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Kyoji Okada

Publications and source records attributed to Kyoji Okada.

At least 37 records · Page 2Linked to original sources
PubMed2004

Second primary osteosarcoma with rosette-like structure in a patient with retinoblastoma.

A Japanese male patient developed bilateral retinoblastomas at the age of 1 year, but remained continuously disease-free after enucleation of the left eye and radiation therapy to the right eye. He noticed a painless hard mass around the right temporal bone when he was 25 years old. Biopsy specimen showed a small multi-nodular proliferation of tumor cells with prominent rosette-like structures. Eosinophilic material with focal mineralization was seen in the center of the rosettes. Immunostaining of the tumor cells showed positive reactions for epithelial membrane antigens CD 56 and CD 99. The patient was treated with systemic chemotherapy, and the tumor partially diminished. It is well known that a few osteosarcomas show a rosette-like appearance with production of osteoid in the center, but this is the first case of second primary osteosarcoma with prominent rosette-like features.

12E7 Antigen↗
PubMed2004

Nodular fasciitis of the finger.

Nodular fasciitis is a benign reactive lesion, often mistaken for a soft tissue sarcoma in clinical practice. Involvement of the finger is very rare and, as a result, in this location the lesion has sometimes been treated by ray amputation because of misdiagnosis. We report on the clinical and histological features of nodular fasciitis in a 30-year-old man who was treated by excisional biopsy. There has been no evidence of local recurrence at the recent follow-up 8 years after surgery. The importance of careful histological examination to avoid radical surgery should be emphasized because marginal excision can provide good results in the treatment of nodular fasciitis.

Adult↗
PubMed2004

Stress fracture of the second metacarpal bone.

Stress fractures are usually encountered in athletes; however, only eight such cases involving the metacarpal bones have been reported in the English literature. We report on the rare case of a 15-year-old female tennis player with a stress fracture of the second metacarpal bone.

Adolescent↗
PubMed2004

Osteosarcoma occurring in osteogenesis imperfecta.

We describe a case history of a 24-year-old male with osteogenesis imperfecta (OI) who developed osteosarcoma of the left thigh. High-dose ifosfamide therapy caused marked tumor regression of multiple lung metastases. Immunohistochemically, the tumor cells were diffusely positive for the p53 protein. Mutation of the p53 gene was not detected by direct genomic sequencing of exons 4-8. The radiographic characteristics, including irregularly distributed osteolytic lesions and cortical discontinuity, should not be confused with hyperplastic callus formation, a benign process. A biopsy is critical to establish the differential diagnosis between osteosarcoma and common hyperplastic callus formation in OI; however, it must be applied with great care.

Adult↗
PubMed2004

Skeletal muscle metastases of carcinoma: a clinicopathological study of 12 cases.

OBJECTIVE: To clarify the clinical and magnetic resonance (MR) imaging features of a rare condition of metastasis of carcinoma to skeletal muscle. METHOD: Clinicopathological findings for 12 patients (10 male, two female, age range 48-89 years, mean age 68 years) with skeletal muscle metastases of carcinomas were reviewed retrospectively. RESULTS: In nine of the 12 patients the skeletal muscle metastasis was presented as "painful mass". The lung was found to be the most common primary source, accounting for 33% of the cases, and the lower extremity was the most common metastatic site, accounting for 67% of the current series. Diagnosis was made by biopsy in all cases. Overall, MR images were not specific, but on the gadolinium-DTPA enhanced MR images, extensive peritumoral enhancement associated with central necrosis was found in 11 of the 12 patients (92%). Seven patients died within 2-19 months (average: 9 months) after the detection of the skeletal muscle metastasis, among whom only one patient was continuously disease free for 92 months after wide excision of the metastatic lesion. CONCLUSION: Skeletal muscle metastasis is often presented as a painful mass in patients with known primary carcinoma. For diagnosis, needle biopsy is mandatory. However, a painful mass with an extensive peritumoral enhancement should be highly suspected to represent carcinoma metastasis to skeletal muscles. In selected patients, wide excision with combined chemotherapy could yield unexpectedly good results.

