The announcement comes after Grönvall said in December that she had been re-diagnosed with breast cancer, 20 years after she was first treated for the disease. She also said at the time that she was canceling all of her performances for the next two months.
The Rainbow Gala is organized by the Rainbow Foundation and aims to highlight the rights and freedoms of LGBTQ people. This year's theme is pop music and other participants include Pernilla Wahlgren, Christer Lindarw, and Arja Saijonmaa.
The gala takes place at Intiman in Stockholm on April 20.
