Ikuo Fujita

Solitary fibrous tumor in the extremity: case report and review of the literature.

A solitary fibrous tumor is a relatively unusual neoplasm first described as a distinctive tumor arising from pleura. Some reports have shown that solitary fibrous tumors also affect extrathoracic regions. The current study presents a literature review with four additional patients with solitary fibrous tumor arising from the extremities to clarify clinicopathologic features. The current four patients were two males and two females, ranging from 17 to 60 years of age. Magnetic resonance imaging scans of the current patients showed inhomogeneous low to intermediate intensity signal on T1-weighted images and inhomogeneous intermediate to high intensity signal on T2-weighted images. Histologically, the tumors were composed of a haphazard proliferation of spindle cells, although cellularity was variable in each case. Two of the four tumors showed hypercellularity of spindle cells with focally myxomatous or hyaline changes, whereas myxomatous patterns with scattered spindle cells throughout the specimens were observed in the other two tumors. Immunohistochemically, all four patients showed positive immunoreactivity for CD34, and two tumors showed focally positive immunoreactivity for bcl-2 protein. During the followup of 12 to 54 months, neither local recurrence nor distant metastasis was detected after wide resection. Examination of the literature and the current patients suggests that solitary fibrous tumors in the extremities are likely to have a malignant potential, although most patients have a benign clinical course. Local wide resection and careful long-term followup are necessary for patients with solitary fibrous tumor in the extremities.

Pseudogout attack of the lumbar facet joint: a case report.

Study Design. A case of acute low back pain caused by pseudogout attack of the lumbar facet joint is reported. Objective. To report a new cause of acute low back pain previously unreported in the literature. Summary of Background Data. There have been some reports of lumbar spinal stenosis caused by calcium pyrophosphate dihydrate crystal deposition. However, there are no known reports of pseudogout attack of the lumbar facet joint. Methods. An axial magnetic resonance imaging scan demonstrated joint effusion at the level of the bilateral L4–L5 facet joint. Aspiration of the left L4–L5 facet joint yielded 1.5 mL of pus-like synovial effusion. Multiple cultures of synovial fluid tested negative for bacteria and fungi, whereas compensated polarized light microscopy revealed monoclinic or triclinic crystals with a positive birefringence. Results. The symptoms of acute low back pain lasted for 3 days. Local and systemic inflammatory signs, as well as symptoms, gradually improved after joint aspiration. A follow-up evaluation 8 months after lumbar facet joint aspiration showed complete resolution of pain and no neurologic deficit. Conclusions. Pseudogout attack of the lumbar facet joint is rare, but this clinical entity should be added to the differential diagnosis of acute low back pain.

Neural fibrolipoma of the superficial peroneal nerve in the ankle: A case report with immunohistochemical analysis

This report presents a case of neural fibrolipoma arising from the superficial peroneal nerve in the ankle. A 28‐year‐old woman was referred with a soft tissue mass in the anterior aspect of the right ankle, which had been gradually enlarging for the past 10 years. Magnetic resonance imaging showed a mass lesion, measuring approximately 8 × 3 × 2 cm, with high to partially low signal intensity on both T1‐ and T2‐weighted images. A band of low signal intensity within the lesion, which is indicative of coexistence with the tumor and the superficial peroneal nerve, could be detected on both T1‐ and T2‐weighted images. The patient underwent an excisional biopsy. The specimen microscopically consisted of nerve bundles and fibro‐fatty proliferation with abundant collagen fibers. Immunoreactivity for CD34 antigen antibody was detected in fibrous spindle cells. This is the first report to present an immunohistochemical profile of neural fibrolipoma. Neural fibrolipoma should be considered as a differential diagnosis when a lipomatous lesion is encountered in the foot or ankle as well as in the upper extremities.

Periosteal osteoblastoma of the distal femur.

Osteoblastomas located on the surface of the cortical bone, so-called periosteal osteoblastomas, are extremely rare. We report on a case of periosteal osteoblastoma arising from the posterior surface of the right distal femur in a 17-year-old man. Roentgenographic, computed tomographic, magnetic resonance imaging, and histologic features of the case are presented. Periosteal osteoblastoma should be radiologically and histologically differentiated from myositis ossificans, avulsive cortical irregularity syndrome, osteoid osteoma, parosteal osteosarcoma, periosteal osteosarcoma, and high-grade surface osteosarcoma. Although periosteal osteoblastoma is rare, this tumor should be included in the differential diagnosis of surface-type bone tumors.

