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N Naka

Publications and source records attributed to N Naka.

14 recordsLinked to original sources
PubMed1996

Expression of Epstein-Barr virus latent infection genes and oncogenes in lymphoma cell lines derived from pyothorax-associated lymphoma.

Malignant lymphomas frequently develop in the pleural cavity of patients with long-standing pyothorax. The term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. Most PALs are diffuse lymphomas of the B-cell type and contain Epstein-Barr virus (EBV) DNA. We have established 2 lymphoma cell lines from biopsy specimens of PAL cases, OPL-1 and OPL-2, and examined their growth characteristics and the expression of EBV latent infection genes and oncogenes. OPL-2 exhibited a more rapid growth and higher saturation density than OPL-1, and only OPL-2 exhibited colony-forming activity in soft agar. OPL-1 and -2 were positive for B-cell differentiation markers and showed clonal surface immunoglobulins. Both line contained a single predominant form of episomal EBV DNA, indicating clonal cellular proliferation of an EBV-infected progenitor cell. OPL-1 and -2 contained type B and A EBV genome, respectively. Expression of EBV nuclear antigen (EBNA)2 mRNA and protein was detected by Northern and Western blot analysis in OPL-1, but not in OPL-2. On the other hand, the expression of latent membrane protein (LMP)1 mRNA in both OPL-1 and -2 was extremely weak and detectable only by reverse transcription-polymerase chain reaction. Protein expression of LMP1 was not observed by Western blot analysis or immunocytochemistry. Both lines expressed c-myc mRNA. Only OPL-1 expressed mRNA of c-fgr, an oncogene whose expression is upregulated by EBNA2. Both OPLs expressed bcl-2 mRNA without detectable expression of LMP1 protein.

Aged↗
PubMed1996

Prognostic factors in angiosarcoma: a multivariate analysis of 55 cases.

Data for prognostic factors in angiosarcoma (AS) are limited, prompting a large-scale study of AS with multivariate analysis. To analyze prognostic factors in angiosarcoma (AS), clinical and histologic findings in 55 patients collected from hospitals in Japan were reviewed. Prognostic factors were evaluated by univariate and multivariate Cox's proportional hazards models. The study involved 32 males and 23 females, ages 18-93 (median, 69) years. The primary sites of tumors included head and neck (32 cases), trunk (10), extremities (3), spleen (3), breast (3), and other (4). The overall 2-year survival rate was 21%. Univariate analysis of clinical factors including age, sex, size and depth of tumor, tumor-related symptoms, interval between onset of symptoms and admission, surgical procedures, adjuvant chemotherapy, and adjuvant radiotherapy showed that age, tumor size, and mode of treatment were significant for survival. Histologic factors analyzed were mitotic counts, cellularity, cellular pleomorphism, extent of necrosis, vascular differentiation, and nonspecific diagnosis. Only mitotic counts were significant for prognosis. Multivariate analysis on these four factors revealed that tumor size, mode of treatment, and mitotic counts were independent prognostic factors.

Adolescent↗
PubMed1995

Use of immunohistochemical procedures in diagnosing angiosarcoma. Evaluation of 98 cases.

BACKGROUND: Differential diagnosis of angiosarcoma, predominantly showing a non- or poorly vasoformative proliferation from other types of sarcomas, poorly differentiated carcinomas, and amelanotic melanoma, is often problematic. METHODS: The use of antibodies directed against Factor VIII-related antigen (FVIIIRA), Ulex europaeus lectin type 1 (UEA-1), CD31, and vascular endothelial growth factor (VEGF) in the diagnosis of angiosarcoma was examined in 98 cases of autopsy-proven angiosarcoma diagnosed during 1974-1990 in a survey of 178 Japanese hospitals. Reactivity of angiosarcoma cells for epithelial membrane antigen, cytokeratin, and melanoma cell antigen (HMB45) also was examined. RESULTS: Histologic specimens were formed exclusively by vasoformative areas in 32 cases and combined vasoformative and varying extents of non- or poorly vasoformative areas in another 66 cases. In vasoformative areas, the proliferating cells showed a diffuse positive reaction in the cytoplasm and/or cell surface for anti-FVII-IRA in 82 (84%) of 98 cases, for anti-CD31 in 78 (80%), and for UEA-1 in 69 (70%). In non- or poorly vasoformative areas, the positivity rate for FVIIIRA, CD31, and UEA-1 was 29%, 62%, and 46%, respectively. A positive reaction was found for either one of three endothelial markers in the non- or poorly vasoformative areas of 57 cases (86%). Epithelial membrane antigen and anticytokeratin antibody were positive in 4 and 11 cases, respectively, in the vasoformative areas and in 3 and 14 cases, respectively, in non- or poorly vasoformative areas with a simultaneous positive reaction for either one of three endothelial cell markers. None of the proliferating cells showed a positive reactivity for HMB45. The positivity rates of the angiosarcoma cells for each marker were different according to the primary tumor sites. The angiosarcoma cells in non- or poorly vasoformative areas showed the lowest positivity rate for anti-FVIIIRA in the heart (9%) and for anti-CD31 in the extremities (17%) and the highest positivity rate for anticytokeratin in the trunk (60%). Ulex europaeus lectin type 1 had almost the same reactivity rate (30-56%) in every organ. Angiosarcoma cells in 13 (36%) of 36 biopsy specimens and 8 (14%) of 56 autopsy specimens were positive for the anti-VEGF antibody. CONCLUSION: These findings suggest that the combined use of endothelial cell markers including FVIIIRA, UEA-1, and CD31 is useful in the diagnosis of angiosarcoma, especially in cases exclusively with a non- or poorly vasoformative pattern.

