The natural course of bacillus Calmette-Guerin induced bladder lesions:A long-term follow-up study and systematic review

摘要

Objective:Bacillus Calmette-Gue´rin(BCG)instillation is the standard adjuvant treatment for intermediate-and high-risk non-muscle-invasive bladder cancer after transurethral resection.Nevertheless,its toxicity often causes bladder complications.On follow-up cystoscopy,post-BCG bladder lesions can be pathologically benign,urothelial carcinoma recurrence,or other types of bladder malignancy.Only a small number of case reports have been published on post-BCG bladder lesions.Their clinical features,natural course,and management remain unknown.Methods:We retrospectively studied cystoscopic videos and medical records of BCG-treated bladder cancer patients at our center.During a long-term follow-up,we took biopsies on tumor-like lesions and described their changes.In addition,we summarized previous studies on post-BCG bladder lesions by systematic literature searching and review.Results:We described a series of three cases with post-BCG bladder lesions mimicking tumor recurrence from a total of 38 cases with follow-up data for more than 5 years.Those lesions could last,grow,or disappear spontaneously,and remain pathological benign for years.In systematic review,we identified and analyzed a total of 15 cases with post-BCG bladder lesions with detailed clinical information.Eleven of the 15 were benign and have a good prognosis with nephrogenic adenoma being the most common pathological type.Conclusion:Based on previous studies and our experience,benign lesions after BCG instillation cannot distinguish with cancer recurrence by cystoscopy alone,even under narrow band imaging mode.Nonetheless,given most of them have a good prognosis,random biopsy or transurethral resection might be spared in the patients with long-term negative biopsy and urine cytology.