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S B Keel

Publications and source records attributed to S B Keel.

At least 19 recordsLinked to original sources

Intra-articular lipoma with osteochondroid metaplasia in the knee joint.

We describe a case of lipoma with osteochondroid metaplasia in the knee joint. Although the location of the lesion and radiographic findings were unusual, computed tomography and magnetic resonance imaging were useful in characterizing adipose, cartilaginous and osseous tissue components within the lesion.

Humans↗

Orthopaedic implant-related sarcoma: a study of twelve cases.

Sarcoma developing in association with a metallic orthopaedic prosthesis or hardware is an uncommon, but well recognized complication. We review 12 cases of sarcomas arising in bone or soft tissue at the site of orthopaedic hardware or a prosthetic joint. Nine patients were male, and three were female. Their ages ranged from 18 to 85 (mean 55) years at the time of diagnosis of the malignancy. Five patients had undergone hip arthroplasty for degenerative joint disease, four had been treated with intramedullary nail placement for fracture, two had staples placed for fixation of osteotomy, and one had hardware placed for fracture fixation followed years later by a hip arthroplasty. The time interval between the placement of hardware and diagnosis of sarcoma was known in 11 cases and ranged from 2.5 to 33 (mean 11) years. The patients presented with pain, swelling, or loosening of hardware and were found to have a destructive bone or soft tissue mass on radiography. Two sarcomas were located primarily in the soft tissue and 10 in bone. Seven patients developed osteosarcoma, four malignant fibrous histiocytoma, and one a malignant peripheral nerve sheath tumor. All sarcomas were high grade. Three patients had metastatic disease at the time of diagnosis. Follow-up was available on eight patients: five patients died of disease 2 months to 8 years (mean 26 months) after diagnosis; two patients died without evidence of disease 7 and 30 months after diagnosis; and one patient is alive and free of disease 8 years after diagnosis. Sarcomas that occur adjacent to orthopaedic prostheses or hardware are of varied types, but are usually osteosarcoma or malignant fibrous histiocytoma. They behave aggressively and frequently metastasize. Clinically, they should be distinguished from non-neoplastic reactions associated with implants, such as infection and a reaction to prosthetic wear debris.

Adolescent↗

Fine-needle aspiration of dedifferentiated chondrosarcoma of the larynx.

We present a case of dedifferentiated chondrosarcoma of the larynx in which the dedifferentiated component was initially diagnosed by fine-needle aspiration (FNA). The patient was a 74-yr-old man who presented with difficulty breathing and an anterior neck mass. A CT scan demonstrated a 4.5-cm cartilaginous lesion involving the left thyroid cartilage, with an anterior soft-tissue component. Nine years prior, the patient had an incomplete resection of a low-grade chondrosarcoma at the same site. FNA was performed on the current lesion, demonstrating a high-grade spindle-cell sarcoma with a storiform pattern. The cytomorphology together with immunocytochemistry and electron microscopy were diagnostic of malignant fibrous histiocytoma (MFH), and synthesis of the clinical, radiographic, and cytomorphologic features resulted in a diagnosis of dedifferentiated chondrosarcoma. The cytologic diagnosis was histologically confirmed by laryngectomy. Although rare, dedifferentiated chondrosarcoma should be included in the differential diagnosis of high-grade sarcomas of bone and cartilage assessed by FNA.

Aged↗

Adult rhabdomyoma of the extremity: a case report and review of the literature.

The adult rhabdomyoma is a rare, benign skeletal muscle neoplasm that usually occurs in the head and neck. A case report of an adult rhabdomyoma arising in the thigh is presented with a review of the literature. This is the first case of an extremity adult rhabdomyoma to be reported. It is also the largest at 13 centimeters. Distinction from a highly differentiated rhabdomyosarcoma is important. Recent chromosomal studies suggest that the adult rhabdomyoma is a true neoplasm. Total resection is curative but the lesion may recur if incompletely excised.

Aged↗

Histological pattern of mandibular invasion by oral squamous cell carcinoma.

