Magnetic resonance imaging findings of microgeodic disease of the toe: a case report

Level of Evidence: V, Expert Opinion

Factors Affecting Prosthetic Rehabilitation Outcomes in Amputees of Age 60 Years and Over

This retrospective, observational study was designed to investigate factors affecting successful prosthetic ambulation in elderly amputees aged ≥ 60 years. The study included 64 unilateral transfemoral or hip disarticulation amputees. Patients who were able to walk ≥ 100 m with prosthesis were classified as successful and those who could walk < 100 m as failures. Age, comorbidities, cause of amputation, ability to stand on one leg, patient's motivation for walking and maximum oxygen uptake as a proportion of predicted maximum oxygen uptake (%VO2max) during an exercise load test were examined as indicators of physical fitness. Significant differences were noted between the two groups in the number of comorbidities, ability to stand on one leg, patient's motivation for walking and mean %VO2max. A low number of comorbidities, the ability to stand on one leg, motivation for walking and adequate physical fitness allowing an exercise intensity of ≥ 50% VO2max were considered to be predictive factors for successful prosthetic rehabilitation.

Treatment of subungual glomus tumor

We report four cases of chronic obscure pain in the finger tips. High-resolution magnetic resonance imaging (HR-MRI) findings helped diagnose the existence of a mass at the subungual area and all patients were treated with excision and biopsy. The pathological diagnosis was glomus tumor. HR-MRI is useful in the diagnosis of patients with subungual glomus tumor.

Enhancement of tendon-bone osteointegration of anterior cruciate ligament graft using granulocyte colony-stimulating factor

BACKGROUND

Whereas anterior cruciate ligament rupture usually requires reconstruction, the attachment between the tendon and the bone is the weakest region in the early posttransplantation period. In this process, the acquisition of appropriate vascularity is a key for early bone-tendon healing.

HYPOTHESIS

Granulocyte colony-stimulating factor has an effect on the maturation of bone-tendon integration of anterior cruciate ligament reconstruction.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty-eight healthy adult beagle dogs underwent bilateral anterior cruciate ligament reconstruction using the ipsilateral flexor digitorum superficialis tendon and were divided into 2 groups. A granulocyte colony-stimulating factor-incorporated gelatin surrounded the graft in the granulocyte colony-stimulating factor group, and the same gelatin without granulocyte colony-stimulating factor was used as the control group. Assessment was done at 2 and 4 weeks.

RESULTS

Histological analysis at week 2 demonstrated that, in addition to more Sharpey fibers, microvessels were significantly enhanced in the granulocyte colony-stimulating factor group's grafts. Computed tomography at week 4 showed a significantly smaller tibial bone tunnel in the granulocyte colony-stimulating factor group. Real-time polymerase chain reaction revealed significantly elevated messenger ribonucleic acid expression levels of vascular endothelial growth factor and osteocalcin in the tibial bone tunnel and graft compared with controls. Furthermore, biomechanical testing of force during loading to ultimate failure at week 4 demonstrated a significant increase in strength in the granulocyte colony-stimulating factor group.

CONCLUSION

This study demonstrated that a local application of granulocyte colony-stimulating factor-incorporated gelatin significantly accelerates bone-tendon interface strength via enhanced angiogenesis and osteogenesis.

CLINICAL RELEVANCE

Granulocyte colony-stimulating factor has therapeutic potential in promoting an environment conductive to angiogenesis and osteogenesis in bone tunnels.

Inhibition of PKCalpha activation in human bone and soft tissue sarcoma cells by the selective PKC inhibitor PKC412

BACKGROUND

PKC412, formerly CGP41251, N-benzoylstaurosporine, was initially developed as a selective protein kinase C (PKC) inhibitor, and it preferentially inhibits conventional PKC family members. In this study, the expression of PKCa was examined in human osteosarcoma and MFH cell lines, and the inhibitory effect of PKC412 on the proliferation of the cell lines was evaluated.

MATERIALS AND METHODS

Three human osteosarcoma cell lines (KTHOS, MG63 and KHOS) and four human MFH cell lines (TNMY1, GBS-1, Nara-F and Nara-H) were used. The expression of PKCalpha and phosphorylated PKCalpha were analyzed using both Western blotting analysis and immunocytochemical analysis. The effect of PKC412 on cell proliferation was evaluated using the MTS assay technique.

RESULTS

PKC412 inhibited cell proliferation of all seven cell lines in a dose- and time-dependent manner. Both Western blotting analysis and immunocytochemical analysis revealed that not only PKCalpha but also phosphorylated PKCalpha were expressed in all cell lines incubated with the culture medium without any stimuli. PKC412 suppressed phosphorylation of PKCalpha in all cell lines at a concentration of 1 microM.

CONCLUSION

The inhibition of cell proliferation of the human osteosarcoma and MFH cell lines by PKC412 might be due to reduced PKCalpha activity. This suggests PKC412 might be a potent chemotherapeutic agent for human sarcomas.

Intraosseous ganglion of the phalanx

Intraosseous ganglions occurring in the hand are rare. Most reported cases involve the lunate or the scaphoid. This report presents a very extremely rare case of intraosseous ganglion arising in the middle phalanx of an index finger. Multi-modality imaging features using plane radiograph, CT, and MRI of this ganglion are presented for the first time.

