Assessing Adult Patients’ Understandings of Secondary Malignancy Risk Terms in Radiation Therapy Consent

Abstract

<h3>Purpose/Objective(s)</h3> Informed consent is an essential component of cancer care. The terms "second tumors" or "secondary tumors" are sometimes used in radiation therapy consent. Their incidences are sometimes described as "rare," although vary greatly from nearly negligible in patients treated with palliative intent, to 20% in young patients undergoing myeloablative total body irradiation. We evaluated whether patients without prior knowledge of radiation therapy interpret the terms in a way consistent with physician intent. <h3>Materials/Methods</h3> We screened 164 adult subjects who did not require medical interpreters at a university-affiliated family medicine clinic, excluding cancer patients and those with any prior knowledge of or experience with radiation treatment. One hundred subjects were eligible for and completed a 12-question multiple choice questionnaire, which assessed their understanding of the term "secondary tumor" or "second tumor", and how they would interpret the terms "small chance" or "rare" in the context of a "bad side effect." <h3>Results</h3> Twenty-nine percent of subjects correctly identified that "secondary tumors" referred to new and different tumors caused by treatment. Forty-nine percent thought the term referred to their original tumor recurring, and 22% thought the term referred to new and different tumors not caused by radiation therapy. Subjects with college degrees were not more likely to choose the correct answer than subjects without college degrees p=0.63. College degree status was not available for 5 subjects. Given choices between 1:10, 1:100, 1:1000, and 1:100,000, subjects associated "rare" with 1:1000 or 1:100,000 82% of the time. The term "small chance" was associated with 1:1000 or 1:100,000 59% of the time. <h3>Conclusion</h3> Adult non-cancer patients have a demonstrably different understanding than radiation oncologists of the terms "second tumor" or "secondary tumor." Additionally, patient understanding of the terms "rare" or "small chance" varies from secondary malignancy incidences in many clinical scenarios. Radiation oncologists should use clearer terms for secondary malignancies and their incidence.