Avoidable admissions after minimally invasive hysterectomy.

OBJECTIVE: To determine the rate of avoidable admissions following anticipated same-day discharge for patients undergoing minimally invasive hysterectomy and to identify risk factors associated with such admissions. METHODS: A retrospective review was performed of patients who underwent a minimally invasive hysterectomy between March 2019 and July 2021 for a suspected gynecologic malignancy at a single tertiary care center. Pre-operatively, patients were assessed for same-day discharge versus planned admission. Reasons for day-of-surgery admission despite anticipated same-day discharge were categorized as anesthesia-related, system issues, intra-operative factors, post-operative pain, and social factors. Patients deemed not candidates for same-day discharge were defined as planned admissions. Indications were categorized as necessary or potentially avoidable. Descriptive and comparative statistics were used to summarize the cohort. RESULTS: In total, 372 patients were identified: 261 (70.2%) anticipated same-day discharges and 111 (29.8%) planned admissions. Of anticipated same-day discharges, 230/261 (88.1%) were successfully discharged, while 31/261 (11.9%) required admission. Reasons for unplanned admissions were anesthesia-related (14/31, 45.2%), system issues (7/31, 22.6%), intra-operative factors (5/31, 16.1%), post-operative pain (3/31, 9.7%), and social factors (2/31, 6.5%). Among the 111 pre-operatively planned admissions, 81 (73.0%) were necessary due to comorbidities or surgical complexity, while 30 (27.0%) were potentially avoidable because patients could have been optimized for same-day discharge. Opportunities for optimization pre-operatively included comorbidities (13/30, 43.3%), system issues (8/30, 26.7%), social factors (6/30, 20.0%), and provider preference (3/30, 10.0%). CONCLUSION: Most patients undergoing minimally invasive hysterectomy can be safely discharged the same day. Potentially avoidable admissions were primarily related to patient comorbidities that can be better optimized pre-operatively.

Decomposing the association of psychosocial wellbeing with all-cause mortality: the mediating role of physical health and lifestyle factors.

PURPOSE: This study quantified the effect of 48 psychosocial constructs on all-cause mortality using data from 7,698 individuals in the U.S. Health and Retirement Study. METHODS: Latent class analysis was used to divide participants into mutually exclusive psychosocial wellbeing groups (good, average, or poor) which was subsequently considered as the exposure. Mediation analysis was then conducted to determine the direct effect of the psychosocial wellbeing groups and the indirect (mediating) effects of physical health (functional status and comorbid conditions) and lifestyle factors (physical activity, smoking, and alcohol consumption) on overall survival. We also created a composite health index measure representing the summative effect of the mediators. RESULTS: We observed a strong and statistically significant total effect (TE) between survival time and psychosocial wellbeing group (survival time ratio (SR) = 1.73, 95% confidence interval (CI):1.50,2.01 when comparing good to poor). Mediation analysis revealed that the direct effect via psychosocial wellbeing group accounted for more than half of the TE (SR = 1.46, 95% CI:1.27,1.67). The composite health index measure mediated 36.2% of the TE with the natural indirect effect SR of 1.18 (95% CI:1.13,1.22). CONCLUSION: Our findings demonstrate the interconnectedness between psychosocial wellbeing and physical health and lifestyle factors on survival.

Genotyping-by-sequencing targets genic regions and improves resolution of genome-wide association studies in autotetraploid potato.

