Indications and Contraindications
Renal cystic disease is common, with an increasing prevalence likely related to the use of cross-sectional imaging over the last several decades. Renal cysts have been identified in up to one third or more of patients 50 years of age and older. The majority of these cysts are asymptomatic and only incidentally identified during evaluation for alternative indications. The Bosniak classification is used to classify renal cysts based on features more suspicious for malignancy, such as enhancement, septation, calcification, and solid elements ( Table 21-1 ). For asymptomatic simple cysts (Bosniak class I or II), no further evaluation or treatment is necessary. Cysts classified as Bosniak class IIF require ongoing monitoring. Patients with class III or IV cysts should be counseled toward surgery with radical, or ideally partial, nephrectomy because of the higher rate of malignancy ( Fig. 21-1 ). Further discussion regarding management of class III and IV renal cysts is therefore beyond the scope of this chapter.
Type | Radiologic Findings | Computed Tomography Attenuation and Enhancement | Management |
---|---|---|---|
I | No septa, calcification, or solid components | Water attenuation No enhancement | No follow-up |
II | Thin hairline septa, fine septal or wall calcifications Possible minimal enhancement of thin septae or wall Hyperdense cyst <3 cm | Water or high attenuation No enhancement | No follow-up |
IIF | Increased septae Mild thickening and enhancement of the septae Possible thick nodular calcifications Hyderdense cyst >3 cm | Variable attenuation No or little enhancement | Imaging follow-up |
III | Thickened irregular walls or septa with possible enhancement | Variable attenuation Contrast enhancement | Surgery |
IV | Solid enhancing component | Variable attenuation Contrast enhancement | Surgery |
Symptomatic simple renal cysts can significantly affect a patient’s quality of life. Displacement of adjacent renal tissue or spontaneous bleeding into the cyst can result in continuous or intermittent pain episodes, and compression of the collecting system can cause intermittent upper tract obstruction. In addition, fluid within the cyst can become infected, acting as a nidus for recurrent urinary tract infections. Surgical intervention with laparoscopic decortication can be considered in those patients with symptomatic renal cysts, in the absence of imaging findings suspicious for malignancy. Other treatment modalities including percutaneous cyst aspiration with injection of a sclerotic agent can also be considered, although success rates are lower compared with laparoscopic cyst decortication. Notably, patients with symptomatic renal cysts in the setting of polycystic kidney disease are often excellent candidates for decortication. Contraindications include inability to tolerate general anesthesia, untreated infection, history of extensive abdominal or retroperitoneal surgery, and uncorrected bleeding diathesis.
Patient Preoperative Evaluation and Preparation
Before laparoscopic cyst decortication, patients should undergo a full history and physical examination. Important elements in the history include symptom severity and timing, family history of renal cystic disease or malignancy, current medications, and medical comorbidities. Prior abdominal and urologic procedures should be documented. Physical examination including cardiovascular system, pulmonary system, abdominal or flank area, and genitourinary system should be performed to assess for additional comorbidities. Preoperative laboratory evaluation should include an electrolyte panel, blood urea nitrogen (BUN), creatinine, complete blood count, urinalysis, and urine culture. Ideally, patients should undergo computed tomography (CT) of the abdomen and pelvis with nephrographic and delayed phases to carefully evaluate the renal parenchyma and cystic structures for findings suggestive of malignancy. In patients with medical renal disease or contrast allergies, in whom iodinated contrast is contraindicated, alternative imaging with renal ultrasound or magnetic resonance imaging (MRI) should be considered. After determination of the appropriate candidacy for laparoscopic cyst decortication, a careful discussion regarding patient expectations is important during the informed consent. Patients must understand that, despite appropriate surgical intervention, symptoms may persist.
Operating Room Configuration and Patient Positioning
Surgical approach (retroperitoneal versus transabdominal) dictates patient positioning. The transabdominal approach is most commonly performed. The retroperitoneal approach can be especially useful for cystic lesions in the posterior aspect of the kidney, although these lesions can often be exposed transabdominally with additional renal mobilization.
Patients should receive appropriate perioperative antimicrobial therapy, and this should be discontinued within 24 hours of the procedure in the absence of extenuating circumstances. Routine urinary and gastrointestinal decompression is warranted with placement of an indwelling Foley catheter and orogastric tube (this is removed at the cessation of the procedure, before extubation). If the cyst appears to be in close proximity to the collecting system, a ureteral catheter can be placed to assist with intraoperative collecting system evaluation. This can be converted to an indwelling ureteral stent if necessary. If there is no concern for collecting system injury, the ureteral catheter and indwelling urinary catheter can be removed before hospital discharge. It is also important to ensure that sequential compression devices are in place (unless contraindicated) to prevent lower extremity deep vein thrombosis.
Patient positioning is dictated by approach, with 45-degree flank position for the transabdominal approach ( Fig. 21-2 ) and full flank position for the retroperitoneal approach ( Fig. 21-3 ). An axillary roll is routinely placed to prevent neuromuscular injury. The kidney rest is used with the retroperitoneal approach. With the transabdominal approach, the surgeon and assistant stand on the side contralateral to the lesion ( Fig. 21-4, A ). During the retroperitoneal approach, the surgeon stands posterior to the patient ( Fig. 21-4, B ).