Epstein barr virus IgG and EBER-1 in Burkitt's lymphoma children at a referral hospital in western Kenya.

Burkitt's lymphoma (BL) is a frequent childhood B cell non-Hodgkin's lymphoma (NHL) in equatorial Africa associated with infections. Chronic Epstein Barr virus (EBV) infections can lead to host immune stimulation that may trigger genetic translocation(s), neoplastic transformation and proliferation of B cells. We determined EBV immunoglobulin G (IgG) in sera from participants and EBER-1 in tumour sections in confirmed BL cases at Moi Teaching and Referral Hospital (MTRH). A cross sectional study of children with clinical and histology diagnosis of NHL from whom BL status were confirmed by immunohistochemistry (IHC) was carried out. Epstein Barr virus IgG in sera was determine using Enzyme-linked immunosorbant assay, IHC for EBER-1 and MYC protein in tumour sections. Demographic and clinical information were obtained from questionnaires and hospital files respectively. Ninety three percent of sera were EBV IgG positive of which 31.7% were confirmed as BL. All jaw BL tumours and 86.7% of BL tumours carried EBER-1 antigen. Odds ratio of EBER-1 positive was 1.39, 95% CI: 0.16-12.19 in BL tumours regardless of age or gender. EBV infection among the study participants may be associated with BL, however, EBER-1 and MYC negative in BL tumours suggest alternative BL pathogenesis or variant.

Primary intraosseous adenoid cystic carcinoma of the mandible: a comprehensive review and analysis of four new cases with emphasis on morphologic, immunophenotypic, and molecular characteristics.

OBJECTIVE: To comprehensively review the clinical manifestations, imaging, diagnosis, treatment, and pathologic features of primary intraosseous adenoid cystic carcinoma (PIACC) of the mandible and analyze PIACC histopathology and molecular features in four cases. STUDY DESIGN: We reviewed the literature and retrospectively studied four cases of PIACC. RESULTS: The clinical and imaging findings of PIACC are similar to other malignant or borderline-malignant mandible tumors. The four cases of PIACC included three males and one female (aged between 41 and 58 years). The histopathologic features of the tumors resembled those of ACC. We observed abundant osteoclasts resorbing bone at the leading edge of the tumors characterized by solid structure histology but not by the cribriform subtype. Additionally, all four cases showed abnormalities in the MYB gene and high expression of MYB protein. All patients survived for the duration of follow-up, and two patients had distant metastases (followed up for 3 to 36 months). CONCLUSIONS: PIACC is extremely rare and is often clinically misdiagnosed. Different histologic subtypes could show different mechanisms of invasion of the mandible. MYB gene and protein expression abnormalities can be used as indicators for the precise diagnosis of PIACC.

Epithelioid osteosarcoma of the mandible: a rare case with unusual immunoprofile.

A 42-year-old woman presented a large, nontender, quickly progressive mass in the left mandible. Radiograph showed extensive destruction of the angle, posterior body, and ramus of the left side of the mandible. The patient was surgically treated by hemimandibulectomy. Microscopically, the tumor was composed of large epithelioid cells, many of them showing polarized nuclei, and evident eosinophilic cytoplasm. The predominant pattern was trabecular, and rosette-like structures were also observed. Typical osteoid-containing cells surrounded by malignant cells were found in a few areas. Immunohistochemistry for a large panel of antibodies showed positivity for osteocalcin, osteonectin, osteopontin, VS38c, and S-100. CD34 saliented the hemangiopericytoma-like distribution of the blood vessels. Collagen I was focally positive for the extracellular matrix and malignant osteoid. All other markers were negative, including vimentin and cytokeratins. To the best of our knowledge, this is the first case of epithelioid osteosarcoma affecting the mandible and the second case affecting the jaws that has been reported in the literature.

Immunohistochemical features of proliferative marker and basement membrane components of two feline inductive odontogenic tumours.

Feline inductive odontogenic tumour (FIOT) is a rare and interesting odontogenic neoplasm in which the odontogenic epithelium has inductive potential to form aggregated foci of dental pulp-like mesenchymal cells. Two male cats aged 11 and 10 months presented with nasal swelling and a left maxillary mass. Histopathologically, the masses consisted of non-encapsulated invasive neoplasms exhibiting proliferation of epithelial and mesenchymal components with local infiltration into the maxillary bone in both cases. The epithelial component formed islands, anastomosing strands, and solid sheets of polygonal epithelial cells. Occasionally, these cells formed circular aggregates, resembling the cap stage of odontogenesis. Type IV collagen and laminin were constantly positive around the foci of epithelial cells, and Ki-67 positive indices were extremely low; therefore, these findings consistent with the benign clinical presentation of FIOT.