High level of ezrin mRNA expression in an osteosarcoma biopsy sample with lung metastasis

Osteosarcoma (OS) remains a life-threatening malignancy and its molecular character is not fully understood. Ezrin is a cytoskeleton linker protein involved in regulating the growth and metastatic capacity of cancer cells. However, the correlation between ezrin mRNA expression and clinical severity has not yet been examined in OS biopsy samples. Furthermore, recent evidence has demonstrated that the level of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression is increased in human cancers of various origins, but this has not yet been examined in OS cells. To clarify the correlation between the clinical severity and the levels of ezrin and GAPDH mRNA expression, we quantified these mRNA levels in 4 pediatric OS biopsy samples using real-time quantitative polymerase chain reaction. Among these 4 samples, ezrin mRNA expression was approximately 5-fold higher in a case with lung metastasis compared with the other cases without metastasis, suggesting an association between the ezrin mRNA expression level and metastasis. On the other hand, the GAPDH mRNA expression level was not related to the clinical severity. This is the first report to demonstrate a high level of ezrin mRNA expression in an OS biopsy sample with lung metastasis.

Treatment of a full-thickness articular cartilage defect in the femoral condyle of an athlete with autologous bone-marrow stromal cells

OBJECTIVES

Human bone-marrow stromal cells are believed to be multipotent even in adults. This study assessed the effectiveness of autologous bone-marrow stromal cells, which were embedded within a collagen scaffold, to repair a full-thickness articular cartilage defect in the medial femoral condyle of an athlete.

PATIENT AND METHODS

A 31-year-old male judo player suffering from pain in the right knee was reviewed. A 20 x 30-mm full-thickness cartilage defect (International Cartilage Repair Society classification (ICRS) grade IV) was revealed in the weight-bearing area of the medial femoral condyle. With the informed consent of the patient, the defect was treated with autologous bone-marrow stromal cells. Bone marrow was aspirated from the iliac crest of the patient 4 weeks before surgery. After removing the erythrocytes, the remaining cells were expanded in culture. Adherent cells were collected and embedded within a collagen gel, which was transferred to the articular cartilage defect in the medial femoral condyle. The implant was covered with an autologous periosteal flap.

RESULTS

Seven months after surgery, arthroscopy revealed the defect to be covered with smooth tissues. Histologically, the defect was filled with a hyaline-like type of cartilage tissue which stained positively with Safranin-O. One year after surgery, the clinical symptoms had improved significantly. The patient had reattained his previous activity level and experienced neither pain nor other complications.

CONCLUSIONS

Our findings indicate that the transplantation of autologous bone-marrow stromal cells can promote the repair of large focal articular cartilage defects in young, active patients.

Imatinib mesylate inhibits tumorigenicity of malignant fibrous histiocytoma cells in vivo

BACKGROUND

Malignant fibrous histiocytoma (MFH) is one of the most diffuse and aggressive tumors among soft tissue sarcomas in adults, but still poorly characterized from the molecular viewpoint. MFH cell proliferation is inhibited selectively by imatinib mesylate, a tyrosine kinase inhibitor. The expressions of platelet-derived growth factor receptors (PDGFRs) and c-Kit have been previously examined in MFH cell lines and the inhibitory effect of imatinib mesylate on the MFH cell proliferation was tested. MFH cell lines showed various patterns of PDGFRs and c-Kit expression. Imatinib mesylate inhibited the proliferation of MFH cells that expressed PDGFRs and/or c-Kit.

MATERIALS AND METHODS

Four MFH cell lines were used (Nara H, Nara F, GBS-1 and TNMY1). The mRNA expression of PDGFRs and c-Kit was analyzed using RT-PCR; cell proliferation was analyzed using the MTS assay. Immunohistochemistry was used to analyze the inhibitory effect of imatinib mesylate on phosphorylation of PDGFRs and c-Kit in vivo. The Nara H and TNMY1 cell lines were implanted into nude mice and tumor growth was evaluated daily by measuring the two-dimensional diameters of the tumor nodule.

RESULTS

PDGFRs and c-Kit were expressed in Nara F, GBS-1 and TNMY1, but not in Nara H cells. Imatinib mesylate inhibited PDGFRs and c-Kit phosphorylation in TNMY1 cells affecting the tumorigenicity, in the control group (139 mm3 SD +/- 1.03) and treatment group (126.2 mm3 SD +/- 1.63) but did not affect the tumorigenicity of Nara H cells.

CONCLUSION

Imatinib mesylate reduced in vivo tumor growth of MFH that express PDGFRs and c-Kit associated with phosphorylation suppression.

Expression of VEGF and its receptors and angiogenesis in bone and soft tissue tumors

BACKGROUND

Tumor angiogenesis and vascularization are essential requirements for the growth and metastasis of tumors. There is evidence that overexpression of the vascular endothelial growth factor (VEGF) is correlated with an adverse prognosis in some tumors. The expression of VEGF, its receptors and microvessel density (MVD) of bone and soft tissue tumors was evaluated.

MATERIALS AND METHODS

Tissue specimens of 60 patients including 30 malignant and 30 benign tumors confirmed by biopsy were examined. Expression of VEGF and its receptors (flt-1 and KDR/flk-1) was observed by immunohistochemistry. Tumor angiogenesis was assessed morphologically by measuring intratumoral MVD.

RESULTS

Semi-quantitative evaluation of immunoreactivity showed that VEGF was significantly higher in malignant tumors than in benign tumors. A correlation was found between the immunoreactivity of VEGF and KDR. Moreover, correlations were found either between MVD and VEGF or between MVD and KDR/flk-1.

CONCLUSION

Signal transduction, in particular by VEGF and KDR, potentially contributes to the angiogenesis of bone and soft tissue tumor.

