** Shares of Lyell Immunopharma LYEL.O rise 15% to $11.70 premarket

** Co says 88% of patients with a type of blood cancer who were given LYEL's experimental cell therapy, called LYL314, had their tumors shrink or disappear after treatment in an early- to mid-stage trial

** LYEL says 72% of patients experienced a complete disappearance of all signs of their cancer following treatment with the therapy

** Up to last close, stock had fallen 21% YTD

(Reporting by Puyaan Singh)

((Puyaan.Singh@thomsonreuters.com;))