Squamous cell carcinoma of the upper urinary tract in patients with urolithiasis: a systematic review

Abstract

Aim: To perform a systematic review on the current evidence about the squamous cell carcinoma (SCC) of the upper urinary tract in patients with urolithiasis.

Methods: A comprehensive bibliographic search on the MEDLINE, Scopus, Web of Science, and Cochrane Library databases was performed in December 2024. The SPIDER (Sample, Phenomenon of Interest, Design, Evaluation, Research type) framework was used to define inclusion criteria: male and female patients with urolithiasis (S); presence of SCC of the upper urinary tract (PI); prospective and retrospective studies (D); diagnosis based on imaging or pathological examination (E); qualitative, quantitative or mixed-methods (R). Quality of studies was assessed with Murad scale. Extracted data were synthesized in a narrative fashion. PROSPERO ID: “CRD42024625816”.

Results: A total of 35 articles were included. Eight case series (22.9%) and 27 case reports (77.1%) were analyzed. The overall quality of papers was low. Sixty-three cases of SCC in patients with urolithiasis (range: 1-11) were identified. The male-to-female ratio was 1.55, with a median age of 60 years (range: 25-87). Most common symptoms included pain (70%), hematuria (60%), and infection (40%). Staghorn stones (48%) and multiple stones (42%) were the most frequently encountered types of calculi. Almost all SCCs (97%) developed in the calico-pyelic system. A radiological suspicion of SCC was raised using imaging in 64% of patients, while in 52% of cases it was an incidental finding during pathological examination after nephrectomy for a non-functional kidney. Locally advanced disease was observed in 44% of patients, while metastasis was reported in 16%. The overall prognosis was poor, with a survival of approximately 6 months and 1-2 years for metastatic and locally advanced cases, respectively.

Conclusion: The available evidence is poor because the disease is extremely rare and the literature is limited to isolated case reports and small series. Therefore, robust conclusions cannot be drawn. Only a limited number of cases are reported in the literature and the current data prevent the estimation of prevalence or reliable pathophysiologic hypotheses. However, this tumor appears to be associated with a severe prognosis. Further investigations are needed to explore the topic and provide sufficient evidence to formulate clear recommendations.

Keywords

Chronic inflammation / nephrolithiasis / squamous cell carcinoma / stones / urolithiasis / upper urinary tract