Three-dimensional images of contrast-enhanced MDCT for preoperative assessment of musculoskeletal masses: comparison with MRI and plain radiographs

PURPOSE

To evaluate the diagnostic capability of contrast-enhanced multidetector computed tomography (MDCT) for the preoperative assessment of musculoskeletal masses, in comparison with magnetic resonance imaging and plain radiographs (MRI+X-p).

MATERIALS AND METHODS

Sixty-eight patients with musculoskeletal masses underwent plain radiography, MRI, and contrast-enhanced MDCT. The following five items were evaluated for all images: histological properties, vascularity, neurovascular involvement, calcification/ossification, and cortical/marrow involvement. The MDCT images with three-dimensional reconstruction were retrospectively compared with MRI+X-p.

RESULTS

In 32 bone lesions, MDCT was superior/equal/inferior to MRI+X-p regarding histological properties in 4/10/18, vascularity in 0/11/21, neurovascular involvement in 0/26/6, calcification/ossification in 15/17/0, and cortical/marrow involvement in 29/3/0 cases, respectively. In 36 soft-tissue lesions, MDCT was superior/equal/inferior to MRI+X-p with histological properties in 1/18/17, vascularity in 0/12/24, neurovascular involvement in 1/24/11, calcification/ossification in 8/28/0, and cortical/marrow involvement in 7/29/0 cases, respectively. The MDCT evaluation of both calcification/ossification and cortical/marrow involvement in bone lesions was superior to that in soft-tissue lesions (p<0.05). There were no statistically significant differences between benign and malignant lesions in the evaluation of each of the five items.

CONCLUSION

MDCT provided additional and more comprehensive information than MRI+X-p for the preoperative assessment of musculoskeletal masses, especially for calcification/ossification and cortical/marrow involvement. Three-dimensional contrast-enhanced MDCT images can be adopted equally to MRI for the preoperative evaluation of neurovascular involvement.

Biceps tendinitis caused by an osteochondroma in the bicipital groove: a rare cause of shoulder pain in a baseball player

Tendinitis of the long head of the biceps brachii muscle is commonly seen in athletes who do repetitive overhead motions. Common causes of biceps tendinitis include impingement syndrome, subluxation of the biceps tendon, and attrition tendinitis, whereas biceps tendinitis secondary to a bone neoplasm is rare. A case of biceps tendinitis caused by an osteochondroma arising in the left humeral bicipital groove in a 25-year-old male baseball player is reported. The tumor was hook-shaped, originated from the inferomedial portion of the humeral lesser tubercle, and surrounded the biceps tendon. Symptoms of increasing pain and inability to throw resulted from direct irritation of the biceps tendon by the tumor. Total excision of the tumor relieved the symptoms within 3 weeks. To our knowledge, there have been no reported cases in the English-language literature of biceps tendinitis caused by an osteochondroma.

Establishment and characterization of a KIT-positive and stem cell factor-producing cell line, KTHOS, derived from human osteosarcoma

Osteosarcoma is a malignant bone tumor that commonly affects adolescents and young adults. In the present study a human osteosarcoma cell line, KTHOS, was established from a primary osteosarcoma lesion in the distal femur of a 16-year-old girl. After 106 passages, the KTHOS cell line retained the biological characteristics of osteosarcoma. The KTHOS cells had spindle to pleomorphic cytoplasm with round to ovoid nuclei containing multiple prominent nucleoli, as expected based on the mesodermic origin of osteoblasts. The KTHOS cells were immunoreactive for osteocalcin, osteonectin, stem cell factor (SCF), and KIT (CD117). Reverse transcriptase-polymerase chain reaction indicated that the KTHOS cell line expressed mRNA for SCF and KIT. The KTHOS cells produced relatively high amounts of soluble SCF as determined by enzyme-linked immunosorbent assay. The results suggest that cell proliferation of the KTHOS cell line might be involved in autocrine and/or paracrine loops of the SCF/KIT signaling system. The KTHOS cell line is a novel human osteosarcoma cell line that releases SCF and expresses KIT. This cell line can be used for studies to explore the mechanisms for oncogenesis of human osteosarcomas.

Apophysitis of the ischial tuberosity mimicking a neoplasm on magnetic resonance imaging

We present multimodality imaging features of an ischial tuberosity apophysitis in a 13-year-old boy who was an active baseball pitcher. Roentgenography of the pelvis and computed tomography showed mild irregularity in the inferior margin of the left ischial tuberosity. T1-weighted MRI showed a wide area with low signal intensity in the left ischial body; T2-weighted fat-suppression images showed areas with markedly high signal intensity in the ischial apophysis and body and the surrounding periosteum; contrast-enhanced T1-weighted fat-suppression MRI showed that the ischial body, surrounding periosteum, and origin of the hamstring muscles strongly enhanced; technetium-99m scintigraphic scans showed increased isotope uptake in the entire ischial body. Histological specimens obtained from the bone showed increased osteoblastic activity, edema, and proliferation of benign spindle cells and small vessels in the bone marrow spaces. In the present case, because MR imaging demonstrated extensive signal abnormalities involving the apophysis, periosteum, and intramedullary portion of bone, a neoplasm could not be excluded, and a biopsy was undertaken.

