<P> During the show's third season, the New York Post's Robert Rorke deemed Izzie to be "the heart and soul" of Grey's Anatomy . He deemed her the show's heroine, and wrote that: "Izzie is a welcome, calming presence, despite the devastation she experienced when she failed to save her patient and fiance Denny Duquette . (...) Besides the formidable Dr. Bailey (Chandra Wilson), Izzie seems to be the only adult intern at Seattle Grace; the character has achieved a depth lacking in her fellow interns ." Eyder Peralta of The Houston Chronicle was critical of Izzie's ethics in cutting Denny's LVAD wire, writing that she "should not be practising medicine" and stating: "That's the reason I don't watch Grey's Anatomy, anymore, because the super hot blond chick can make an earth - shattering, fatal decision and she doesn't get canned ." </P> <P> The season four romance between Izzie and George proved unpopular with viewers, and resulted in a fan backlash among Alex and Izzie fans . The return of Izzie's deceased fiancé Denny and the resumption of their romance during the show's fifth season also proved unpopular with fans, and was deemed "the world's worst storyline" by Mary McNamara of the Los Angeles Times . McNamara was also critical of the episode "Now or Never", which saw Izzie flatline following neurosurgery, opining that Izzie ought to die . The episode in which Izzie married long - term love Alex received 15.3 million viewers, the largest television audience of the night . </P> <P> Izzie's cancer storyline received a mixed response from the medical community . Otis Brawley, chief medical officer at the American Cancer Society, commented that Izzie's treatment options were unrealistic . Whereas in the show she was offered the drug interleukin - 2, in reality the drug is never recommended to patients when melanoma has spread to the brain, as it can cause bleeding and strokes . Brawley explained that such patients would instead be offered radiosurgery . Conversely however, Tim Turnham, executive director of the Melanoma Research Foundation, praised Grey's Anatomy for bringing about greater public awareness of melanoma, stating: "We welcome the national spotlight Grey's Anatomy has created for melanoma and its efforts to encourage viewers to learn more about the importance of prevention, early detection and research ." </P>

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