Pembrolizumab with bevacizumab and cyclophosphamide for the treatment of recurrent ovarian clear cell carcinoma: A case series.

Introduction: Treatment for recurrent ovarian clear cell carcinoma (OCCC) is clinically challenging as response rates to traditional chemotherapy are low, and recurrence rates are high. Immunotherapy has shown promise for this ovarian cancer (OC) subtype, and tumor molecular testing allows for the identification of a patient population that might benefit most from this treatment. We describe the clinical course and somatic genomic testing of 4 patients who received pembrolizumab for recurrent OCCC concurrent with a combination of bevacizumab and/or cyclophosphamide. Methods: All patients with OCCC treated with immune checkpoint inhibitors (ICI) within a single health system between 2018 and 2023 (excluding those on clinical trials) were identified via retrospective chart review. Results: Four patients were included. The average age at diagnosis was 56.5 years, and the number of prior treatments ranged from 1 to 6. All patients received pembrolizumab combined with either bevacizumab and/or cyclophosphamide. All patients (n = 3) who received pembrolizumab and bevacizumab experienced a partial response. Responses were durable, ranging from 6 to 15 months. Somatic genomic testing results demonstrated microsatellite stability and low tumor mutational burden in all patient tumors, and 3 had AT-Rich Interaction Domain 1A gene (ARID1A) mutations. Notably, two patients had treatment-limiting toxicities, one with presumed immune-mediated grade 2 myocarditis, and another with grade 5 hepatitis. Conclusions: Pembrolizumab, combined with bevacizumab and cyclophosphamide, is a promising treatment option for patients with recurrent OCCC, though careful risk assessment and counseling regarding toxicities is necessary to maximize the safety and efficacy of this treatment regimen. Prospective studies are needed for validation.

Long-term disease-free survival with chemotherapy and pembrolizumab in a patient with unmeasurable, advanced stage dedifferentiated endometrial carcinoma.

Dedifferentiated endometrial carcinoma is a rare, highly aggressive subtype of endometrial cancer associated with poor survival outcomes. Current guidelines recommend treatment of advanced-stage disease with surgical staging or cytoreduction and platinum/taxane-based chemotherapy. Despite these approaches, the achievement of long-term remission or prolonged survival is challenging. Recent Phase III studies demonstrate that the addition of PD-1 inhibitors to standard chemotherapy significantly improves progression-free survival in patients with measurable, mismatch repair deficient (dMMR) and proficient (pMMR) advanced-stage or recurrent endometrial carcinoma. However, the role of PD-1 blockade in the treatment of undifferentiated and dedifferentiated endometrial carcinoma remains unclear, as very few patients with these cancer subtypes were included in the trials. In this case report, we present a patient with dMMR dedifferentiated endometrial carcinoma, treated with primary surgery to no gross residual disease, followed by carboplatin/paclitaxel chemotherapy and a short course of maintenance pembrolizumab. To date, the patient remains with a prolonged disease-free survival of 61 months, supporting the potential use of PD-1 inhibitors in the upfront treatment of unmeasurable, advanced-stage, dMMR dedifferentiated endometrial carcinoma.

Robotic-assisted uterine transposition followed by anatomic pelvic repositioning for a patient with intramural fibroids and rectal cancer.

