Complex sentence: Interest in Rife's claims was revived in some alternative medical circles by the book "The Cancer Cure That Worked" (1987), which claimed that Rife's work was successful but was suppressed by a conspiracy headed by the American Medical Association.
Split into simpler sentences: Interest in Rife's claims was revived in some alternative medical circles by the book "The Cancer Cure That Worked" (1987), which reported that Rife's work was successful. The book also claimed that his cure for cancer was suppressed by a conspiracy headed by the American Medical Association.