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Y Ubayama

Publications and source records attributed to Y Ubayama.

At least 19 recordsLinked to original sources
PubMed2001

Destruction of acetabular bone caused by early failure of a constrained acetabular component.

Use of a constrained acetabular component is 1 option for the treatment of dislocation after total hip arthroplasty. We report a case of a constrained acetabular component that resulted in postoperative early fixation loss and required revision 12 days after primary surgery. The superoposterior wall of the acetabulum was destroyed by the migrated acetabular component. Sharp ends of screws with a metal shell may have plowed up acetabular bone gradually after fixation loss of the component. This failure illustrates the potential risk of using a constrained acetabular component for total hip arthroplasty.

Acetabulum↗
PubMed1996

Hyperplastic callus formation in both femurs in osteogenesis imperfecta.

A 3-year-old boy with osteogenesis imperfecta had hyperplastic callus formation in the right femur, without preceding trauma or fracture. Radiologically, this bony mass in the femoral shaft mimicked osteosarcoma. Open biopsy showed that it was benign and suggested hyperplastic callus formation. Seven months after the biopsy, the hyperplastic callus had practically vanished. A similar process developed in the left femur 1 year later, also without fracture.

Bony Callus↗
PubMed1992

Primitive neuroectodermal tumors of bone and soft tissue. With reference to histologic differentiation in primary or metastatic foci.

Primitive neuroectodermal tumors (PNET) of the bone and soft tissue were reviewed by immunohistochemistry and partly by morphometry, focusing particularly on histologic changes in recurrent or metastatic foci, in order to elucidate their probable histogenetic relationship with Ewing's sarcoma (ES) and its extraskeletal counterpart (EES). Eleven cases of bone tumor (average patient age; 15.1 yr) and 12 cases of soft tissue tumor (average patient age; 22.1 yr) which disclosed unequivocal Homer-Wright rosettes and/or at least foci of ganglion cell differentiation either in a given primary tumor or metastatic (or recurrent) foci were selected from small round cell tumors primarily categorized as ES or EES. Most of the cases for which follow-up biopsy samples were available disclosed prominent Homer-Wright rosettes in the metastases, whereas the primary tumors showed features of ES and lacked rosettes. In only one case, Homer-Wright rosettes were absent in the metastatic tumor. Most cases had been treated by combined intensive chemotherapy and radiotherapy, which might have influenced cell differentiation. Neural markers (neuron-specific enolase, neurofilament protein and others) were positive in most cases. Three cases with otherwise typical histologic features of ES or EES showed minute foci of ganglion cell differentiation, as confirmed by morphometry and neural markers. These results suggest that ES (or EES) and PNET are histogenetically related, but represent different stages of cell differentiation.

Adolescent↗
PubMed1990

[Adjuvant chemotherapy of osteosarcoma].

Osteosarcoma is the one of the tumors that's prognosis have been improved dramatically by the introduction of chemotherapy consisting mainly of adriamycin, high-dose methotrexate with Leucovorin rescue and cisplatinum. Now, the purpose of the treatment for osteosarcoma are assurance of their life and functional and beautiful limb-sparing. Recently, preoperative chemotherapy for limb saving is given to patients with osteosarcoma of the extremities. The five year survival rate increased to 65% and limb sparing rate became above 50%. It is generally accepted that pre- and post-operative chemotherapy can inhibit pulmonary micro metastasis and prove to be of great significance in improving the survival rate of patients with osteosarcoma of extremities and achieve limb salvage operation.

Adult↗
PubMed1988

The alteration in the pattern of pulmonary metastasis with adjuvant chemotherapy in osteosarcoma.

Alterations in the pattern of pulmonary metastasis of patients with osteosarcoma treated with adjuvant chemotherapy were studied. Thirty two patients who were treated with both radical surgery and adjuvant chemotherapy were observed (chemotherapy group). As a control, sixty two patients treated with radical surgery alone were also assessed (non-chemotherapy group). The chemotherapy group demonstrated a reduction in the number and a delay in the appearance of metastases. The tumour doubling time did not differ between the chemotherapy and non-chemotherapy groups. The initial site of metastasis among the chemotherapy group was most commonly in the lower lung field, whereas among the non-chemotherapy group it was usually to the middle lung field. The chemotherapy group survived longer than the non-chemotherapy group after developing pulmonary metastases. Histological examination showed that the metastatic foci stimulated the primary sites.

Adolescent↗
PubMed1988

[Efficacy and problems of radio- and chemo-combination therapy for malignant bone tumors].

In this study we reviewed cases of osteosarcoma, malignant lymphoma of bone and Ewing's sarcoma. Historically, osteosarcoma was unresponsive to chemotherapy. Most patients were treated by radiation or amputation alone and 80% of them died from pulmonary metastasis within 2 years. Five-year survival rate was 13%. Introduction of ADM, HD-MTX and CDDP improved dramatically the prognosis of these cases. Five-year survival rate was 60%. On the other hand, 11 cases of malignant lymphoma of bone and 4 cases of Ewing's sarcoma were treated by radiation with no local recurrence. VEPA or CHOP chemotherapy was used for the former with a five-year survival rate of 45%. For the latter, T-11 protocol (Rosen) was applied, and all patients survive with no metastasis. Other organ injuries circulatory disturbance, bone necrosis and growth-disturbance of bone in radiotherapy, myocardiopathy caused by ADM and renal toxicity of CDDP are all problematic.

