Management of Cytology Showing Scattered Squamous and Urothelial Cells with Degenerative Changes
The next step for a patient with cytology showing scattered squamous and urothelial cells with degenerative changes should be a complete urologic evaluation including cystoscopy to rule out bladder cancer.
Understanding the Significance of These Cytology Findings
Degenerative changes in urothelial and squamous cells on cytology represent a non-specific finding that requires further investigation. While these changes alone are not diagnostic of malignancy, they cannot be dismissed as benign without additional workup, especially given that:
- Urothelial carcinoma is the most common histologic subtype in the urinary tract (>90% of urinary tract tumors) 1
- Squamous cells may represent normal contamination from the lower urinary tract or vagina in women, but could also indicate squamous differentiation in urothelial carcinoma 1
- Degenerative changes can sometimes mask underlying cellular atypia that may be associated with malignancy
Recommended Diagnostic Algorithm
1. Initial Evaluation
- Office cystoscopy to directly visualize the bladder mucosa for any suspicious lesions 1
- Complete upper tract imaging (one of the following):
- CT urography (preferred approach) 1
- Intravenous pyelogram (IVP)
- Retrograde pyelogram
- Renal ultrasound with retrograde pyelogram
- MRI urogram
2. If Cystoscopy Shows a Lesion
- Schedule transurethral resection of bladder tumor (TURBT) with bimanual examination under anesthesia 1
- If the lesion appears solid (sessile), high-grade, or suggests muscle invasion, obtain CT scan of abdomen and pelvis before TURBT 1
- TURBT should include adequate sampling of muscle within the area of the tumor to assess for invasion 1
3. If Cystoscopy is Normal but Cytology Remains Concerning
- Consider selected mapping biopsies of the bladder 1
- Evaluate upper tract with cytology and consider ureteroscopy 1
- Consider TUR biopsy of the prostate in men 1
4. If All Evaluations Are Negative
- Follow-up with repeat cytology and cystoscopy in 3 months 1
Important Considerations
Potential Pitfalls
Misinterpreting degenerative changes as benign: Degenerative changes can sometimes mask underlying cellular atypia that may be associated with malignancy 2, 3
Overlooking squamous cells: The presence of dysplastic squamous cells in urine cytology may indicate high-grade urothelial carcinoma with squamous differentiation, which occurs mainly in high-grade urothelial carcinoma with invasion 4
Ignoring upper tract sources: Remember that urothelial tumors can originate in the renal pelvis (8%) and ureter/urethra (2%) 1
Special Populations
Women: Consider gynecologic sources of squamous cells, as atypical squamous cells in urine may rarely originate from gynecologic malignancies 5, 6
Patients with hematuria: Microscopic hematuria is the most common presenting symptom of bladder cancer and should increase suspicion for malignancy even with equivocal cytology 1
By following this systematic approach to evaluating patients with degenerative changes in urothelial and squamous cells, you can ensure appropriate diagnosis and management while minimizing the risk of missing significant pathology.