Expression of Lewis (b) blood group antigen interferes with oral dienogest therapy among women with adenomyosis.

Abstract Adenomyosis is frequently observed in premenopausal women, and oral dienogest is the recommended treatment to target the underlying pathology and improve the symptoms. This retrospective study investigated the association of Lewis (b) antigen expression with outcomes of dienogest therapy among women with adenomyosis. Records from a total of 342 adenomyosis patients were analysed, who were prescribed with oral dienogest for a maximum of 16 weeks. Expression levels of Lewis (b) antigen were measured to categorize all patients into either Le (b)- and Le(b)+ groups. Treatment outcomes, in terms of uterine volume, menstrual flow, pain symptoms and quality of life, were compared between the two groups. While oral dienogest therapy showed considerable clinical efficacy in both groups of patients, the extent of improvements in treatment outcomes was significantly more pronounced in Le (b)- group than Le (b)+ group, with respect to treatment time, uterine symptoms, menstrual flow, pain symptoms and quality of life. No difference in adverse effects was observed between the two groups. Expression of Lewis (b) blood group antigen interferes with oral dialogist therapy among women with adenomyosis.