Adolescent↗
PubMed1995

Angiosarcoma in Japan. A review of 99 cases.

BACKGROUND: Angiosarcoma is rare, and information about its clinical features are limited. Therefore, a large scale study of angiosarcoma was performed in Japan. METHODS: Through a nationwide Japanese study, 99 cases of angiosarcoma were collected and their clinicopathologic findings were summarized relative to predisposing risk factors. RESULTS: The patient age at diagnosis was 3-92 years, (mean, 62 years), with a two to one male to female ratio. The head and face were the most common primary site (29 cases); other sites were liver (17); trunk (13): pleural cavity (6), chest wall (2), abdominal wall (2), buttock (2), inguinal region (1); heart (12); and extremities (7). The proven predisposing risk factors included chronic pyothorax for angiosarcoma in the pleural cavity (six), thorotrast in the liver (five), radiotherapy to the abdominal wall and buttock (four), and chronic limb edema of the forearm (one). Irrespective of primary sites, the majority of cases had metastases to lung in 72 cases, bone in 42, liver in 36, regional lymph nodes in 30, and adrenal gland in 24. The 2-year survival rate was 17%. CONCLUSIONS: This study describes a different etiology in the development of angiosarcoma in patients from Japan compared with that of patients from Western countries, though the frequency of angiosarcoma among all soft-tissue sarcomas was similar in both areas. In Japan, chronic pyothorax, radiotherapy, and thorotrast proved to be distinctive causative factors of angiosarcoma.

Adolescent↗
PubMed1995

Angiomatous lesions in the wall of chronic pyothorax.

Formation of massive hematoma in the cavity of chronic pyothorax (CP) has been described previously, but its mechanism remained unclear. In the present study of 99 cases, the vascular lesions in the wall of CP were examined by histological methods, including immunohistochemistry. The age of patients ranged from 42 to 80 years (mean 57 years), with a male to female ratio of 3.3. Histologically the CP wall was covered by a fibrin layer containing cellular debris and red blood cells. Directly beneath the fibrin layer, a fibrous layer of varied thickness was present that extended to the subserosal tissue or so-called fat plane defined by computed tomography. At the junctional region between the fibrin and fibrous layer, angiomatous lesions were observed in 33 cases (Group I). In the fibrin layer of this group, dilated vessels frequently bulged into the pleural cavity. In another two cases, closely packed large vessels with irregularly thickened walls resembled an arteriovenous fistula (Group II). In seven patients, histologic specimens showed a total necrosis. The remaining 57 cases without the findings in Groups I and II were categorized as Group III. These findings suggested that formation of angiomatous lesion preceed intrapleural bleeding, which occasionally progressed to form a massive hematoma.

Adult↗
PubMed1995

Expression of vascular endothelial growth factor and its receptor mRNA in angiosarcoma.

