severe granulomatous EAT than controls. These results suggest that sensitized CD4+ T cells and circulating anti-MTg autoantibody are not sufficient for development of granulomatous thyroid lesions. It is possible that antibodies having a unique function or specificity are produced in mice developing granulomatous EAT or thyroid-infiltrating B cells may directly contribute to the granulomatous inflammatory response.

Animals↗

Regulation of the induction and resolution of granulomatous experimental autoimmune thyroiditis in mice by CD8+ T cells.

Mouse thyroglobulin (MTg)--sensitized spleen cells activated in vitro with MTg induce experimental autoimmune thyroiditis (EAT) in which the thyroid cellular infiltrate consists primarily of mononuclear cells (lymphocytic EAT). Cells cultured with MTg plus anti-IL2R antibody induce EAT having a granulomatous histopathology. CD4+ T cells are required to induce both forms of EAT. The potential contribution of CD8+ T cells in the pathology of lymphocytic vs granulomatous EAT was addressed using anti-CD8 mAb to deplete CD8+ T cells from donor or recipient mice. Depletion of donor CD8+ T cells had little effect on EAT severity induced by cells cultured with MTg or MTg plus anti-IL2R mAb. However, recipients of CD8-depleted cells activated with MTg induced granulomatous EAT whereas cells from untreated donors activated with MTg alone induced lymphocytic EAT. Similar results were obtained when anti-CD8 mAb was added to cultures to block activation of CD8+ T cells. Injection of anti-CD8 mAb into recipient mice slightly increased the severity of EAT induced by cells cultured with MTg or MTg and anti-IL2R mAb when EAT was assessed 19-20 days after cell transfer. Cells cultured with MTg alone induced mild granulomatous EAT in most anti-CD8-treated recipients. When thyroids of mice which had granulomatous EAT on Day 19 were examined 47 or 60 days after cell transfer, the granulomatous inflammatory response in untreated recipients had almost completely resolved. In contrast, granulomatous EAT persisted and often became more severe in anti-CD8-treated recipients. Anti-CD8 treatment did not influence lymphocytic EAT assessed late after cell transfer. These results indicate that CD8+ T cells are required for the resolution of granulomatous EAT.

Animals↗

Plasma cell tumors with calcified amyloid deposition mistaken for chondrosarcoma.

PURPOSE: To report cases of plasmacytoma with a radiologic appearance simulating that of chondrosarcoma. MATERIALS AND METHODS: The authors describe four cases of plasma cell tumors with scattered foci of calcification within their matrix, causing them to resemble chondrosarcoma radiographically. Histologic examination was performed in three of these cases. RESULTS: Biopsy specimens demonstrated that the calcification in these tumors was contained in areas of amyloid deposition. Although amyloid formation in association with plasma cell dyscrasias is well known, sufficient calcification within the amyloid to become radiographically identifiable has only rarely been reported. CONCLUSION: Calcification in amyloid produced by plasma cell tumors may at times simulate the appearance of chondrosarcoma.

Amyloid↗

Bone infarct-associated osteosarcoma.

Reported is a patient with an osteosarcoma arising in a medullary infarct of the humerus. Infarct-associated sarcoma (IAS) of bone is rare. In a collective review of 50 cases reported in the medical literature, only 37 were fully documented. Including our patient, 26 men and 12 women, ranging in age from 18 to 82 years (mean, 53.4 years) have been reported. Black patients appeared to be disproportionately represented, accounting for 36% of the group. In most patients, there was no known cause for the infarct, whereas in the remainder, the most common underlying condition was a prior dysbaric event or alcoholism. Approximately 75% of the patients had multiple bone infarcts. The femur was involved in 21 patients, the tibia in 14, the humerus in 2, and the radius in 1. Among 40 sarcomas in these patients, 7 (18.4%) were osteosarcomas, and 29 (72.5%) were malignant fibrous histiocytomas. The survival rate in patients with IAS is poor: 5 of the 7 patients with osteosarcoma (71%) and 20 of the 31 other patients (65%) died of tumor. Eight patients are alive and well, all for longer than 5 years.

Aged↗

Induction of granulomatous experimental autoimmune thyroiditis in mice with in vitro activated effector T cells and anti-IFN-gamma antibody.

Experimental autoimmune thyroiditis (EAT) can be induced in mice after the transfer of mouse thyroglobulin (MTg)-sensitized donor spleen cells that have been activated in vitro with MTg. CD4+ T cells are required for the transfer of EAT in this model. Because CD4+ T cells produce various lymphokines, such as IFN-gamma, that may be involved in the activation or regulation of the immune response to MTg and the development of EAT, the present study was undertaken to determine whether a neutralizing mAb to IFN-gamma could modulate the induction or expression of EAT. The anti-IFN-gamma mAb XMG-1.2 had no effect on sensitization of donor cells. However, addition of XMG-1.2 mAb during in vitro activation of MTg-primed spleen cells resulted in more severe EAT in recipient mice. The thyroid lesions in recipients of cells cultured with MTg and XMG-1.2 mAb also exhibited granulomatous changes, which differed qualitatively from the predominantly lymphocytic cell infiltrates in recipients of cells cultured with MTg alone. Recipients of MTg-activated spleen cells also developed severe granulomatous EAT when they were given injections of XMG-1.2 mAb. The effects of XMG-1.2 could be neutralized by IFN-gamma. Recipients of cells cultured in the presence of XMG-1.2 mAb had augmented autoantibody responses, although there were no apparent differences in the IgG subclass distribution of the anti-MTg autoantibody responses. These studies suggest that neutralization of endogenous IFN-gamma results in increased activity of cells capable of inducing granulomatous EAT in mice.

Animals↗

Case report 757: Giant cell tumor of rib.

A case of the rare occurrence of conventional GCT in a rib is presented. Due to its radiological aggressivity, the possibility of a MGCT was entertained clinically, and preoperative chemotherapy and radiation therapy were given. The literature on giant cell tumors of the ribs is reviewed, and their distinction from primary MGCT and other giant-cell-containing lesions is discussed.

Adult↗