Malpractice and criminal responsibility in Japan.
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Biomedical subjects
Publications and source records attributed to Masahito Hatori.
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We present a rare case of subcutaneous lesions arising in the palm of a 4-year-old girl. Histologic examination of the biopsy specimens showed granulomatous inflammation with focal necrobiosis, which was consistent with subcutaneous granuloma annulare. Subcutaneous granuloma annulare is a self-limited disease and treatment is not required, although recurrence and/or multiple lesions are frequent.
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Giant cell tumor of the bone (GCT) is a relatively uncommon tumor. It is characterized by the presence of multinucleated giant cells. GCT is a primary benign tumor but may evolve into a malignant tumor, usually after irradiation. We report a rare case of osteosarcoma arising ten years after the primary surgery for GCT without radiation. A 45-year-old woman presented with severe right knee pain after suffering contusion. Roentgenogram revealed a bone tumor in the lateral femoral condyle of the right knee. Histopathological examination demonstrated the features of GCT, and treatment consisted of curettage and bone grafting. Four months after the operation, multiple lung metastases of GCT occurred, which were treated by partial lobectomy. Ten years after the primary treatment, severe knee pain recurred. Roentgenogram and magnetic resonance imaging (MRI) demonstrated a destructive lesion in the lateral condyle of the right knee. Histopathological examination demonstrated a lacy pattern of osteoids and abnormal mitoses in the aggregated atypical mononuclear cells, indicating osteosarcoma. Despite above-knee amputation and chemotherapy, scapular and lung metastases developed and the patient died five months after above knee amputation. One may question whether the primary GCT contained some malignant cells. However, given the aggressiveness of the malignant tumor, this is unlikely. The recurrence of pain and aggravation of bone destruction many years after the primary treatment suggest malignant transformation of GCT.
We experienced two unusual cases of diffuse large B-cell lymphoma (DLBCL), which occurred in a patient with neurofibromatosis type I and a patient with neurofibromatosis type II. B-cell lymphoma is one of the most common phenotypic subgroups of malignant lymphoma. Neurofibromatosis I is characterized by café-au-lait spots and neurofibromas. Neurofibromatosis II typically consists of bilateral schwannomas of the acoustic nerve. Malignant lymphomas rarely coexist with neurofibromatosis I, and no coexistence with neurofibromatosis II has been reported. The patient with neurofibromatosis I was a 50-year-old Japanese woman, clinically manifesting von Recklinghausen's disease since infancy, who noticed an egg-sized tumor in her shoulder. The patient with neurofibromatosis II was a 39-year-old Japanese man who noticed multiple soft tissue tumors in his neck, buttock, and elbow. Biopsied materials from both cases were examined by multiparameter methods, including flow cytometry. Flow cytometry revealed large-scale cells to be tumor cells, and they were positive for CD19, CD20, and CD22. Both patients received chemotherapy, and the tumors disappeared. The patient with neurofibromatosis I was alive without recurrence at 4 years after treatment, while the patient with neurofibromatosis II died of recurrence. To the best of our knowledge, this is the first case of malignant lymphoma arising in a neurofibromatosis II patient. As for neurofibromatosis I, there were some reports about occurrence of malignant lymphoma. It is important to be aware of possibility of association of malignant tumors not only of the nervous system but also of unrelated to the nervous system when tumors appear in neurofibromatosis patients.
Enchondromas are the most common benign cartilaginous bone tumors arising in the medullary cavity of the small bones of the hand. In contrast, chondrosarcomas, commonly occurring in the pelvis and proximal femur and humerus, are very uncommon at this site. We report an unusual case of chondrosarcoma arising in the ring finger proximal phalanx with its radiological and histological features and reviewed the literature. The patient was an 80-year-old man whose chief complaint was swelling and pain for seven years. The findings of cortical irregular thickening by plain radiography and computed tomography and soft tissue extension by magnetic resonance imaging suggested the tumor was chondrosarcoma rather than a common enchondroma. Thorough curettage and artificial bone grafting was performed because of the age of the patient, his senile dementia and the strong desire of the patient and his family. Histological examination revealed that the tumor was composed of polygonal cells with eosinophilic cytoplasm proliferating in the chondromatous matrix with partially myxoid changes. Nuclear irregularity, binucleated cells, bone permeation and encasement were observed and the tumor was diagnosed as grade 2 chondrosarcoma. The tumor recurred five months after surgery. Amputation of the ring finger including the distal part of the 4th metacarpal was performed. At two years after surgery, the patient was free from recurrence or lung metastasis. In conclusion, details of radiological as well as pathological findings are essential for differential diagnosis between benign enchondroma and chondrosarcoma in the hand. Chondrosarcoma of the hand requires a prompt and more radical treatment than enchondroma. Wide excision is recommended to avoid local recurrence or metastasis.