OBJECTIVE: To report the first described case of robotic-assisted utero-ovarian transposition followed by anatomic repositioning in the pelvis and cervicovaginal anastomosis in a woman with uterine fibroids, which was performed for fertility preservation in the context of pelvic radiation for rectal cancer. DESIGN: Description of technique and live-action narrated surgical footage showing uterine transposition and repositioning. SETTING: University hospital. PATIENTS: A 36-year-old woman with a new diagnosis of cT3N2M0 rectal adenocarcinoma planned for neoadjuvant chemotherapy and pelvic radiation and desired fertility preservation permissive of future pregnancy. A transvaginal ultrasound revealed a 5-cm posterior leiomyoma and a normal endometrial cavity. The patient elected for utero-ovarian transposition before chemoradiation. The patient included in this video gave consent for publication and posting of the video online, including on social media, the journal website, scientific literature websites, and other applicable sites. Per institutional guidelines, an Institutional Review Board review was not required. INTERVENTIONS: Robotic-assisted utero-ovarian transposition was performed in an inpatient setting 2 weeks after ovarian stimulation and oocyte retrieval. She was given a gonadotropin-releasing hormone agonist for menstrual suppression after oocyte retrieval. The uterus and adnexa were transposed en bloc to the upper abdomen, with perfusion via retroflected infundibulopelvic ligaments. Intravenous indocyanine green was administered intraoperatively to visualize uterine perfusion. Three weeks postoperatively, the patient underwent surgical management of small bowel obstruction, which was successfully managed with laparoscopic adhesiolysis. The patient subsequently completed chemoradiation and had a complete response to the rectal tumor. She therefore elected for surveillance. Seven months after transposition and 2 months after completion of treatment, the patient underwent uncomplicated robotic-assisted utero-ovarian anatomic repositioning in the pelvis with cervicovaginal anastomosis. Chromopertubation confirmed tubal patency. MAIN OUTCOME MEASURES: Restoration of normal pelvic anatomy and resumption of reproductive physiology. RESULTS: At her 4-month postoperative visit, the cervix and vagina were normal in appearance. The patient reported the return of spontaneous menses and sexual activity without complications. CONCLUSION: This case is unique because of the presence of bulky intramural uterine fibroids. The described technique may be useful for selected cancer patients who desire to carry a pregnancy after pelvic radiation for cancer treatment, and demonstrates that patients considering utero-ovarian transposition need not be excluded solely on the basis of the presence of uterine fibroids.

Integrating Social Needs Screening and Resource Referral Into Standard Ambulatory Oncology Care: A Quality Improvement Project.

PURPOSE: We previously implemented paper-based screening for health-related social resource needs (HRSN) in our gynecologic oncology clinic and found that 36% of patients who completed the screening reported HRSN. We identified two primary deficiencies with our process. First, only 52% of patients completed the screening. Second, 37% of patients with needs failed to indicate if they desired resource referral or not. Therefore, we conducted a quality improvement project to integrate screening and referral processes into the electronic medical record (EMR) and routine clinic workflow to achieve at least 90% screening compliance and 90% elicited referral preference. METHODS: A multidisciplinary team consisting of physicians, a health outcomes researcher, a computer programmer, project assistants, and the staff of a partner community organization designed and implemented an intervention that screened for HRSN online via the EMR patient platform or in person during visits. The primary outcome was the percentage of eligible patients who completed the HRSN screening (ie, reach). Outcomes were reviewed weekly, and feedback was provided to stakeholders monthly. Iterative changes were incorporated into five successive Plan-Do-Study-Act (PDSA) cycles completed from January 2021 to March 2023. RESULTS: Screening compliance increased from the baseline of 52% (paper-based) to 97% in PDSA 4. Completion via the online patient portal increased from 17% in prelaunch to 49% in PDSA 4. Of patients who reported needs, 100% had a documented referral preference. CONCLUSION: Compared with paper-based screening, an EMR-integrated HRSN screening and referral system significantly improved reach to patients at a gynecologic oncology clinic. Implementation efforts to expand to other ambulatory clinic settings are in process.

Salpingectomy for the Primary Prevention of Ovarian Cancer: A Systematic Review.

Importance: Most ovarian cancers originate in the fimbriated end of the fallopian tube. This has led to the hypothesis that surgical resection of the fallopian tubes at the time of gynecologic and nongynecologic surgical procedures-referred to as an opportunistic salpingectomy-may prevent the development of epithelial ovarian cancer for women at an average risk of developing the disease. Objective: To compile a comprehensive, state-of-the-science review examining the current landscape of performing bilateral salpingectomy for ovarian cancer prevention. Evidence Review: A systematic review of the literature was performed on March 4, 2022, to identify studies examining salpingectomy for ovarian cancer prevention. This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 statement. Four databases were selected: PubMed via the National Library of Medicine's PubMed.gov, Embase via Elsevier's Embase.com, Cochrane Central Register of Controlled Trials (CENTRAL) via Wiley's Cochrane Library, and Northern Light Life Sciences Conference Abstracts via Ovid. A total of 20 gray literature sources, including 1 database, 2 registers, 1 repository, 1 index, 1 archive, 1 preprint server, 1 agency, and 12 organizations, were also searched. Findings: The initial search produced 1089 results; a total of 158 publications were included in the final review. Salpingectomy has been associated with ovarian cancer risk reduction of approximately 80%. Studies have demonstrated that salpingectomy was safe, cost-effective, and was not associated with an earlier age of menopause onset. With widespread implementation, salpingectomy has the potential to reduce ovarian cancer mortality in the US by an estimated 15%. Both physician and patient awareness regarding the adnexa as the origin for most ovarian cancers, as well as the existence of salpingectomy and its potential benefits in reducing ovarian cancer risk, has increased during the past decade. Raising awareness and developing effective implementation strategies are essential. Conclusions and Relevance: The results of this systematic review suggest that bilateral salpingectomy for ovarian cancer prevention was safe and feasible and has the potential to be a cost-effective and cost-saving strategy across the population. Prospective studies to demonstrate long-term survival outcomes and feasibility in nongynecologic surgical procedures are warranted.

