What management is recommended for a 71-year-old male with a large 8.6 cm right renal cyst and a 1.8 cm left renal cyst, in the context of a history of high-grade bladder Transitional Cell Carcinoma (TCC) and current symptoms of nocturia and occasional slow stream urine?

From the Guidelines

The large renal cysts, particularly the 8.6 cm right renal cyst, should be monitored with follow-up imaging, as recommended by recent guidelines 1. For asymptomatic simple renal cysts of this size, surveillance with repeat ultrasound in 6-12 months is appropriate to assess for any changes in size or characteristics. If the patient develops symptoms specifically attributable to the cyst (persistent flank pain, hematuria, or signs of obstruction), or if future imaging shows concerning features (internal septations, solid components, or irregular walls), then intervention would be warranted. Intervention options would include percutaneous aspiration with or without sclerotherapy or surgical excision depending on cyst characteristics. The current occasional right flank pain is likely musculoskeletal as noted, but should be reassessed if it worsens or becomes persistent. Some key points to consider in the management of renal cysts include:

• The use of CTU without and with IV contrast for pretreatment staging of urothelial cancer, as it is the most accurate and preferred modality for diagnosis and staging, both local and distant 1.
• The importance of evaluating for synchronous UTUC or bladder UC, as approximately two-thirds of UTUCs present as high-grade invasive disease at the time of diagnosis, and multifocal disease has been reported in approximately 25% to 30% of UTUC 1.
• The role of CTU in detecting UCs, with a pooled sensitivity of 96% (95% CI, 88%-100%) and a specificity of 99% (95% CI, 98%-100%) for identifying UC 1. Simple renal cysts are common in older adults and most remain asymptomatic, requiring only periodic monitoring rather than immediate intervention. The patient's bladder cancer surveillance remains the primary concern, and the upcoming cystoscopy should proceed as scheduled. Key aspects of the patient's condition to monitor include:
• The size and characteristics of the renal cysts
• The presence of symptoms such as flank pain, hematuria, or signs of obstruction
• The results of future imaging studies to assess for any changes in the cysts
• The patient's overall health and any changes in their condition that may affect the management of the renal cysts.

From the Research

Renal Cysts Management

• The patient has a large renal cyst (8.6 cm) and a smaller one (1.8 cm) with no evidence of obstruction or renal calculi 2.
• Simple renal cysts are generally benign, asymptomatic, and discovered incidentally, but they can enlarge, become symptomatic, and develop complications over time, requiring intervention 2, 3.
• The Bosniak classification system is used to characterize renal cysts, and most simple cysts are classified as Bosniak I or II, which are typically benign 4, 5.
• The management of simple renal cysts depends on their size, symptoms, and complications, as well as the patient's overall health and preferences 3.
• Treatment options for simple renal cysts include watchful waiting, aspiration, sclerotherapy, and laparoscopic surgery, with ethanol percutaneous sclerotherapy and laparoscopy being the most commonly reported treatment modalities 3.

Treatment Considerations

• The patient's age and overall health should be taken into account when considering treatment options for the renal cysts 2, 5.
• The presence of symptoms, such as flank pain, and the size of the cysts should also be considered when deciding on a treatment plan 2, 3.
• Regular follow-up and surveillance may be necessary to monitor the size and characteristics of the cysts and to detect any potential complications early on 5, 6.

Diagnostic Evaluation

• Imaging studies, such as ultrasound and CT scans, are essential for diagnosing and evaluating renal cysts 4, 6.
• The Bosniak classification system can help guide the diagnostic evaluation and management of renal cysts 4, 5.
• Biopsy and other diagnostic tests may be necessary to rule out malignant or neoplastic processes, especially in complex renal cysts 4, 5.