Does the Simple Renal Cyst Treatment Improve Renal Function: A Pilot Study

Background: The current study aims to assess the effects of the large simple renal cyst (SRC) surgery on renal function for the first time. Materials and Methods: This case‐series study included 22 patients with larger than 50 mm single SRC who underwent laparoscopic cyst unroofing surgery. Twenty‐four‐hour urinary protein, creatinine, and volume along with plasma creatinine and estimated glomerular filtration rate (GFR) were measured in patients before and 1 month after surgery. Patients underwent abdominopelvic computed tomography‐scan without contrast and parenchymal thickness diameter adjacent to the cyst was measured before and after surgery. Results: Mean age and weight of patients were 52.2 ± 8.9 years and 77 ± 10.9 akg, respectively. There was no significant difference between plasma creatinine and GFR before and after surgery (P = 0.25 and 0.37, respectively). Twenty‐four‐hour urinary volume, creatinine, and protein before and after surgery revealed no significant changes (P = 0.37, 0.08, and 0.31, respectively). The mean improvement of parenchymal thickness diameter after surgery was 10.4 ± 0.7 mm which was statistically significant (P = 0.001). However, it was not correlated with the mean estimated GFR change (r = 0.349, P = 0.13). Conclusions: Although laparoscopic unroofing of renal cyst recovered renal parenchymal thickness noticeably, it did not improve renal function significantly; therefore, the latter factor lonely should not be considered a reason for surgery decision. Observation can be chosen as a safe treatment strategy in large SRCs without concern about renal function.