THE INCIDENCE OF PELVIC ENDOMETRIOSIS IN ROCHESTER, MINNESOTA, 1970-1979

The primary objectives of the study were to measure the incidence of pelvic endometriosis among white females of reproductive age (15-49 years) in Rochester, Minnesota, during the period 1970-1979 and to determine the risk of endometriosis by age, marital status, nun status, and educational attainment in this population. An historical prospective design was used. Incident (newly diagnosed) cases were identified from community medical records, and person-years of risk in the study population were estimated from census data.^ Almost two-thirds of the incident cases had surgically verified endometriosis, while the remainder were diagnosed by clinical findings alone. Incidence rates were prepared first with histologically confirmed cases only and then with the successive inclusion of less certain cases: surgically visualized, clinically probable, and clinically possible. On this basis, overall incidence rates were 108.8 to 246.9 newly diagnosed cases per 100,000 person-years. The incidence of pelvic endometriosis was lowest for women 15-19 years of age, increased markedly through age 44, and then declined for women 45-49 years of age. A significantly greater risk of pelvic endometriosis in never married women was detected only when the numerator was limited to histologically confirmed cases. Among never married women 20-49 years of age, no significant difference in the risk of pelvic endometriosis by nun status was detected, but a trend toward a lower incidence in nuns was observed. Women with education beyond high school had a significantly higher incidence of endometriosis than women with less education.^ Cases in the four diagnostic groups differed greatly by age and marital status but were similar with respect to virtually all other characteristics, once age differences were considered. Reproductive history characteristics described included: age of menarche; history of menopause; total pregnancies; ages of first pregnancy, marriage, and sexual intercourse; years from menarche to first intercourse; years of ovulatory cycling; difficulty becoming pregnant; and delay of the first pregnancy by choice. How these characteristics of incident cases differ from those of women free of endometriosis needs to be studied in future research. ^

A systematic review and analysis of the association between endometriosis and ovarian cancer

Ovarian cancer is the most lethal of the gynecologic malignancies. The development of endometriosis has been shown to increase one's risk of ovarian cancer. Numerous studies have investigated this association, yet none have synthesized the available data. In a pooled analysis of cohort and case-control studies, the association between endometriosis and ovarian cancer was strengthened. Women who developed endometriosis-associated ovarian cancer were more likely to develop an early stage clear cell or endometrioid ovarian cancer histotypes and were more likely to have a better overall prognosis. The prognostic differences between endometriosis-associated ovarian cancer and ovarian cancer without an associated endometriosis may indicate genetic and environmental differences between groups.^

Learning curve for robotic-assisted laparoscopic colorectal surgery.

BACKGROUND: Robotic-assisted laparoscopic surgery (RALS) is evolving as an important surgical approach in the field of colorectal surgery. We aimed to evaluate the learning curve for RALS procedures involving resections of the rectum and rectosigmoid. METHODS: A series of 50 consecutive RALS procedures were performed between August 2008 and September 2009. Data were entered into a retrospective database and later abstracted for analysis. The surgical procedures included abdominoperineal resection (APR), anterior rectosigmoidectomy (AR), low anterior resection (LAR), and rectopexy (RP). Demographic data and intraoperative parameters including docking time (DT), surgeon console time (SCT), and total operative time (OT) were analyzed. The learning curve was evaluated using the cumulative sum (CUSUM) method. RESULTS: The procedures performed for 50 patients (54% male) included 25 AR (50%), 15 LAR (30%), 6 APR (12%), and 4 RP (8%). The mean age of the patients was 54.4 years, the mean BMI was 27.8 kg/m(2), and the median American Society of Anesthesiologists (ASA) classification was 2. The series had a mean DT of 14 min, a mean SCT of 115.1 min, and a mean OT of 246.1 min. The DT and SCT accounted for 6.3% and 46.8% of the OT, respectively. The SCT learning curve was analyzed. The CUSUM(SCT) learning curve was best modeled as a parabola, with equation CUSUM(SCT) in minutes equal to 0.73 × case number(2) - 31.54 × case number - 107.72 (R = 0.93). The learning curve consisted of three unique phases: phase 1 (the initial 15 cases), phase 2 (the middle 10 cases), and phase 3 (the subsequent cases). Phase 1 represented the initial learning curve, which spanned 15 cases. The phase 2 plateau represented increased competence with the robotic technology. Phase 3 was achieved after 25 cases and represented the mastery phase in which more challenging cases were managed. CONCLUSIONS: The three phases identified with CUSUM analysis of surgeon console time represented characteristic stages of the learning curve for robotic colorectal procedures. The data suggest that the learning phase was achieved after 15 to 25 cases.