The number of people with Merkel-cell carcinoma has more than doubled over a 20 year period.
John Paoli, a dermatologist and associate professor at the university's Sahlgrenska Academy, said the increase was "significant".
"In Sweden, an average of 24 new cases of Merkel-cell carcinoma were diagnosed each year during the period between 1993 and 2001," he said. "During the period of 2002 to 2011, the figure rose to 34 cases per year and in 2012 47 new cases of Merkel-cell carcinoma were discovered in Sweden."
Merkel-cell carcinoma is marked by fast-growing tumors that are often life-threatening. Doctors say getting an early diagnosis is crucial for a patients survival.