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Biomedical subjects

F Schajowicz

Publications and source records attributed to F Schajowicz.

At least 37 records · Page 2Linked to original sources

Spontaneous fractures of uninvolved bones in patients with Paget's disease during unduly prolonged treatment with disodium etidronate (EHDP).

Three patients with Paget's disease of bone were treated by disodium etidronate (EHDP) without interruption during periods of 18 to 30 months. In one case the daily dose was also unduly high (approximately equal to 18 mg/kg/day). A moderate to conspicuous diminution of the renal function was observed in all cases. The three patients developed skeletal pain in a gradual but progressively severe pattern. Seven nontraumatic fractures in nonpagetic bones were encountered. EHDP produces blockage of bone mineralization and excessive suppression of bone remodeling, therefore increasing the risks of fracture. EHDP affects not only pagetic bones but normal skeleton. A baseline evaluation of the renal function might help to identify those patients with greater risk to develop skeletal side effects during EHDP treatment.

Aged↗

Virus-like intranuclear inclusions in giant cell tumor of bone.

An ultrastructural study of 13 cases of typical giant cell tumor of bone (GCT) revealed the presence of virus-like intranuclear inclusions (INI), morphologically identical to those reported in Paget's disease of bone. In two giant cells of two different patients, INI were found only after careful survey of a great number of cells. This finding, coupled with the scarcity of GCT with similar inclusions reported in the literature, reveals the extreme rarity of this finding and leaves open to discussion the specificity of these INI even in Paget's disease, as well as the possible etiological significance in giant cell tumor of bone.

Bone Neoplasms↗

Sarcoma complicating Paget's disease of bone. A clinicopathological study of 62 cases.

Out of 21 900 cases filed at the Latin-American Registry of Bone Pathology between April 1940 and July 1981, there were 987 with Paget's disease (4.51 per cent); 62 of these (6.28 per cent) were complicated by sarcoma and two were associated with giant-cell tumours of bone (osteoclastoma) without signs of malignancy. There was a slight predominance of men and the ages ranged from 45 to 87 years, with an average of 66 years. The most frequent sites were the femur (23 cases), the humerus (nine), the pelvis (10), and the tibia (nine). The low incidence of vertebral involvement (five cases) is noteworthy and is in sharp contrast to uncomplicated Paget's disease. The most common tumour type was osteosarcoma (39 cases), followed by fibrosarcoma (15 cases); other varieties (chondrosarcoma, malignant fibrous histiocytoma and reticulum-cell sarcoma) were much rarer. Most of the sarcomata occurred when the Paget's disease was polyostotic. Tumours often developed simultaneously, or at short time intervals, in the same or different bones; these bones had, in all cases, been affected by Paget's disease. The histological features of the osteosarcomata were characteristic, with large numbers of osteoclast giant cells, alternating with atypical osteoblasts, thus exaggerating the anarchic remodelling process of Paget's disease. The neighbouring areas of the pagetic bone showed an increased number of osteoclasts. These facts suggest a possible pathogenetic relationship between sarcoma and Paget's disease; the possibility of both processes having a viral aetiology is discussed.

Adult↗

Current trends in the diagnosis and treatment of malignant bone tumors.

After a review of the potential of current methods of investigation and of the slightly modified WHO bone tumor classification, the following neoplastic lesions, the diagnosis and treatment of which still present some unsolved problems, are described in detail: giant cell tumor (osteoclastoma); osteosarcoma, with special reference to malignant osteoblastoma; periosteal osteosarcoma and its disputed relation with or supposed identity to juxtacortical chondrosarcoma; Ewing's sarcoma; and malignant fibrous histiocytoma.

Biopsy↗

Microspectrophotometric quantitation of DNA in bone tumors with giant cells (osteoclastoma, osteosarcoma and chondroblastoma).

A microspectrophotometric study of DNA content was carried out on cells from three types of bone tumor--osteoclastoma, chondroblastoma, and osteosarcoma--in all of which the formation of multinucleated giant cells occurs. Giant cells of osteoclastic type were present in all the tumors, with contents of DNA which were constant, uniform and diploid in character for each nucleus individually considered. Since there were no nuclei with reduced or increased content of DNA, mitotic proliferation or gemmation can be excluded. Instead, the evidence suggests the formation of giant cells through a mechanism of cellular fusion. In contrast, the stromal cells of the osteoclastomas and the chondroblastomas gave evidence of DNA synthesis, thus proving their proliferative capacity in both tumors. The osteosarcomas showed a very irregular distribution of DNA, and generally the nuclear content of DNA exceeded the diploid DNA content.

Bone Neoplasms↗

Juxta-articular bone cysts (intra-osseous ganglia): a clinicopathological study of eighty-eight cases.