Successful Treatment of Paraneoplastic Neuropathy and Pruritis With Scrambler Therapy: A Case Report.

Paraneoplastic neuropathy, including pruritis, remains a vexing problem as it often does not resolve even with successful treatment of cancer. Scrambler Therapy is a superficial form of neuromodulation that replaces the pain signal with "non-pain information" that is approved for chronic and neuropathic pain, with few side effects. We report here two cases of paraneoplastic neuropathy, one with additional pruritis, that both responded satisfactorily to Scrambler Therapy with no side effects.

Optimizing Perioperative Venous Thromboembolism Chemoprophylaxis on a Gynecologic Oncology Service.

BACKGROUND: Perioperative venous thromboembolism (VTE) is a significant cause of morbidity and mortality after gynecologic cancer surgery. Here we report a quality improvement intervention to increase perioperative VTE chemoprophylaxis compliance. STUDY DESIGN: All operations performed by a gynecologic oncologist at a tertiary urban university medical center admitted to the hospital for at least one midnight were included. Using a pre/post design with a washout period, we sought to increase perioperative VTE chemoprophylaxis compliance from 22% in the historical control (HC) cohort to 90% in the quality improvement (QI) cohort. The perioperative VTE chemoprophylaxis process was standardized by addressing four domains: preoperative VTE chemoprophylaxis, surgical time-out, postoperative VTE chemoprophylaxis, and intervention education and compliance tracking. Pearson's chi-square test was used to compare HC vs QI cohort compliance. RESULTS: There were 130 surgical cases in the HC cohort and 131 in the QI cohort. Forty-two percent underwent laparotomy, and 57% had cancer at the time of operation. VTE chemoprophylaxis compliance improved from 22% in the HC cohort to 82% in the QI cohort (p < 0.001). Preoperative VTE chemoprophylaxis compliance improved from 76% in the HC cohort to 94% in the QI cohort (p < 0.001), and postoperative VTE chemoprophylaxis compliance improved from 27% to 87% (p < 0.001). Thirty-day postoperative VTE occurred in three patients (2%) in the HC cohort and none in the QI cohort (p = 0.08). CONCLUSIONS: A low-cost and low-technology QI initiative intervention improved perioperative compliance with VTE chemoprophylaxis.

Gynecologic oncology HPV vaccination practice patterns: Investigating practice barriers, knowledge gaps and opportunities for maximizing cervical cancer prevention.

Objective: HPV vaccination is an important form of cancer prevention. Gynecologic oncologists have an opportunity to improve adult vaccination rates. We aimed to describe current HPV vaccination practices and barriers to vaccination reported by gynecologic oncologists. Methods: An online survey was developed, pilot tested and sent to U.S. members of the Society of Gynecologic Oncology. Results: Of the 226 respondents, most were female (73%), < 45 years old (64%) and practiced in urban (60%) and academic settings (69%). Ninety percent had recommended the HPV vaccine in the past year. Nearly half (47%) had facilitated vaccination by: administering the HPV vaccine in clinic (40%), stocking the vaccine (35%), or prescribing the vaccine (30%). Recommending the vaccine was associated with higher outpatient volume, practicing in the South vs. Northeast, and having higher levels of vaccine knowledge.Of the 90% who recommended the vaccine, 60% did not prescribe or know if they could prescribe the vaccine in their state. Prioritization of cancer treatment was the most commonly reported barrier to HPV vaccination (88%). Approximately half of providers reported other systems-level hinderances such as high cost of stocking the vaccine, clinic flow disruption, or uncertainty surrounding insurance coverage. Almost all recommenders offered the vaccine at HPV-related dysplasia (92%) or cancer (80%) visits, while only 24-50% offered it at non-HPV-related visits. Conclusions: These survey results identify patient, provider, and systems-level barriers that could be targeted to help increase adult HPV vaccination in gynecologic oncology clinics.

