Primo N. Lara Jr., Eric Jonasch (Eds). Kidney Cancer. Principles and Practice. Springer-Verlag (2012)
The incidence of renal cell carcinoma (RCC) continues to increase to rise due to the widespread use of crosssectional imaging with the greatest absolute increase noted in renal tumors sized 2–4 cm. In 2010, there was an estimated 58,240 new cases of renal tumors accounting for 4% and 3% of new cancer cases in men and women, respectively. Survival for stage I and II RCC – T1 or T2 tumors without evidence of nodal or metastatic disease – has been reported at 96% and 82%. These favorable survival rates are consistent with the recently released AUA guidelines regarding the management and outcomes of the clinical T1 renal mass, which demonstrate that recurrence-free survival ranged from 87.0% for ablative therapy to 99.2% for surgical treatment of T1 renal masses. Most new cases of localized RCC present incidentally as an enhancing renal mass. Historical series demonstrate that 77–83.9% of these lesions represent a malignant tumor of the kidney with clear cell carcinomas the most common histologic subtype.
According to the most recent National Cancer Comprehensive Network (NCCN) Guidelines, evaluation of a newly diagnosed renal mass consists of a complete history and physical examination, urinalysis, complete blood count, comprehensive metabolic panel including serum creatinine, contrast-based abdominal cross-sectional imaging if the mass was discovered on an ultrasound, chest x-ray or CT scan of the chest, and bone scan/brain MRI/further metastatic workup as clinically indicated. Although not explicitly stated in the NCCN Guidelines, an estimation of the patient’s glomerular filtration rate should be performed whereas serum creatinine is a poor indicator of renal function, and many patients who present with an enhancing renal mass have underlying chronic kidney disease (CKD) that is not underrecognized using serum creatinine alone. Furthermore, in a patient with a history of urothelial cell carcinoma (UCC) of the bladder and/ or upper urinary tract or if the renal mass is central and UCC is suspected, the use of selective urinary cytology and endoscopic evaluation of the lower urinary tract and the affected upper urinary tract should be employed to exclude a diagnosis of urothelial tumor of the renal pelvis. Although the predictive value of renal mass biopsy has improved greatly, its routine use is not recommended unless the patient is considering active surveillance (AS) or a form of ablative therapy – cryosurgery or radiofrequency ablation (RFA).
Once the evaluation of an enhancing renal mass has been completed, the urologic surgeon then needs to consider the risks of intervention against the biology of the disease and the patient’s competing health risks. Although localized RCC is eminently curable by excision, surgery carries the risk of procedure-related complications as well as patient comorbidity-related complications. Since localized RCC has such excellent short and intermediate survival rates when treated and grows yearly at predictable rates when observed, one does not want to compromise the patient’s quality/duration of life due to treatment-induced complications when treatment may not effect a patient’s overall survival.