KEY MESSAGE: De novo genotyping in potato using methylation-sensitive GBS discovers SNPs largely confined to genic or gene-associated regions and displays enhanced effectiveness in estimating LD decay rates, population structure and detecting GWAS associations over 'fixed' SNP genotyping platform. Study also reports the genetic architectures including robust sequence-tagged marker-trait associations for sixteen important potato traits potentially carrying higher transferability across a wider range of germplasm. This study deploys recent advancements in polyploid analytical approaches to perform complex trait analyses in cultivated tetraploid potato. The study employs a 'fixed' SNP Infinium array platform and a 'flexible and open' genome complexity reduction-based sequencing method (GBS, genotyping-by-sequencing) to perform genome-wide association studies (GWAS) for several key potato traits including the assessment of population structure and linkage disequilibrium (LD) in the studied population. GBS SNPs discovered here were largely confined (~ 90%) to genic or gene-associated regions of the genome demonstrating the utility of using a methylation-sensitive restriction enzyme (PstI) for library construction. As compared to Infinium array SNPs, GBS SNPs displayed enhanced effectiveness in estimating LD decay rates and discriminating population subgroups. GWAS using a combined set of 30,363 SNPs identified 189 unique QTL marker-trait associations (QTL-MTAs) covering all studied traits. The majority of the QTL-MTAs were from GBS SNPs potentially illustrating the effectiveness of marker-dense de novo genotyping platforms in overcoming ascertainment bias and providing a more accurate correction for different levels of relatedness in GWAS models. GWAS also detected QTL 'hotspots' for several traits at previously known as well as newly identified genomic locations. Due to the current study exploiting genome-wide genotyping and de novo SNP discovery simultaneously on a large tetraploid panel representing a greater diversity of the cultivated potato gene pool, the reported sequence-tagged MTAs are likely to have higher transferability across a wider range of potato germplasm and increased utility for expediting genomics-assisted breeding for the several complex traits studied.

Small bite fascial closure technique reduces incisional hernia rates in gynecologic oncology patients.

BACKGROUND: The potential for the technique of small bite fascial closure in mitigating incisional hernias in gynecologic oncology patients still needs to be investigated. OBJECTIVE: To evaluate the impact of closure of small fascial bites compared with prior standard closure on incisional hernia rates in gynecologic oncology patients. METHODS: This is a retrospective cohort study comparing patient outcomes before and after the intervention at a single institution at a comprehensive cancer center. Patients who underwent laparotomy with a vertical midline incision for a suspected or known gynecologic malignancy with a 1-year follow-up were included. The pre-intervention cohort (large bites) had 'mass' or modified running Smead-Jones closure. In contrast, the post-intervention cohort had fascial bites taken 5-8 mm laterally with no more than 5 mm travel (small bites) closure using a 2-0 polydioxanone suture.The primary outcome was the incisional hernias rate determined by imaging or clinical examination within the first year of follow-up. Patient factors and peri-operative variates of interest were investigated for their association with hernia formation through univariate and multivariate analyses. These included age, body mass index (BMI), smoking history, estimated blood loss, pre-operative albumin, American Society of Anesthesia (ASA) physical status classification, or treatment with chemotherapy post-operatively. RESULTS: Of the 255 patients included, the total hernia rate was 12.5% (32/255 patients). Patient characteristics were similar in both cohorts. Small bite closure led to a significant reduction in hernia rates from 17.2% (22/128 patients) to 7.9% (10/127 patients), p=0.025. According to logistic regression modeling, small bite closure (OR=0.40, 95% CI 0.17 to 0.94, p=0.036) was independently associated with lower odds of hernia formation. Other factors associated with increased hernia rates were chemotherapy (OR=3.22, 95% CI 1.22 to 8.51, p=0.019) and obesity (OR=23.4, 95% CI 3.09 to 177, p=0.002). In obese patients, small bite closures led to maximal hernia rate reduction compared with large bites. CONCLUSIONS: The small bite closure technique effectively reduces hernia rates in gynecologic oncology patients undergoing midline laparotomy.

Implementation of routine venous thromboembolism prophylaxis during neoadjuvant chemotherapy for patients with ovarian cancer.

