Horne's illness has been rumored in music circles, and was first reported on the web site MusicalAmerica.com.

Horne is due to give masterclasses at Carnegie Hall January 24 and 27, part of "The Song Continues," a week-long, six-event series of recitals and masterclasses presented in partnership with the Marilyn Horne Foundation.

A statement released by CAMI said that "localized pancreatic cancer...allowing for recent significant breakthroughs in treatment, offers an excellent prognosis for a full recovery. Marilyn Horne is known throughout the world for not only her magnificent voice, but also for her tremendous energy and human spirit, which will, along with the love of her family and friends, see her through this challenge."

Horne was born in Bradford, Pennsylvania, in 1934, and studied at the University of Southern California. She made her debut in Smetana's The Bartered Bride at Los Angeles Guild Opera in 1954. From 1957 to 1960, Horne sang with Germany's Gelsenkirchen Opera Company, returning to the United States in 1960 to sing Marie in Berg's Wozzeck at San Francisco Opera.

She made her Covent Garden debut in 1964 (again in Wozzeck), at La Scala in 1969, and at the Metropolitan Opera in 1970. The latter performance, as Adalgisa in Bellini's Norma, was one of many performances with soprano Joan Sutherland.

Her signature roles include the title role of Handel's Rinaldo, Isabella in Rossini's L'italiana in Algeri, Amneris in Verdi's Aida, and Carmen.

In recent years, Horne has concentrated on working with young singers, directing the vocal program at the Music Academy of the West and supporting promising artists through the Marilyn Horne Foundation.