Aged↗
PubMed2004

Good outcome for infant of mother treated with chemotherapy for ewing sarcoma at 25 to 30 weeks' gestation.

There have been only three previous reports of women with Ewing sarcoma who received chemotherapy while pregnant. A 17-year-old woman with Ewing sarcoma was treated with a combination of doxorubicin (Adriamycin) and ifosfamide during the 25th to 30th week of gestation, and the baby was delivered at the 32nd week. The baby was developing normally at follow-up at 8 months of age. This case report supports the idea that in this situation, the pregnancy can be continued to await fetal growth, and second-trimester chemotherapy may not have a deleterious effect on the fetus.

Adolescent↗
PubMed2004

Enhanced antitumor activity of ultrasonic irradiation in the presence of new quinolone antibiotics in vitro.

To determine if there is any synergistic antitumor effect of ultrasound (US) in the presence of new quinolone (NQ) antibiotics, 0.2 mM solutions of lomefloxacin hydrochloride (LFLX), sparfloxacin (SPFX), ciprofloxacin hydrochloride (CPFX), and gatifloxacin hydrate (GFLX) were tested as sonodynamic agents against sarcoma 180 cells in vitro. After US irradiation at 2 W/cm(2) for 30 and 60 s, the survival rates of tumor cells in the presence of NQ antibiotics were significantly lower than those in their absence (P < 0.001). In May-Giemsa smears, most of the tumor cells remained intact in the control group. However, in the 0.2 mM SPFX group, the tumor cells were mostly fragmented. The synergistic antitumor effect of SPFX was dose-dependent. Furthermore, when D-mannitol was used with SPFX, the survival rate of tumor cells after irradiation was comparable with that when SPFX alone was applied, but when L-histidine was used concurrently, the survival rate of tumor cells was significantly higher than that when SPFX alone was applied. These findings suggest that NQ antibiotics would exhibit useful antitumor activity under US irradiation, and that generation of singlet oxygen is involved in the process of cell damage.

Animals↗
PubMed2004

Osteosarcomas after the age of 50: a clinicopathologic study of 64 cases--an experience in northern Japan.

BACKGROUND: The clinicopathologic profile and prognostic factors of osteosarcomas after the age of 50 years have been obscure. METHODS: Clinicopathologic features were analyzed in 645 patients with osteosarcoma who were registered at the Tohoku Musculoskeletal Tumor Society and National Cancer Center in Tokyo between 1972 and 2002. RESULTS: Sixty-four patients (9.9%; 34 men and 30 women) were more than 50 years old. The most common location was the distal femur (n = 13), followed by the pelvis (n = 10), proximal femur (n = 9), and proximal fibula (n = 6). Seven (11%) patients had lung metastasis at initial presentation. On radiographs, an osteolytic appearance without periosteal reactions was a common and characteristic feature. Forty-eight tumors (75%) were classified as conventional osteosarcomas. Fourteen cases (22%) were secondary; postradiation osteosarcoma was most common in these patients, but there was no Paget's sarcoma. At the initial presentation, misdiagnoses without biopsy were made in 15 (23%) of the 64 cases. Preoperative chemotherapy was given to 22 patients, but the effect was poor in 18 cases (82%). Fifty-four patients underwent surgery, whereas the other 10 patients were treated without surgery because of systemic or inoperable local conditions. The overall survival rate at 5 years was 55.5%. Multivariate analysis showed initial pulmonary metastasis, axial tumor location, and larger tumors as significant prognostic factors. CONCLUSIONS: In northern Japan, most patients with osteosarcoma after the age of 50 had primary osteosarcoma. Careful radiological examination and biopsy are mandatory for correct diagnosis. Current systemic chemotherapy is not effective for this age group. Alternative treatment strategies should be considered.