Expression of Transforming Growth Factor β Isoforms and Their Receptors in Malignant Fibrous Histiocytoma of Soft Tissues

Purpose: Transforming growth factor β (TGF-β) is a multifunctional growth factor that variably affects proliferation, differentiation, and extracellular matrix formation. Little information is currently available on the TGF-β expression in malignant fibrous histiocytoma (MFH). The aims of the present study were to investigate the expression of TGF-β isoforms and their receptors in human MFH specimens. Experimental Design: The expression of TGF isoforms, and TGF-β receptors (TGF-βR1 and -βR2) were immunohistochemically evaluated in 43 paraffin-embedded MFH specimens. Furthermore, the correlation of the TGF-β and receptor expression with tumor proliferative activity assessed by MIB-1 indices was analyzed. Results: Positive immunoreactivity for TGF-β1, -β2, and -β3 was identified in tumor cells of 42, 40, and 38 of the 43 MFHs, respectively. In each TGF-β isoform immunostaining, the specimens were divided into two groups based on the number of positive tumor cells: those with low (<25%) and those with high (≧25%) immunoreactivity. There were no statistically significant differences in the MIB-1 indices between the two groups. Positive immunoreactivity for TGF-βR1 and -βR2 was identified in tumor cells of 36 and 24 of the MFHs, respectively. The specimens were divided into two groups based on their receptor expression patterns: those with both TGF-βR1- and -βR2-positive immunoreactivity (n = 23), and those with both or either TGF-βR1- and -βR2-negative immunoreactivity (n = 20). The MIB-1 indices in the both-TGF-βR1- and -βR2-positive group were significantly higher than those in the other group (P = 0.0102). There was no significant difference in pulmonary metastasis ratios between the two groups. Conclusions: These findings strongly suggest an association of the TGF-β ligand/receptor system with a significantly higher MIB-1 index in human MFHs. Investigation of the TGF-βR1 and -βR2 coexpression might be useful in predicting tumor behavior of MFHs.

Accumulation of MRI contrast agents in malignant fibrous histiocytoma for gadolinium neutron capture therapy

Neutron-capture therapy with gadolinium (Gd-NCT) has therapeutic potential, especially that gadolinium is generally used as a contrast medium in magnetic resonance imaging (MRI). The accumulation of gadolinium in a human sarcoma cell line, malignant fibrosis histiocytoma (MFH) Nara-H, was visualized by the MRI system. The commercially available MRI contrast medium Gd-DTPA (Magnevist, dimeglumine gadopentetate aqueous solution) and the biodegradable and highly gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared as MRI contrast agents. The MFH cells were cultured and collected into three falcon tubes that were set into the 3-tesra MRI system to acquire signal intensities from each pellet by the spin echo method, and the longitudinal relaxation time (T1) was calculated. The amount of Gd in the sample was measured by inductively coupled plasma atomic emission spectrography (ICP-AES). The accumulation of gadolinium in cells treated with Gd-nanoCPs was larger than that in cells treated with Gd-DTPA. In contrast, and compared with the control, Gd-DTPA was more effective than Gd-nanoCPs in reducing T1, suggesting that the larger accumulation exerted the adverse effect of lowering the enhancement of MRI. Further studies are warranted to gain insight into the therapeutic potential of Gd-NCT.

Boron neutron capture therapy for clear cell sarcoma (CCS): Biodistribution study of p-borono-l-phenylalanine in CCS-bearing animal models

Clear cell sarcoma (CCS) is a rare melanocytic malignant tumor with a poor prognosis. Our previous study demonstrated that in vitro cultured CCS cells have the ability to highly uptake l-BPA and thus boron neutron capture therapy could be a new option for CCS treatment. This paper proved that a remarkably high accumulation of (10)B (45-74 ppm) in tumor was obtained even in a CCS-bearing animal with a well-controlled biodistribution followed by intravenous administration of L-BPA-fructose complex (500 mg BPA/kg).

Evaluation of BPA uptake in clear cell sarcoma (CCS) in vitro and development of an in vivo model of CCS for BNCT studies.

Clear cell sarcoma (CCS), a rare malignant tumor with a predilection for young adults, is of poor prognosis. Recently however, boron neutron capture therapy (BNCT) with the use of p-borono-L-phenylalanine (BPA) for malignant melanoma has provided good results. CCS also produces melanin; therefore, the uptake of BPA is the key to the application of BNCT to CCS. We describe, for the first time, the high accumulation of boron in CCS and the CCS tumor-bearing animal model generated for BNCT studies.

Sacral radiculopathy secondary to multicentric osteosarcoma.

Study Design. A case of multicentric osteosarcoma presenting with sacral radiculopathy is reported. Objective. To present unusual clinical and radiologic findings of multicentric osteosarcoma. Summary of Background Data. Multicentric osteosarcoma is a rare variant of osteosarcoma. To the authors’ knowledge, no cases of multicentric osteosarcoma presenting as sacral radiculopathy have been reported previously. Methods. A 14-year-old boy had a large sacral tumor extending into the spinal canal, which was found to account for the initial symptoms, which mimicked those of herniated nucleus pulposus. At diagnosis, a bone survey showed multiple foci of osteosarcoma in the long bones. Results. The patient was treated with chemotherapy, but died of the disease 8 months after the initial presentation. Conclusion. Multicentric osteosarcoma should be considered in the differential diagnosis for a pediatric patient with low back pain and sciatica.

Boron neutron capture therapy (BNCT) selectively destroys human clear cell sarcoma in mouse model

Clear cell sarcoma of tendons and aponeuroses (CCS) is a rare malignant tumor with no effective treatment. This study demonstrates the efficacy of BNCT with the use of human CCS-bearing nude mice. Groups A and C were administered saline, and groups B and D were injected with p-borono-L-phenylalanine-fructose complex. Groups C and D were then irradiated with thermal neutrons. The tumors in only group D disappeared, demonstrating that BNCT is a potentially new option for the treatment of human CCS.