Faculty Bibliography

We report a case of a 38-year-old man with a well-differentiated extraosseous chondrosarcoma of the foot. This case is unusual because the tumor originated in the soft tissues of the foot and developed pulmonary metastases. It is also interesting to note that at the time of recurrence 8 years later, the lesion invaded the third metatarsophalangeal joint and adjacent bones. Well-differentiated chondrosarcoma resembling hyaline cartilage, primary in soft tissue, is a rare histological type, and only a few cases have been reported in the foot. The patient is alive and well 4.5 years after resection of the foot tumor and partial resection of the lung metastases

PURPOSE: The purpose of this study was to review our experience with a benign surface bone lesion referred to as bizarre parosteal osteochondromatous proliferation (BPOP) or Nora's lesion, named for the pathologist who described it in 1983. The lesion may be confused with a variety of tumors, particularly solitary osteochondromas, which are rare. METHODS: The files in the Department of Pathology at the Hospital for Joint Diseases were reviewed over a 21-year period for all surface bone lesions involving the tubular bones in the hand. There were a total of 10 cases of BPOP compared with only a single case of an osteochondroma. RESULTS: Radiographs generally showed a well-marginated uniformly dense mass arising from the surface of the affected bone without any disruption in its bony architecture. Surgical excision is the definitive treatment and included the fibrous pseudocapsule over the lesion, any periosteal tissue beneath the lesion, and any area of the cortex of the host bone that appeared abnormal. Although in the medical literature the recurrence rate for BPOP is high, we had only one recurrence in our series. CONCLUSIONS: BPOP is a benign surface bone lesion that may be confused with benign and malignant tumors. Although there is a cleavage plane between the lesion and host bone, we recommend excising the pseudocapsule over the lesion, any periosteal tissue beneath the lesion, and decorticating any abnormal-appearing areas in the underlying host bone. This may explain the low recurrence rate in our series

This study performed the first in vitro histological analysis of the effects of bipolar thermal energy on human meniscal tissue. Sixteen fresh human menisci were mounted on a cutting block and placed in a water bath simulating an arthroscopic environment. Each specimen was divided into four sections and randomized to one of four treatment options: 1. thermal ablation with a bipolar multielectrode 3 mm Covac wand (power 3 setting); 2. thermal ablation with a bipolar multielectrode 3 mm Covac wand (power setting 7); 3. resection with a scalpel blade; and 4. resection with a motorized 4.5 full-radius resector. Six micron sections were cut and stained with Hematoxylin and Eosin and Masson's trichrome stain. Menisci were evaluated for the contour of the cut edge: straight, jagged, frayed, or combined. The zone of thermal necrosis and zone of thermal alteration were determined by examining the differential staining of the connective tissue and measuring the affected area. Menisci treated with the bipolar thermal probe were noted to have a smoother contoured edge in comparison to motorized cutters. The zone of thermal penetration for the Arthrocare power setting 3 averaged 0.18 mm (range: 0.09 to 0.20; SD 0.04) and for Arthrocare power setting 7 averaged 0.33 mm (range: 0.26 to 0.36; SD 0.03). The difference in thermal penetration between Arthrocare power settings 3 and 7 was 0.15 mm. This was statistically significant at p < 0.0001 (95% CI: 0.11 to 0.19 mm). The zone of thermal penetration was non-existent for the shaver and scalpel groups. This study provides the first histological description of the effects of bipolar radiofrequency energy on meniscal tissue. It demonstrates that there is intra-substance thermal penetration and alteration of the meniscal tissue. Its clinical significance is unclear and further in vivo studies are needed to address its clinical applicability

A broad spectrum of tumorlike lesions and neoplasms can occur in the hand and wrist, although with somewhat less frequency than in other parts of the body. A thorough understanding of the differential diagnosis of these lesions and a comprehensive strategy for evaluation are central for effective care. Plain radiographs are diagnostic for most bony lesions, whereas magnetic resonance imaging may be necessary to help differentiate a benign soft-tissue lesion from the rare malignant neoplasm. In spite of the complex anatomy, adherence to proper oncologic principles most often will lead to a satisfactory outcome

We report a case of a 14-year-old boy with an intracompartmental lytic lesion with poorly defined margins in the right distal tibia that was originally treated with curettage and bone grafting. Histologic examination showed an osteoblastic tumor with unusual features, which was found on consultation to be an osteoblastoma-like osteosarcoma, a rare, low-grade variant of osteosarcoma. Subsequently, the patient underwent en bloc resection of the distal tibia, which was replaced with vascularized bone graft and followed by chemotherapy. Two years later, he is alive with lung metastases

We describe two cases of pigmented villonodular synovitis affecting true bursae. This study was also designed to discuss the term 'pigmented villonodular bursitis', not confined to true synovial bursae, sometimes creating misunderstanding