Effect of cyclic mechanical stretch and titanium particles on prostaglandin E2 production by human macrophages in vitro

Early implant instability has been proposed as a critical factor in the onset and progression of aseptic loosening and periprosthetic osteolysis in total joint arthroplasties. Previous in vitro studies have reported that macrophages stimulated with cyclic mechanical strain release inflammatory mediators. Little is known, however, about the response of these cells to mechanical strain with particles, which is often a component of the physical environment of the cell. We therefore studied the production of prostaglandin E(2) (PGE(2)), an important mediator in aseptic loosening and periprosthetic osteolysis in total joint arthroplasties, for human macrophages treated with mechanical stretch alone, titanium particles alone, and mechanical stretch and particles combined. A combination of mechanical stretch and titanium particles resulted in a statistically synergistic elevation of levels of PGE(2) compared with the levels found with either stretch or particles alone. Exposure of human macrophages to mechanical stretch with particles upregulated the expression of cyclooxygenase (COX)-2 mRNA but not COX-1 mRNA, this expression resulting in a 97-fold increase in PGE(2) production compared to the nonstimulated cells. The current study is the first to investigate the effects of mechanical stretch with particles on cultured macrophages and include an investigation of the time course of PGE(2) production and COX-2 mRNA expression. Our results suggest that, while mechanical strain may be one of the primary factors responsible for macrophage activation and periprosthetic osteolysis, mechanical strain with particles load may contribute significantly to the osteolytic potential of macrophages in vitro. The synergistic effect observed between mechanical stretch and particles could accelerate implant loosening and implies that reduction in either cyclic mechanical strain or wear debris load would lead to a reduction of osteolysis.

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

PURPOSE

Transforming growth factor beta (TGF-beta) is a multifunctional growth factor that variably affects proliferation, differentiation, and extracellular matrix formation. Little information is currently available on the TGF-beta expression in malignant fibrous histiocytoma (MFH). The aims of the present study were to investigate the expression of TGF-beta isoforms and their receptors in human MFH specimens.

EXPERIMENTAL DESIGN

The expression of TGF isoforms, and TGF-beta receptors (TGF-beta R1 and -beta R2) were immunohistochemically evaluated in 43 paraffin-embedded MFH specimens. Furthermore, the correlation of the TGF-beta and receptor expression with tumor proliferative activity assessed by MIB-1 indices was analyzed.

RESULTS

Positive immunoreactivity for TGF-beta1, -beta2, and -beta 3 was identified in tumor cells of 42, 40, and 38 of the 43 MFHs, respectively. In each TGF-beta 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-beta R1 and -beta R2 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-beta R1- and -beta R2-positive immunoreactivity (n = 23), and those with both or either TGF-beta R1- and -beta R2-negative immunoreactivity (n = 20). The MIB-1 indices in the both-TGF-beta R1- and -beta R2-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-beta ligand/receptor system with a significantly higher MIB-1 index in human MFHs. Investigation of the TGF-beta R1 and -beta R2 coexpression might be useful in predicting tumor behavior of MFHs.

Inhibitory effect of STI571 on cell proliferation of human malignant fibrous histiocytoma cell lines

BACKGROUND

Malignant fibrous histiocytoma (MFH) is one of the most common high-grade sarcomas in bone and soft tissue and, due to its chemo-resistance, the prognosis of the disease is poor. ST1571 is a tyrosine kinase inhibitor that was initially developed as a BCR/ABL inhibitor for chronic myeloid leukemia patients. STI571 also selectively inhibits platelet-derived growth factor receptors (PDGFRs) and c-kit. We examined the expression of PDGFRs and c-kit in human MFH cell lines, and the effect of STI571 on cell proliferation.

MATERIALS AND METHODS

Four human MFH cell lines (TNMY1, GBS-1, Nara-F and Nara-H) were used. mRNA expression of the receptor tyrosine kinases (PDGFRs and c-kit) was analyzed using reverse transcription-polymerase chain reaction, and the inhibitory effect of STI571 on cell proliferation was analyzed using the MTS assay technique.

RESULTS

PDGFRalpha mRNA was expressed in TNMY1 and GBS-1, and PDGFRbeta and c-kit mRNAs were expressed in TNMY1, GBS-1 and Nara-F. All three of these mRNAs were absent in Nara-H. STI571 inhibited cell proliferation of TNMY1, GBS-1 and Nara-F in a dose- and time-dependent manner, but cell proliferation of Nara-H was not inhibited by ST1571 at concentrations of 10 microM or less.

CONCLUSION

STI571 significantly inhibited proliferation of the three human MFH cell lines that expressed mRNAs of target receptor tyrosine kinases. The inhibitory effect of ST1571 on cell proliferation in these three cell lines might be due to decreased tyrosine kinase activity. STI571 might be a potent chemotherapeutic agent for human MFHs.

Phalangeal microgeodic syndrome resulting in rapid digital shortening

Microgeodic phalangeal syndrome is a rare condition affecting the fingers in children. Radiographically, the affected phalanges show sclerosis with multiple small areas of osteolysis. The pathogenesis of microgeodic phalangeal syndrome is considered to be a transient disturbance of the peripheral circulation caused by cold temperatures. In most cases, the symptoms and the radiographic changes return to normal within several months without any treatment. We present a rare case of microgeodic phalangeal syndrome in the middle phalanx of the right index finger in an 8-year-old girl, in whom the affected phalanx shortened within 6 weeks of the initial presentation. It was speculated that minor trauma to the finger might have contributed to the collapse and shortening of the phalanx. The current case indicates that the use of a splint for the affected finger in the early period after onset of symptoms might be recommended to avoid digital shortening.

