Aromatase p-450 and prostaglandin E2 (PgE2) pathways are thought to be involved in the genesis of endometriotic implants. Aromatase plays an important role in estrogen biosynthesis by catalyzing the conversion of androstenedione and testosterone to estrone and estradiol. Although aromatase activity is not detectable in normal endometrium, it is found in eutopic endometrium and endometriotic lesions. Thus, aromatase inhibitors (AIs) are now being used as adjunctive therapy with medical therapies in refractory cases (59). A 2008 review of eight studies evaluated AIs for management of endometriosis and found that AIs combined with progestins or OCs or GnRH analogues decreased mean pain scores and lesion size and improved quality of life. In the only randomized controlled trial (97 women) evaluated in this meta-analysis, aromatase inhibitor (anastrozole) in combination with GnRH agonist significantly improved pain (P <0.0001) compared with GnRH agonist alone at 6-month follow-up, and there was no significant reduction in spine or hip bone density (60).
Laparoscopy and laparotomy are appropriate and for some patients, they are the preferred treatment for the management of secondary dysmenorrheal pain related to endometriosis that is unresponsive to hormonal agents (see also Chapter 17). Excellent operative skill is required to manage endometriosis surgically. Endometriotic lesions should be ablated or resected. Endometriomas must be removed with their capsule. Resection of endometriomas by ovarian cystectomy improves pain and fertility in women with chronic pelvic pain and endometriosis when compared to fenestration, drainage, and coagulation. In a randomized controlled trial of laser ablation for minimal to moderate endometriosis, over 90% of women felt improved at 1-year follow-up, and 87% of women with stage III to IV endometriosis were satisfied with the results at 1-year follow-up. Recurrent pain after 24 months is close to 50% (61).
In women who no longer desire fertility with severe secondary dysmenorrhea, hysterectomy with bilateral salpingo-oophorectomy (BSO) and removal of endometriosis lesions is the preferred treatment. Hysterectomy without BSO results in a higher rate of disease recurrence and a 30% reoperation rate. The risk of recurrent endometriosis with hormone replacement is small if combined estrogen-progestin preparations are used and unopposed estrogen is avoided.
There are limited data regarding outcomes for repeated conservative surgical procedures, including pelvic denervating procedures (61). The authors conclude that although re-operation is often considered the best option, the long-term outcome appears suboptimal with a cumulative probability of recurrent pain between 20% and 40% and of a further surgical procedure of at least 20%. Hysterectomy with BSO decreased the need for re-operation to treat pelvic pain by sixfold. Postoperative medical treatment with OCs can be effective (62). Re-operation in a symptomatic patient after previous conservative surgery should take into account the psychological state of the patient, desire for future fertility, and whether the pain responded to prior surgical therapy with at least 1, but preferably 3 to 5 years of pain relief.
Rectovaginal endometriosis is often deeply infiltrating, highly innervated, and associated with severe cyclic pelvic pain and dyspareunia (see also Chapter 17). These lesions can be surgically challenging for laparoscopic resection. Hormonal therapy can be effective. Vercellini et al.