Adolescent↗
PubMed1988

[Operative treatment of bone and soft tissue tumors involving pelvic region, especially retroperitoneal area including lumbar region].

During the past 17 years, 35 of 60 patients with malignant bone and soft tissue tumors of the pelvic and surrounding tissues, were treated surgically. There were 13 bone tumors and 22 soft tissue tumors, There were 12 recurrent cases and 23 non-recurrent cases with cumulative 5-year survival rates of 20% and 70%, respectively. In the tumors involved even in the iliolumbar area, curative resection was difficult with poor prognosis. Serious complications also developed with high incidence immediately after operation, including ileus, severe infections and postoperative bleeding. When the affected limb was preserved, many difficulties were encountered in functional recovery. Therefore, we combine preoperative radiation and intra arterial infusion for the prevention of recurrence at the resection margin. However, we have not obtained completely satisfying results. Operations involving these tumors should be performed in cooperation with other fields.

Bone Neoplasms↗
PubMed1987

[A case of malignant paraganglioma arising from the retroperitoneum].

We report the case of 38-year-old male with a malignant and functional paraganglioma arising from the retroperitoneum. He was admitted to our hospital with a pathological fracture of the right femur, A diagnosis of paraganglioma was made after taking a biopsy specimen and discovering a hypervascular retroperitoneal tumor. The level of catecholamine in his urine was greatly increased, accompanied with hypertension, rapid pulse and sweating. He was treated with chemotherapy, radiotherapy and surgical therapy. However, he died from pulmonary metastasis.

Adult↗
PubMed1987

[Analysis of liposarcoma].

Liposarcoma is one of the most common soft tissue sarcomas, ranking with rhabdomyosarcoma and malignant fibrous histiocytoma. We have treated 47 cases of liposarcoma, comprising 35 males and 12 females ranging in age from 22 to 86 years, with a median age of 56 years. The most common site of primary tumor was the thigh, the most common primary tumor stage by the UICC classification was T2, and the most common histological subtype by the WHO classification was myxoid type. Xerography, CT and angiography are useful forms of examination for diagnosis before surgery. Naked eye findings of the tumor often show a lobular or nodular growth pattern. Surgical therapy for the primary tumor, especially curative wide resection (by the method of Kawaguchi, et al.) is most effective for preventing local recurrence. Radiotherapy is not as effective as for rhabdomyosarcoma and chemotherapy should be applied for occult micro-metastases. Ten of the 47 cases died due to distant metastases and the 5 year survival rate was 76.2%.

Adult↗
PubMed1987

[Chemotherapy using cisplatin in bone and soft tissue sarcoma].

Cisplatin was used in 14 bone and soft tissue sarcomas. Severe vomiting developed in all cases, but the duration was relatively short. Renal function was disturbed in cases with a higher total dose. This side effect was considered to be the dose-limiting factor of cisplatin. Seven cases showed high-frequency deafness but they did not complain of disturbance during conversation. In seven metastatic osteosarcomas, one was evaluated as a partial response and one as a minor response. No response was observed among three soft tissue sarcomas. Three cases of osteosarcoma receiving cisplatin in adjuvant chemotherapy have been disease-free for 4 and 46 months after resection of pulmonary metastases and for 50 months after resection of the primary tumor. We consider cisplatin to be the first-choice drug in cases resistant to adriamycin or methotrexate, but there are some problems when cisplatin is used in adjuvant chemotherapy, because of its side effects.

Adolescent↗
PubMed1987

[Significance of surgical adjuvant chemotherapy in osteosarcoma].

The primary site of the metastasis of osteosarcoma is the lung. More than 90% of patients have died of pulmonary metastasis in one to two years. Control of osteosarcoma depend upon the prevention of its pulmonary metastasis. The introduction of chemotherapy consisting mainly of Adriamycin, high-dose methotrexate with Leucovorin rescue and Cisplatinum, dramatically improved the prognosis of osteosarcoma. In the past, when systemic chemotherapy was not available, the five-year survival rate was around 19%. In patients who receive chemotherapy with the current combination of chemotherapeutic agents (ADM, HD-MTX, VCR, CPM, CDDP), the incidence of pulmonary metastasis was low, and the five-year survival rate increased to 65%. In patients who receive chemotherapy, pulmonary metastasis may be either delayed, with a single metastasis appearing after termination of treatment (late isolated type), or early and multiple, emerging in reaction to treatment (early multiple type). It is generally accepted that post-operative chemotherapy can inhibit pulmonary micro metastasis and prove to be of great significance in improving the survival rate of patients with osteosarcoma of extremities and achieve limb salvage operation. On the other hand, effective control of the side effects of drug administration such as nausea, vomiting, alopecia, cardio (ADM) and renal (CDDP) toxicity and bone marrow suppression, is a problem that must be solved as soon as possible.