Coexpression of hepatocyte growth factor and its receptor c-Met correlates with high MIB-1 proliferative index in malignant fibrous histiocytoma

Hepatocyte growth factor (HGF) is a multifunctional cytokine that variably affects cell motility, proliferation, and morphogenesis. Little information is currently available on the HGF and its receptor c-Met expression in malignant fibrous histiocytoma (MFH). We immunohistochemically investigated the HGF and c-Met expression in 43 MFH tissue specimens. Furthermore, the correlation of the HGF and c-Met expression with tumor proliferative activity assessed by MIB-1 indices was analyzed. Our results showed that positive cytoplasmic immunoreactivity for HGF and c-Met was identified in tumor cells in 36 (84%) and 20 (47%) of the 43 MFH cases analyzed, respectively. Coexpression of HGF and c-Met was observed in 20 (47%) of the 43 MFHs, and was correlated with high MIB-1 proliferative indices (p = 0.0446). These findings strongly indicate that the HGF/c-Met signaling system plays an important role in promoting cell proliferation of human MFHs via an autocrine loop.

Expression of betacellulin, heparin-binding epidermal growth factor and epiregulin in human malignant fibrous histiocytoma

BACKGROUND

Heparin-binding epidermal growth factor (HB-EGF), betacellulin (BTC) and epiregulin (EPR) are members of the EGF system and involved in the cell growth of various epithelial malignancies. There have been no reports on the HB-EGF, BTC and EPR expression in mesenchymal malignancies of fibrohistiocytic origin including malignant fibrous histiocytoma (MFH).

MATERIALS AND METHODS

We investigated the expression of HB-EGF, BTC, EPR and EGF-receptor (EGF-R) in 43 human MFH tissue samples using immunohistochemical techniques.

RESULTS

Positive immuno-reactivity for HB-EGF, BTC, EPR and EGF-R was identified in 28 (65%), 7 (16%), 43 (100%) and 36 (84%) out of the 43 MFH cases analyzed, respectively. Coexpression of HB-EGF/BTC, BTC/EPR and HB-EGF/EPR was observed in 6 (14%), 7 (16%) and 28 (65%) of the MFHs, respectively. Coexpression of HB-EGF/EGF-R, BTC/EGF-R and EPR/EGF-R was observed in 25 (58%), 6 (14%) and 36 (84%) of the MFHs, respectively.

CONCLUSION

These results revealed that HB-EGF, BTC and EPR are expressed not only by epithelial tumor cells, but also by MFH cells. It is suggested that HB-EGF and EPR might be more important tumor growth regulators of MFH through autocrine or paracrine pathways, when compared with BTC.

Tarsal tunnel syndrome caused by epineural ganglion of the posterior tibial nerve: report of 2 cases and review of the literature

Ganglia within the posterior tibial nerve is a rare condition. The authors report 2 cases of epineural ganglion of the posterior tibial nerve, causing tarsal tunnel syndrome. Both cases presented with numbness on the plantar surface of the foot. Magnetic resonance imaging showed the presence of the cyst within the tarsal tunnel. During surgery, these cysts were found within the epineurium of the posterior tibial nerve and were successfully removed without damage to nerve fibers. Both patients were free of symptoms after surgery. Ganglion cysts in the peripheral nerve are either intrafascicular or epineural. Intrafascicular ganglia present beneath the epineurium and involve the nerve fibers, whereas epineural ganglia are located in the epineurium and do not involve the nerve fibers. A review of the literature discusses these concepts. The authors suggest that epineural ganglion should be clinically distinctive from an intrafascicular ganglion because of the differences in surgical treatment, postoperative nerve function, and the recurrence rate.

Amphiregulin and epidermal growth factor receptor expression in human malignant fibrous histiocytoma of soft tissues

BACKGROUND

Amphiregulin is a member of the epidermal growth factor (EGF) system and a potent mitogen for various epithelial tissues. Little information, however, is currently available on the amphiregulin and EGF receptor (EGF-R) expression in mesenchymal malignancies of a fibrohistiocytic origin including malignant fibrous histiocytoma (MFH).

MATERIALS AND METHODS

We investigated the amphiregulin and EGF-R expression in 43 human MFH tissues using immunohistochemical techniques. Furthermore, the correlation of the ligand and the receptor expression with tumor proliferative activity assessed by MIB-1 indices was analyzed.

RESULTS

Positive immunoreactivity for amphiregulin and EGF-R was identified in 34 (79%) and 36 (84%) of the 43 MFH cases analyzed, respectively. Coexpression of amphiregulin and EGF-R was observed in 30 (70%) of the 43 MFHs analyzed. There were no significant differences in MIB-1 indices between both the amphiregulin and EGF-R-positive MFHs and the remaining MFHs.

CONCLUSION

These results show that amphiregulin is expressed not only by epithelial tumor cells but also by MFH cells. Our data provide evidence indicating the presence of an autocrine mechanism of proliferation control involving the amphiregulin/EGF-R signaling system in human MFHs.

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.

Neurilemmoma in the foot as a cause of heel pain: a report of two cases

Two cases of deep-seated neurilemmoma that arose from plantar branches of the posterior tibial nerve and caused chronic heel pain are described. At the initial examination, one case was misdiagnosed as tarsal tunnel syndrome and the other was overlooked as plantar fasciitis; both cases were treated for long periods prior to operation. Deep-seated neurilemmomas in the foot can easily be overlooked and misdiagnosed as tarsal tunnel syndrome or plantar fasciitis because of the rarity, absence of palpable mass, and similarity of symptoms to those of other frequently encountered foot disorders. Magnetic resonance imaging provides the best modality for differential diagnosis. In the present cases, surgical excision of the tumors resulted in immediate and complete relief of chronic heel pain. Surgeons should consider neurilemmoma as a cause of persistent chronic heel pain despite the rarity of the disease.