The clinical, radiographic and pathological features of eighty-eight cases of histologically verified intra-osseous ganglia in eighty-three patients are described. All were located in the subchondral bone adjacent to a joint and most frequently involved the hip, the ankle (medial malleolus), the knee and the carpal bones. Forty-seven of the eighty-three patients were male and all the patients were between fourteen and seventy-three years of age, with an average age of forty-one years. There are two fundamental types of intra-osseous ganglia, one apparently arising by penetration of juxta-osseous ganglion into the underlying bone, a mechanism proved in fourteen of our eighty-eight cases (16 per cent); in the remaining seventy-four cases, the ganglion cyst was primarily intra-osseous ("idiopathic"). The initial cause of the intramedullary mucoid degeneration is discussed. We believe that mechanical stress and repeated minor trauma near the surface of the bone may lead to intramedullary vascular disturbance with consequent foci of aseptic bone necrosis. The revitalisation of these areas causes fibroblastic proliferation, followed by mucoid degeneration of the connective tissue, possibly due to some unknown local factor. Curettage or excision is usually effective, and recurrence (only four cases) is exceptional.

Acetabulum↗

Intracortical haemangioma simulating osteoid osteoma.

A case of intracortical haemangioma in the tibial diaphysis is reported. The radiological and macroscopic features were identical with osteoid osteoma. In view of this similarity, haemangiomata, despite their rarity at this site, must be considered in the differential diagnosis of osteoid osteoma.

Bone Neoplasms↗

Cystic angiomatosis (hamartous haemolymphagiomatosis) of bone. A clinicopathological study of three cases.

The clinical and radiological features in three cases of cystic angiomatosis of bone are reported. Although these features are generally diagnostic except from histiocytosis X, the definitive diagnosis must be established by a pathological study, preferably of a segment of an involved rib or fibula. The prognosis varies according to the type of clinical presentation-in particular upon whether the lesions are solely skeletal or whether there is extraskeletal visceral involvement. Whereas these last cases may often prove fatal, those with only skeletal involvement have a favourable prognosis: indeed, the cystic bone lesions may regress without any treatment, as occurred in some cases reported in the literature and in two of our three cases.

Adolescent↗

Juxtacortical chondrosarcoma.

The features are described of seven cases of "juxtacortical" chondrosarcoma, the term introduced by Jaffe for a rare but distinct entity and now accepted in the World Health Organisation classification as preferable to the term "periosteal" chondrosarcoma. In all cases the lesion involved the shaft of a long bone, most often the femur, and in two cases two different long bones were affected. Six of the seven patients were male and all were in the second decade. The characteristic appearance was that of a small tumour adjacent to the cortex with areas of spotty calcification often accompanied by radiating bone spicules perpendicular to the bone shaft and a typical Codman's triangle. Histologically all the tumours showed a cartilaginous lobular pattern, well limited on the surface and seldom infiltrating the cortex; areas of spotty calcification and enchondral ossification were often present but tumour osteoid and bone were conspicuously absent. Despite the ominous histological aspect, the prognosis proved to be relatively favourable compared with the usual central chondrosarcoma of a similar grade of malignancy.

Adolescent↗

Familial idiopathic hyperphosphatasia: a study of two young siblings treated with porcine calcitonin.

A study of two siblings with a severe infantile form of familial idiopathic hyperphosphatasia is reported. A girl aged one year was followed for two years while receiving intermittent treatment with porcine calcitonin. This induced a clinical remission, a reduction of both the high serum level of alkaline phosphatase and the raised urinary excretion of hydroxyproline, and a remarkable improvement in bone structure as seen radiologically. Her sister aged two months received porcine calcitonin for three weeks, during which clinical improvement, no change in the serum level of alkaline phosphatase and a marked decrease of the excretion of hydroxyproline were recorded.

Alkaline Phosphatase↗

Metal carcinogenesis: a study of the carcinogenic activity of solid metal alloys in rats.

The carcinogenic activity of seven metallic alloys was studied by implanting solid rods of each alloy in the gluteal muscles of Sprague-Dawley rats which were killed after twenty-four months. When the number of tumors in these rats was compared with the numbers in rats not operated on, in rats which had a sham operation, and in rats implanted with Silastic rods, no statistically significant differences in the incidences of the tumors in the several groups were found.

Alloys↗

Aspiration (puncture of needle) biopsy in bone lesions.

In certain bone tumor cases bone puncture is more profitable than sample excision. Whenever necessary we are using both methods in our practice. The results of 7165 puncutre biopsies are presented. A definite diagnosis by needle biopsy could be established in 771 tumors, including 254 myelomas and 174 osteogenic sarcomas. The aspiration or needle biopsy will require some experience not only on the part of the pathologist, but also of the surgeon. The pathologist must be sufficiently familiar with the clinical and radiographic evidence before interpreting the cytologic or the histopathologic specimen.

Biopsy↗

Malignant osteoblastoma.

The clinical, radiographic and pathological features are described of eight cases of a bone tumour which we propose to classify as "malignant osteoblastoma". It presents the characteristics of genuine osteoblastoma but of an aggressive pattern, with more abundant and often plump hyperchromatic nuclei, greater nuclear atypia, and numerous giant cells of osteoclastic type. This rare tumour is regarded as the malignant counterpart of osteoblastoma and appears to be only locally aggressive. It should be separated from conventional osteosarcoma not only because of its peculiar histological pattern, but also because of its different clinical and radiological features and better prognosis. Thus seven of the eight patients were alive and free of disease from one and a half to eleven years after the initial surgical treatment, which in only two cases included amputation. Excision or block resection is the preferred method of treatment.

Adolescent↗