Prognostic factors in malignant ureteric obstruction

Abstract

Objective: To validate a model to stratify patients with obstructive nephropathy due to malignant ureteric obstruction, associated with a poor prognosis, into different prognostic groups, as a recent report identified low serum albumin, degree of hydronephrosis and number of events related to metastatic disease as prognostic indicators before palliative decompression.

Patients and methods: We retrospectively review the charts to identify all patients who had a nephrostomy tube inserted for malignant ureteric obstruction. Laboratory and clinical factors that might influence prognosis were reviewed to attempt to externally validate the previously identified factors and model for risk stratification.

Results: The median (range) age of the 49 patients identified was 71 (36-91) years, and the median survival was 174 (14-602) days. Tumours were of urological origin in 66% of patients. Patients with prostate cancer had nephrostomy tubes indwelling for a mean of 279 days, vs 190 days (P = 0.07) for patients with tumours not of prostatic origin. A serum albumin level of >30 g/L (P ≤ 0.001), serum sodium <135 mmol/L (P = 0.019) and three or more events related to dissemination of cancer (P = 0.04) were factors associated with a significantly shorter mean survival. Complications related to the nephrostomy tube were experienced by 39% of patients. The model proved useful in stratifying these patients into different risk groups (P = 0.002).

Conclusion: Consistent with a previous report we showed that a low serum albumin level and events related to metastatic disease were indicative of a poor prognosis. We also found that a low serum sodium level might be associated with a worse prognosis. We externally validated a model for stratifying patients into different prognostic groups. Palliative decompression is associated with significant morbidity.