Extraabdominal desmoid tumor in a surgical scar of a patient with Sprengel's deformity

Patients with an extraabdominal desmoid tumor have multiple minor bone abnormalities. The authors describe a rare case of an extraabdominal desmoid tumor that developed in a scar 2 years after surgery for Sprengel's deformity of the right shoulder in an 8-year-old girl. The association between the tumor and Sprengel's deformity has never been reported previously. Antecedent surgical trauma might play a role in the development of this tumor.

"Backside" polyethylene deformation in total knee arthroplasty

The clinical importance of polyethylene deformation between the tibial insert and base plate ("backside") is unclear. We used a semiquantitative scoring system to compare clinical and radiographic factors with articular and backside deformation of 106 retrieved polyethylene tibial inserts. Backside deformation was associated with polyethylene thickness and type of locking mechanism. Deformation of the articular surface correlated with femoral osteolysis (P=.05). The mean backside deformation score was 33% greater for implants from patients with osteolysis than for implants from patients without osteolysis (P=.07). Our study may be biased based on the types of implants available for study, but for this group of implants, we cannot conclude with 95% certainty that backside polyethylene deformation was clinically important as a cause of periprosthetic osteolysis or implant loosening.

Expression of stem cell factor and lack of c-kit expression in malignant fibrous histiocytoma of soft tissues

BACKGROUND

Little information is available on the expression of stem cell factor (SCF) and its receptor c-kit in soft tissue tumors of a fibrohistiocytic origin, including malignant fibrous histiocytoma (MFH).

MATERIALS AND METHODS

We investigated the endogenous expression of SCF and c-kit in 43 MFH tissue samples using immunohistochemical techniques. Furthermore, we examined the correlation of SCF expression in MFHs with proliferative activity assessed by mitotic indices and MIB-1 immunohistochemical staining.

RESULTS

Positive immunoreactivity for c-kit was identified in tumor cells of only one MFH case, while the remaining 42 cases were negative. In the one positive case, immunohistochemical staining was focal. Positive immunoreactivity for SCF was identified in 31 out of 43 cases studied (72%, focal; 11, moderate; 6, diffuse; 14). There were no significant differences in the MIB-1 and mitotic indices between the SCF-positive and negative groups.

CONCLUSION

Our data indicate that any direct autocrine effects of the SCF/c-kit system on cell growth regulation are precluded in most MFH cases studied, but it is speculated that SCF might indirectly influence tumor growth by promoting local neovascularization.

Immunohistochemical analysis of platelet-derived growth factor and its receptors in soft tissue malignant fibrous histiocytoma

BACKGROUND

Little information is available regarding the expression of platelet-derived growth factor (PDGF) isoforms and their receptors in soft tissue malignant fibrous histiocytoma (MFH).

MATERIALS AND METHODS

We investigated expression of PDGF isoforms and their receptors (PDGF-R alpha and -R beta) in 43 MFH tissue specimens using immunohistochemical techniques. Furthermore, we examined the correlation of PDGF expression in MFHs with proliferative activity assessed by MIB-1 immunohistochemical staining.

RESULTS

Positive cytoplasmic immunoreactivity for PDGF-AA, -BB and -AB was identified in tumor cells of 28 (66%), 4 (10%) and 26 (61%), respectively, of the 43 MFHs analyzed. Positive cytoplasmic immunoreactivity for PDGF-R alpha and -R beta was identified in tumor cells of 41 (95%) and 32 (74%), respectively, of the MFHs. Thirty-four (79%) MFHs coexpressed one or more PDGF isoforms and their corresponding receptors. In PDGF-AA immunostaining, MIB-indices in the high immunoreactivity group (> 10% of tumor cells) were significantly higher than those in the low immunoreactivity group (< 10% of tumor cells) (p = 0.031).

CONCLUSION

Our data provide evidence to support the presence of an autocrine/paracrine mechanism of proliferation control involving the PDGF ligand/receptor system in human MFHs.

Multimodality imaging features of primary xanthoma of the calcaneus

Secondary xanthomatous features are histologically observed in various bone lesions, but primary xanthoma of bone is rare. We present a primary xanthoma of the right calcaneus in a 51-year-old woman who had no aberrant lipid metabolism. Roentgenograms showed a small osteolytic lesion in the calcaneal triangle, partially surrounded by bone sclerosis. Computed tomographic scans of the calcaneus showed multiple osteolytic areas, with an irregular trabecular pattern in the surrounding sclerotic bone. T1-weighted magnetic resonance images showed a lesion with central low signal intensity, surrounded by a peripheral ring with high signal intensity. The entire lesion showed high signal intensity on T2-weighted images, partially surrounded by areas with low signal intensity, concordant with reactive bone sclerosis. Histologically, the lesion consisted of numerous lipid-laden histiocytes arranged in sheets, scattered multinucleated giant cells and lymphocytes, and granulation tissues. There was no evidence of pre-existing lesions. Total excision of the tumor was curative.

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.

Expression of stem cell factor and c-kit in human malignant fibrous histiocytoma cell line (TNMY1)

BACKGROUND

The expression of c-kit and/or its ligand, stem cell factor (SCF), has been related to tumor proliferation, in several tumor systems.

MATERIALS AND METHODS

We analyzed the expression of the SCF/its receptor (c-kit) mRNA and the production of soluble SCF in a human malignant fibrous histiocytoma (MFH) cell line (TNMY1).

RESULTS

Immunocytochemical analysis revealed that the TNMY1 cells were positive for both SCF and c-kit. Reverse transcriptase-polymerase chain reaction (RT-PCR) showed that the TNMY1 cell line expressed mRNA for SCF and c-kit. By using an enzyme-linked immunosorbent assay (ELISA), the TNMY1 cells were found to produce relatively high amounts of soluble SCF. However, the addition of soluble SCF to the TNMY1 cells did not alter the in vitro growth ability of the cells.

