VALUE OF PROSTATE SPECIFIC ANTIGEN IN PREDICTING THE EXISTENCE OF BONE METASTASIS IN SCINTIGRAPHY

ABSTRACT Objective: Evaluate the ability of serum concentration of prostate specific antigen (PSA) between 2 cutting points to predict the existence of bone metastasis confirmed by bone scintigraphy in man with prostate cancer. Materials and Methods: Two hundred and fourteen consecutive patients with prostate cancer were evaluated during the present study in the period from 1998 to 2001. From all patients, PSA serum concentrations and bone scintigraphy were obtained. For the study, 2 cutting points of PSA (10 and 20 ng/mL) were adopted to predict the existence of bone metastasis. Results: From the 214 patients, 35 (16.3%) presented positive scintigraphic examinations for the presence of bone metastasis. No patient presented bone metastasis in scintigraphy if having PSA < 10 ng/mL, and in only 1 patient (0.46%) with bone metastasis PSA concentration was < 20 ng/mL. Therefore, when the cutting point adopted for PSA serum concentration was 10 ng/mL, a negative predictive value for bone metastasis was 100% with sensitivity rates of 100%. Nevertheless, the positive predictive value and the specificity of the method were, respectively, 24.5% and 39.7%. When the cutting point of PSA serum concentration was 20 ng/mL, an increment was observed in rates of positive predictive value and specificity (41.5% and 73.2%), respectively, without substantial changes in negative predictive value (99.2%) and sensitivity (97.1%) of the method. Conclusions: Data of present study allow for the conclusion that PSA serum concentration over 20 ng/mL was a more accurate cutting point than PSA serum concentration over 10 ng/mL to predict the presence of bone metastasis in scintigraphy

Value of prostate specific antigen in predicting the existence of bone metastasis in scintigraphy

OBJECTIVE: Evaluate the ability of serum concentration of prostate specific antigen (PSA) between 2 cutting points to predict the existence of bone metastasis confirmed by bone scintigraphy in man with prostate cancer. MATERIALS AND METHODS: Two hundred and fourteen consecutive patients with prostate cancer were evaluated during the present study in the period from 1998 to 2001. From all patients, PSA serum concentrations and bone scintigraphy were obtained. For the study, 2 cutting points of PSA (10 and 20 ng/mL) were adopted to predict the existence of bone metastasis. RESULTS: From the 214 patients, 35 (16.3%) presented positive scintigraphic examinations for the presence of bone metastasis. No patient presented bone metastasis in scintigraphy if having PSA < 10 ng/mL, and in only 1 patient (0.46%) with bone metastasis PSA concentration was < 20 ng/mL. Therefore, when the cutting point adopted for PSA serum concentration was 10 ng/mL, a negative predictive value for bone metastasis was 100% with sensitivity rates of 100%. Nevertheless, the positive predictive value and the specificity of the method were, respectively, 24.5% and 39.7%. When the cutting point of PSA serum concentration was 20 ng/mL, an increment was observed in rates of positive predictive value and specificity (41.5% and 73.2%), respectively, without substantial changes in negative predictive value (99.2%) and sensitivity (97.1%) of the method. CONCLUSIONS: Data of present study allow for the conclusion that PSA serum concentration over 20 ng/mL was a more accurate cutting point than PSA serum concentration over 10 ng/mL to predict the presence of bone metastasis in scintigraphy

Efeitos do alopurinol sobre a lipoperoxidação de membranas celulares renais na síndrome da isquemia e reperfusão : estudo experimental em ratos

Objetivo: Vários estudos têm demonstrado que Radicais Livres de Oxigênio (RLO) contribuem para o dano celular decorrente da isquemia e reperfusão. Este estudo foi desenvolvido como o objetivo de avaliar os efeitos da isquemia e reperfusão renal em ratos, tratados ou não com alopurinol, sobre a lipoperoxidação (LPO) das membranas celulares renais. Método: Foram usados ratos Wistar distribuídos em 4 grupos e submetidos a períodos de isquemia e reperfusão renal ou não, dependendo do grupo. Também foram submetidos ou não a tratamento com alopurinol na dose de 50 e 150 mg/Kg por via intraperitoneal, 5 e 1 horas antes do procedimento. Na avaliação da lipoperoxidação utilizou-se os métodos do TBARS e QL.Resultados: Os resultados demonstraram aumento da LPO nos animais submetidos a isquemia e reperfusão renal. No entanto, estes efeitos deletérios foram reduzidos com o pré-tratamento com alopurinol (p<0,05). Conclusão: O dano causado em animais submetidos a isquemia e reperfusão renal pode ser demonstrado e quantificado pela LPO. Além disso, o alopurinol demonstrou proteção renal contra o dano decorrente desta síndrome, diminuindo a LPO nestes animais. Estes resultados sugerem que a via da xantina oxidase é uma das mais importantes rotas metabólicas envolvidas na geração de RLO, estes responsáveis em parte pelos danos funcionais do rim na síndrome da isquemia e reperfusão deste órgão.Background:Evidence has accumulated that oxygen free radical (OFR) contribute to the cellular damage induced by ischemiareperfusion. This study was undertaken to determine the effects of renal ischemia-reperfusion in rats, treated or not with allopurinol evaluating the lipid peroxidation (LPO) of renal cellular membranes. Method: Wistar rats were divided into 4 groups (n=10) and submitted to 50 minutes of renal ischemia and reperfusion and treated or not with allopurinol (50 and 150 mg/Kg of body, 5 and 1 hour before ischemia, respectively). The lipid peroxidation was assessed by TBARS method (Thiobarbituric acid reactives substances) and CL method (Chemiluminescence). Results:The results showed that animals submitted to renal ischemia-reperfusion had renal LPO damage. These effects of ischemia and reperfusion were reduced by treatment with allopurinol (p<0,05). Conclusion: These results suggest that xanthine oxidase is one of the most important pathway envolved in the generation of OFR and chemical reactives elements with injury potencial at the renal cellular membranes due to ischemia-reperfusion syndrome. At least, allopurinol showed benefical effects preventing damage due to renal ischemiareperfusion injury