Genetics of Bladder Malignant Tumors in Childhood

Abstract

Bladder masses are represented by either benign or malignant entities. Malignant bladder tumors are frequent causes of disease and death in western countries. However, in children they are less common. Additionally, different features are found in childhood, in which non epithelial tumors are more common than epithelial ones. Rhabdomyosarcoma is the most common pediatric bladder tumor, but many other types of lesions may be found, such as malignant rhabdoid tumor (MRT), inflammatory myofibroblastic tumor and neuroblastoma. Other rarer tumors described in literature include urothelial carcinoma and other epithelial neoplasms. Rhabdomyosarcoma is associated to a variety of genetic syndromes and many genes are involved in tumor development. PAX3-FKHR and PAX7-FKHR (P-F) fusion state has important implications in the pathogenesis and biology of RMS, and different genes alterations are involved in the pathogenesis of P-F negative and embryonal RMS, which are the subsets of tumors most frequently affecting the bladder. These genes include p53, MEF2, MYOG, Ptch1, Gli1, Gli3, Myf5, MyoD1, NF1, NRAS, KRAS, HRAS, FGFR4, PIK3CA, CTNNB1, FBXW7, IGF1R, PDGFRA, ERBB2/4, MET, BCOR. Malignant rhabdoid tumor (MRT) usually shows SMARCB1/INI1 alterations. Anaplastic lymphoma kinase (ALK) gene translocations are the most frequently associated alterations in inflammatory myofibroblastic tumor (IMT). Few genes alterations in urothelial neoplasms have been reported in the paediatric population, which are mainly related to deletion of p16/lnk4, overexpression of CK20 and overexpression of p53. Here, we reviewed available literature to identify genes associated to bladder malignancies in children and discussed their possible relationships with these tumors.

Myoepithelial Carcinoma of Urinary Bladder in a Pediatric Patient. A Case Report

“…Other malignant bladder tumors are neuroblastoma, urothelial carcinoma, myoepithelial carcinoma, etc. 5 Currently, there is no protocol for the treatment of myoepithelial carcinoma. The Italian experience of the "TREP (Tumori Rari in Et a Pediatrica) Project" is an alternative that has shown clinical benefit in children.…”

Congenital presentation of synchronous Atypical Teratoid Rhabdoid Tumor and Malignant Rhabdoid Tumor of the urinary bladder in a term infant

“…6 Cases of MRT in the bladder have been rarer, nonetheless, and alterations in SMARCB1/INI1 are usually implicated in such cases. 7 The patient was also found to have a synchronous malignant neoplasm of the brain, subsequently diagnosed as an AT/RT. Epidemiologically, AT/RT is a rare type of brain tumor, representing approximately 1-2% of all pediatric brain tumors.…”

Case report on a swift shift in uropathogens from Shigella flexneri to Escherichia coli: a thin line between bacterial persistence and reinfection

“…Some of these conditions may include kidney stone [25], painful bladder syndrome (interstitial cystitis) [26], possible renal tract malignancy, renal tuberculosis, urethritis and some sexually transmitted infections [27]. Since most of these conditions are seldom found in children [28][29][30][31], we still required more evidence to exclude a UTI for this patient, thus the need for a second urine culture. The second urine culture was quite necessary in this context as it helped to eliminate the possibilities of misdiagnosis and presented an unusual, rapid reinfection of the urinary tract by a completely different bacteria.…”