Age of Onset↗
PubMed2003

Multicentric osteosarcoma with long-term survival.

We present a 14-year-old girl with multicentric osteosarcoma who has survived for over 9 years to date. The patient first noticed right knee pain in 1992. Radiographs showed a destructive and sclerotic lesion of the right distal femur. Similar small sclerotic lesions were seen in the proximal metaphysis of the right femur, proximal site of the right humerus, and mid-posterior of the left humerus. A diagnosis of multicentric osteosarcoma was made on a biopsy of the right distal femur. The sclerotic lesions of the bilateral humeri disappeared after systemic chemotherapy (T-20), and thus wide excisions of the right distal femur and proximal femur were performed in 1993. New lesions appeared in the left iliac bone and the first lumbar vertebra on bone scintigraphy 24 months after the first surgery. Chemotherapy and wide excisions of the left iliac bone and the first lumbar vertebra were performed. The patient was well at the latest follow-up in April 2003, with no evidence of local recurrence or distant metastasis, but recently renal dysfunction appeared.

Adolescent↗
PubMed2003

Tetraparesis caused by chondroblastoma of the cervical spine: a case report.

STUDY DESIGN: A chondroblastoma of the posterior component of the seventh cervical vertebra with tetraparesis was reported. Imaging studies showed an expansile destructive lesion with mineralization. OBJECTIVES: To emphasize the occurrence of tetraparesis caused by chondroblastoma in the cervical spine. SUMMARY OF BACKGROUND DATA: Chondroblastoma is a rare benign neoplasm of the bone. Only eight cases of chondroblastoma occurring in the vertebra are reported in the literature, including five in the cervical vertebrae. However, there was no reported case of tetraparesis in the literature. METHODS: A 19-year-old man had a tetraparesis caused by chondroblastoma of the posterior component of the seventh cervical vertebra, which invaded the vertebral body with an extraosseous involvement. Imaging studies showed an expansile destructive lesion with mineralization. Curettage of the lesion was performed from both anterior and posterior approaches. The defect of the vertebral body was reconstructed by autologous iliac bone graft with posterior fusion using the Luque instrumentation system. RESULTS: Histologically, the tumor cells were forming cartilage with round or oval nuclei, which often were indented or had a longitudinal groove. There was no sign of local recurrence, and the neurologic deficit had fully recovered 2 years and 3 months after surgery. CONCLUSIONS: Chondroblastoma should be included in the differential diagnosis of lytic expansile destructive lesion of the spine, although there is an extraosseous involvement. Prompt adequate surgery should be performed as soon as possible after establishment of the correct histologic diagnosis to restore the neurologic deficit.

Adult↗
PubMed2003

Dendritic cell and effector cell infiltration in soft tissue sarcomas with reactive lymphoid hyperplasia.

The lymph node is the site of antigen presentation, and dendritic cells are sentinels for anti-tumor immunity. However, little is known about the histological features of lymph nodes and dendritic cells in soft tissue sarcomas. The reactive lymph node and infiltration of dendritic cells or effector cells were studied histologically in 10 soft tissue sarcomas with reactive lymphoid hyperplasia. The cases included four malignant fibrous histiocytomas, two malignant peripheral nerve sheath tumors, one synovial sarcoma, one epithelioid sarcoma, one malignant granular cell tumor, and one liposarcoma. The proportions of the T zone, lymphoid follicle, and lymphoid sinus (which was occupied by cells immunopositive for antibodies against CD3, CD20, or CD68) were 33.4% +/- 11.0%, 6.1% +/- 4.9%, and 13.5% +/- 6.5%, respectively. T zone hyperplasia was observed in all cases, and sinus histiocytosis was found in four. The proportion of the T zone in regional lymph nodes of soft tissue sarcoma patients was significantly higher than that in adult autopsy cases without a cancer history. CD8-, TIA-1-, or granzyme B-positive effector cells were found in each sarcoma tissue. Whereas CD1a-positive dendritic cells were not detected, S-100 protein-positive or CD83-positive dendritic cells were observed in five sarcoma tissues. The coefficient correlation between the numbers of effector cells and dendritic cells positive for CD83 or S-100 protein were demonstrated. Although this is a preliminary report, the present study demonstrated that some soft tissue sarcoma patients showed reactive lymphoid hyperplasia. Furthermore, the association between the infiltration of dendritic cells and that of effector cells was observed in patients with soft tissue sarcomas.