OBJECTIVE: To identify extracellular and intraarticular matrix components that are differentially expressed in normal and osteoarthritis (OA)-affected cartilage and to investigate their functions with respect to regulation of mediators of inflammation. METHODS: Differential-display reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of a pool of messenger RNA (mRNA) from 10 human OA cartilage samples and 5 normal cartilage samples was performed using arbitrary primers. Confirmatory analysis of the up-regulated transcripts of fibronectin (FN) and osteopontin (OPN) was performed by RT-PCR of individual RNA samples from a separate set of donors. The effect of recombinant OPN (or anti-OPN antiserum) on chondrocyte function was examined by analyzing the spontaneous or interleukin-1 (IL-1)-induced release of nitric oxide (NO) and prostaglandin E2 (PGE2) from human OA-affected cartilage under ex vivo conditions. RESULTS: Up-regulation (300-700%) of FN and OPN mRNA was observed in human OA-affected cartilage as compared with normal cartilage. Functional analysis of the role of OPN in OA cartilage showed that 1) Addition of 1 microg/ml (20 nM) of recombinant OPN to human OA-affected cartilage under ex vivo conditions inhibited spontaneous and IL-1beta-induced NO and PGE2 production, and 2) neutralization of intraarticular OPN with anti-OPN antiserum augmented NO production. CONCLUSION: The data indicate that one of the functions of intraarticular OPN, which is overexpressed in OA cartilage, is to act as an innate inhibitor of IL-1, NO, and PGE2 production. These findings suggest that the production of pleiotropic mediators of inflammation that influence cartilage homeostasis, such as NO and PGE2, is regulated by the interaction of chondrocytes with differentially expressed proteins within the extracellular matrix

The tyrosine kinase receptor c-kit and its ligand [kit ligand (KL) or stem cell factor (SCF)] exert a broad range of biological activities during organogenesis and normal cell development. Recent studies have revealed that altered c-kit levels occur in a variety of malignancies and cancer cell lines. KL has also been shown to stimulate the growth of malignant cells, as well as to promote chemotaxis. We had previously reported expression of KL in stroma cells of normal human prostate. The present study was undertaken in order to analyze the patterns of expression of c-kit and KL in a well characterized set of prostatic tissues, including normal prostate (n=4), benign prostatic hyperplasia (BPH) (n=53) and adenocarcinoma (n=46) samples. The distribution of c-kit and KL proteins was studied by immunohistochemical analyses, while transcript levels were determined by in situ hybridization with specific RNA probes on a subset of the benign and malignant tissues referred above. In addition, reverse-transcriptase polymerase chain reaction (RT-PCR) was performed to determine levels of c-kit and KL expression in cultures of epithelial and stroma cells, as well as in the prostate cancer cell lines LNCaP, DU145 and PC3. c-kit protein in normal prostate was exclusively detected in mast cells by immunohistochemistry and in situ hybridization. However, c-kit transcripts, but not c-kit protein, were detected in low levels and with an heterogeneous pattern in basal epithelial cells of ducts and acini. c-kit in BPH was detected in epithelial cells in 9 of 53 (17%) specimens. c-kit protein expression in malignant epithelial cells was identified in 1 of 46 (2%) tumors. However, c-kit transcripts were detected in low levels by in situ hybridization in most of the tumors analyzed. KL protein and transcripts in normal prostate were detected in high levels in stroma cells. However, epithelial cells were unreactive for anti-KL antibody, but showed low levels of KL transcripts mainly in cells of the basal layer. Basal epithelial cells in hyperplastic glands showed KL expression in 13 of 53 (24%) specimens. KL protein in tumor cells was noted in 18 of 46 (39%) cases. c-kit transcripts were not found in normal prostate and in the 3 cancer cell lines analyzed by RT-PCR, however, it was present in cultured epithelial cells of BPH, and in cultures of stroma cells from both normal and BPH. The majority of cultured cell lines of epithelial and stromal origin displayed considerable levels of KL. In addition all prostate cell lines studied showed significant levels of KL transcripts. In summary, co-expression of c-kit and KL in a subset of BPH cases may suggest an autocrine mode of signaling. Data from this study reveals that altered patterns of c-kit and KL expression are associated with BPH and adenocarcinoma of prostate. It appears that KL induces mast cells proliferation and maturation and enhances their release of protease. This could explain the accumulation of mast cells at tumor sites, a phenomenon that was not observed in normal prostate or BPH samples.

ensp;Melorheostosis is an unusual mesenchymal dysplasia, which commonly presents on radiographs as longitudinal bars of hyperostosis in osseous structures. We present a case of melorheostosis in the lower extremity of a 20-year-old woman for which detailed radiologic- pathologic correlation was achieved due to amputation of the involved limb