Somatic Mutations Profile of a Young Patient With Metastatic Urothelial Carcinoma Reveals Mutations in Genes Involved in Ion Channels

Background: Urothelial carcinoma is the most common malignancy of the bladder and is primarily considered as a disease of the elderly. Studies that address bladder tumor occurrence in young age groups are rare. Case Presentation: A 19-year-old male presented with a gross total painless hematuria. A histology after biopsy revealed a high-grade transitional cell carcinoma with lymph node metastasis. The patient succumbed to the disease on day 72 of the treatment. Here, we used whole-exome sequencing of a paired tumor-normal sample to identify the somatic mutations and the possible targets of treatment. Result: We predicted eight potential driver mutations (TP53 p.V157L, RB1 c.1498+1G>T, MED23 p.L1127P, CTNND1 p.S713C, NSD1 p.P2212A, MED17 p.G556V, DPYD p.Q814K, and SPEN p.S1078(*)). In addition, we predicted deleterious mutations in genes involved in the ion channels (CACNA1S p.E1581K, CACNG1 p.P71T, CACNG8 p.G404W, GRIN2B p.A1096T, KCNC1 p.G16V, KCNH4 p.E874K, KCNK9 p.R131S, P2RX7 p.A296D, and SCN8A p.R558H). Conclusions: Most likely, mutations in genes involved in ion channels may be responsible for the aggressive behavior of a tumor. Ion channels are the second largest class of drug targets, and may thus serve as a putative potential therapeutic target in advanced stage urothelial carcinoma.