Neurofibromatosis type 1 (NF1) or von Recklinghausen's disease is a genetic disease generally characterized by café-au-lait spots and neurofibromas. Malignant tumors of the nervous system, such as malignant schwannomas, gliomas, or astrocytomas, have been well known to coexist with neurofibromatosis. However, occurrence of malignant tumors unrelated to the nervous system is rare. We report an unusual case of a 29-year-old NF1 female suffering from malignant peripheral nerve sheath tumor (MPNST) that eventually developed osteosarcoma in the proximal femur. Osteosarcoma is the most common high-grade malignant bone tumor in which the neoplastic cells produce osteoid. At 23 and 24 years old, she underwent excision of MPNST in the left posterior thigh. No osteosarcomatous portion was identified in these specimens. The patient underwent postoperative chemotherapy. At 29, left proximal thigh pain and swelling appeared. Computed tomography demonstrated cortical bone destruction in the left proximal femur where MPNST occurred. Magnetic resonance imaging revealed extraskeletal growth of the tumor. Bone scintigraphy demonstrated increased uptake in the left proximal femur. Hip disarticulation was performed. The removed tumor was composed of highly anaplastic cells. Lace-like irregular osteoid formation was observed among the tumor cells. MPNST component was totally absent. The tumor was diagnosed as osteoblastic type osteosarcoma. Two months after disarticulation the patient died of bilateral pulmonary metastasis. The correlation between the histogenesis of osteosarcoma and the genetic abnormality in NF1 patients has not been elucidated, but the finding of osteosarcomatous transformation in this case suggests the divergent cellular differentiation to mesenchymal malignant tumors of neuroectodermal tissue in NF1 patients.
Ewing's sarcoma (ES) is a highly malignant tumor composed of uniform small round cells. Recently, a single biologic entity, Ewing's sarcoma family of tumors (ESFT) has been accepted. The entity includes ES, extraskeletal Ewing's sarcoma (EES) and primitive neuroectodermal tumor (PNET). ESFT cells have immunoreactivity for CD99, an antigen determined by the MIC2 gene. Most ESFT has the (11;22) (q24;q12) translocation. The translocation results in the fusion of the EWS gene with the transcription factor gene FLI1 which has been considered a hallmark of ESFT. We present an extremely unusual case with ESFT in a spinal nerve root mimicking a neurogenic dumbbell tumor. A male aged 20 years noticed pain in his right buttock. Magnetic resonance imaging (MRI) revealed a mass in the right L5/S intervertebral foramen and the lesions in the sacrum. Surgery was performed with a presumptive diagnosis of a nerve sheath tumor. At surgery, the tumor was located in the right L5 nerve root sleeve. The sacral lesions were observed closely. At one month after surgery, radiologically multiple lesions were detected in the pelvic bones. Microscopically the lesions from the root and ilium were composed of small round cells immunoreactive for CD99. Reverse transcription-polymerase chain reaction detected transcripts resulting from the fusion of the EWS gene with FLI1 genes in the iliac lesion. Immunoreactivity for CD99 and detection of the EWS-FLI1 hybrid transcripts are important for the correct diagnosis of ESFT arising in an unusual location.
Adamantinoma is known as a low-grade malignant biphasic tumor. Classic adamantinoma is in general characterized by admixture of both epithelial and osteofibrous components that are associated with various proportions and differentiation patterns. Osteofibrous dysplasia (OFD) is a self-limited benign fibro-osseous lesion of bone during infancy and childhood. OFD-like adamantinoma is characterized by predominance of osteofibrous tissues, in which small groups of epithelial cells are only detected by careful search or immunohistochemistry. There have been controversies as to the potential correlation among OFD, OFD-like adamantinoma and classic adamantinoma. We report an unusual case of adamantinoma arising in the tibia, with an extensive review of the literature. The present findings suggest a direct correlation between OFD-like adamantinoma and classic adamantinoma. At the age of 12 years, the tibial biopsy lesion was diagnosed as OFD. At the age of 23, the lesion became larger and more destructive on x-ray films. The biopsy lesion was diagnosed as classic adamantinoma. Wide excision was performed. The primary lesion was retrospectively diagnosed as OFD-like adamantinoma because of presence of keratin-positive epithelial cells within the stroma. At five years after surgery, the patient was free from recurrence or metastasis. The retrospective histological findings of OFD-like adamantinoma in the original biopsy and of a classic adamantinoma in all sections of the later resection specimen raised the possibility of an unusual progression of OFD-like adamantinoma to a classic adamantinoma. The present case and the literature review suggest that an OFD-like adamantinoma may be a precursor lesion of classic adamantinoma. Therefore, the possibility of progression of OFD-like adamantinoma to a classic adamantinoma should be kept in mind, particularly when the destructive changes are seen radiologically.
