Clinicopathological characteristics of urothelial bladder cancer in patients less than 40 years old.

Urothelial bladder cancer (UBC) is rare in young patients and as a result little information as to tumor type and clinical course are available. We present clinicopathological data of a large series of patients less than 40 years with bladder carcinoma. We included in this retrospective study covering the period from 1992 to 2013 patients less than 40 years with a first diagnosis of bladder cancer. Lesions were classified according to the WHO 2004 classification by uropathologists of ten centers. Stage, grade, multifocality, smoking habits, recurrence, and survival were studied. The cohort comprised of 152 patients, 113 males and 39 females with a mean age of 33.2 years. The large majority of the patients (142) was diagnosed with an urothelial carcinoma, the ten others with various histopathological diagnoses. In the age group less than 30 years old, 40.3 % of the cases concerned a papillary urothelial neoplasia of low malignant potential (PUNLMP). In the age group over 30 years, the proportion of PUNLMP decreased to 27.2 %. Only 5.6 % of the UBC was associated with carcinoma in situ. In 14.1 %, a high grade muscle invasive UC was found; 7.0 % had lymph node and 4.9 % distant metastasis at time of presentation. Four patients presented with a history of schistosomiasis; all had an infiltrating carcinoma. After initial resection, 36 patients relapsed, 17 % as PUNLMP, 53 % as pTa low grade, and 30 % as pTa-pT2 high grade UC. During follow-up, 6 % of the patients died. PUNLMP is the most frequent entity in this patient group. It is important that the PUNLMP entity is maintained in future classification systems.