Patients' and oncologists' preferences for second-line maintenance PARP inhibitor therapy in epithelial ovarian cancer.

Aim: To understand the preferences of US patients and oncologists for PARP inhibitors as second-line maintenance (2LM) for epithelial ovarian cancer. Methods: A discrete choice experiment was conducted to assess the preferences of treatment attributes. Results: The most valued attributes were risk of grade 3/4 adverse events (AEs; patients, n = 204) and progression-free survival (PFS; oncologists, n = 151). To accept a 37% increased risk of grade 3/4 AEs, PFS would need to increase by 27.9 months (patients) and 6.3 months (oncologists). The least valued attributes were dosing form/frequency (patients) and grade 3/4 anemia risk (oncologists). Conclusion: Patients' and oncologists' willingness to make benefit-risk trade-offs in the 2LM setting suggests that the PFS gains observed in selected studies of poly (ADP-ribose) polymerase inhibitors in BRCA-mutated disease are worth the toxicity risk.

Plain language summary Maintenance therapy is a treatment option intended to keep ovarian cancer from coming back or getting worse for as long as possible after responding to chemotherapy. PARP inhibitors are a new type of maintenance therapy for ovarian cancer. This study aimed to understand the patients' and physicians' preferences for the benefits and risks associated with different PARP inhibitors used as maintenance therapy for ovarian cancer. Participants were asked to compare various treatment options based on their different safety profiles, effectiveness and form of medication (e.g., three capsules by mouth once a day versus two tablets by mouth twice a day), and then choose the treatment they most preferred. Through this exercise, the treatment features that mattered most to patients and physicians were identified. The most important treatment feature for patients was decreasing the chance of experiencing a serious side effect that requires medical intervention or hospitalization. In contrast, physicians valued lengthening the time that a cancer remains stable and does not worsen. To accept a 37% higher chance of experiencing a side effect that requires medical intervention or hospitalization, patients expect their cancer to remain stable and not worsen for an additional 28 months. This was a large difference from the 6 months that the physicians would consider as acceptable. The least important treatment features for patients are the amount of pills required per dose, the form of the given medication (e.g., tablet vs capsule) and the schedule of taking the treatment. On the other hand, physicians were least concerned about lowering the risk of experiencing low blood counts that, requiring medical intervention.

Adjuvant treatment improves overall survival in women with high-intermediate risk early-stage endometrial cancer with lymphovascular space invasion.

BACKGROUND: Adjuvant therapy in early-stage endometrial cancer has not shown a clear overall survival benefit, and hence, patient selection remains crucial. OBJECTIVE: To determine whether women with high-intermediate risk, early-stage endometrial cancer with lymphovascular space invasion particularly benefit from adjuvant treatment in improving oncologic outcomes. METHODS: A multi-center retrospective study was conducted in women with stage IA, IB, and II endometrial cancer with lymphovascular space invasion who met criteria for high-intermediate risk by Gynecologic Oncology Group (GOG) 99. Patients were stratified by the type of adjuvant treatment received. Clinical and pathologic features were abstracted. Progression-free and overall survival were evaluated using multivariable analysis. RESULTS: 405 patients were included with the median age of 67 years (range 27-92, IQR 59-73). 75.0% of the patients had full staging with lymphadenectomy, and 8.6% had sentinel lymph node biopsy (total 83.6%). After surgery, 24.9% of the patients underwent observation and 75.1% received adjuvant therapy, which included external beam radiation therapy (15.1%), vaginal brachytherapy (45.4%), and combined brachytherapy + chemotherapy (19.1%). Overall, adjuvant treatment resulted in improved oncologic outcomes for both 5-year progression-free survival (77.2% vs 69.6%, HR 0.55, p=0.01) and overall survival (81.5% vs 60.2%, HR 0.42, p<0.001). After adjusting for stage, grade 2/3, and age, improved progression-free survival and overall survival were observed for the following adjuvant subgroups compared with observation: external beam radiation (overall survival HR 0.47, p=0.047, progression-free survival not significant), vaginal brachytherapy (overall survival HR 0.35, p<0.001; progression-free survival HR 0.42, p=0.003), and brachytherapy + chemotherapy (overall survival HR 0.30 p=0.002; progression-free survival HR 0.35, p=0.006). Compared with vaginal brachytherapy alone, external beam radiation or the addition of chemotherapy did not further improve progression-free survival (p=0.80, p=0.65, respectively) or overall survival (p=0.47, p=0.74, respectively). CONCLUSION: Adjuvant therapy improves both progression-free survival and overall survival in women with early-stage endometrial cancer meeting high-intermediate risk criteria with lymphovascular space invasion. External beam radiation or adding chemotherapy did not confer additional survival advantage compared with vaginal brachytherapy alone.