BACKGROUND: Vascular endothelial growth factor (VEGF), a specific mitogen for endothelial cells in vitro, can be angiogenic factor in vivo. VEGF is known to be produced by several tumor cells and plays an important role for neovascularization in tumor tissue. Recently, tyrosine kinase encoded by the flt gene was identified as a receptor for VEGF. Angiosarcoma (AS) is a rare malignant tumor that arises from endothelium. At present, little is known about a mechanism of proliferation of the AS. EXPERIMENTAL DESIGN: In an immunohistochemical study of 99 cases of AS, 11 cases showing a positive reaction for anti-VEGF Ab were selected for the present study. In these cases, expression of VEGF and its receptor (flt) mRNA was examined by in situ hybridization: sense and antisense probes for VEGF and flt mRNA were used. RESULTS: In situ hybridization study with antisense probes revealed that the VEGF mRNA was expressed in AS cells and mononuclear cells in all but one case. Intensity of VEGF staining by immunohistochemistry correlated well with VEGF mRNA expression. The flt mRNA was expressed in AS cells in all 10 cases that were positive for VEGF mRNA. Sense probe for VEGF and flt mRNA gave no positive reactions. CONCLUSIONS: These findings suggest a presence of paracrine or autocrine mechanism of proliferation in AS through VEGF and its receptor flt.

Aged↗
PubMed1994

A staging system for soft-tissue sarcoma and its evaluation in relation to treatment.

In order to define the significant factors for a staging system of soft-tissue sarcomas (STS), histologic and clinical findings in 190 adult patients with localized STS in the extremities and trunk were reviewed. The male-to-female ratio was 1.21. The histologic grading of tumors was defined according to the criteria recently proposed by us: tumors were low-grade in 65 cases, intermediate-grade in 57 cases and high-grade in 68 cases. The initial surgical procedure was as follows: intracapsular excision in 9 cases, marginal excision in 104 and wide local excision in 77, including 15 amputations. The mode of treatment was surgery alone (101 patients), surgery and chemotherapy (58), surgery and radiotherapy (22) and surgery and combined chemo- and radiotherapy (9). Univariate analysis revealed histologic grade, sex, tumor size and tumor depth to be significant prognostic factors. Multivariate analysis revealed histologic grade to be the only independent factor for prognosis. Significant clinical factors in each histologic grade were then evaluated. In the low-grade group, local recurrence significantly affected prognosis. Most of the patients with local recurrence had had marginal resection as the initial surgical procedure. No clinical factors affecting prognosis in the intermediate-grade group could be determined. In the high-grade group, patients with wide local excision and adjuvant chemotherapy had a better prognosis than those with marginal excision with or without adjuvant chemotherapy and wide local excision without chemotherapy (p = 0.09). In conclusion, histologic grade was the only significant factor for the staging of STS. On the basis of our staging system, different modalities of treatment for each grade of STS might be indicated; adequate surgery is essential for the prevention of local recurrence, which resulted in reduced mortality in patients with low-grade STS. For high-grade STS, the prevention of distant metastasis by combined extensive surgery and adjuvant chemotherapy may make long-term survival possible.

Adult↗
PubMed1994

Angiosarcoma developing from chronic pyothorax.

In our previous study, we suggested that long-standing pleural inflammation might be an etiological factor for development of pleural soft-tissue sarcomas, especially malignant fibrous histiocytoma and angiosarcoma (AS). To study the etiological importance of chronic pyothorax for development of pleural AS, a nationwide study of AS in Japan was carried out. Histological and clinical findings in 99 collected cases with AS were reviewed. Six (6%) of the 99 cases were chronic pyothorax-associated AS. Another three cases of pyothorax-associated AS previously reported by us were also included. They were eight males and one female from 45 to 74 yr of age (median 65 yr). All patients had a 15- to 40- (mean 30) yr history of chronic tuberculous pyothorax. Histologically, the tumors contained irregular, occasionally dilated vascular channels, which were invested by tumor cells with an epithelioid appearance. From the statistical data reported previously, annual incidence of AS is probably 0.01 to 0.02 per 100,000 population. Meanwhile, there was an incidence rate of pyothorax-associated AS among chronic pyothorax patients of 0.036 per 100 patients. Thus, the frequency rate of pyothorax-associated AS is supposedly over 3600-fold higher than that in normal population. The present study shows that chronic tuberculous pyothorax is one of the causes of AS development.

Aged↗
PubMed1994

Occurrence of monocytoid B-lymphocytes in Hodgkin's disease.

The nature and frequency of occurrence of monocytoid B-lymphocytes (MBL) was examined in 118 cases of Hodgkin's disease. Monocytoid cells were present in six cases (5%), four nodular sclerosis and two mixed cellularity. These cells were CD20+, CD3-, CD45RO-, KP-1-, PGM1-, with occasional positive reaction for MB-1 and CD74, indicating their B-cell nature, i.e., MBL. The MBL were distributed in the periphery of the nodules of nodular sclerosis accompanying centrally located Reed-Sternberg cells, although Reed-Sternberg cells were observed in some MBL clusters. In the mixed cellularity, MBL were located in the para-follicular area occasionally adjoining the lymph follicles. Because previous studies suggested depressed immune function in autoimmune diseases, acquired immune deficiency syndrome, and older persons to be responsible for the occurrence of MBL, it is possible that in some patients development of foci of MBL under immunodeficient conditions progresses to Hodgkin's disease.

