Urinary tract infection increases subsequent urinary tract cancer risk: A population‐based cohort study

Abstract

This study examines the possible association between urinary tract infection (UTI) and urinary tract cancer (UTC). Data from the National Health Insurance system of Taiwan were used for the analysis. The UTI cohort included 70 116 patients who were diagnosed and recruited between 1997 and 2010. Each patient was randomly frequency-matched with two people without UTI from the general population based on their age, sex, and month of UTI diagnosis. Cox's proportional hazard regression analysis was used to estimate the effects of UTI on UTC risk until the end of follow-up on December 31, 2010. Patients with UTI had a significantly higher risk of developing UTC than healthy people (adjusted hazard ratio, 4.66; 95% confidence interval, 3.55-6.10). Further analyses indicated that risks are potentially related to the level of the lesion site. This study indicated that patients with UTI had a higher risk of developing UTC. (Cancer Sci 2013; 104: 619-623) U rinary tract infection (UTI) is the most common extraintestinal infectious disease entity in women worldwide. Approximately 50% of women have at least one symptomatic UTI during their lifetime, and recurrent episodes are common.(1) Several infections are related to the development of cancer, including human papilloma virus-associated cancer such as head and neck cancers, cervical cancer, (2,3) hepatitis B and C virus-associated liver cancer, (4,5) Epstein-Barr virusrelated nasopharyngeal carcinoma and lymphoma, (6) and Helicobacter pylori infection-induced gastric cancer. (7) Chronic inflammation induced by bladder infection could have a role in human bladder cancer development. (8,9) The relationship between schistosomiasis and bladder cancer has been confirmed.(10) Several case-control studies focused on the connection between UTI and bladder cancer risk and, although most showed that patients with UTI had a higher risk of bladder cancer, results were inconsistent. (11,12) Compared to bladder cancer, significantly fewer studies have discussed the connection between UTI and renal pelvis ⁄ ureter cancer because of its relative rarity. Studies regarding this issue showed either non-significant findings (13) or inconclusive results.Several mechanisms were proposed for explaining the association between infection and bladder cancer. (11,12) First, chronic inflammation of the bladder may induce urinary retention and stasis, which can potentially increase exposure and absorption of carcinogens present in the urine.(15) Second, bacterial flora in the urine may contribute to the production of nitrites that are converted to carcinogenic nitrosamines. (16) This study attempts to determine if there is a higher risk of bladder cancer for patients with UTI by examining a Taiwanese cohort. Because of an unusually high incidence of upper urinary tract urothelial carcinoma in Taiwan, (17) upper urinary tract cancer was of primary interest, but ensuing investigations were extended to cover all urinary tract cancers (UTC) except renal cell carcinoma. The results in this study were g...

A nationwide population‐based cohort study on tonsillectomy and subsequent cancer incidence

“…Our research group recently conducted a cohort study using NHIRD to evaluate the relationship between urinary tract infection and subsequent urinary tract cancer risk. Our positive findings encouraged us to conduct a study with a similar design to determine whether tonsillectomy relates to the risk of developing cancer.…”

Prevalence of Asymptomatic Bacteriuria and Antibiotic Susceptibility Patterns of Bacterial Isolates among Cancer Patients and Healthy Blood Donors at the University of Gondar Specialized Hospital

“…A study by Fan et al in 2017 had also identified an association between prostate cancer and bacteriuria [40]. Another study by Sun et al in 2013 had also confirmed the association among urinary tract cancers and asymptomatic bacteriuria [8]. is difference might be due to the variation in study design and characteristics of the study population.…”

“…Bacteriuria is the presence of microbial pathogens in the urethra, bladder, ureter, and pelvis of the kidney [5,6]. Escherichia coli, Klebsiella pneumonia, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae are the leading cause of urinary tract infections [7,8]. Obstruction of the urinary tract, use of a catheter, immunocompromised condition, estrogen deficiency, genetic predisposition, and sexual intercourse are common risk factors for urinary tract infection [9,10].…”

Recurrent urinary tract infection and risk of bladder cancer in the Nijmegen bladder cancer study

“…Several epidemiological studies, most from the second half of the twentieth century and conducted in small populations, have investigated the association between episodes of (lower) UTI and the risk of urinary bladder cancer (UBC). The majority of these studies report increased UBC risks for any vs no UTI, in both men and women ( Wynder et al , 1963 ; Dunham et al , 1968 ; Howe et al , 1980 ; Kantor et al , 1984 ; Claude et al , 1986 ; La Vecchia et al , 1991 ; Kunze et al , 1992 ; Sturgeon et al , 1994 ; Jhamb et al 2007 ; Sun et al , 2013 ), whereas some do not support a positive association ( Piper et al , 1986 ; Kjaer et al , 1989 ; González et al , 1991 ; Jiang et al , 2009 ). A few studies specifically address the number of UTI episodes or the duration between UTI and UBC diagnosis, the latter to prevent potential misclassification.…”