L. Martínez-Piñeiro

Determination of the Percentage of Free Prostate–Specific Antigen Helps to Avoid Unnecessary Biopsies in Men with Normal Rectal Examinations and Total Prostate–Specific Antigen of 4–10 ng/ml

Objective: To assess the usefulness of measuring the percentage of free prostate–specific antigen (PSA) in serum to reduce the number of prostate biopsies in men with serum PSA levels between 4 and 10 ng/ml and benign prostate examinations. Materials and Methods: The percentage of free PSA (Immulite®) in serum was analyzed prospectively in 180 men with benign digital rectal examinations and total PSA serum levels of between 4 and 10 ng/ml. All patients underwent ultrasound–guided sextant prostatic biopsies. Sensitivity, specificity and positive and negative predictive values were calculated as well as the percent of patients in which biopsies could have been avoided for various cutoff values of the percentage of free PSA as an indicator for biopsy. Influence of age in the determination of cut points was evaluated. Results: Cancer was detected in 22.2% (40/180) of the patients. Mean percentage of free PSA was 13.4% in patients with cancer and 18.9% in patients with benign prostatic hyperplasia (p = 0.001). Using a percentage of free PSA cutoff of 22% or less as a criterion for performing prostatic biopsy would have detected 95% of cancers, avoided 25% of benign biopsies and yielded a positive predictive value of 29% in patients who underwent biopsy. Mean percent of free PSA values increased as mean subject age increased, influencing the calculation of cut points, sensitivity and specificity. Leaving the cut point constant across all age groups will oblige older patients to undergo an increased number of unnecessary biopsies, although allowing for higher sensitivity in younger men. Conclusions: Measurement of the percentage of free serum PSA improves specificity of prostate cancer detection in patients with elevated total serum PSA levels and benign prostate examinations. Subject age seemed to influence the determination of optimal cut points.

Preliminary Results of a Comparative Study with Intracavernous Sodium Nitroprusside and Prostaglandin E1 in Patients with Erectile Dysfunction

We compared the effect of intracavernous administration of sodium nitroprusside, a nitric oxide donor and, therefore, stimulator of the cyclic guanosine monophosphate pathway, with the activity of prostaglandin E1, which is a stimulator of the cyclic adenosine monophosphate pathway. To date 105 patients with erectile dysfunction have entered the study. As part of the diagnostic evaluation every patient received an intracavernous injection of 20 micrograms prostaglandin E1 and a second injection of sodium nitroprusside at different concentrations (100 micrograms in 10 patients, 300 micrograms in 60 and 400 micrograms in 35). Sodium nitroprusside at a dose of 100 micrograms was not effective for inducing erections. Prostaglandin E1 induced better responses overall than sodium nitroprusside at 300 and 400 micrograms (p < 0.001). The overall duration of erections was also significantly longer with prostaglandin E1 (mean 88.5 minutes) than with 300 micrograms sodium nitroprusside (mean 50.8 minutes, p < 0.001) but did not reach statistical significance compared to 400 micrograms sodium nitroprusside (mean 42.2 minutes). Side effects were minimal with both drugs. Although sodium nitroprusside has several benefits over prostaglandin E1 for intracavernous use (such as lower cost, absence of local pain and shorter action, allowing detumescence after orgasm and decreasing the risk of priapism), prostaglandin E1 still remains the agent of choice for intracavernous use.

Prospective Comparative Study with Intracavernous Sodium Nitroprusside and Prostaglandin E1 in Patients with Erectile Dysfunction

Purpose: To compare the effectiveness of intracavernous administration of sodium nitroprusside and prostaglandin E1 to induce penile erection in men with erectile dysfunction. Material and Methods: 100 patients with erectile dysfunction entered the study prospectively. As part of the diagnostic workup, each patient received an intracavernous injection of 20 µg prostaglandin E1 and a second injection of 600 µg sodium nitroprusside 1–7 days later. A tourniquet was placed at the base of the penis before each injection. The data recorded included time required to initiate tumescence, local and systemic side effects, objective and subjective quality of erections, duration of tumescence and patient satisfaction by means of a personal questionnaire. Results: Prostaglandin E1 induced better overall responses than sodium nitroprusside, the difference being almost significant (p = 0.055). The overall duration of erections was also significantly longer with prostaglandin E1 (mean 81.3 min) than with sodium nitroprusside (mean 65.4 min; p < 0.04). 67% of the patients considered the erections induced with prostaglandin E1 to be of better quality than those with sodium nitroprusside, and only 11% stated that sodium nitroprusside was superior. Side effects were minimal with both drugs, the most frequent side effect being systemic hypotension, which was induced by sodium nitroprusside in 7% of the patients. Conclusions: The moderate risk of systemic hypotension and the lower potency of sodium nitroprusside to induce erections compared to prostaglandin E1 rules out sodium nitroprusside as a routine alternative intracavernous drug in men with erectile dysfunction at the doses employed. Sodium nitroprusside, however, could be used in patients who have intolerance or penile pain with intracavernous prostaglandin E1.

