Madonna has canceled yet another concert date. This time in Lisbon, Portugal.<br />In the latest setback to her current tour, which has been blighted by delays and cancellations.<br />When fans arrived at Sunday's show in Lisbon, they were greeted with a message informing them it was cancelled.<br />Madonna had been scheduled to take the stage at the Coliseu theater at 8.30 p.m.<br />The 61-year-old superstar later told fans on Instagram that she was forced to cancel the show for medical reasons.
