Joshua Rothman in The New Yorker:
One day in the nineteen-eighties, a woman went to the hospital for cancer surgery. The procedure was a success, and all of the cancer was removed. In the weeks afterward, though, she felt that something was wrong. She went back to her surgeon, who reassured her that the cancer was gone; she consulted a psychiatrist, who gave her pills for depression. Nothing helped—she grew certain that she was going to die. She met her surgeon a second time. When he told her, once again, that everything was fine, she suddenly blurted out, “The black stuff—you didn’t get the black stuff!” The surgeon’s eyes widened. He remembered that, during the operation, he had idly complained to a colleague about the black mold in his bathroom, which he could not remove no matter what he did. The cancer had been in the woman’s abdomen, and during the operation she had been under general anesthesia; even so, it seemed that the surgeon’s words had lodged in her mind. As soon as she discovered what had happened, her anxiety dissipated.
More here.