Hiroyuki Nagasawa

Learn More
BACKGROUND In the treatment of grade 1 chondrosarcoma of long tubular bones, a wide excision with replacement by a metal prosthesis has been widely used. However, postoperative function of the affected extremity has occasionally been problematic. CASE REPORT In two cases of grade 1 chondrosarcoma, a 54-year-old man with a lesion in the mid humerus and a(More)
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(More)
Discal cyst is a lumbar intraspinal cyst communicating with intervertebral disc, and previously reported series described the wall of these cysts as consisting of dense fibrous connective tissue. We report a 29-year-old Japanese male with discal cyst showing unusual histological features. Clinical symptoms in the current case as well as imaging features(More)
OBJECTIVE This study describes a unique case of bilateral stress fractures of the fibulae and provides a literature review. CLINICAL PRESENTATION AND INTERVENTION A 16-year-old female badminton player presented with pain around the bilateral distal lateral legs. She had mild bilateral varus deformity at the knee joint, and the bilateral ankles showed(More)
We report a rare case of Langerhans cell histiocytosis involving the sternum. The patient was a 12-year-old girl presenting with anterior chest pain and swelling. Radiographs and computed tomography showed an osteolytic lesion in the sternum. Technetium bone scintigraphy revealed increased uptakes in the sternum, the greater trochanter of the right femur,(More)
BACKGROUND Cyclooxygenase-2 (COX-2) is a key enzyme in the conversion of arachidonic acid to prostanoids, and its activation is associated with carcinogenesis as well as inflammation. The antitumor effect of selective COX-2 inhibitors has been noted in various malignancies. Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue(More)
Retinoic acid (RA) plays an important role in bone metabolism in vivo through osteoclast activation and bone resorption. Retinoid X-activated receptor beta (RXRbeta) has been implicated in the genetic spinal defect of ossification of the posterior longitudinal ligament (OPLL). In this study, we examined the effects of 9-cis RA and all-trans RA (ATRA) on the(More)
A 34-year-old woman complained of pain and swelling in the left patella. Because of roentgenogram showed hardly any destruction of the patella, she was not initially treated for a bone tumor. The clinical course followed the initial symptoms of a respiratory disorder with pulmonary metastatic foci. A bone tumor was first suspected after aspiration cytology(More)
In this report, we present a 68-year-old man with rice body formation in the flexor tendon sheath of the fingers without any inflammatory diseases such as tuberculosis or rheumatoid arthritis. The patient visited our institute in March 2004 with a one-month history of swelling and pain of the right distal forearm. Laboratory data were within normal limits,(More)