OBJECTIVE: To compare the venous thromboembolism (VTE) rate in patients with ovarian cancer undergoing neoadjuvant chemotherapy before and after implementing routine thromboprophylaxis. METHODS: This is a quasi-experimental pre-post study evaluating the VTE rate in patients with ovarian cancer who received neoadjuvant chemotherapy following a quality improvement initiative of routine thromboprophylaxis within a single healthcare system that started in January 2017. Patients were excluded if VTE was diagnosed before initiating chemotherapy. Patient factors and perioperative variables of interest were investigated for their association with VTE through univariate and multivariate models. RESULTS: Of the 136 patients in the pre-implementation group, 3.7% (n = 5) received thromboprophylaxis. Of the 154 patients in the post-implementation group, 65.6% (n = 101) received thromboprophylaxis. Provider compliance varied from 51% in 2019 to 79.3% in 2021. The overall rate of VTE, from the start of chemotherapy to the end of treatment, was 21.3% (n = 29) pre- and 8.4% (n = 13) in the post-implementation group (p < 0.01). There was no difference in major bleeding events between groups (0% vs. 0.68%, p = 0.63). On univariate analysis, thromboprophylaxis (OR 0.19; 95% CI 0.07-0.52) and post-implementation period (OR 0.34; 95% CI 0.17-0.69) were associated with a decreased risk of any VTE during primary treatment. On multivariate analysis, only thromboprophylaxis remained significantly associated with reduced VTE rates (aOR 0.19; 95% CI 0.07-0.53). CONCLUSION: Routine thromboprophylaxis during neoadjuvant chemotherapy is associated with reduced risk of VTE throughout primary treatment and is not associated with increased bleeding events.

Acquired factor VIII inhibitor caused by solid tumor malignancy.

•Factor VIII inhibitor can be acquired in gynecologic and other malignancies.•The disorder can develop along any timeline of malignancy diagnosis.•Common presentation is uncontrolled bleeding not managed by common interventions.•Treatment requires hemostatic control and an immunosuppressive regimen.

A framework for assessing interactions for risk stratification models: the example of ovarian cancer.

Generally, risk stratification models for cancer use effect estimates from risk/protective factor analyses that have not assessed potential interactions between these exposures. We have developed a 4-criterion framework for assessing interactions that includes statistical, qualitative, biological, and practical approaches. We present the application of this framework in an ovarian cancer setting because this is an important step in developing more accurate risk stratification models. Using data from 9 case-control studies in the Ovarian Cancer Association Consortium, we conducted a comprehensive analysis of interactions among 15 unequivocal risk and protective factors for ovarian cancer (including 14 non-genetic factors and a 36-variant polygenic score) with age and menopausal status. Pairwise interactions between the risk/protective factors were also assessed. We found that menopausal status modifies the association among endometriosis, first-degree family history of ovarian cancer, breastfeeding, and depot-medroxyprogesterone acetate use and disease risk, highlighting the importance of understanding multiplicative interactions when developing risk prediction models.

A comparative study on behavior, awareness and belief about cervical cancer among rural and urban women in Vietnam.

Cervical cancer is the second most common gynecologic cancer in Vietnam but based on the literature, only ~25% of Vietnamese women reported ever being screened for cervical cancer. To inform strategies to reduce the cervical cancer burden in Southern Vietnam where disease incidence is higher than the national average, this study examined behaviors, awareness, barriers, and beliefs about cervical cancer screening among rural and urban women in this geographical region. In October-November 2021, we conducted a cross-sectional study among 196 rural and 202 urban women in Southern Vietnam; participants completed a cervical cancer screening questionnaire. Descriptive analyses and rural-urban differences in screening behavior, awareness, barriers, and beliefs are presented. About half of the rural and urban participants reported ever being screened for cervical cancer. Most participants showed high perceived severity of cervical cancer and benefits of screening. Further, they reported that they would screen if it was recommended by doctors and/or friends/family. However, most women showed low awareness and perceived susceptibility to cervical cancer. Logistical and psychosocial barriers to physician-based screening methods were reported. Based on our results, the World Health Organization 2030 goals for cervical cancer screening are not currently met in Southern Vietnam. Increasing health literacy and engaging doctors and family members/social networks emerged as important avenues to improve screening. HPV (Human papillomavirus) self-sampling is also a potential approach to increase uptake of cervical cancer screening given the identified psychosocial and logistical barriers.