OBJECTIVE: Mandibular invasion by oral squamous cell carcinoma may progress by either an infiltrative or an erosive histological pattern. The infiltrative pattern is marked by nests and cords of tumor cells along an irregular tumor front, and the erosive pattern exhibits a broad, pushing tumor front. The objectives of this study were 1) to define the characteristics associated with each histological pattern of mandibular invasion, 2) to assess the relationship between pattern of invasion and clinical outcome as measured by death with disease and disease presence at last follow-up, and 3) to determine whether the cell cycle markers cyclin D1 and Ki-67 are associated with the histological pattern of invasion or are predictive of outcome. STUDY DESIGN: Retrospective study of 68 patients with mandibular invasion by oral cavity squamous cell carcinoma treated by mandibulectomy. METHODS: The clinical records, pathology reports, and original H&E-stained slides were reviewed for each patient. Immunohistochemical staining of cyclin D1 and Ki-67 was performed on slides cut from the paraffin blocks of these patients' specimens. RESULTS: The parameters found to be significantly associated with the infiltrative pattern of mandibular invasion included higher tumor grade, medullary space invasion, positive bone or soft tissue margins, history of previously failed treatment, and postoperative tumor recurrence. The infiltrative pattern had a positive bone margin rate of 47.6% and a primary site recurrence rate of 52.6%. In contrast, the erosive pattern had a positive bone margin rate of 4.9% and a primary site recurrence rate of 16.7%. The infiltrative pattern of invasion gave a fourfold increased risk of death with disease and disease presence at last follow-up in univariate and multivariate analyses when compared with the erosive pattern of invasion. The 3-year disease-free survival was 30% for the infiltrative pattern and 73% for the erosive pattern. The median disease-free survival was 1.5 years for the infiltrative pattern and 5.5 years for the erosive pattern. There was no correlation between cyclin D1 or Ki-67 staining and invasion pattern or clinical outcome. CONCLUSIONS: The infiltrative pattern of mandibular invasion by oral squamous cell carcinoma is correlated with a significantly worse prognosis when compared with the erosive pattern of invasion. The infiltrative pattern clearly exhibits a more aggressive behavior with an increased likelihood of positive margins, recurrence, death with disease, and shorter disease-free survival. We recommend that pathologists routinely comment on the histological pattern of invasion when reviewing oral squamous cell carcinoma with mandibular invasion.

Adult↗

Hemorrhagic epithelioid and spindle cell hemangioma: a newly recognized, unique vascular tumor of bone.

BACKGROUND: Epithelioid vascular tumors of bone are uncommon and include epithelioid hemangioma, epithelioid hemangioendothelioma, and epithelioid angiosarcoma. It is important to distinguish among them because they have significantly different biologic potential and require different forms of therapy. In the current study the authors describe six cases of a distinct benign epithelioid and spindle cell vascular tumor of bone that, because of their unusual morphology, were confused with aggressive vascular neoplasms. METHODS: Cases were retrieved from the surgical pathology files of the Department of Pathology or from the consultation files of one of the authors. Hematoxylin and eosin stained slides were examined. Immunohistochemistry was performed on two cases and electron microscopy was performed on one case. RESULTS: The tumors arose in the small bones of the hands and feet and the tibia. Three patients had multifocal bone disease at the time of presentation. Histologically, all lesions were comprised of lobules of spindle cells that grew focally in a fascicular pattern and were associated with abundant hemorrhage. Plump epithelioid cells were intermixed and were present focally in the interlobular areas as well, in which they lined larger, more well developed vascular spaces, often protruding into the vascular lumen in a "tombstone" fashion. Immunohistochemically and ultrastructurally the neoplastic cells had features of endothelium. One case was treated by amputation, one by resection, three by curettage, and one by curettage plus radiation therapy. None of the lesions was locally aggressive nor did any metastasize. CONCLUSIONS: The authors believe that hemorrhagic epithelioid and spindle cell hemangioma of bone is a histologically benign bone tumor. It should be distinguished from malignant epithelioid vascular tumors of bone, which have metastatic potential and need to be treated more aggressively.

Adolescent↗

Surgical treatment of primary pulmonary sarcomas.

