Surgical treatment of endometriosis: location and patterns of disease at reoperation

OBJECTIVE: To assess the behavior of revised American Fertility Society stages I and II endometriosis after surgical treatment, by observation of location of pelvic involvement at reoperation. DESIGN: Prospective study. SETTING: Tertiary referral center at a university-based hospital. PATIENT(S): Thirty-nine women with persistent or recurrent chronic pelvic pain after laparoscopic excision or ablation of histologically confirmed endometriosis who underwent a second laparoscopy. INTERVENTION(S): Laparoscopic pelvic mapping and surgical treatment of endometriosis, followed by repeat laparoscopic pelvic mapping of endometriosis at a second laparoscopy. RESULT(S): Superficial peritoneal endometriosis (revised American Fertility Society stage I-II) endometriosis recurred in 37% of pelvic regions after surgical treatment. Endometriosis was more likely to recur in a treated pelvic region than an adjacent or distant pelvic region (relative risk 2.54; 95% confidence interval 1.63-3.97). A region adjacent to a previously affected pelvic region that was unaffected by endometriosis at the initial laparoscopy was more likely to have endometriosis at the second laparoscopy than a pelvic region distant from the treated pelvic region (relative risk 1.29; 95% confidence interval 0.84-2.0). Unaffected regions at initial laparoscopy had a low probability of having new endometriosis (11%) in the second laparoscopy. CONCLUSION(S): Recurrence of histologically proven endometriosis after surgical excision is more likely to cluster close to the original area of involvement, reflecting either incomplete excision at the initial surgery or a nonrandom favored implantation of new endometrial implants in adjacent peritoneum. Further studies are needed to elucidate the pathophysiology and mechanisms of recurrence of endometriosis.