The cyst, a harmless polyp, has been sitting under the left vocal cord for several years but has grown larger recently and now needs to be surgically removed, Carola wrote in a post on Instagram.
"It is a delicate operation, but one that Dr. Johan has performed for many years on many other singers in the country with very good results," the artist wrote in the post.
That the operation is necessary became clear during a Christmas concert with Viktor Norén in Gothenburg.
"My voice broke, and I could barely make out the notes at all. I cried inside, but carried out the concert with the help of the choir and Viktor Norén."
After the surgery, Carola will have a longer recovery, and she wrote that she hopes to be back for her planned concerts in August.
