pho·​to·​phe·​re·​sis -fə-ˈrē-səs How to pronounce photopheresis (audio)
: an immunomodulating therapy used especially to treat cutaneous T-cell lymphomas that involves treating blood with a photoactive drug (as methoxsalen), obtaining a fraction rich in white blood cells, exposing the fraction to damaging ultraviolet radiation, and returning it to the body where it stimulates a therapeutic immunological response

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Cite this Entry

“Photopheresis.” Medical Dictionary, Merriam-Webster, Accessed 27 Mar. 2023.

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