Pelvic Recovery After Endometrial Cancer Treatment: Patient-Reported Outcomes and MRI Findings.

RATIONALE AND OBJECTIVES: Most women with endometrial cancer (EC) have an excellent prognosis and may be cured. However, treatment-related pelvic functional impacts may affect long-term quality of life. To better understand these concerns, we explored correlations between patient-reported outcomes and pelvic magnetic resonance imaging (MRI) features in women treated for EC. MATERIALS AND METHODS: Women with histologic diagnosis of EC were consented preoperatively and completed the validated Female Sexual Function Index (FSFI) and Pelvic Floor Dysfunction Index (PFDI) questionnaires at preoperative, 6-week, and 6-month follow-up visits. Pelvic MRIs with dynamic pelvic floor sequences were performed at 6 weeks and 6 months. RESULTS: A total of 33 women participated in this prospective pilot study. Only 53.7% had been asked about sexual function by providers while 92.4% thought they should have been. Sexual function became more important to women over time. Baseline FSFI was low, declined at 6 weeks, and climbed above baseline at 6 months. Hyperintense vaginal wall signal on T2-weighted images (10.9 vs. 4.8, p = .002) and intact Kegel function (9.8 vs. 4.8, p = .03) were associated with higher FSFI. PFDI scores trended toward improved pelvic floor function over time. Pelvic adhesions on MRI were associated with better pelvic floor function (23.0 vs. 54.9, p = .003). Urethral hypermobility (48.4 vs. 21.7, p = .01), cystocele (65.6 vs. 24.8, p < .0001), and rectocele (58.8 vs. 18.8, p < .0001) predicted worse pelvic floor function. CONCLUSION: Use of pelvic MRI to quantify anatomic and tissue changes may facilitate risk stratification and response assessment for pelvic floor and sexual dysfunction. Patients articulated the need for attention to these outcomes during EC treatment.

Provider compliance with a tailored opioid prescribing calculator in gynecologic surgery.

OBJECTIVE: To evaluate the impact a tailored opioid prescription calculator has on meeting individual patient opioid needs while avoiding opioid over prescriptions. METHODS: Our group previously developed and published an opioid prescribing calculator incorporating patient risk factors (history of depression, anxiety, chronic opioid use, substance abuse disorder, and/or chronic pain) and type of surgery (laparotomy or laparoscopy). This calculator was implemented on 1/1/2021 and its impact on opioid prescriptions was evaluated until 12/31/21. The primary outcome of the present study is to determine prescriber compliance with the calculator (defined as not overprescribing from the number of pills indicated by the calculator). The secondary outcome is to determine the excess prescription rate (defined as proportion of patients reporting more than 3 pills remaining at 30 days post-surgery). Refill rates and pain related patient phone calls were collected. Descriptive statistics were used to summarize the cohort. RESULTS: Of the 355 patients included, 54.7% (N = 194) underwent laparoscopy and 45.4% (N = 161) underwent laparotomy. One hundred and forty-two patients (40%) had at least one risk factor for opioid usage. The median number of opioid pills prescribed following laparoscopy was 3 (range 0-15) and 6 (0-20) after laparotomy. The prescriber compliance was 88.2% and the excess prescription rate was 25.1% (N = 89 patients). CONCLUSIONS: Our tailored opioid calculator has a high prescriber compliance. Implementation of this calculator led to a standardization of tailored opioid prescribing, while limiting the number of over prescriptions. A free web version of the calculator can be easily accessed at www.opioidcalculator.org.

Psychosocial assessment tools for children and young people aged 5-18 years: A rapid review of the literature.

