Reevaluating response and failure of medical treatment of endometriosis: a systematic review

OBJECTIVE: To assess patient response rates to medical therapies used to treat endometriosis-associated pain. DESIGN: A systematic review with the use of Medline and Embase. SETTING: Not applicable. PATIENT(S): Women receiving medical therapy to treat endometriosis. INTERVENTIONS(S): None. MAIN OUTCOME MEASURE(S): The proportions of patients who: experienced no reduction in endometriosis-associated pain symptoms; had pain symptoms remaining at the end of the treatment period; had pain recurrence after treatment cessation; experienced an increase or no change in disease score during the study; were satisfied with treatment; and discontinued therapy owing to adverse events or lack of efficacy. The change in pain symptom severity experienced during and after treatment, as measured on the visual analog scale, was also assessed. RESULT(S): In total, 58 articles describing 125 treatment arms met the inclusion criteria. Data for the response of endometriosis-associated pain symptoms to treatment were presented in only 29 articles. The median proportions of women with no reduction in pain were 11%-19%; at the end of treatment, 5%-59% had pain remaining; and after follow-up, 17%-34% had experienced recurrence of pain symptoms after treatment cessation. After median study durations of 2-24 months, the median discontinuation rates due to adverse events or lack of efficacy were 5%-16%. CONCLUSION(S): Few studies of medical therapies for endometriosis report outcomes that are relevant to patients, and many women gain only limited or intermittent benefit from treatment.