[Internal drainage in cancer patients: optimizing treatment of stent-related symptoms]

The so-called stent-related symptoms caused mainly by detrusor overactivity due to distal ("cystic") curl of the internal stent are common among patients with this type of drainage. The need for long-term stenting makes the quality of life of cancer patients one of the challenging problems of modern urology. The aim of this study was to optimize treatment of stent-related symptoms in cancer patients with internal long-term stents by complementing the treatment regimen with m-anticholinergic solifenacin.

From November 2013 to November 2015 68 cancer patients (26 males, 42 females, age 36-79 years) underwent elective internal ureteral stenting for drainage of the upper urinary tract (UUT) with special long-term stents coated with the hydrogel. The urinary tract obstruction was caused by urological (24), gynecological (26) and colorectal (18) cancers. Before deciding on urinary tract drainage, all patients were treated with radiation or chemotherapy, 28 (41.2%) patients underwent surgery, but on admission all of them had contraindications to radical surgery for different reasons. In 52 (76.5%) patients UUT stenting was performed using transurethral access, in 12 (17.6%) by percutaneous access and in another 4 (5.9%) by the combined access with patients in the supine position. Percutaneous and combined access was used in cases of impracticability (failure) of transurethral stenting. Patients in group 1 (n=32) after stent placement received standard therapy co-administered with solifenacin 5 mg daily, group 2 (n=36) - only standard therapy. The data analyzed were the technical features of the internal drainage, optimal access and registered solifenacin-related adverse events. Control examinations were scheduled once in 3 months after stent placement according to the following algorithm: ultrasound scanning, laboratory test monitoring and, if indicated, plain urography. To objectify the severity of stent-related symptoms, a survey of patients using a special questionnaire was conducted. Visual analog scale was used to measure subjectively the patients condition.

After 12 months only 48 patients (26 from group 1 and 22 from group 2) completed the study. Follow-up examinations revealed that the patients in group 1 had significantly lower score of stent-related symptom severity and better ratings in visual analog scale. The greatest difference (1-2 points) was found in urgency and urinary frequency scores. The safety profile of solifenacin 5 mg corresponded to the findings of previous studies, there was no serious adverse events requiring discontinuation of the drug.

Installing internal stents in UUT in cancer patients requires relevant experience in Roentgen-endoscopic operations using transurethral and percutaneous approaches and special equipment. In most cases, for preventing and eliminating supravesical obstruction in cancer patients, special internal stents for the long term placement are required. The add-on solifenacin therapy 5 mg/day resulted in almost 20% reduction in the severity of stent-related irritative symptoms and improved the quality of life in this extremely challenging category of patients.