AIM: Schools are a key platform for health promotion and a point of connection to local health-care services, with an almost universal reach across the child and adolescent population. This study sought to determine whether validated psychosocial assessment tools exist for a school-based nursing program that would assist in providing an initial health assessment to identify and understand the needs of children and young people referred to the nurse, with the outcome of appropriate connection to external health and wellbeing services. METHODS: Rapid evidence assessment methodology was utilised to identify validated tools that could identify psychosocial concerns in children and young people aged 5-18 years. We identified articles from peer-reviewed journals via three electronic bibliographic databases (PubMed, Embase and CINAHL). We then extended the search for evidence through a search of the grey literature. RESULTS: From 3963 peer-reviewed articles found in the database search, 10 relevant peer-reviewed publications met inclusion criteria. In combination with 12 grey literature sources, 33 tools were identified. These included self-report tools (typically for children aged 11 years and older), parent-report and teacher-report tools. We identified the six most promising psychosocial assessment tools. However, there was limited description about implementation within school-based nursing programs. CONCLUSIONS: Several tools exist that show promise in assisting school-based nursing programs to conduct preliminary psychosocial assessments for children and young people. The introduction of any tools into practice would require implementation guidance and evaluation, including how and when they should be used, and when referral and follow-up is required.

Lifestyle and personal factors associated with having macroscopic residual disease after ovarian cancer primary cytoreductive surgery.

OBJECTIVE: The presence of macroscopic residual disease after primary cytoreductive surgery (PCS) is an important factor influencing survival for patients with high-grade serous ovarian cancer (HGSC). More research is needed to identify factors associated with having macroscopic residual disease. We analyzed 12 lifestyle and personal exposures known to be related to ovarian cancer risk or inflammation to identify those associated with having residual disease after surgery. METHODS: This analysis used data on 2054 patients with advanced stage HGSC from the Ovarian Cancer Association Consortium. The exposures were body mass index, breastfeeding, oral contraceptive use, depot-medroxyprogesterone acetate use, endometriosis, first-degree family history of ovarian cancer, incomplete pregnancy, menopausal hormone therapy use, menopausal status, parity, smoking, and tubal ligation. Logistic regression models were fit to assess the association between these exposures and having residual disease following PCS. RESULTS: Menopausal estrogen-only therapy (ET) use was associated with 33% lower odds of having macroscopic residual disease compared to never use (OR = 0.67, 95%CI 0.46-0.97, p = 0.033). Compared to nulliparous women, parous women who did not breastfeed had 36% lower odds of having residual disease (OR = 0.64, 95%CI 0.43-0.94, p = 0.022), while there was no association among parous women who breastfed (OR = 0.90, 95%CI 0.65-1.25, p = 0.53). CONCLUSIONS: The association between ET and having no macroscopic residual disease is plausible given a strong underlying biologic hypothesis between this exposure and diagnosis with HGSC. If this or the parity finding is replicated, these factors could be included in risk stratification models to determine whether HGSC patients should receive PCS or neoadjuvant chemotherapy.

Inhibition of Tumor Microenvironment Cytokine Signaling Sensitizes Ovarian Cancer Cells to Antiestrogen Therapy.

Antiestrogen therapy (AET) is an alternative to cytotoxic chemotherapy for recurrent ovarian cancer, yet the often short duration of response suggests mechanisms of resistance. We previously demonstrated that tumor microenvironment interleukin-6/leukemia inhibitory factor (IL6/LIF) cytokines induce tumor cell JAK-STAT signaling to promote cancer growth. Crosstalk between estrogen signaling and cytokine signaling has been reported. Therefore, we sought to characterize the impact of IL6/LIF signaling on estrogen signaling in epithelial ovarian cancer and investigate the efficacy of combination therapy. We first assessed patient tumors for cytokine expression and compared it with response to AET to determine clinical relevance. In vitro, we determined the effect of IL6/LIF on estrogen receptor expression and signaling. Cell viability assays were used to determine the efficacy and potential synergy of cytokine blockade and AET. We then extended studies to animal models, incorporating patient-derived stromal cells. Our results demonstrated shorter progression-free interval on AET in patients with stromal IL6/LIF expression. In vitro, IL6/LIF increased tumor cell estrogen receptor expression and signaling, and combination cytokine blockade and AET resulted in synergistic inhibition of tumor cell growth. The anticancer effect was verified in a mouse model. In conclusion, due to crosstalk between IL6/LIF cytokine signaling and estrogen signaling, dual blockade is a potential new treatment approach for ovarian cancer.

