Narrative medicine is based upon physicians' awareness of patients' narration of their suffering, their hopes, and how illness has affected them. It offers a model for improving health outcomes. To determine whether incorporating a narrative approach in patients with cancer decreases pain intensity and improves their global sense of well-being, we performed a randomized, single-blind controlled trial in adult patients with cancer and average pain intensity levels of at least 5/10. Two hundred thirty-four patients were randomized into three groups: (1) narrative (n=79), in which patients wrote a story about how cancer affected their lives for at least 20 minutes once a week for three weeks; (2) questionnaire (n=77), in which patients filled out the McGill Pain Questionnaire; and (3) control (n=78), in which patients came weekly to medical visits during which they received usual customary care. Patients rated their pain on a 0-10 scale and their well-being on a seven-point Likert scale weekly for eight weeks. Two raters independently evaluated the emotional content of the narratives. Pain intensity and sense of well-being were similar in all groups before and after treatment. Subgroup analyses showed that patients whose narratives had high emotional disclosure had significantly less pain and reported higher well-being scores than patients whose narratives were less emotional. Further study is needed to demonstrate whether the implementation of narrative medicine is associated with health benefits in this and other contexts.