CONCLUSION

Our data showed that the MFH cells produced consistent amounts of SCF but did not demonstrate autocrine growth modulation. Thus, SCF secretion may have a paracrine activity in the growth of MFH cells.

Bone marrow edema syndrome associated with uterine myoma: a case report

A patient with bone marrow edema syndrome of the hip associated with a uterine myoma is presented. A 51-year-old woman could not walk because of severe pain in both hips and had been referred to the authors' institute. Magnetic resonance imaging scans showed abnormal intensity on T1- and T2-weighted images in both femoral heads and a large mass arising from the uterus which was diagnosed as a uterine myoma. A 99mTc-methylene diphosphonate scintigraph showed diffuse uptake in both femoral heads. The pain in both hips decreased shortly after a hysterectomy and the patient could walk without crutches within 2 weeks after the gynecologic surgery. Magnetic resonance imaging scans taken 8 months after surgery showed high signal intensity on T1- and T2-weighted images, indicating normal bone marrow in the femoral heads. To the authors' knowledge, this is the first case report showing a bone marrow edema syndrome of the hip associated with uterine myoma. The pathophysiologic mechanisms for bone marrow edema syndrome of the hip in the current patient and in pregnancy may be identical. More specifically, a large intrapelvic mass may cause an increase of intrapelvic pressure and subsequent blood stasis in both conditions. The current case suggests the possible factors of bone marrow edema syndrome of the hip which need to be investigated.

Granulocyte colony-stimulating factor-producing undifferentiated sarcoma occurring in previously fractured femur. A case report and review of the literature

We examined the case of a 52-year-old man presenting with a sarcoma accompanied by severe leukocytosis, which developed many years after a femoral fracture. Histologic, histochemical, immunohistochemical, and ultrastructural analysis of the tumor revealed that the sarcoma could not be classified by any of the bone or soft tissue tumor classifications currently in use. The tumor cells were isolated from surgical specimens and subcultured in vitro. The concentration of granulocyte colony-stimulating factor in the culture medium was constantly elevated to considerably high levels during 20 cell passages. A genomic study using reverse transcription-polymerase chain reaction showed that the cells retained messenger RNA expression of granulocyte colony-stimulating factor. The aberrant overexpression of granulocyte colony-stimulating factor clearly represented a paraneoplastic phenomenon of the neoplastic cells.

Fine-needle aspiration biopsy of solid aneurysmal bone cyst in the humerus

We report the fine-needle aspiration biopsy (FNAB) cytology findings of a solid aneurysmal bone cyst in the left humerus of a 69-yr-old woman. Radiographically, the lesion showed an extensive, relatively well-defined osteolysis in the diaphysis, with a pathologic fracture. FNAB smears of the lesion consisted of benign, mononuclear cells and numerous osteoclast-like multinucleated giant cells. Some clusters of the mononuclear cells were closely associated with dense, homogeneous, extracellular, matrix material. To our knowledge, the FNAB features of solid ABC of the long bones have not been described previously in the English-language literature. The cytologic features are indistinguishable from those of giant cell tumors of bone and brown tumors of hyperparathyroidism.

Isolated suprapatellar bursitis: Computed tomographic and arthroscopic findings

A rare case of compartmentalized suprapatellar bursitis in the left knee of an 80-year-old man is presented. Computed tomographic (CT) scans following intravenous administration of contrast media showed a cystic mass between the quadriceps tendon and the anterior surface of the femur. Multiplanar reconstruction CT scans showed a mass superior to the patella, the wall of which was enhanced. Arthroscopic examination of the knee revealed a complete suprapatellar septum that separated the suprapatellar bursa from the knee joint cavity. Surgical excision of the bursa was curative. To our knowledge, multiplanar reconstruction CT and arthroscopic features of the isolated suprapatellar bursitis have not been illustrated previously.

Management of liposarcoma occurring in pregnant women

BACKGROUND

The coexistence of pregnancy and liposarcoma is rare. Only 12 cases of pregnancy-associated liposarcoma have previously been reported in the English-language literature.

MATERIALS AND METHODS

We present two cases of liposarcoma occurring in pregnant patients: one myxoid liposarcoma in a 29-year-old woman at 29 weeks' gestation; another well-differentiated liposarcoma in a 44-year-old woman at 22 weeks' gestation.

RESULTS

The first patient's infant was delivered by cesarean section after the confirmation of pulmonary maturity of the fetus. The patient was subsequently treated with chemotherapy and radiotherapy. The second patient awaited delivery until 32 weeks' gestation with no treatment of the tumor because she had a low-grade sarcoma. After cesarean section, surgical treatment followed.

CONCLUSION

Treatment of sarcomas occurring during pregnancy is difficult. Both mother and fetus should be appropriately managed, depending on the trimester at the time of diagnosis and the histological type and grade of the tumor.

Fine-needle aspiration biopsy in the initial diagnosis of bone lesions

BACKGROUND

The diagnostic role of fine-needle aspiration biopsy (FNAB) of bone lesions is not yet fully understood. The aim of this study was to examine the diagnostic accuracy and reliability of FNAB of bone lesions.

MATERIALS AND METHODS

FNAB smears of 73 lesions obtained from 70 patients with bone lesions were retrospectively reviewed randomly, combined with clinical and radiological findings.

RESULTS

Of the 73 FNAB cases analyzed, 67 (92%) were considered to be adequate for diagnosis. The sensitivity and specificity were 100% and 86%, respectively. The positive and negative predictive values were 94% and 100%, respectively. The specific FNAB diagnoses were correct in 63% of the benign group, 89% of the malignant group and 17% of the nonneoplastic group.

