Abbott, Jason; Hawe, Jed; Hunter, David; Holmes, Michael; Finn, Paul; and Garry, Ray.  This included only patients with histologically proven endometriosis. Laparoscopic excision of endometriosis: a randomized, placebo-controlled trial.  Fertil Steril 2004;82:878–84.   Histology was used to exclude a diagnosis of endometriosis but not to analyze a difference in clinical response based on histologic results.  Thirty-nine women with histologically proven endometriosis were randomized to receive initially either a diagnostic procedure (the delayed surgical group) or full excisional surgery (the immediate surgery group. Significantly more of the 39 women operated on according to protocol reported symptomatic improvement after excisional surgery than after placebo: 16 of 20 (80%) vs. 6 of 19 (32%); 2(1)  9.3. Progression of disease at second surgery was demonstrated for women having only an initial diagnostic procedure in 45% of cases, with disease remaining static in 33% and improving in 22% of cases.  Nonresponsiveness to surgery was reported in 20% of cases. Abbott concluded that laparoscopic excision of endometriosis is more effective than placebo at reducing pain and improving quality of life. Surgery is associated with a 30% placebo response rate that is not dependent on severity of disease. Approximately 20% of women do not report an improvement after surgery for endometriosis.

Behera M, Vilos GA, Hollett-Caines J, Abu-Rafea B, Ahmad R. Laparoscopic findings, histopathologic evaluation, and clinical outcomes in women with chronic pelvic pain after hysterectomy and bilateral salpingo-oophorectomy. J Minim Invasive Gynecol 2006;13:431–435.  Histology was used to exclude a diagnosis of endometriosis but not to analyze a difference in clinical response based on histologic results or to determine a difference in response between sub-groups.  The most common histopathologic findings at laparoscopy in women with chronic pelvic pain after hysterectomy and bilateral salpingo-oophorectomy included adhesions, adnexal remnants, and endometriosis. Laparoscopic treatment of any pelvic pathologic condition improved pain symptoms in these women.

Fayez, Jamil A; Vogel, Matthew F.  Comparison of different treatment methods of endometriomas by laparoscopy.   Obstet Gynecol 78( 4, October):660-665 1991.  66 “endometriomas” were excised or stripped.  All had histologic analysis, but none (0%) had histologic confirmation.

Howard FM, El-Minawi AM and Sanchez RA.  Conscious pain mapping by laparoscopy in women with chronic pelvic pain. Obstet Gynecol 96:934-939, 2000.  There were 15 cases with successful conscious pain mapping and a visual diagnosis of endometriosis. In those cases endometriotic lesions were mapped as painful in seven. In all seven of those cases there was histologic confirmation of the diagnosis. In the remaining eight successfully mapped cases in which endometriotic lesions did not map positively, there was histologic confirmation of the diagnosis in only two cases. Thus, seven of nine cases with successful conscious pain mapping and histologically confirmed endometriosis mapped their pain to endometriotic lesions, compared with none of six successfully mapped cases in which the visual diagnosis of endometriosis was not histologically confirmed.  DCM Note:  No clarification of histology in the 9 with no confirmation.  Criteria, handling, preparation, etc. not stated.

Howard FM. Clinical predictors of a surgical diagnosis of endometriosis. J Min Invas Gynecol 12 supplement (5): s6-s7, 2005.  261 patients with chronic pelvic pain had surgical evaluation. 76% had undergone prior surgical evaluation and 20% had prior hysterectomy.  A diagnosis of endometriosis was based on the histological finding of ectopic endometrial glands and stroma.  Dysmenorrhea, dyspareunia and a past history of a diagnosis of endometriosis were not predictive of a diagnosis of endometriosis. A history of initial onset of pain at menarche or with menses had a positive predictive value of 72%, negative predictive value 64%, sensitivity of 37%, and specificity of 89%. Lower age and parity were associated with a diagnosis of endometriosis. Baseline pain levels and quality of life were not different in those with and without endometriosis. No findings on physical examination, including cervical deviation, cervical tenderness or paracervical tenderness were predictive.  In this population of women with chronic pelvic pain and prior clinical evaluation, many of the findings traditionally associated with endometriosis are not predictive of a diagnosis of endometriosis.

Ling FW and the Pelvic Pain Study Group.  Randomized controlled trial of depot leuprolide in patients with chronic pelvic pain and clinically suspected endometriosis. Obstet Gynecol. 1999;93(1):51-7.  Biopsies were taken but not used in the analysis. Women with moderate to severe pelvic pain of at least 6 months' duration unrelated to menstruation and incompletely relieved with nonsteroidal anti-inflammatory drugs were randomized to depot leuprolide or placebo. Women in the leuprolide group had clinically and statistically significant improvements from baseline in all pain measures.  Lupron response in 27 (82%) of 33 with and 8 (73%) of 11 with no endometriosis.  Placebo response in 15 (39%) of 38 with and 1 (16%) of 6 with no endometriosis. DCM Note: Ling's finding that there were good results with and without endometriosis reinforces the need to analyze the possibility that there may be no differences in results comparing patients with or without endometriosis.  That may include a diagnosis based on laparoscopy appearance, a diagnosis based on histology, negative histology and with other histology.  Testing those considerations might require sham surgery and thus require close examination of ethical concerns and reimbursement issues.  See Jenkins' 2007 abstract above.

Marcoux S, Maheux R, Berube S and the Canadian Collaborative Group on Endometriosis. Laparoscopic surgery in infertile women with minimal or mild endometriosis. NEJM 337:217-222, 1997. The diagnosis of endometriosis required the presence of one or more typical bluish or black lesions.  Red, clear, white and other appearances were not used.  Histologic confirmation was not used because it is not routine practice and removal of lesions by biopsy, especially in women who have few lesions, is a form of surgical treatment. DCM Note: Their definition agrees with Patrick Taylor's definitions and with my presentation at Laparoscopic Recognition of Endometriosis (2.2MB).

Nascu, Patricia C; Vilos, George A; Ettler, Hellen C; Abu-Rafea, Basim; Hollet-Caines, Jackie; Ahmad, Riad.  Histopathologic findings on uterosacral ligaments in women with chronic pelvic pain and visually normal pelvis at laparoscopy. J Min Invas Gynecol 13 201–204 2006.  Biopsies were taken and used in the analysis of frequencies but not used in the analysis of pain relief. Twenty-seven premenopausal women undergoing diagnostic laparoscopy for chronic pelvic pain (DCM note: The inclusion criteria include both cyclic and non-cyclic pain) had a normal pelvis on visual inspection.  23 completed the study.  All 23 (100%) had dysmenorrhea, 91% (21) had non-cyclic pain.  All patients underwent resection and histologic evaluation of the uterosacral ligaments. Pain relief was evaluated by use of a questionnaire administered before and at 3, 6, and 12 months after surgery. Despite normal laparoscopic appearance, microscopic endometriosis, endosalpingiosis, and inflammatory changes were found in uterosacral ligaments in 17 (63%) women with chronic pelvic pain.  Microscopic examination identified endometriosis in 2 (7.4%), endosalpingiosis in 3 (11.1%), and inflammation (Chronic lymphocytic infiltrate in 14 (51.9%) patients. Laparoscopic uterosacral ligament resection was associated with a 52% (14 of 24) reduction in dysmenorrhea, 62% (13 of 21) in non-cyclic pain and 40% (6 of 15) in dyspareunia.  8 (35%) of 21 patients no longer required medication for pain control. The number of patients missing work decreased from 52% to 8.7%. At 1 year, 10 patients (43.5%) reported no change compared with the preoperative period, and 1 (4.3%) had worsening of the symptoms.