Abstract
BACKGROUND: Squamous cell carcinoma (SCC) of the ureter is a rare and aggressive malignancy, accounting for 1-1.6% of upper tract urothelial carcinomas. Chronic irritation from long-standing stones, hydronephrosis, or infection can lead to squamous metaplasia and malignant transformation. SCC is often diagnosed late, contributing to a poor prognosis. CASE PRESENTATION: A 57-year-old male, past smoker and farmer by occupation, presented with weakness, weight loss, and dysuria. Urinalysis revealed pyuria and microscopic hematuria. Contrast-enhanced CT demonstrated a duplex left kidney with gross hydronephrosis of the upper moiety, multiple ureteric and bladder calculi, and a distal ureteric mass extending to the vesicoureteric junction. He underwent laparoscopic radical nephroureterectomy (RNU) with partial cystectomy. Gross pathology confirmed a duplex collecting system with a distal ureteric tumor. Histopathology showed moderately differentiated SCC (G2) with invasion into periureteric fat and lymphovascular invasion. Adjacent squamous metaplasia and dysplasia supported an inflammation-carcinoma sequence. Surgical margins were negative (R0), and the kidney showed chronic pyelonephritis. DISCUSSION: Ureteric SCC is usually detected late due to nonspecific symptoms. RNU with bladder cuff excision remains the mainstay of treatment. Platinum-based adjuvant chemotherapy or immune checkpoint inhibitors may be considered for advanced or residual disease. The absence of lymph node dissection limits accurate staging and prognosis. Owing to its aggressive nature, close follow-up with cross-sectional imaging and cystoscopy is essential. CONCLUSION: This case illustrates ureteric SCC in a duplex collecting system associated with chronic stone disease, highlighting the role of inflammation-driven carcinogenesis. Early diagnosis, radical surgery, and multidisciplinary follow-up are essential for improving outcomes.