CONCLUSION

FNAB of bone is a simple, safe, rapid, reliable and cost-effective diagnostic procedure. FNAB is suggested to be helpful in the workup and management of patients with bone lesions.

Ischiogluteal bursitis: multimodality imaging findings

Ischiogluteal bursitis is a rare, infrequently recognized condition. Two cases of ischiogluteal bursitis in an 80-year-old man and a 75-year-old woman are presented. Both patients presented with a painful buttock mass. Contrast-enhanced multiplanar reconstruction computed tomography scans revealed a lesion with peripheral enhancement inferior to the ischial tuberosity. Magnetic resonance imaging revealed a lesion with low or intermediate signal intensity on T1-weighted images. T2-weighted images revealed a lesion with high signal intensity. Postcontrast magnetic resonance imaging scans revealed peripheral enhancement of the lesion. The multimodality imaging findings of ischiogluteal bursitis have not been described previously. Ischiogluteal bursitis should be considered in the differential diagnosis of a buttock mass.

Reliability of fine-needle aspiration biopsy in the initial diagnosis of soft-tissue lesions

We retrospectively reviewed fine-needle aspiration biopsy (FNAB) specimens of 301 soft tissue lesions of the extremities and trunk. Final diagnoses were 137 benign and 86 malignant neoplasms and 78 nonneoplastic lesions. Of the 301 FNAB samples, 279 (93%) were adequate for cytologic diagnosis. The adequate FNAB specimens were initially grouped into three broad categories: benign (197 cases), malignant (57 cases), and suspicious for malignancy (25 cases). Sensitivity and specificity for diagnosis of a malignant lesion were 92% and 97%, respectively. The specimens were cytomorphologically classified into nine categories: small round (14 cases), spindle cell (77 cases), epithelioid/polygonal (16 cases), pleomorphic (29 cases), myxoid (19 cases), lipomatous (37 cases), epithelial (23 cases), inflammatory lesions (28 cases), and others (36 cases). Specific FNAB diagnoses were correct in 151 of 279 cases (54%) in combination with clinical and radiologic findings. FNAB is a valuable technique for the primary diagnosis of soft-tissue lesions.

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 x 3 x 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.

Reimplantation of autoclaved or irradiated cortical bones invaded by soft tissue sarcomas

BACKGROUND

Bone defects after excision of malignant bone and soft tissue tumors are usually reconstructed by autogenous bone grafting or allografting.

PATIENTS AND METHODS

We treated 2 patients who had soft tissue sarcomas with bone involvement, the first by excision and reimplantation of the hemicortical autogenous cortical bone graft after autoclaving and the second with intraoperative irradiation.

RESULTS

In both patients, postoperative follow-up radiographic studies showed incorporation of the implanted bones into the host bones within 12 months. Biopsy of the implanted bone performed 3 years after surgery showed many viable osteocytes, and blood vessel invasion into Harversian canals. No complications regarding the reconstructive techniques were observed during the postoperative period.

CONCLUSION

The reimplantation of autogenous cortical bones after autoclaving or irradiation is a useful reconstructive method for partial bone defects in soft tissue tumor surgery.

Scrape and fine-needle aspiration cytology of elastofibroma

BACKGROUND

Cytological findings of elastofibroma have rarely been reported and, to the best of our knowledge, have been illustrated in only 4 patients in the English language literature.

MATERIALS AND METHODS

We retrospectively reviewed fine-needle aspiration biopsy (FNAB) and scrape smears in 5 cases of elastofibroma.

RESULTS

All the lesions were typically located between the rib cage and the scapula. The cytological smears consisted of mature adipocytes, fibroblasts, collagen fibers, globular bodies and characteristic "braid-like" or "fern-like" structures, revealing degenerative elastic fibers. All the smears were specifically diagnosed as elastofibroma in combination with clinical and radiological findings.

CONCLUSION

FNAB smears of elastofibromas may be hypocellular due to their densely fibrous nature and therefore diagnostic material may often be overlooked. Careful evaluation of the background of the smears coupled with full knowledge of the clinical and radiological findings, including magnetic resonance imaging, is required to establish the correct diagnosis.

Scrape and fine-needle aspiration cytology of extraskeletal osteosarcoma

Extraskeletal osteosarcoma is a rare malignant soft tissue tumor whose cytologic findings are infrequently reported. We describe scrape and fine-needle aspiration biopsy (FNAB) cytology findings of an extraskeletal osteosarcoma in the right shoulder of a 24-yr-old man. Initial computed tomography revealed multiple ossification foci within the lesion. After excision of the primary tumor, the tumor recurred 13 months later. Scrape smears of both the primary tumor and FNAB smears of the recurrent tumor revealed moderate cellularity, cell clusters, and individual cells, closely associated with dense, homogeneous, acellular matrix material. The cells had elongated, oval, or partially bizarre-shaped nuclei with a coarse chromatin pattern and prominent nucleoli. The scrape smears contained large fragments of matrix material consistent with osteoid.

Subacute osteomyelitis of long bones: diagnostic usefulness of the "penumbra sign" on MRI

Although subacute osteomyelitis of long bones is not uncommon, it is usually confined to metaphysis. Two unusual cases of subacute osteomyelitis that traversed a growth plate are described. There may be some radiological difficulties in distinguishing it from other malignant or benign lesions. On magnetic resonance (MR) imaging, both of the present cases showed characteristic four-layered appearance and the penumbra sign. These characteristic findings on MR imaging are considered to facilitate establishing the radiologic diagnosis.