Plasma cells composing plasmacytoma have phenotypes different from those of myeloma cells.

We describe one relapsed case of plasmacytoma of mandibular bone. The organs of relapse were liver and bone marrow. At relapse, monoclonal gammopathy (IgG-kappa) was observed without suppression of IgA and IgM. By immunostaining, the plasma cells of both the original mandibular bone and liver were positive for the same cytoplasmic immunoglobulin light chain kappa. The proliferative plasma cells in the bone marrow had the phenotype of CD38+, CD19+, and CD56- by flow cytometry and showed the presence of the rearranged IgH gene by Southern blotting. In addition, the zone of the Ig class of the patient's serum was not so sharply defined by zone electrophoresis. These results suggest that the characteristics of plasma cells of plasmacytoma are different from those of multiple myeloma.

Mandibular osteosarcoma with unusual expression of alpha-actin smooth muscle antibody.

Mandibular osteosarcoma is a rare neoplasm, appearing in young adults as a mass often accompanied by pain, occasionally with paraesthesias, gingival haemorrhages and mobility of teeth, and rarely with ulceration of the skin or mucosa. Roentgenological lytic and/or sclerotic findings are non-specific. Some patients have a previous history of Paget's disease, antecedent radiation treatment, or fibrous dysplasia. Malignant osteoid production can be minimal, resulting in diagnostic difficulties. We report a case of a 33 year-old woman, who, in the absence of a clinical soil associated with the condition, was presented with advanced disease. Immunohistochemical study using alpha-actin smooth muscle antibody disclosed bizarre tumor cells with "dendritic" appearance, to our knowledge, never described thus far. This report draws attention to this uncommon neoplasm and reviews the pertinent literature related to this entity.

Human immunodeficiency virus-associated squamous cell carcinomas of the head and neck presenting as oral and primary intraosseous squamous cell carcinomas.

Six cases of squamous cell carcinoma arising in the head and neck of patients infected with the human immunodeficiency virus are described. This article reports the first two cases of primary intraosseous squamous cell carcinoma associated with infection with human immunodeficiency virus. Clinical presentation, results of imaging studies, histologic characteristics, therapies applied, and the clinical follow-up are described in detail for each of the six cases. These data are evaluated through a review of the current literature.

Intraoral presentation of anaplastic large-cell Ki-1 lymphoma in association with HIV infection.

Persons infected with human immunodeficiency virus have an increased risk for development of high-grade, non-Hodgkin's lymphomas. Anaplastic large-cell Ki-1 lymphoma is a recently described lymphoid neoplasm characterized by cellular pleomorphism, a sinusoidal growth pattern, and Ki-1 epitope reactivity. This type of lymphoma is often mistaken for metastatic carcinoma, melanoma, or malignant histiocytosis. Although persons with acquired immunodeficiency syndrome frequently have non-Hodgkin's lymphoma at extranodal sites, the oral cavity and mandible, in particular, are unusual locations. We report two cases of anaplastic large-cell Ki-1 lymphoma that occurred in persons with the human immunodeficiency virus and with initial presentation as soft tissue masses of the posterior mandible. Immunocytochemical studies were positive for Ki-1 (CD30) in both cases. In situ hybridization for Epstein-Barr virus-deoxyribonucleic acid was positive with tumor cells in both cases. Flow cytometry on paraffin, formalin-fixed tissue revealed tetraploidy and high proliferative fractions that are characteristic of high-grade lymphomas. Intraoral presentation of rapidly enlarging, soft tissue masses may represent a high-grade non-Hodgkin's lymphoma in persons with the human immunodeficiency virus. Although rare, anaplastic large-cell Ki-1 lymphoma should be considered and requires immunocytochemical study to eliminate the possibility of other malignant conditions associated with the acquired immunodeficiency syndrome.

Head, neck, and maxillofacial childhood Burkitt's lymphoma: a retrospective analysis of 31 patients.

Thirty-one children with Burkitt's lymphoma of the head, neck, and maxillofacial region diagnosed between 1976 and 1988 were reviewed. The age range was 2 to 17 years (median, 7.2 years), and 77.4% were males. The most common presenting symptoms were detectable masses, floating and/or painful teeth, enlarged cervical lymph nodes, sore throat, and neurologic signs. The predominant primary tumor sites were the jaws and tonsils. All patients were staged by a clinical staging system, 17 of them having stage I-II, and 14 stage III-IV. Levels of lactate dehydrogenase and ferritin were the only significant laboratory parameters correlating with initial staging and disease-free survival. Radiologic features in the jaws were poorly circumscribed destructive lytic lesions with migration and crypt destruction of unerupted teeth buds. Complete disappearance of these findings was noted after successful chemotherapy and clinical regression of the tumor. Eighteen (58.1%) patients attained complete remission with a follow-up of 5 to 100 months. Stage was the most significant variable affecting outcome, with 90.2% disease-free survival of stage I patients, 72.4% of stage II, and 18.2% of stage III-IV. Based on these results, it is concluded that localized (stage I and II) Burkitt's lymphoma is responsive to chemotherapy and thus has a favorable prognosis.

