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benign

Papillary fibroelastoma

A papillary fibroelastoma is a primary tumor of the heart that typically involves one of the heart valves. Papillary fibroelastomas, while considered uncommon, make up about 10 percent of all primary of the heart. They are the third most common type of primary tumor of the heart, behind myxomas and cardiac lipomas.

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Plain-language summary adapted from Wikipedia. Not medical advice.