Adolescent↗
PubMed2003

Osteoporotic vertebral fracture adjacent to a nonsegmented hemivertebra.

A combination of osteoporotic vertebral fractures and congenital spinal deformity is theoretically possible, but there have been no reports on this combination in the literature. We describe a rare case of an osteoporotic vertebral fracture adjacent to the nonsegmented hemivertebra. A 60-year-old postmenopausal woman who did not recall any specific trauma presented with severe back pain. She had markedly decreased bone mineral density and significant lumbar kyphoscoliosis with a nonsegmented hemivertebra between L1 and L2 on radiographs of the lumbar spine. Magnetic resonance imaging (MRI) revealed a vertebral fracture adjacent to the nonsegmented hemivertebra. Laboratory studies showed increased serum bone-specific alkaline phosphatase (BAP) and urinary type I collagen crosslinked N-telopeptide (NTx). A thoracolumbar brace was applied for 3 months. Daily administration of alendronate normalized her serum BAP and urinary NTx levels. MRI scans of the lumbar spine after 6 months also confirmed normalized signal intensities of the fractured vertebra adjacent to the nonsegmented hemivertebra. The vertebral fracture seemed to be induced by spinal malalignment, increased stress on the adjacent level of the fused segment, and its fragility due to osteoporosis.

Bone Malalignment↗
PubMed2003

Congenital pseudoarthrosis of the tibia treated with low-intensity pulsed ultrasound stimulation (LIPUS).

A 16-year-old Japanese boy was admitted to our institution in September 2000 because no apparent callus had appeared around a fracture after 6 weeks of cast fixation. Physical examination revealed a tenderness of the right lower leg, and multiple small subcutaneous tumors and café-au-lait spots in extremities and trunk. Radiographs showed the fracture of the right lower tibia with bony sclerosis and a localized fusiform osteolytic lesion at the fracture site. The affected tibia bowed anteriorly and the medullary space in the lower tibia was narrow. A diagnosis of Boyd type IV congenital pseudoarthrosis of the tibia was made. Treatment with low-intensity pulsed ultrasound (US) stimulation (LIPUS) was administered for 20 min/day, and a nonweight-bearing gait was continued with a cast or brace fixation. At 6 months after the treatment, a small amount of bridging callus was seen. We continued the treatment for 1 year until the solid fusion was observed on radiographs and the patient started full-weight-bearing.

Adolescent↗
PubMed2003

Factors related to long-term outcome after decompressive surgery for ossification of the ligamentum flavum of the thoracic spine.