Adult↗
PubMed1993

Usefulness of argyrophilic nucleolar organizer staining for histologic grading of soft-tissue sarcomas.

Accurate histologic grading is essential for making a proper therapy decision in soft-tissue sarcomas (STS). The usefulness of the argyrophilic stain for nucleolar organizer region (AgNOR) in assessing the histologic grade of STS has been examined. One hundred and forty-two patients with STS confined to the extremity and trunk were selected. Tumors were classified based on the criteria of Enzinger and Weiss ["Soft-Tissue Tumors." St. Louis: C. V. Mosby, 1983]. In addition, non-specific classification was made based on the shape of proliferating cells occupying more than 50% of the field in the sections such as pleomorphic cell, small round cell, spindle cell, epithelioid cell, myxoid, and unclassified tumors. The mean number of AgNOR dots per nucleus of tumor cells was calculated in 200 cells (AgNOR count). Each category of non-specific classification was divided into a high-count group (< 8 AgNOR count) and a low-count group (> 8 NOR). The low-count group showed a significantly better prognosis than the high-count group in small round cell and spindle cell tumors (P < 0.007 and P < 0.0005, respectively). Similar results were obtained in pleomorphic cell tumors, though they were statistically not significant because of the relatively small number of examined cases. Most patients with epithelioid cell and myxoid tumors were in the low-count group. These findings suggest that the assessment of histologic grading of STS could be made effectively by the non-specific classification and the aid of AgNOR staining.

Actuarial Analysis↗
PubMed1993

Pubic-type dislocation of the hip combined with fracture of the ipsilateral greater trochanter. A case report.

Traumatic anterior dislocation of the hip is a relatively uncommon injury, and when it does occur it is frequently combined with osteochondral fracture of the femoral head or the acetabulum. Anterior dislocation of the hip with an associated fracture of the ipsilateral greater trochanter is extremely rare. This paper presents a case of this rare type of injury and clarifies the mechanism of the injury using a cadaver specimen.

Adult↗
PubMedDate not supplied

Usefulness of argyrophilic nucleolar organizer staining for predicting prognosis of patients with recurrent soft tissue sarcoma.

Local recurrence of tumor is a common phenomenon in soft tissue sarcoma (STS) and may be accompanied by an increase in malignant potential. In the present study, an increase of proliferative activity in recurrent tumors compared to primary tumors was observed using a silver stain for nucleolar organizer regions (AgNOR), and its implication for predicting prognosis is assessed. 44 patients with STS showing local tumor recurrence were selected. Local recurrence was defined as new tumor growth more than 2 months after the initial surgery in the same region where the primary tumor occurred. All patients received surgery, followed in 11 patients by adjuvant radiotherapy and/or chemotherapy. The histologic subtype was malignant fibrous histiocytoma in 22 cases, synovial sarcoma in 5, leiomyosarcoma in 4, liposarcoma in 3, malignant schwannoma in 3, and others in 7. The interval between initial surgery and local recurrence ranged from 2 to 72 months. No patients changed from one histological subtype to another. Histological changes included an increase in mitosis, cellularity, and sclerosis in 43.2, 31.8, and 27.3%, respectively. The AgNOR count (mean +/- SD) in recurrent tumors (7.22 +/- 2.59) was significantly higher than that in primary tumors (5.58 +/- 2.28; p < 0.0057), clearly showing a tendency for an increase in proliferative activity during recurrence. The 5-year survival rate of patients with a marked increase (> 4) in AgNOR count (16.7%) was worse than with minor to moderate increases (60.0%; p < 0.02). Marked AgNOR increase was more frequently observed in the tumors located in the head and neck and retroperitoneum (40%) than in other sites (9%). Irrespective of the primary site of tumors, a marked AgNOR increase resulted in an unfavorable prognosis. Multivariate analysis of change in histologic factors including AgNOR, cellularity, mitotic counts, pleomorphism, myxoid change, necrosis, sclerosis, and tumor size showed that increase of AgNOR counts was significant (p < 0.05). The present findings suggest that AgNOR counts can be used as a prognostic factor in recurrent STS.

Adult↗