Desmoid tumors are benign fibrous neoplasms which arise from the fibrous tissue of intra- and extra- abdominal sites, but their clinical management is sometimes difficult because of extensive infiltration into the surrounding tissues. Desmoid tumors commonly occur in women, especially after childbirth. Recently, both clinical and experimental findings indicate the possible roles of sex steroids in the development and progression of desmoid tumors but detailed information is still ambiguous. In this study, we first examined immunoreactivity of sex steroid receptors in desmoid tumors (27 cases) by immunohistochemistry and compared the findings with those in reactive self-limiting lesions associated with fibrosis (8 cases). Estrogen receptor (ER) alpha and ERbeta immunoreactivities were detected in 7.4% (2/27) and 7.4% (2/27) of desmoid tumors, respectively. One desmoid tumor expressed both ERalpha and ERbeta. Progesterone receptor (PR)-A and PR-B were detected in 25.9% (7/27) and 33.3% (9/27), respectively, and androgen receptor (AR) in 52.9% (14/27). In reactive lesions with fibrosis, only AR was detected in 37.5% (3/8). Sex steroid receptor mRNAs was further examined by reverse transcription and polymerase chain reaction (RT-PCR) analysis using fresh frozen tissues, demonstrating the expression of PR (PR-A and/or PR-B) and AR mRNAs in eight desmoid tumors examined and all cases of reactive fibrosis. These results indicate that sex steroid hormones might play an important role in the pathogenesis of desmoid tumors and could lead to the introduction of novel hormone therapeutic approaches in managing patients with recurrent desmoid tumors.
Ewing's sarcoma, a small round cell sarcoma arising in soft tissue as well as the bone, is one of the most malignant tumors in children and young adults. Few established cell lines of extraskeletal Ewing's sarcoma (EES) have been reported, which made it difficult to examine the biological features of EES. Therefore, we have established a new clonal cell line of EES. We report its morphological characters, results of chromosomal and immunohistochemical analysis. A piece of tumor obtained from the 18-year-old female patient with EES was xenografted in a nude mouse. In vitro subcultured cells were then obtained from this xenograft. A clonal cell line was subsequently established by limiting dilution and designated EES1. EES1 cells had a doubling time of 24 hours. In the xenografted tumor, the cells expressed vimentin, CD99 (MIC2), neuron specific enolase (NSE) and cytokeratin. The original tumor cells also expressed vimentin, CD 99, and NSE, but was negative for cytokeratin. The morphological and immunohistochemical features of this cell line established, except for cytokeratin expression, were consistent with those of the primary tumor. Cytogenetic analysis of EES1 revealed chromosomal translocation of t(11; 12)(q24;ql2). The chimeric fusion of the Ewing's sarcoma gene in band 22q12 with the Friend leukemia virus integration-1 gene in band 11q24 was also demonstrated. Fluorescence in situ hybridization further confirmed the presence of translocation involving the Ewing's sarcoma gene in both the primary tumor and EES1 cells. In conclusion, we have established a human EES cell line EES1, which will provide a useful model for studying various aspects of human EES.
Crow-Fukase syndrome (CFS) is a rare multi-system disorder, characterized by polyneuropathy, organomegaly, endocrinopathy, M-proteins, skin changes and anasarca, with or without myeloma. The pathophysiology, diagnosis, and treatment of CFS are controversial. CFS may be associated with the overproduction of vascular endothelial growth factor (VEGF). However, there have been no reports of monitoring the serum VEGF level after recurrence, to the best of our knowledge. We report a 54-year-old man with CFS presenting with a 3-year history of ascites, anasarca, weakness of the lower extremities, and plasmacytoma in the scapula. At the initial examination, the VEGF level was 1,590 pg/ml (the VEGF level of a healthy control, 78.4 +/- 75.2 pg/ml). After initial treatment with chemotherapy and irradiation of the affected shoulder, the VEGF level decreased to 154 pg/ml and the symptoms disappeared. Twenty one months later, gate disturbance and anasarca recurred, and the VEGF level was over 2,000 pg/dl. After total scaplectomy, the VEGF level decreased to 730 pg/dl and the symptoms disappeared. The serum level of VEGF well correlated to the clinical course of the patient. In conclusion, measurement of the VEGF level is useful for diagnosing CFS and for monitoring its clinical course.
