[Mitomycin C for the treatment of superficial tumors of the bladder (Tis-Ta-T1) with one or more risk factors. Argentinian Cooperative Group of Oncourology (GCAO)]. / Mitomicina-C para el tratamiento de los tumores superficiales de vejiga (Tis-Ta-T1) con uno o más factores de riesgo. Grupo Cooperativo Argentino de Oncourología (GCAO).

OBJECTIVES: To determine the efficacy and toxicity of intravesical mitomycin C in superficial bladder tumors (Tis Ta T1) completely resected with one or more risk factors. (Protocol U. 01/90). METHODS: The patients received six instillations weekly of 40 mg mitomycin C within 15 days post-TUR of a superficial bladder tumor with one or more risk factors: histological grade 3, tumor size more than 3 cm and/or multicentric lesion. The patients were evaluated by cystoscopy every three months for the first two years and every six months thereafter. Toxicity was evaluated according to Miller's score. Tumor recurrence, disease-free interval and survival were analyzed. RESULTS: 126 patients were entered into the study; of these, 110 were evaluable. At 18 months mean follow-up (range 6-36 months), 77 patients (70%) remain disease-free; the mean time to recurrence was 13.8 months. There were no differences between patients with one, two or three risk factors or those who received or did not receive previous treatments. The patients tolerated the treatment well; there were no dropouts or systemic toxicity. CONCLUSIONS: 1. At 18 months mean follow-up, 77 of 110 patients (70%) remain disease-free; 2. The mean time to recurrence was 13.8 months; 3. Local toxicity was minimal; 4. There were no dropouts due to toxicity; 5. Systemic toxicity was not observed.

Mechanisms of pulsus paradoxus in airway obstruction.

To assess the mechanisms of pulsus paradoxus (i.e., inspiratory decline of greater than or equal to 10 Torr in systolic pressure) in airway obstruction, we studied 12 patients with chronic airflow obstruction before and during breathing through an external resistance that provided loads during both inspiration and expiration. Esophageal pressure (Ppl) and brachial artery pressure, relative to either atmospheric (Pa) or esophageal pressure (Patm), were measured simultaneously during normal and loaded breathing. It was assumed that changes in intrathoracic systemic arterial transmural pressure were adequately represented by Patm. During control, no significant difference between systolic fluctuation (delta Pa) and pleural swings (delta Ppl) was found. Concurrently, inspiratory and expiratory Patm were nearly identical. By contrast, under maximally loaded conditions, higher magnitudes of delta Ppl than delta Pa were found and consequently Patm rose with inspiration. In this connection, the plot of delta Pa against delta Ppl showed that the slopes for delta Ppl less than or equal to 15 Torr (1.2 Torr delta Pa/delta Ppl) and delta Ppl greater than 15 Torr (0.4 Torr delta Pa/delta Ppl) were significantly different. Under all experimental conditions we found during inspiration a rise in diastolic Patm that is consistent with an increase in left ventricular afterload.(ABSTRACT TRUNCATED AT 250 WORDS)