Multiple myeloma presenting as localized expansile jaw tumour.

Myelomatous involvement of the maxilla is an exceptionally rare occurrence, and the presentation of the lesion as an expansile jaw bone tumour has not been reported. 2 cases, one with a maxillary lesion, the other with a mandibular lesion are presented, both of which illustrate gross bone expansions. Additionally, 1 case presented with a rare biclonal IgG kappa and IgG lambda light chain secreting myeloma. Relevant clinical, immunological, histological, biochemical and histochemical features are presented and discussed, and suggestions pertaining to surgical management made.

An immunohistochemical and electron microscopic study of a central venous hemangioma of the mandible.

To date, 96 cases of central hemangiomas of the jawbones have been described in the literature. Of these cases, the mandible has been more affected than the maxilla, while approximately 50% of all cases occur in the first and second decades of life. Histopathologically, cavernous and capillary types are often found, in contrast to the central venous type, which is rare. We have recently treated a 44-year-old man, who was found to have a central venous hemangioma in his mandible. Immunohistochemical studies were performed using factor-VIII-related antigen as well as various lectins as markers for tumor endothelial cells. Our results showed that four kinds of lectins (UEA-I, PNA, ConA, and DBA) were useful for the marker as factor-VIII-related antigen. Scanning electron microscopic findings of this tumor demonstrated that the lumina of the blood vessels were more rough, while the lining endothelial cells were more irregular when compared with those of the normal vascular system.

[Mesenchymal chondrosarcoma. Anatomico-clinical, immunohistochemical and ultrastructural study. Apropos of a case]. / Chondrosarcome mésenchymateux. Etude anatomo-clinique, immunohistochimique et ultrastructurale. A propos d'une observation.

One case of mesenchymal chondrosarcoma of the mandible is reported in a 18 years-old man. The patient noted swelling and pain and roentgenography showed an osteolytic lesion of the right mandible. Histologically, the feature was obvious with chondroid sheets of round ovoid or elongated cells. Immunohistochemically, numerous cells had positive S-100 protein and vimentin. The electron microscopy showed numerous undifferentiated cells and also fibroblastic and cartilaginous cells. The prognosis of this tumor, usually bad, cannot be yet appreciated in this case (follow-up of only 3 months). The histogenesis of this peculiar variety of chondrosarcoma is discussed.

Basement membrane confinement of epithelial tumor islands in benign and malignant ameloblastomas.

The extent of basement membrane confinement among 5 cases of ameloblastoma and a malignant counterpart were studied by immunohistochemistry. For these studies, antibodies to 2 basement membrane components, Type IV collagen and laminin, were studied by immunohistochemistry. Our results show that the tumor islands of ameloblastomas are circumferentially delineated by a linear staining to both antibasement membrane antibodies, and that these findings were consistent for all of the patterns of ameloblastoma investigated. These data suggest that ameloblastomas spread into tissue spaces by expanding their compartmental volumes rather than by secreting proteinases that disrupt their basement membranes compartmental barriers. In contrast, the single case of malignant ameloblastoma investigated was not delineated by circumferential linear basement membrane components. However, this tumor and all of its metastases did contain numerous focal areas of Type IV collagen and laminin immunoreactive materials. Collectively, these studies indicate that the use of specific antibodies to basement membrane components may help to differentiate ameloblastomas from malignant lesions.

B-cell lymphoma in two monogamous homosexual men.

Opportunistic infections and malignant neoplasms have been described in homosexual men in association with immunologic abnormalities. We observed the development of malignant B-cell lymphomas in two homosexual men who had had a monogamous relationship for two years. Patient 1 had an aggressive, monoclonal, small, noncleaved, non-Burkitt's lymphoma ("undifferentiated lymphoma"), associated with severe immunocompromise. Patient 2 manifested a monoclonal, small, cleaved, follicular center cell lymphoma, with a follicular pattern, two months later. No common acute infection was detected. Staining for Epstein-Barr nuclear antigen in malignant tissue was negative in the second patient. However, the possibility of a transmissible agent as a causative factor cannot be excluded, and further study of similar patients is warranted.