Metástases Urinárias Secundárias ao Câncer de Pulmão: Revisão da Literatura e Análise Descritiva dos Resultados

Abstract

URINARY METASTASIS FROM LUNG CANCER: REVIEW OF THE LITERATURE AND DESCRIPTIVE ANALYSIS OF THE RESULTS Introduction: Lung cancer has the highest cancer-related mortality and 55% of patients already have distant metastases at the time of diagnosis. However, reports of retroperitoneal involvement by lung cancer are rare. Nevertheless, the suspicion of obstructive uropathy as a possible metastatic manifestation of this condition enables improvement of clinical reasoning and patient care. Objectives: To describe the clinical presentation of patients with metastatic involvement of the urinary tract secondary to lung cancer presenting clinical and therapeutic aspects of the cases covered in this review. Methods: The survey was conducted in the database MEDLINE via PubMed. The search strategy included "MeSH" terms related to lung cancer, metastasis, obstructive uropathy and upper urinary tract neoplasms in the title/abstract, limiting for humans and Portuguese and English languages. Studies addressing the metastatic involvement of the urinary tract without histopathological confirmation were excluded. The analysis of the selected studies was descriptive. Results: 1266 citations were obtained and 33 articles were selected, totaling the description of 45 case reports. There was significant male predominance (84.4%), as well as diagnosis and prior treatment of lung cancer (77.8%). The most prevalent histological subtype was squamous cell carcinoma (48.9%) and the most prevalent urinary metastatic involvement was renal involvement (75.5%). Apart from the urinary tract, the most important site of metastatic involvement was the liver (15.6%). Initial urinary symptoms were present in 68.9% of patients, most of whom had hematuria (55.6%) or pain (57.8%), especially on the lumbar spine, abdomen and flanks. Respiratory symptoms were less common. Nephrectomy was adopted in most patients (31.1%). High mortality (48.9%) was reported and 42.2% of the reports did not specify the outcome of the patient. Conclusion: Considering the high incidence of lung cancer, reports of urinary metastatic involvement are very rare. However, complaints of hematuria and flank pain in patients with lung cancer should raise the possibility of metastatic renal involvement, especially men with squamous histological subtype.