What is the best course of action for an elderly male patient with end-stage kidney disease (ESKD) on dialysis, recently diagnosed with bilateral exophytic masses on the kidneys and bilateral hydronephrosis?

Management of Bilateral Renal Masses in ESRD Patient on Dialysis

Immediate Recommendation

For an elderly male with ESRD on dialysis presenting with bilateral exophytic renal masses and hydronephrosis, obtain renal mass biopsy (RMB) for tissue diagnosis first, then pursue active surveillance rather than surgical intervention, given that dialysis dependence eliminates the primary rationale for nephron-sparing surgery and the patient's competing mortality risks outweigh oncologic benefits. 1

Diagnostic Workup

Initial Imaging and Laboratory Assessment

• High-quality multiphase cross-sectional abdominal imaging should already be available from the CT that identified the masses 1
• Obtain comprehensive metabolic panel (CMP), complete blood count (CBC), and urinalysis 1
• Chest imaging is mandatory to evaluate for thoracic metastases if malignancy is suspected 1
• For bilateral hydronephrosis evaluation, CT urography (CTU) without and with IV contrast provides the most comprehensive morphological and functional information about the genitourinary tract 1

Renal Mass Biopsy Strategy

Multiple core biopsies (at least 2-3 cores with 16-18 gauge needle) are strongly preferred over fine needle aspiration in ESRD patients to optimize diagnostic yield 1

• RMB can be performed under CT or ultrasound guidance 1
• The sensitivity is 97.5% and specificity 96.2% when malignancy is diagnosed, with positive predictive value of 99.8% 1
• Non-diagnostic rate is approximately 14%, which can be substantially reduced with repeat biopsy 1
• Histologic determination of RCC subtype is highly accurate when tissue is obtained 1

Treatment Decision Algorithm

Why Surgery is NOT Recommended in This Case

The traditional indications for nephron-sparing surgery are irrelevant in dialysis-dependent ESRD patients:

• Nephron-sparing approaches are prioritized for patients with anatomic or functionally solitary kidney, bilateral tumors, or preexisting CKD specifically to avoid dialysis or preserve remaining renal function 1
• This patient is already dialysis-dependent, eliminating the primary rationale for partial nephrectomy 1
• Radical nephrectomy would render the patient anephric with no functional consequence since he already requires dialysis 1
• However, surgery in elderly ESRD patients carries substantial perioperative morbidity and mortality that likely exceeds oncologic benefit 1

Active Surveillance as Primary Strategy

Active surveillance should be prioritized when anticipated risks of intervention or competing risks of death outweigh potential oncologic benefits 1

• For elderly patients with extensive comorbidities (ESRD qualifies), active surveillance is explicitly recommended as a primary consideration 1
• Many small renal masses have low oncologic potential and indolent behavior 1
• Repeat imaging in 3-6 months to assess interval growth is the appropriate initial step 1
• Short- and intermediate-term oncologic outcomes indicate that monitoring small renal masses initially, then treating for progression if required, is an appropriate strategy 1

When to Consider Intervention

Active treatment should only be recommended if:

1. Biopsy confirms high-grade malignancy with aggressive features 1
2. Masses demonstrate rapid growth on surveillance imaging 1
3. Patient develops symptoms attributable to the masses 1
4. The patient has good performance status and life expectancy exceeding 5-10 years (unlikely in elderly ESRD) 1

Management of Bilateral Hydronephrosis

Etiology Assessment

• Bilateral hydronephrosis in the setting of bilateral renal masses suggests either direct ureteral involvement by tumor or extrinsic compression 1
• Less likely etiologies include bladder outlet obstruction (evaluate prostate size) or retroperitoneal fibrosis 1

Intervention Threshold

Ureteral stenting is indicated only if:

• Extension of masses to renal sinus or involvement of middle-to-distal ureters causes symptomatic hydronephrosis 1
• Patient develops recurrent urinary tract infections 1
• Asymptomatic hydronephrosis in dialysis-dependent patients does NOT require intervention since renal function preservation is not relevant 1

Alternative Considerations if Intervention Required

Thermal Ablation

If intervention becomes necessary, thermal ablation is preferred over surgery for masses <3 cm 1

• Percutaneous approach is preferred 1
• Both radiofrequency ablation and cryoablation are options 1
• RMB should be performed prior to thermal ablation 1
• Counsel about increased likelihood of tumor persistence/recurrence (10-15% vs 1-2% for surgery), which may require repeat ablation 1

Surgical Options (Last Resort)

If surgery is absolutely necessary despite dialysis dependence:

• Bilateral radical nephrectomy would be the only oncologically sound option given bilateral disease 1
• This renders the patient anephric, which has no functional consequence in dialysis patients 1
• However, surgical mortality may reach 10% in complex cases, particularly in elderly patients with comorbidities 1

Critical Pitfalls to Avoid

1. Do not pursue nephron-sparing surgery in dialysis-dependent patients - the rationale for preserving renal function is eliminated 1

2. Do not base treatment decisions solely on tumor size or imaging characteristics - consider the patient's overall life expectancy, comorbidities, and competing mortality risks 1, 2

3. Do not intervene on asymptomatic bilateral hydronephrosis in dialysis patients - there is no renal function to preserve 1

4. Do not delay biopsy if considering any intervention - tissue diagnosis is essential for risk stratification and treatment planning 1

5. Recognize that many elderly ESRD patients have limited life expectancy from cardiovascular disease and other comorbidities that exceed oncologic risk from small renal masses 2, 3, 4

Ongoing Management Within ESKD Life-Plan

• This clinical scenario should be integrated into the patient's individualized ESKD Life-Plan with quarterly reviews of clinical status 1, 5
• Consider palliative care consultation to address goals of care and symptom management 2, 5
• If the patient is a potential transplant candidate, referral for renal transplant evaluation should be considered, as transplantation offers superior outcomes to dialysis 1, 5
• Maintain focus on quality of life and symptom burden rather than aggressive oncologic intervention 2, 5