OBJECTIVE: We sought to identify the long-term prognosis after surgical treatment for primary pulmonary sarcoma. METHODS: Twenty-three patients were retrospectively identified as having been treated surgically for primary pulmonary sarcoma between 1981 and 1996. The records of all patients were reviewed, and the histopathology reexamined by a pathologist. RESULTS: Fifteen patients were male and eight female; their ages ranged from 20 to 78 (mean 51) years. Tumors measured between 0.9 and 12.0 (mean 5.2) cm across the greatest diameter. The histologic diagnoses were malignant fibrous histiocytoma (8, three grade 1 or 2, two grade 3), synovial sarcoma (4), malignant schwannoma (3), leiomyosarcoma (3), and one case each of angiosarcoma, intimal sarcoma, epitheloid hemangioendothelioma, fibrosarcoma and primitive neuroectodermal tumor. Three patients were found to be unresectable. All three underwent radiation and chemotherapy. Lobectomies or bilobectomies were performed in 13 patients including two sleeve resections, one carinal resection, and one chest wall resection. Four patients underwent radical pneumonectomies. Three patients with invasion of the pulmonary artery, pulmonary veins or atrial wall underwent extended resections with the use of cardiopulmonary bypass. In two, a homograft was used to reconstruct the right ventricular outflow tract. Of the resected patients, six had a positive resection margin, and four had at least one positive lymph node in the specimen. Three patients underwent repeat pulmonary resections for recurrences. Eleven patients received postoperative chemotherapy and eight had radiation therapy. Follow-up was available on 22 patients, and ranged from 2 to 183 (mean 48) months; 14 patients are disease free, six died of disease, one died of surgical complications (operative mortality 5%), and two are alive with disease. Actuarial 3- and 5-year survival of the resected patients was 69%. Size and grade were not found to be correlated with significantly increased survival, but completeness of resection was (P<0.05). CONCLUSIONS: Resection of primary pulmonary sarcomas can produce an acceptable survival rate if the resection is complete. Cardiopulmonary bypass can be a useful adjunct when tumors involve a resectable area of the heart or great vessels.

Adult↗

Hyalinizing spindle cell tumor with giant rosettes: a report of three cases with ultrastructural analysis.

We report the light microscopic, ultrastructural appearance and immunohistochemical staining profile of three distinctive soft-tissue tumors recently designated hyalinizing spindle cell tumor with giant rosettes. The tumors occurred in two men, 41 and 54 years old, and one woman, 62 years old. Two tumors arose in the lower extremities and one in the upper arm. Two tumors were resected and measured 3 and 13.2 cm in greatest diameter; a biopsy only was done of the third tumor. Grossly, the tumors had a tan, pink, or white cut surface. The largest tumor exhibited central cystic change. Microscopically, they all displayed similar features and were composed of fibromyxoid regions, with areas of hyalinization in two tumors and focal ossification in one tumor. Scattered throughout each of the tumors were rosette-like structures in which neoplastic cells were arranged around a central collagenous core. Ultrastructurally, the neoplastic cells demonstrated the features of fibroblasts. In all tumors, there was abundant extracellular collagen fibers and in one there were large aggregates of amorphous extracellular external lamina-like material. The center of the rosette-like structures was composed of banded collagen fibers and the cells at the periphery of the rosettes had ultrastructural features similar to the neoplastic spindle cells located elsewhere in the tumor. Immunohistochemically, the tumor cells stained for vimentin. There was focal staining of the widely distributed spindle cells and cells that formed the rosettes for Leu-7, S-100 protein, and CD34. In one tumor, there was faint diffuse staining of the spindle cells for neuron-specific enolase. One tumor (with the amorphous extracellular material) stained for type IV collagen. There was no staining for desmin, muscle actin, smooth muscle actin, keratin, or epithelial membrane antigen. These results demonstrate that hyalinizing spindle cell tumor with giant rosettes is composed of fibroblasts. We did not demonstrate any ultrastructural or immunohistochemical differences between the spindle cells that comprised the majority of the mass and those that surrounded the rosette-like structures. There was no ultrastructural evidence of neural differentiation to explain the focal S-100 protein and Leu-7 staining of the tumor cells.