Adolescent↗
PubMed1987

[A case report of malignant schwannoma originating from the bone].

While malignant schwannoma is encountered frequently as soft tissue sarcomas, it rarely is found to originate in the bone. We have had a case of malignant schwannoma originating from the tibia of a 47-year-old man. He died from uremia, that resulted from lung, spinal vertebral body, and lymph nodes metastases, despite surgical treatment and chemotherapy. In cases of rare bone tumors, the clinical diagnosis of tumoral manifestations originating in the bone is more important than the histopathological diagnosis.

Bone Neoplasms↗
PubMed1986

Clear cell chondrosarcoma. A report of two cases and review of literature.

Two cases of clear cell chondrosarcoma located in the distal femur and proximal humerus are reported. Both patients were men aged 35 and 51 years. Their initial symptom was a pathologic fracture. Roentgenographically, one patient showed a purely lytic lesion and another lytic with centrally radiodensity. Microscopic examination revealed that the tumor cells have a centrally placed vesicular nucleus surrounded by a clear cytoplasm, with distinct boundaries. Their cytoplasm stained with S-100 protein by the peroxidase-antiperoxidase method. We found 36 reported cases (including the two reported here), and delineated the clinico-pathologic characteristics of the disease.

Adult↗
PubMed1986

[Massive osteoplastic bone metastasis of hepatocellular carcinoma--a case report].

Massive osteoplastic bone tumor in hepatocellular carcinoma is very rare. A 48-year-old man was misdiagnosed as osteosarcoma of the right proximal tibia with dense sclerosis and marked periosteal spiculation. Histologically, there were many osteoids and immature trabeculi. Tumor cells with spindle nuclei were not atypical and had few mitoses. Three years later, he suddenly died of rupture of cerebral aneurysm. Autopsy revealed small hepatocellular carcinoma with distant metastases of the tibia, lumbar spine and lung. In this case, it was extremely difficult to decide whether or not we were dealing with primary malignant tumor.

Bone Neoplasms↗
PubMed1986

[Childhood liposarcoma of the eyelid--a case report].

An 11-year-old girl noted a small mass on the left upper eyelid. The tumor was excised and diagnosed as round cell-type liposarcoma. In spite of intensive multimodal therapy, the tumor tended to recur, metastasizing to the central nervous system and soft tissues. The patient died of progressive disease three years after diagnosis. Features unique to this case include the ophthalmological primary site, the age at onset, the histological subtype and the mode of metastasis.

Brain Neoplasms↗
PubMed1985

[A histological study on osteosarcoma. Part II: The mode of local extension of osteosarcoma].

The survival rate of patient with osteosarcoma has been increasing, owing to the development of adjuvant chemotherapy. Recently, the limb saving procedure in osteosarcoma has been attempted in many countries. Although we need knowledge about the mode of local extension of osteosarcoma in the planning of this surgery, there are few reports concerning the matter. The purpose of this paper is to make clear, morphologically, how tumor tissue extends across the epiphyseal plate, periosteum and bone marrow. The materials were 26 amputated extremities of osteosarcoma which had not received any chemotherapy or radiotherapy. Paraffin embedded macrosections were prepared and stained with HE and Masson stain. When epiphyseal plate was open or closing, 13 out of 14 cases (93%) showed transphyseal extension of tumor. Tumor extension along the vessels at the center of the plate and the epiphyseal artery was most common. Transmedullary extension showed three different types, infiltrative type (18 cases), lobular type (5 cases), and "skip" type (one case). None had capsule or pseudocapsule surrounding the tumor. As to the relationship between periosteal reaction and tumor involvement of cortex or medulla, periosteal reaction was located more proximally than cortical or medullary involvement in some cases. In other cases, however, cortical or medullary involvement was located more proximally than periosteal reaction. The gaps between the tips of the periosteal reaction and cortical or medullary involvement ranged from 0.5 to 1.5 cm. In the transperiosteal extension, it was confirmed that tumor cells had invaded the periosteum along the vessels penetrating the periosteum.

Adolescent↗
PubMed1984

[Four case reports of sarcoma combined with carcinoma].

We report 4 cases of double cancer, combined sarcoma and carcinoma. Case 1 was a 50-year-old woman, had a malignant fibrous histiocytoma in the leg and an advanced gastric carcinoma. The soft tissue sarcoma was resected and the gastric carcinoma was treated with chemotherapy. She died from pulmonary metastasis from the sarcoma. Case 2 was a 72-year-old woman with a liposarcoma in the leg and a thyroid carcinoma. Both tumors were resected, however, she died from pulmonary metastasis from the carcinoma. Case 3 was a 65-year-old man with a liposarcoma in the buttock and lung carcinoma. Both tumors were resected and he is alive and disease-free. Case 4 was a 47-year-old man with spindle cell sarcoma of the tibia and a rectal carcinoma. Both tumors were treated surgically, but he died from pulmonary metastasis from the sarcoma. We suggest that the combination of sarcoma and carcinoma is very rare and that the prognosis in these cases is very poor.

Adenocarcinoma↗