Probability of prostate cancer as a function of the percentage of free prostate-specific antigen in patients with a non-suspicious rectal examination and total prostate-specific antigen of 4–10 ng/ml

Our aim was to assess the usefulness of measuring the percentage of free prostate specific antigen (PSA) in serum in relation to reducing the number of prostate biopsies in men with benign prostate examinations and serum PSA levels between 4 and 10xa0ng/ml. The percentage of free PSA (Immulite) in serum was analyzed prospectively in 500 men, all of whom underwent ultrasound-guided sextant prostate biopsies. Cancer was detected in 21.4% (107/500) of the patients. Using a free PSA cutoff of ≤23% as a criterion for performing prostate biopsy would have detected 94.4% of cancers, avoided 18.8% of benign biopsies and yielded a positive predictive value of 25.3%. The percentage of free PSA increased with prostate volume. Mean total PSA and mean free percent PSA values increased as patient age increased, influencing the calculation of cutoff values, sensitivity and specificity. PSA density had a sensitivity and specificity not significantly different than the percentage of free PSA. Measurement of the percentage of free serum PSA improves the specificity of prostate cancer detection in patients with elevated total serum PSA levels and benign prostate examinations.

Molecular staging of prostatic cancer with RT-PCR assay for prostate-specific antigen in peripheral blood and lymph nodes: 5 Year follow-up

OBJECTIVEnThirty percent of patients with localized prostate cancer undergoing radical prostatectomy experience biochemical recurrence with rising serum prostate-specific antigen (PSA). More than 50% of these develop distant metastases.nnnMETHODSnPresence of PSA mRNA in pathologically normal pelvic lymph nodes from 154 patients undergoing radical prostatectomy was investigated with non-quantitative PSA reverse transcriptase polymerase chain reaction (RT-PCR). In 135 of these patients preoperative serum PSA RT-PCR was also assessed. RT-PCR positivity was correlated with biochemical recurrence and compared with other clinical risk factors.nnnRESULTSnAt a median follow-up of 58 months the biochemical failure-free survival of patients with positive versus negative lymph node RT-PCR was 68.4% and 76.7% respectively (p=0.2). Biochemical failure-free survival was not influenced by the serum PSA RT-PCR result either (72.3% versus 72.6%). Surgical margin status, preoperative serum PSA, pT category and Gleason score were independent prognostic risk factors for biochemical recurrence with a hazard ratio of 5.48, 2.56, 2.56 and 2.13 respectively.nnnCONCLUSIONSnAt 5 year follow-up after radical prostatectomy, both serum and lymph node RT-PCR are not correlated with biochemical failure-free survival. Established clinical risk factors have a much stronger impact on biochemical recurrence.

Valoración y tratamiento de las heridas penetrantes del riñón

El traumatismo penetrante del rinon es menos comun que el traumatismo cerrado. Sin embargo, su incidencia ha aumentado en las ultimas decadas debido al incremento de la violencia urbana. Las principales causas de traumatismo penetrante son las heridas por arma blanca y por arma de fuego, con una proporcion mas alta de lesiones renales en el segundo caso. El tratamiento del traumatismo renal ha avanzado en los ultimos anos. Antes se indicaba cirugia de entrada en la mayoria de los casos, lo que se acompanaba de un indice elevado de nefrectomias. En la actualidad, el desarrollo de las nuevas tecnicas de diagnostico por imagen disponibles en los servicios de urgencia permite, en algunos casos, la abstencion terapeutica y el seguimiento estricto de los pacientes con el fin de preservar el rinon. La principal exploracion diagnostica es la tomografia computarizada (TC) con inyeccion de medio de contraste, que permite clasificar correctamente las lesiones renales y optar por la mejor estrategia de atencion medica inicial. Ante un traumatismo penetrante, el primer paso consiste en valorar el estado hemodinamico del paciente. En el caso de una inestabilidad hemodinamica, se debe hacer una exploracion quirurgica de inmediato. Si, en cambio, el paciente se encuentra estable, hay que practicar una TC con adquisicion de imagenes tardias. Las lesiones renales de grados I y II justifican la abstencion terapeutica. Las lesiones de grados III y IV, asociadas a otras lesiones intraperitoneales que requieren una laparotomia de urgencia, se exploran de forma quirurgica y pueden ser reconstruidas o sufrir una nefrectomia. La mayoria de las lesiones de grado IV con dano del hilio renal, y de las lesiones de grado V, tambien requieren tratamiento quirurgico. Las lesiones renales menores justifican la abstencion terapeutica y el control mediante determinaciones sucesivas de la concentracion de hemoglobina y del hematocrito, asi como exploraciones con TC o ecografia para seguir la evolucion de la lesion y detectar posibles urinomas o hemorragias prolongadas. La disminucion progresiva del hematocrito y las fistulas arteriovenosas se deben tratar al principio mediante embolizacion. Si fuera necesario, Las fistulas urinarias persistentes en caso de abstencion terapeutica deben tratarse por cateterismo ureteral y drenaje percutaneo del urinoma.