Tanimoto R, et al. - This trial was conducted to compare the recurrence-free survival in the single and two-time instillation of intravesical chemotherapy with pirarubicin (THP) in the case of solitary non-muscle invasive bladder cancer (NMIBC). For preventing the recurrence following complete resection of a solitary NMIBC, postoperative two-time intravesical instillation of THP was not found to be superior to single immediate installation.