Human epidermal growth factor 2 (HER2) in early stage uterine serous carcinoma: A multi-institutional cohort study.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) has emerged as an important prognostic and therapeutic target in advanced stage and recurrent uterine serous carcinoma (USC). The significance of tumoral HER2 expression in early-stage disease has not been established. METHODS: This multi-center cohort study included women with stage I USC treated from 2000 to 2019. Demographic, treatment, recurrence, and survival data were collected. Immunohistochemistry (IHC) was performed for HER2 and scored 0-3+. Equivocal IHC results (2+) were further tested with fluorescence in-situ hybridization (FISH). HER2 positivity was defined as 3+ IHC or FISH positive. RESULTS: One hundred sixty-nine patients with stage I USC were tested for HER2; 26% were HER2-positive. There were no significant differences in age, race, stage, adjuvant therapy, or follow-up duration between the HER2-positive and negative cohorts. Presence of lymph-vascular space invasion was correlated with HER2-positive tumors (p = .003). After a median follow-up of 50 months, there were 43 (25.4%) recurrences. There were significantly more recurrences in the HER2-positive cohort (50.0% vs 16.8%, p < .001). HER2 positive tumors were associated with worse progression-free (PFS) and overall survival (OS) (p < .001 and p = .024). On multivariate analysis, HER2 positive tumors were associated with inferior PFS (aHR 3.50, 95%CI 1.84-6.67; p < .001) and OS (aHR 2.00, 95%CI 1.04-3.88; p = .039) compared to HER2-negative tumors. CONCLUSIONS: Given its significant association with worse recurrence and survival outcomes, HER2 positivity appears to be a prognostic biomarker in women with stage I uterine serous carcinoma. These data provide support for clinical trials with anti-HER2-directed therapy in early-stage disease.

Basic social resource needs screening in the gynecologic oncology clinic: a quality improvement initiative.

BACKGROUND: Social determinants of health are known to contribute to disparities in health outcomes. Routine screening for basic social needs is not a part of standard care; however, the association of those needs with increased healthcare utilization and poor compliance with guideline-directed care is well established. OBJECTIVE: In this study, we aimed to assess the prevalence of basic social resource needs identified through a quality improvement initiative in a gynecologic oncology outpatient clinic. In addition, we aimed to identify clinical and demographic factors associated with having basic social resource needs. STUDY DESIGN: We performed a prospective cohort study of women presenting to a gynecologic oncology clinic at an urban academic institution who were screened for basic social resource needs as part of a quality improvement initiative from July 2017 to May 2018. The following 8 domains of resource needs were assessed: food insecurity, housing insecurity, utility needs, financial strain, transportation, childcare, household items, and difficulty reading hospital materials. Women with needs were referred to resources to address those needs. Demographic and clinical information were collected for each patient. The prevalence of needs and successful follow-up interventions were calculated. Patient factors independently associated with having at least 1 basic social resource need were identified using multivariable Poisson regression. RESULTS: A total of 752 women were screened in the study period, of whom 274 (36%) reported 1 or more basic social resource need, with a median of 1 (range, 1-7) need. Financial strain was the most commonly reported need (171 of 752, 23%), followed by transportation (119 of 752, 16%), difficulty reading hospital materials (54 of 752, 7%), housing insecurity (31 of 752, 4%), food insecurity (28 of 752, 4%), household items (22 of 752, 3%), childcare (15 of 752, 2%), and utility needs (13 of 752, 2%). On multivariable analysis, independent factors associated with having at least 1 basic social resource need were being single, divorced or widowed, nonwhite race, current smoker, nonprivate insurance, and a history of anxiety or depression. A total of 36 of 274 (13%) women who screened positive requested assistance and were referred to resources to address those needs. Of the 36 women, 25 (69%) successfully accessed a resource or felt equipped to address their needs, 9 (25%) could not be reached despite repeated attempts, and 2 (6%) declined assistance. CONCLUSION: Basic social resource needs are prevalent in women presenting to an urban academic gynecologic oncology clinic and can be identified and addressed through routine screening. To help mitigate ongoing disparities in this population, screening for and addressing basic social resource needs should be incorporated into routine comprehensive care in gynecologic oncology clinics.

