What's the next step for a patient with a 3 cm mid ureteric mass and lytic bone lesion on iliac crest?

Management of 3 cm Mid-Ureteric Mass with Lytic Iliac Crest Lesion

The immediate next step is ureteroscopic biopsy to establish tissue diagnosis before proceeding to definitive treatment, as the presence of a lytic bone lesion raises concern for metastatic disease that would fundamentally alter management from curative nephroureterectomy to palliative systemic therapy. 1, 2

Diagnostic Workup Priority

Tissue Diagnosis is Essential First

• Ureteroscopic biopsy must be performed before any definitive surgical decision to confirm urothelial carcinoma versus other histologies (adenocarcinoma, squamous cell, small cell carcinoma) that would require different treatment approaches 1, 3

• Ureteroscopic biopsy provides 94% diagnostic accuracy for malignancy and 78% accuracy for tumor grade prediction, making it highly reliable for treatment planning 3, 4

• A multi-biopsy technique using 3Fr cup forceps should be employed to maximize diagnostic yield and obtain lamina propria in approximately 62% of cases, which helps assess invasion depth 4

• The 3 cm size and mid-ureteral location are accessible to ureteroscopy with high diagnostic success rates 2, 3

Staging Workup Must Be Completed

• CT urogram (already performed with contrast) should be reviewed specifically for upper tract disease extent, lymphadenopathy, and other organ involvement 1

• Chest imaging (CT chest preferred over plain radiograph) is mandatory to evaluate for pulmonary metastases given the concerning lytic bone lesion 1

• The lytic iliac crest lesion requires immediate characterization - this could represent metastatic urothelial carcinoma (rare but reported), multiple myeloma, or other primary bone pathology 5, 6

• PET/CT scan should be performed to assess metabolic activity of both the ureteric mass and the lytic bone lesion, as PET/CT is superior for detecting metabolically active lytic lesions 5

• Bone biopsy of the iliac crest lesion may be necessary if PET/CT shows uptake, as this would confirm metastatic disease and completely change management from surgical to systemic therapy 5, 6

Critical Decision Point: Metastatic vs Localized Disease

If Bone Lesion is Metastatic Disease

• Nephroureterectomy is NOT indicated if the lytic lesion represents metastatic urothelial carcinoma, as this would be stage IV disease requiring systemic platinum-based chemotherapy 7, 1

• The rare case reports of urothelial carcinoma metastasizing to distal bones (including calcaneus) demonstrate that multimodality therapy with chemotherapy, radiation, and bisphosphonates provides palliation but not cure 6

• Ureteroscopic biopsy histology becomes crucial to guide chemotherapy selection, as pure adenocarcinoma or squamous histology responds poorly to standard urothelial regimens 7

If Bone Lesion is Unrelated (e.g., Multiple Myeloma)

• The lytic bone lesion pattern is classic for multiple myeloma rather than urothelial metastases 7, 5

• Serum protein electrophoresis, urine protein electrophoresis, serum free light chains, and bone marrow biopsy would be needed to evaluate for plasma cell dyscrasia 7

• If confirmed as separate pathology, proceed with urothelial carcinoma treatment based on ureteroscopic biopsy results 1, 2

Definitive Treatment Algorithm (After Tissue Diagnosis)

For Localized High-Grade Disease (No Metastases)

• Nephroureterectomy with bladder cuff excision and regional lymphadenectomy is the standard treatment for high-grade upper tract urothelial tumors 1, 2

• The 3 cm size and mid-ureteral location make this amenable to complete surgical resection 2

• Regional lymphadenectomy is mandatory for high-grade tumors to provide accurate staging and potential therapeutic benefit 1

For Localized Low-Grade Disease (If Biopsy Shows This)

• Kidney-sparing surgery with segmental ureterectomy and end-to-end anastomosis is preferred for low-grade tumors, as survival outcomes match nephroureterectomy while preserving renal function 2

• However, the 3 cm size raises concern for higher grade/stage disease, making low-grade histology less likely 2

• Ureteroscopic laser ablation could be considered for low-grade disease but has 25-85% local recurrence rates versus 0-18% for segmental resection 2

Common Pitfalls to Avoid

• Do NOT proceed directly to nephroureterectomy without tissue diagnosis - the lytic bone lesion could indicate metastatic disease where surgery provides no survival benefit 1, 6

• Do NOT assume the bone lesion is metastatic without biopsy or advanced imaging - multiple myeloma is far more common than bone metastases from urothelial carcinoma 7, 5

• Do NOT rely on ureteroscopic biopsy for accurate staging - while 78% accurate for grade, it understages disease in 45% of cases where lamina propria invasion is present 4

• Do NOT perform segmental ureterectomy for mid-ureteral tumors without considering higher failure rates compared to distal ureteral locations 2

• Inadequate ureteroscopic biopsy tissue occurs in 25% of cases due to crush artifact and limited size - if initial biopsy is non-diagnostic, repeat with multi-biopsy technique 8, 4

Immediate Action Plan

1. Perform ureteroscopic biopsy with multi-biopsy technique (3-5 samples including cup forceps and resection loop if possible) 3, 4

2. Order PET/CT scan to characterize both ureteric mass and lytic bone lesion metabolic activity 5

3. Obtain CT chest to complete metastatic workup 1

4. Check serum protein electrophoresis, free light chains, and complete metabolic panel to evaluate for plasma cell dyscrasia 7

5. Consider bone biopsy of iliac crest lesion if PET/CT shows uptake and myeloma workup is negative 5, 6

6. Multidisciplinary tumor board discussion after all diagnostic information is available to determine curative versus palliative intent 6