Author Frank McCourt. (File photo)

The Pulitzer Prize-winning author of Angela's Ashes is battling skin cancer.

Frank McCourt, 78, is being treated for melanoma, according to his publicist Brian Belfiglio, but the writer's brother insists he's not as gravely ill as reports suggest.

Malachy McCourt states his sibling's cancer is in remission, adding McCourt is "a hearty fellow, and he's survived worse than this."

The writer's agent, Molly Friedrich, tells U.S. TV news show The Insider that McCourt was in the hospital about a month ago but is now back at home and undergoing chemotherapy.

She insists her client is "doing well".