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C P Schwinn

Publications and source records attributed to C P Schwinn.

At least 19 recordsLinked to original sources
PubMed1994

Multicentric giant cell tumor: report of five new cases.

The typical giant cell tumor (GCT) is a solitary neoplams that occurs in the epiphysis or epimetaphysis of long bones. GCT is seen with a slightly increased frequency in females, and 70% of patients are between 20 and 40 years of age at the time of presentation. Multicentric giant cell tumor (MGCT; two or more centers) is an unusual variant of GCT. Patients with MGCT are likely to be younger than those with a solitary lesion. The multicentric variety is often of a higher stage at diagnosis and is more often associated with a pathological fracture than the unifocal tumor. We are reporting five new cases of MGCT, with a total of 21 tumors seen over a period of 25 years from 1967 to 1992.

Adolescent↗
PubMed1993

Bone remodelling in the presence of chondrosarcoma: histomorphometry.

Accurate knowledge of tissue changes near bone tumors can contribute to a better understanding of tumor behavior. We have used tumor ultrastructure and quantitative bone histomorphometry to evaluate local bone/tumor features associated with a low grade chondrosarcoma in a 39-year-old male. Three noninvolved sites and two sites near the tumor in the proximal femur were studied with bone morphometry. Bone near the tumor showed increased percent osteoid surface, percent osteoid volume and fraction of osteoid surface lined by osteoblasts compared to distant noninvolved sites. Both the number of osteoblasts and mean individual osteoblast size were significantly increased compared to noninvolved sites. Osteoclast number and percent osteoclast surface were also increased near the tumor. Ultrastructural studies of tumor tissue revealed two types of tissue: synthetic mesenchymal cells and cartilage tissue. Results indicate increased bone formation and resorption near the tumor. These local bone changes may possibly reflect responses to local tumor factors and depend on the extent of the tumor.

Adult↗
PubMed1993

Disappearing bone disease of the upper extremity.

Disappearing bone disease (Gorham's disease) is a rare clinical problem. The extensive bone loss seen with this entity makes it a difficult therapeutic problem, especially if contiguous bones are involved, which is a highly unusual occurrence. We report a case of disappearing bone disease involving the upper extremity and review the relevant literature.

Female↗
PubMed1992

Case report 749: Primary glomus tumor of bone.

We report a case of primary intraosseous glomus tumor in a 30-year-old man who was found to have an expanding, lytic lesion in the distal phalanx of his left thumb. The histological appearance was atypical in that areas of myxoid stroma resembled chondroid material. The unusual location and microscopic appearance caused diagnostic problems. Immunohistochemical studies, including strong positive staining for MSA and negative staining for keratin and S-100 protein, were helpful in establishing the correct diagnosis.

Adult↗
PubMed1992

Bone response to invading tumors with spindle cell components: a report of findings in two patients.

Two case studies are presented in which quantitative bone histomorphometry is used to analyze bone changes in adult patients with diagnosed spindle cell sarcoma. Three tumor-involved sites and one noninvolved site from the iliac crest of patient 1 were evaluated. In the involved sites the percentage trabecular bone volume (11.0%) and the number of osteoblasts (0.6 cell/mm2) were significantly reduced, osteoid volume was significantly increased (8.1%), and woven osteoid was present. The total eroded surface (6.8%) was also significantly increased. In the noninvolved site the number of osteoblasts was decreased and both the percentage eroded and percentage osteoclast surfaces were increased. In the femoral epicondyle specimen from patient 2 the number of osteoblasts was 27.0 cells/mm2, percentage osteoid volume was 18.4%, percentage osteoid surface was 62.9%, and osteoid thickness was 20.0 microns. In tumor-involved sites in both patients indices of active bone resorption were similar and normal. These two case studies indicate that (1) distinctive morphologic changes occur in bone invaded by spindle cell sarcoma, and that (2) changes affect bone formation to a greater extent than bone resorption. Bone alterations are probably local in nature and related to the extent and duration of tumor invasion and the influence of local tumor factor(s).

Adult↗
PubMed1990

In vivo wear of titanium-alloy hip prostheses.

We examined samples of tissue and components that had been removed during twenty revisions of total hip arthroplasties in which a titanium-alloy femoral component had been used. Minute amounts of metallic debris were detected in the tissues from two patients. The amounts of polyethylene and methylmethacrylate debris and the histological reactions in the tissues corresponded closely with those reported in earlier studies of total hip prostheses made of stainless steel or cobalt-chromium alloy.