Adult↗

Chondrosarcoma of the base of the skull: a clinicopathologic study of 200 cases with emphasis on its distinction from chordoma.

Conventional chondrosarcoma (CSA) of the skull base is an uncommon neoplasm that can resemble chordoma, and indeed it is misdiagnosed frequently as such. This has important clinical implications, because when treated with similar aggressive treatment strategies, CSA has a much better prognosis than chordoma. In an effort to identify those morphologic and immunohistochemical features that help to identify conventional skull base CSA correctly and to understand its prognosis better, particularly compared with chordoma, when treated with surgery and proton beam irradiation, the authors performed a clinicopathologic analysis of 200 CSAs. The patients ranged in age from 10 to 79 years (mean, 39 years), 87 patients were male and 113 patients were female, and most presented with symptoms related to the central nervous system. Approximately 6% of the tumors arose in the sphenoethmoid complex, 28% originated in the clivus, and 66% developed in the temperooccipital junction. Histologically, 15 tumors (7.5%) were classified as hyaline CSA, 59 (29.5%) as myxoid CSA, and 126 (63%) as mixed hyaline and myxoid CSA. A total of 101 (50.5%) tumors were grade 1, 57 (28.5%) had areas of grades 1 and 2, and 42 (21%) were pure grade 2 neoplasms. The vast majority of patients originated from referring hospitals, and the diagnosis was changed prospectively at our institution to CSA from chordoma in 74 patients (37%). Of the tumors studied immunohistochemically, 96 of 97 (98.9%) stained for S-100 protein, 0 of 97 (0%) stained for keratin, and faint staining for epithelial membrane antigen was seen in 7 of 88 tumors (7.95%). All patients underwent high-dose postoperative fractionated precision conformal radiation therapy with a dose that ranged from 64.2 to 79.6 Cobalt-Gray-equivalents (median, 72.1 Cobalt-Gray-equivalents, given in 38 fractions. The 200 patients had a median follow-up of 63 months (range, 2.1 mos - 18.5 yrs). Tumor control was defined as lack of progression by clinical and radiographic assessment. Based on this definition, there were three local recurrences, and two of these patients died of tumor-related complications. The 5- and 10-year local control rates were 99% and 98% respectively, and the 5- and 10-year disease-specific survival rates were both 99%. In contrast to CSA, the 5- and 10-year survival rates of chordoma have been reported to be approximately 51 % and 35% respectively, and in our institution intensive treatment has resulted in 5- and 10-year progression-free survival rates of 70% and 45% respectively. CSA of the skull base can be distinguished reliably from chordoma, and this distinction is important because skull base CSA has an excellent prognosis when treated with surgery and proton beam irradiation, whereas chordomas have a substantially poorer clinical course despite similar aggressive management.

Adolescent↗

Chondromyxoid fibroma: a tumor showing myofibroblastic, myochondroblastic, and chondrocytic differentiation.

Chondromyxoid fibroma (CMF) is a rare primary benign tumor of bone that demonstrates variable histologic features and is often confused with chondrosarcoma. Although the chondroid elements in CMF have been reported to be S-100 protein positive and to have chondrocytic features ultrastructurally, the immunohistochemical and ultrastructural profile of CMF, especially with respect to the peripheral nonchondroid elements, has not been extensively studied. Formalin-fixed, paraffin-embedded tissue from 10 CMFs were stained immunohistochemically with antibodies to vimentin, desmin, muscle actin, smooth muscle actin, S-100 protein, and CD34. Six tumors were also examined ultrastructurally. The chondroid areas showed variable staining for S-100 protein but did not stain for muscle actin or smooth muscle actin. The peripheral areas surrounding the chondroid areas stained diffusely for smooth muscle actin and muscle actin but did not stain for S-100 protein. CD34 highlighted the extensive vascularity that was especially prominent in the peripheral areas; no tumor cells stained for CD34. There was no staining for desmin. Ultrastructural examination showed three different cell types. Some cells showed the classic features of chondrocytes, other cells had the features of myofibroblasts, and the third cell type had the features of both chondrocytes and myofibroblasts ("myochondroblasts"). These findings support the conclusion that CMF is a tumor showing myofibroblastic, myochondroblastic, and chondrocytic differentiation.

