Baboudjian M, Fourmarier M, Clement C, et al. - Radiation-induced cystitis can be effectively managed by performing intravesical instillation of high molecular weight sodium hyaluronate (HMW-HA).

• A total of 30 patients with radiation-induced cystitis were enrolled.

• The bladder was instilled weekly with a sterile disposable 50 ml prefilled solution containing 0.16% (80 mg/50 mL) HMW-HA (INSTYLAN).

• A total of 6 sessions were involved in the treatment (V1 to V6).

• A significant reduction in pelvic pain intensity (− 45.81%), hematuria (− 26.87%), total 24 h voids (− 23.92%) and the effect of urgencies on QoL (− 33.92%) was recorded at week 7 in the Intent-to-Treat analysis.

• Participants well-tolerated bladder instillation therapy: two treatment-related AEs (6.6%) were reported corresponding to two grade 1 hematuria.