[The use of radiotherapy in the prevention of heterotopic ossification in patients with total hip replacement]. / L'uso della radioterapia nel prevenire le ossificazioni eterotopiche nei pazienti sottoposti a intervento di protesi d'anca.

In order to prevent heterotopic ossification (HO) after total hip replacement, 21 high risk hips were irradiated pre- and postoperatively to prevent heterotopic bone formation in the St. Paul Department of Radiation Oncology from 1993 to September, 1995. Eighteen hips in 15 patients were eligible for analysis with a minimum follow-up of 3 months. All the hips in our series were at high risk of heterotopic bone formation. All assessable patients had radiographic findings of ipsilateral or contralateral previous ectopic bone formation, 8 following total hip arthroplasty, 4 following trauma and 3 had heterotopic osteoarthritis. Four hips were treated 46 hours preoperatively, while all the others were treated on the first postoperative day. The irradiation field was limited to the hip region and radiation exposure to a rectangular field, ranging in size from 8 x 12 to 10 x 15 cm, to include the lateral aspect of the greater trochanter. We used a cobalt-60 unit. Opposed anterior-posterior fields were irradiated at midplan, with a source-to-axis distance of 80 cm; the dose was 6-8 Gy in one fraction. Preoperative irradiation appeared as effective as postoperative treatment, and more comfortable for the patients. There were neither side-effects nor failure of ossification. The treatment appeared effective in the prophylaxis of HO in 88% of patients, with clinical advantages in 67% of them.

Effect of recombinant human TNF on human ovarian cancer cell lines.

Ovarian cancer is the second most common gynecologic malignancy. Standard therapeutic approaches to this disease, surgery followed by chemotherapy, have produced response rates of up to 80%. However, the five-year survival rate remains around 30%. Recently, Tumor Necrosis Factor (TNF) has received attention as either an alternative or an associated agent for chemotherapy of ovarian cancer. TNF is known to have direct cytotoxic and cytostatic effects on a variety of transformed cell lines "in vitro". Furthermore, TNF is known to enhance significantly the "in vitro" effects of a class of chemotherapeutic agents, specifically those targeted at DNA topoisomerase II. In this work we have investigated TNF-induced cytotoxicity in four established human epithelial ovarian cancer cell lines: A-2774; SV-626; SKOV-3 and Pa-1. TNF mediated cytotoxic activity was observed in a range of concentrations between 1 U/ml and 10-3 U/ml. A-2774 and SV-626 were the two most sensitive lines, especially when exposed to high concentrations of TNF.

[Use of reconstituted basal membranes for the study of invasion of human tumor cells: current status and future prospects]. / Uso di membrane basali ricostituite per lo studio dell'invasione di cellule tumorali umane: stato attuale e prospettive future.

Tumor metastasis is the major cause of death of oncology patients. One of the characteristic properties acquired by the metastatic cell is the ability to cross basement membranes. These are compartments of extracellular matrix composed largely by collagen type IV, laminin and a heparan sulphate proteoglycan. Here we review the use of a reconstituted basement membrane (Matrigel) in the Boyden chamber assay (Chemoinvasion Assay) for the assessment of the invasiveness of tumor cells of human origin. The possibility of using this test for the rapid evaluation of human tumor specimens from operated patients is discussed.