Implantation of bone morphogenetic protein (BMP) using a carrier or by BMP gene transfer into rodent muscle can induce bone formation. Implanted BMP becomes bioactive immediately after implantation. In BMP gene transfer, there is a time-lag between the secretion of gene products and bone formation. We analyzed the gene expression of chondrogenic and osteogenic specific markers in the process of ectopic bone formation by using semi-quantitative RT-PCR. A plasmid vector containing mouse BMP4 gene (pCAGGS-BMP4) was transferred into the gastrocnemius muscles of mice using electroporation. Histological examination revealed the process of endochondral bone formation in the pCAGGS-BMP4 transferred muscles. As chondrogenic markers, aggrecan gene maximal expression was detected on day 7 and decreased by day 14, and for collagen X the gene maximal expression was on day 10. As osteogenic markers, osteocalcin (OCN), bone sialoprotein (BSP) and osteopontin (OPN) gene expressions were clearly detected from day 10 and then increased by day 14. In conclusion, the present study proved that ectopic bone formation by BMP4 gene transfer into the muscle induced endochondral ossification that corresponded well with that to that by implantation of demineralized bone matrix.
SAPHO syndrome is a group of bone and joint abnormalities associated with skin lesions. A 29-year-old male presented with severe acne on his trunk and anterior chest wall, right knee and foot pain. Radiographs and magnetic resonance images showed hyperostosis in the sternocostoclavicular region, sclerosis of one-third of the right distal 5th metatarsal bone and bony outgrowth from the medial condyle of the right femur. The histological findings of the biopsy specimen were consistent with-those of old osteomyelitis. All fungal and microbacterial cultures were negative. Pain and swelling of the right knee and foot repeated remission and aggravation. There were no radiological changes of the above-mentioned lesions noted within 4-years follow-up.
Ollier's disease is a rare disorder characterized by multiple enchondromas with a unilateral predominance, especially in fingers in early childhood. We experienced a case of Ollier's disease treated four times with simple curettage from the age of 2 years and alpha-tricalcium phosphate cement grafting at the age of 21 years. The forth curettage was performed when the patient was 15 years old and preoperative X-rays had shown remarkable finger deformities. Postoperative casting of the involved joints was necessary to prevent fractures but led to some finger contractures. Following X-rays demonstrated incredible improvement of the appearance. This suggests that simple curettage alone at an early stage of Ollier's disease provide cosmetic improvement. At the age of 21 years our patient showed enlargement of the intramedullary finger lesions again. Some lesions seemed to be impending pathological fractures. This time we chose alpha-tricalcium phosphate cement to fill the cavities after curettage had been carried out. Harvesting a large amount of autologous bone was not required. All activities of daily life could be resumed immediately after surgery and none of the finger joints showed further restriction of motion. X-rays taken three years after the operation showed new bone ingrowth surrounding the material with little evidence of absorption. To our knowledge, this may be the first case of Ollier's disease treated with artificial bone grafting reported in the English literature.
A 45-year-old woman presented with one-year history of a mass on her chest. Computed tomography and magnetic resonance imaging demonstrated a tumour near the sternoclavicular joint. The tumour was diagnosed as osteolipoma histologically after resection. Osteolipoma is a rare tumour and this may be the first report of osteolipoma arising adjacent to the sternoclavicular joint.
Dislocation of the tibiotalar joint without associated fracture is rare. We present here a 21-year-old man who sustained open posteromedial dislocation of the left ankle without malleolar facture when he jumped and sprained his right ankle while playing basketball. The most likely mechanism is forced flexion applied to the ankle joint leading to a rupture of the anterior capsule and lateral structures of the ankle followed by an accelerating inversion stress leading to a posteromedial dislocation of the talus from the tibial condyle. Transient paresthesia was noted in the area of the superficial peroneal nerve. At surgery, the anterior part of the tibiotalar joint capsule and anterior talofibular ligament were detached from their original sites. The calcaneofibular ligament was also detached with its associated periosteum and a tiny avulsed bony fragment. The articular facets of the tibia and talus were intact. The treatment consisted of wound irrigation, debridement, reduction and capsular suture followed by immobilization with a short leg cast. About 10 degrees of loss in the range of dorsiflexion was observed. The patient achieved good long-term functional results.