The "Sweet Spot" of Targeting Tumor Metabolism in Ovarian Cancers.

The objective of this review is to explore the metabolomic environment of epithelial ovarian cancer that contributes to chemoresistance and to use this knowledge to identify possible targets for therapeutic intervention. The Warburg effect describes increased glucose uptake and lactate production in cancer cells. In ovarian cancer, we require a better understanding of how cancer cells reprogram their glycogen metabolism to overcome their nutrient deficient environment and become chemoresistant. Glucose metabolism in ovarian cancer cells has been proposed to be influenced by altered fatty acid metabolism, oxidative phosphorylation, and acidification of the tumor microenvironment. We investigate several markers of altered metabolism in ovarian cancer including hypoxia-induced factor 1, VEGF, leptin, insulin-like growth factors, and glucose transporters. We also discuss the signaling pathways involved with these biomarkers including PI3K/AKT/mTOR, JAK/STAT and OXPHOS. This review outlines potential metabolic targets to overcome chemoresistance in ovarian cancer. Continued research of the metabolic changes in ovarian cancer is needed to identify and target these alterations to improve treatment approaches.

NCCN Guidelines® Insights: Ovarian Cancer, Version 3.2022.

Epithelial ovarian cancer is the leading cause of death from gynecologic cancer in the United States, with less than half of patients living >5 years following diagnosis. The NCCN Guidelines for Ovarian Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with ovarian, fallopian tube, and primary peritoneal cancers. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including revised guidance on alternative chemotherapy regimens for patients with advanced age and/or comorbidities, a new algorithm for recurrent low-grade serous carcinoma based on developing research and novel therapeutic agents, and updated language regarding tumor molecular analysis applications in ovarian cancer.

Phase I trial of ribociclib with platinum chemotherapy in ovarian cancer.

BACKGROUNDNew therapeutic combinations to improve outcomes of patients with ovarian cancer are clearly needed. Preclinical studies with ribociclib (LEE-011), a CDK4/6 cell cycle checkpoint inhibitor, demonstrate a synergistic effect with platinum chemotherapy and efficacy as a maintenance therapy after chemotherapy. We tested the safety and initial efficacy of ribociclib in combination with platinum-based chemotherapy in recurrent ovarian cancer.METHODSThis phase I trial combined weekly carboplatin and paclitaxel chemotherapy with ribociclib, followed by ribociclib maintenance in patients with recurrent platinum-sensitive ovarian cancer. Primary objectives were safety and maximum tolerated dose (MTD) of ribociclib when given with platinum and taxane chemotherapy. Secondary endpoints were response rate (RR) and progression-free survival (PFS).RESULTSThirty-five patients were enrolled. Patients had a mean of 2.5 prior lines of chemotherapy, and 51% received prior maintenance therapy with poly(ADP-ribose) polymerase inhibitors and/or bevacizumab. The MTD was 400 mg. The most common adverse events included anemia (82.9%), neutropenia (82.9%), fatigue (82.9%), and nausea (77.1%). The overall RR was 79.3%, with a stable disease rate of 18%, resulting in a clinical benefit rate of 96.6%. Median PFS was 11.4 months. RR and PFS did not differ based on the number of lines of prior chemotherapy or prior maintenance therapy.CONCLUSIONThis work demonstrates that the combination of ribociclib with chemotherapy in ovarian cancer is feasible and safe. With a clinical benefit rate of 97%, this work provides encouraging evidence of clinical efficacy in patients with recurrent platinum-sensitive disease.TRIAL REGISTRATIONClinicalTrials.gov NCT03056833.FUNDINGThis investigator-initiated trial was supported by Novartis, which provided drugs and funds for trial execution.