Acrylates↗
PubMed1988

Diaphyseal intraosseous ganglion.

Ganglion cysts of bone are noted to occur most often in the metaphysis of epiphysis of a long bone. A unique ganglion cyst, developing in a diaphyseal location, was excised from the leg of a 14-year-old boy. The follow-up examination showed no recurrence one year following surgery.

Adolescent↗
PubMed1987

Alteration in osteoblast cell number and cell activity in the presence of invading malignant fibrous histiocytoma.

Correct prediction of tumor behavior and interpretation of local factors in the tumor microenvironment rely in part upon accurate determination of tissue changes after tumor invasion. The authors examined local bone changes in primary malignant fibrous histiocytoma (MFH) of bone in a 59-year-old woman. Three noninvolved and three tumor-involved sites were evaluated by quantitative determinations of bone structural and dynamic features. Compared to noninvolved sites, tumor-involved bone was characterized by significantly increased osteoblast index (89.4 +/- 15.6 [mean +/- SEM] versus 7.3 +/- 6.0, P = 0.008), percent osteoid area (12.1 +/- 2.7 versus 1.2 +/- 0.5, P = 0.02), percent of trabecular surface covered by osteoid (70.0 +/- 6.0 versus 14.5 +/- 4.8, P = 0.002), and percent osteoid lined by osteoblasts (36.4 +/- 3.6 versus 3.7 +/- 3.0, P = 0.002). Bone 7.8 mm distant from invading tumor cells showed features characteristic of noninvolved sites, whereas bone completely surrounded by tumor showed markedly decreased osteoblast features. Osteoblast function also was affected by tumor; the amount of matrix laid down per day bore a significant positive correlation with the osteoblast index. These data indicate the following: distinctive bone morphologic changes occur in situ during invasion by MFH; changes affect aspects of bone formation but not resorption during invasion; both osteoblast number and osteoblast activity are significantly altered; and changes are local in nature and probably reflect the osteoblast response to local tumor factor(s) and are dependent upon the extent of tumor invasion.

Bone Neoplasms↗
PubMed1979

Chordoma. A clinicopathologic study of metastasis.

Thirty cases of chordoma were reviewed with respect to the incidence of distant metastases. Follow-up information was obtained in 27 (90%), and the incidence of metastases was approximately 30%. The sites of the metastasizing primary tumors were predominantly sacral and vertebral. The sites of the metastases were predominantly skin and bone, although metastases were found in the lungs and lymph nodes. In two of the three patients with dermal metastases, the metastases were present prior to the diagnosis of the primary lesions. All three dermal metastases were initially diagnosed as mixed tumors of the skin, and all three patients had at least four such lesions of the skin. Accurate prediction of which chordomas will eventually metastasize is difficult. Clinically, local aggressiveness and radiotherapy were positively correlated with this ability; histologically, more anaplastic chordomas were more likely to metastasize.

Adolescent↗
PubMed1979

Tenosynovial chondromatosis in the hand.

Eight cases of tenosynovial chondromatosis in the hand were compared with twelve cases collected from the literature and available data on eleven cases showed that in three there were recurrences. No patients had metastatic lesions during a follow-up period averaging 7.8 years. Based on these data, we concluded that a moderately radical en bloc excision is adequate treatment for tenosynovial chondromatosis in the hand.

Adult↗
PubMed1976

The ultrastructure of osteosarcoma. A review of twenty cases.

The ultrastructural features of 20 cases of osteosarcoma are discussed. Characteristically, the malignant cells (osteoblasts) contained large quantities of dilated, anastomosing rough endoplasmic reticulum, ofter forming large lakes. Mitochondria were sparse. Similar features are seen in osteoblasts in normal developing bone. Marked ultrastructural similarities of cells from chondrosarcomatous, fibrosarcomatous and typical osteosarcomatous areas of these tumors strongly supports the concept that these neoplastic cells all arise from the same progenitor cell. Malignant giant cells were readily differentiated from benign osteoclasts. The most significant ultrastructural findings were the varying degrees of calcification in the intercellular areas (osteoid), ranging from an extensive dense deposition of hydroxyapatite crystals which obscured the underlying collagen fibers, to focal collectors, or puffs, of slender needle-shaped hydroxyapatite crystals deposited on or along collagen fibers. The earliest apparent evidence of calcification was the presence of small electron-dense particles on or in collagen fibers.

Adolescent↗