The addition of metformin to progestin therapy in the fertility-sparing treatment of women with atypical hyperplasia/endometrial intraepithelial neoplasia or endometrial cancer: Little impact on response and low live-birth rates.

OBJECTIVE: Our objectives were 1) to compare the efficacy of progestin therapy combined with metformin (Prog-Met) to Prog alone as primary fertility sparing treatment in women with atypical hyperplasia/endometrial intraepithelial neoplasia (AH/EIN) or early-stage endometrioid carcinoma (EC), and 2) to analyze the proportion of women achieving live birth following treatment. METHODS: A retrospective cohort study of all reproductive-aged women with AH/IN or EC treated with Prog ± Met from 1999-2018 was conducted. Complete response (CR) was assessed and Kaplan-Meier analysis used to calculate time to CR. Comparison of potential response predictors was performed with multivariable Cox regression models. RESULTS: Ninety-two women met criteria; 59% (n = 54) were treated for AH/EIN and 41% (n = 38) for EC. Their median age, body mass index, and follow up time was 35 years, 37.7 kg/m2, and 28.4 months, respectively. Fifty-eight women (63%) received Prog and 34 (37%) received Prog-Met. Overall, 79% (n = 73) of subjects responded to treatment with a CR of 69% (n = 63). There was no difference in CR (p = 0.90) or time to CR (p = 0.31) between the treatment cohorts. Overall, 22% experienced a disease recurrence. On multivariable analysis, EC histology was the only covariate associated with a decreased Prog response (HR 0.48; p = 0.007). Only 17% of the cohort achieved a live-birth pregnancy, the majority of which required assisted reproductive technologies (81%) and occurred in the Prog treatment group. CONCLUSIONS: Our study does not support the use of Prog-Met therapy for treatment of AH/EIN or EC. Additionally, fewer than 20% of women achieved a live-birth pregnancy during the study period, with most requiring ART.

Adjuvant therapy for early stage, endometrial cancer with lymphovascular space invasion: Is there a role for chemotherapy?

OBJECTIVES: Lymphovascular space invasion (LVSI) is an independent risk factor for recurrence and poor survival in early-stage endometrioid endometrial cancer (EEC), but optimal adjuvant treatment is unknown. We aimed to compare the survival of women with early-stage EEC with LVSI treated postoperatively with observation (OBS), radiation (RAD, external beam and/or vaginal brachytherapy), or chemotherapy (CHEMO)+/-RAD. METHODS: This was a multi-institutional, retrospective cohort study of women with stage I or II EEC with LVSI who underwent hysterectomy+/-lymphadenectomy from 2005 to 2015 and received OBS, RAD, or CHEMO+/-RAD postoperatively. Progression-free survival and overall survival were evaluated using Kaplan-Meier estimates and Cox proportional hazards models. RESULTS: In total, 478 women were included; median age was 64 years, median follow-up was 50.3 months. After surgery, 143 (30%) underwent OBS, 232 (48.5%) received RAD, and 103(21.5%) received CHEMO+/-RAD (95% of whom received RAD). Demographics were similar among groups, but those undergoing OBS had lower stage and grade. A total of 101 (21%) women recurred. Progression-free survival (PFS) was improved in both CHEMO+/-RAD (HR = 0.18, 95% CI: 0.09-0.39) and RAD (HR = 0.31, 95% CI: 0.18-0.54) groups compared to OBS, though neither adjuvant therapy was superior to the other. However, in grade 3 tumors, the CHEMO+/-RAD group had superior PFS compared to both RAD (HR 0.25; 95% CI: 0.12-0.52) and OBS cohorts (HR = 0.10, 95% CI: 0.03-0.32). Overall survival did not differ by treatment. CONCLUSIONS: In early-stage EEC with LVSI, adjuvant therapy improved PFS compared to observation alone. In those with grade 3 EEC, adjuvant chemotherapy with or without radiation improved PFS compared to observation or radiation alone.