Chandrasekar T, et al. - This trial discerned the intervention rates, progression and cancer-specific survival outcomes of patients with complex renal cysts. Very high cancer-specific survival and overall survival were reported for patients with Bosniak IIF-IV renal cysts, with only one cancer-specific death. No cancer deaths recorded in those that did not undergo intervention. Reconsideration was necessitated of the management guidelines for complex renal cysts, especially for initial surveillance in Bosniak III cysts.

Methods

• Data was extracted from a radiology data-mining system (Montage; Montage Healthcare Systems, Philadelphia, PA, USA).
• All reported cases of “complex renal cyst” in the institution were identified (2001-2013).
• Primary end points included overall (OS) and cancer specific survival (CSS).
• Radiographic progression and upgrading, clinical progression, and final histology on surgical pathology were the secondary endpoints.

Results

• 336 patients with a “complex renal cyst” enrolled, of which 185 (55.1%), 122 (36.3%), and 29 (8.6%) had Bosniak IIF, III and IV cysts, respectively.
• Median follow-up was 67.1 (34.4-101.6) months.
• 1 cancer-specific death (0.3%) was reported and overall mortality was 6.2%, among the 332 patients with follow-up.
• Ten (5.4%), 37 (30.3%) and 18 (62.1%) of the Bosniak IIF, III and IV patients underwent either surgical or ablative intervention, respectively.
• Indication for intervention was predominantly age (intervention 50.1±15.9, no intervention 62.5±13.9) and complexity.
• Surgery with radical (23 [35%]) or partial nephrectomy (37 [57%]) appeared to be most common, and favorable final pathology was determined.
• Two treated patients presented with recurrence during follow-up.
• The cancer specific survival was found to be 100%, when excluding VHL patients.