High Prediagnosis Inflammation-Related Risk Score Associated with Decreased Ovarian Cancer Survival.

BACKGROUND: There is suggestive evidence that inflammation is related to ovarian cancer survival. However, more research is needed to identify inflammation-related factors that are associated with ovarian cancer survival and to determine their combined effects. METHODS: This analysis used pooled data on 8,147 women with invasive epithelial ovarian cancer from the Ovarian Cancer Association Consortium. The prediagnosis inflammation-related exposures of interest included alcohol use; aspirin use; other nonsteroidal anti-inflammatory drug use; body mass index; environmental tobacco smoke exposure; history of pelvic inflammatory disease, polycystic ovarian syndrome, and endometriosis; menopausal hormone therapy use; physical inactivity; smoking status; and talc use. Using Cox proportional hazards models, the relationship between each exposure and survival was assessed in 50% of the data. A weighted inflammation-related risk score (IRRS) was developed, and its association with survival was assessed using Cox proportional hazards models in the remaining 50% of the data. RESULTS: There was a statistically significant trend of increasing risk of death per quartile of the IRRS [HR = 1.09; 95% confidence interval (CI), 1.03-1.14]. Women in the upper quartile of the IRRS had a 31% higher death rate compared with the lowest quartile (95% CI, 1.11-1.54). CONCLUSIONS: A higher prediagnosis IRRS was associated with an increased mortality risk after an ovarian cancer diagnosis. Further investigation is warranted to evaluate whether postdiagnosis exposures are also associated with survival. IMPACT: Given that pre- and postdiagnosis exposures are often correlated and many are modifiable, our study results can ultimately motivate the development of behavioral recommendations to enhance survival among patients with ovarian cancer.

Endometriosis and menopausal hormone therapy impact the hysterectomy-ovarian cancer association.

OBJECTIVE: To evaluate the association between hysterectomy and ovarian cancer, and to understand how hormone therapy (HT) use and endometriosis affect this association. METHODS: We conducted a pooled analysis of self-reported data from 11 case-control studies in the Ovarian Cancer Association Consortium (OCAC). Women with (n = 5350) and without ovarian cancer (n = 7544) who never used HT or exclusively used either estrogen-only therapy (ET) or estrogen+progestin therapy (EPT) were included. Risk of invasive epithelial ovarian cancer adjusted for duration of ET and EPT use and stratified on history of endometriosis was determined using odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Overall and among women without endometriosis, there was a positive association between ovarian cancer risk and hysterectomy (OR = 1.19, 95% CI 1.09-1.31 and OR = 1.20, 95% CI 1.09-1.32, respectively), but no association upon adjusting for duration of ET and EPT use (OR = 1.04, 95% CI 0.94-1.16 and OR = 1.06, 95% CI 0.95-1.18, respectively). Among women with a history of endometriosis, there was a slight inverse association between hysterectomy and ovarian cancer risk (OR = 0.93, 95% CI 0.69-1.26), but this association became stronger and statistically significant after adjusting for duration of ET and EPT use (OR = 0.69, 95% CI 0.48-0.99). CONCLUSIONS: The hysterectomy-ovarian cancer association is complex and cannot be understood without considering duration of ET and EPT use and history of endometriosis. Failure to take these exposures into account in prior studies casts doubt on their conclusions. Overall, hysterectomy is not risk-reducing for ovarian cancer, however the inverse association among women with endometriosis warrants further investigation.