OBJECT: Factors related to long-term surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum (OLF) have not been fully investigated. To evaluate these factors, the authors reviewed medical records obtained in patients who had undergone decompressive surgery for thoracic OLF. METHODS: Thirty-four patients in whom decompressive surgery was performed for thoracic OLF (mean follow-up period 8 years) were recruited. Fourteen patients underwent simultaneous decompressive surgery for cervical or lumbar lesions. Patient age, duration of symptoms, OLF type, dural adhesion, neurological status classified by the Japanese Orthopaedic Association (JOA) scale before and after surgery (1 month postoperatively and at final follow up), and recovery rate were reviewed. The ossified ligamentum flavum was classified into five types according to Sato's classification by assessing preoperative computerized tomography scans. The mean preoperative JOA score (5) was significantly improved at 1 month after surgery (7.1) and at final follow up (7.9) (p < 0.05). Recovery rates at 1 month and at final follow up were 34.6 and 44.2%, respectively. No significant correlations were found between age, OLF type, and neurological status before and after surgery. In patients with dural adhesion, which was observed in cases of larger-type OLF (p < 0.02), lower JOA scores were observed compared with those in patients without dural adhesion both preoperatively and at 1 month after surgery (p < 0.05) but not at the final follow-up examination. Higher JOA scores and recovery rates were demonstrated in patients who had undergone simultaneous surgery than in those who had not undergone simultaneous surgery at 1 month (p < 0.05) but not at the final follow up. Using multiple regression analysis, the authors identified the duration of preoperative symptoms as the most important predictor of a high JOA score and recovery rate at the final follow up. CONCLUSIONS: Duration of preoperative symptoms represents the most important predictor of long-term surgery-related outcome in patients treated for thoracic OLF. The type of ossified ligamentum flavum, dural adhesion, and simultaneous surgery for coexistent cervical or lumbar lesions do not appear to influence the long-term postoperative prognosis.

Adult↗
PubMed2002

A low-grade extraskeletal osteosarcoma.

The case of a 35-year-old woman with low-grade extraskeletal osteosarcoma of the left leg is presented. Radiographs showed peripheral ossification of the lesion, suggesting myositis ossificans. Most of the tumor was composed of cartilage, and the cellularity and cell atypia of the proliferating chondrocytes were mild to moderate. In the periphery, bone formation with a relatively clear margin and proliferation of spindle cells with minimal nuclear atypia were observed. The average percentage of cells positive for MIB-1 was 9.0%. A diagnosis of low-grade extraskeletal osteosarcoma was made on the basis of these histologic findings. The clinical course 47 months after a wide excision was uneventful.

Adult↗
PubMed2002

Unusual variant of liposarcoma with multiple punctate calcifications.

We report a case of liposarcoma in a 17-year-old boy in which both the radiographs and histology demonstrated multiple punctate calcifications. In addition, this unusual variant consisting of myxoid, round cell and well-differentiated liposarcoma behaved aggressively resulting in the death of the patient.

Adolescent↗
PubMed2002

Leiomyosarcoma of the lumbar spine: case report.

STUDY DESIGN: A primary leiomyosarcoma in the L2 vertebral body without any neurologic deficit is reported. The radiologic diagnosis was a metastasis, and the histologic diagnosis was confirmed by transpedicular needle biopsy. OBJECTIVE: To emphasize the occurrence of primary leiomyosarcoma in the lumbar spine. SUMMARY OF BACKGROUND DATA: Leiomyosarcoma is a rare malignant neoplasm of the bone, and only one report of the primary spinal tumor exists. In the case of leiomyosarcoma of the bone, metastasis, most commonly of the uterus or gastrointestinal tract, must be carefully ruled out before the diagnosis of primary leiomyosarcoma in the bone is confirmed. METHODS: Leiomyosarcoma of the second lumbar vertebra in a 47-year-old woman with no neurologic deficit is reported. Imaging findings indicated a nonspecific high-grade lesion. A total spondylectomy of L2 with en bloc excision of the lower half of L1 and the upper third of L3 vertebral bodies was performed after preoperative radiation therapy. The defect of the vertebral body was reconstructed by titanium mesh cage, and T11 to S1 vertebrae were instrumented by the pedicle screw and rod system. RESULTS: The surgical margin was marginal. Histologically, the tumor cells were elongated, with abundant cytoplasm and cigar-shaped nuclei, showing proliferation in fascicles and bundles. No sign of local recurrence or metastasis was evident 2 years and 1 month after surgery. CONCLUSIONS: Leiomyosarcoma should be included in the differential diagnosis of spindle cell tumor of the spine, and it should be confirmed or excluded by immunohistochemical and/or ultrastructural studies. If the expected surgical margin is definitive, a total en bloc spondylectomy should be performed.

Diagnosis, Differential↗