The rock band Heart has postponed its concert in Ottawa and all remaining shows on its tour as lead singer Ann Wilson undergoes treatment for cancer.

Wilson stated in an Instagram post on Tuesday that she has undergone surgery to remove a cancerous tumor and is recovering steadily, but her doctors have urged her to undergo preventive chemotherapy and take a break from performing.

The band was set to perform at the Canadian Tire Centre on August 1, and the organizer is not allowing refunds at this time.

More than 50 shows in venues and arenas in dozens of cities across the United States and Canada have been affected by the postponement.

Selected shows were supposed to feature performances by Def Leppard and Journey, but Heart has not announced whether those bands will join them on the rescheduled dates.

 The Wilson sisters, who have delivered hits such as "Magic Man," "Crazy on You," and "Alone," have been writing music together since the 1970s.  They were honored with a lifetime achievement award from the Recording Academy at the Rock and Roll Hall of Fame in 2023.