Renal Decompression for Malignant Ureteric Obstruction Yields Modest Survival Gains Amid High Complication Burden

A retrospective cohort study conducted at Lyell McEwin Hospital in Adelaide evaluated clinical outcomes following renal decompression for malignant ureteric obstruction (MUO). The findings describe survival rates, renal function changes, complication frequency, and prognostic factors among patients treated between 2018 and 2023.

The study included 84 patients who underwent either retrograde ureteric stent placement or percutaneous nephrostomy. Median overall survival following intervention was 197 days. At the end of the study period, 79% of patients had died. Emergency decompression was performed in 75% of cases.

Colorectal (27%), bladder (15%), and cervical (14%) cancers were the most frequent underlying malignancies. The obstruction most often involved the distal ureter and was typically caused by direct extrinsic compression. Bilateral obstruction was observed in 46% of patients.

Renal function improved in 78% of patients at 12 months post-treatment compared to pre-intervention values. However, 84% of patients had reduced renal function at 12 months when compared to their baseline (pre-morbid) levels.

Complications were common. A total of 143 stent-related complications were reported, with 51% of patients requiring hospitalization for issues such as urinary tract infection (47%), occluded stents, and stent-related pain. These complications accounted for 966 cumulative inpatient days. Additionally, 44 unplanned stent exchanges occurred during follow-up.

The study applied the PLaCT prognostic score, which incorporates primary cancer site, laterality of obstruction, serum creatinine, and treatment status. Patients were stratified into good, intermediate, and poor prognosis groups with median survivals of 555, 235, and 67 days, respectively. However, the PLaCT score did not independently predict survival after adjusting for other variables in multivariate analysis.

In adjusted models, only two factors remained significantly associated with longer survival: male sex and having further cancer treatment planned after decompression. Female sex was associated with shorter survival, although the study did not identify a specific underlying cause. Gynaecologic malignancy was not a statistically significant predictor.

The authors report that the decision to perform renal decompression for MUO involves consideration of potential renal recovery, the likelihood of further oncologic treatment, and the risk of complications. The study did not include a control group and did not assess quality of life outcomes. The authors recommend further prospective research to clarify the benefits and risks of decompression and to evaluate prognostic scoring systems in broader clinical settings.