Actins↗

Primary pulmonary sarcoma: a clinicopathologic study of 26 cases.

The clinical and pathologic features of 26 primary pulmonary sarcomas were analyzed. Fourteen patients were male and 12 were female; ranging in age from 18 to 75 years (mean, 48 yr). The tumors measured from 0.9 cm in greatest diameter to filling the entire hemithorax. Thirteen tumors were in the left lung and nine in the right lung; one was bilateral, two were in the pulmonary artery, and the location of one tumor was not available. The histologic diagnoses were malignant fibrous histiocytoma (7), synovial sarcoma (6), malignant peripheral-nerve sheath tumor (3), leiomyosarcoma (3), angiosarcoma (2), intimal sarcoma (2), fibrosarcoma (2), and one case of epithelioid hemangioendothelioma. Immunohistochemical and ultrastructural examination supported these diagnoses. Morphologically, the differential diagnosis often included sarcomatoid carcinoma or desmoplastic malignant mesothelioma Patients were treated with surgery, chemotherapy, radiation therapy, or a combination of these. Follow-up was available for 22 patients and ranged from 2 to 183 months (mean, 45 mo). Fourteen patients are free of disease, four died of disease, three are alive with disease, and one died of surgical complications. A variety of sarcomas, especially malignant fibrous histiocytoma and synovial sarcoma, arise within the pulmonary parenchyma. These tumors have the potential to behave aggressively but can be cured by resection, with or without adjuvant therapy. Immunohistochemistry and electron microscopy can be helpful in distinguishing primary pulmonary sarcoma from other tumors in the differential diagnosis.

Adolescent↗

Malignant schwannoma of the uterine cervix: a study of three cases.

Pure sarcomas of the uterine cervix are rare; most of those reported have been leiomyosarcomas or rhabdomyosarcomas. Minimal data exists on malignant nerve sheath tumors in this site; only one typical example and one melanocytic example have been reported. We report three additional examples here in three patients 25, 65, and 73 years of age. The two older patients had vaginal bleeding and underwent hysterectomy as initial treatment. The youngest patient initially underwent only polypectomy. The tumors were 1.3, 4.4, and 5.0 cm in greatest dimension. The tumors were red-grey to white: two were polypoid and the third was ulcerated. The dominant microscopic appearance was that of cellular fascicles of spindle cells with hyperchromatic nuclei and eosinophilic cytoplasm. However, hypocellular areas were striking in each case; the hypocellular areas were fibromatous in two tumors and two had areas with a myxoid stroma (prominent in one). One tumor focally had cellular aggregates with a swirling pattern within a hypocellular background. Epithelioid foci in which tumor cells were rounded with conspicuous eosinophilic cytoplasm were focally prominent in one case. Mitoses were readily identified in each case. All three tumors were positive for S-100 protein and vimentin and negative for cytokeratin. HMB-45, and desmin. One case is recent and one patient had multiple metastases in the abdomen 2 years after hysterectomy. The patient treated initially by polypectomy underwent repeat local excision, followed by cone biopsy with positive margins, and then hysterectomy. She is clinically free of disease 15 months after diagnosis. Although the diagnosis of malignant schwannoma was suggested by the histologic features of the tumors, other diagnoses were entertained and immunohistochemistry was crucial in confirming the diagnosis. These tumors should be distinguished from other malignant spindle cell tumors of the cervix, such as leiomyosarcoma, endocervical "stromal sarcoma," and spindle cell melanoma, so their features, behavior, and optimal therapy can be further delineated.

Adult↗

Lipoma arborescens of the knee.

Lipoma arborescens is a rare intra-articular lesion, characterised by diffuse replacement of the subsynovial tissue by mature fat cells, producing prominent villous transformation of the synovium. The aetiology of this benign condition is unknown. We describe six cases involving the knee, discussing the symptoms, diagnosis and treatment.

Adipocytes↗