The biological basis of medical treatment of endometriosis.

Efficacy of medical treatment for the management of endometriosis has been documented in several trials, but clinical results cannot always be maintained after the suspension of treatment. Surgical treatment, either laparotomic or laparoscopic, is affected by up to 20% in the recurrence of clinical symptoms after long-term follow-up. The appearance of endometriosis is heterogeneous, its functional status is variable and could lack hormone responsiveness. After medical, surgical or combined treatment the persistence of the failure of defence mechanisms accounts for the recurrence of disease. Unfortunately, all schemes to classify stages of endometriosis have so far failed to identify manifestations of the disease that respond in a predictable way to specific treatments.An analysis of the morphological appearance, implant biological activity and immune system involvement might better define the roles for medical management of endometriosis.