Top advances of the year: Uterine cancer.

Endometrial cancer continues to be the only gynecologic malignancy with a rising incidence and mortality, with both regional and global implications. Combination carboplatin and paclitaxel has been the recognized chemotherapy backbone for the treatment of advanced-stage or recurrent disease, with modest clinical outcomes. Over the last year, significant advances were achieved in improving oncologic outcomes by capitalizing on the molecular characterization of this heterogenous disease. These advances include incorporation of immunotherapy, identification of effective hormonal approaches, the evolution of antibody drug conjugates, and utilization of alternate targeted therapies. PLAIN LANGUAGE SUMMARY: The molecular characterization of endometrial cancer has been critical in informing novel treatment strategies. Over the past year, significant gains have been made via the incorporation of immunotherapy, hormonal combinations as well as antibody drug conjugates.

NRG-GY012: Randomized phase 2 study comparing olaparib, cediranib, and the combination of cediranib/olaparib in women with recurrent, persistent, or metastatic endometrial cancer.

PURPOSE: This paper reports the efficacy of the poly (ADP-ribose) polymerase inhibitor olaparib alone and in combination with the antiangiogenesis agent cediranib compared with cediranib alone in patients with advanced endometrial cancer. METHODS: This was open-label, randomized, phase 2 trial (NCT03660826). Eligible patients had recurrent endometrial cancer, received at least one (<3) prior lines of chemotherapy, and were Eastern Cooperative Oncology Group performance status 0 to 2. Patients were randomly assigned (1:1:1), stratified by histology (serous vs. other) to receive cediranib alone (reference arm), olaparib, or olaparib and cediranib for 28-day cycles until progression or unacceptable toxicity. The primary end point was progression-free survival in the intention-to-treat population. Homologous repair deficiency was explored using the BROCA-GO sequencing panel. RESULTS: A total of 120 patients were enrolled and all were included in the intention-to-treat analysis. Median age was 66 (range, 41-86) years and 47 (39.2%) had serous histology. Median progression-free survival for cediranib was 3.8 months compared with 2.0 months for olaparib (hazard ratio, 1.45 [95% CI, 0.91-2.3] p = .935) and 5.5 months for olaparib/cediranib (hazard ratio, 0.7 [95% CI, 0.43-1.14] p = .064). Four patients receiving the combination had a durable response lasting more than 20 months. The most common grade 3/4 toxicities were hypertension in the cediranib (36%) and olaparib/cediranib (33%) arms, fatigue (20.5% olaparib/cediranib), and diarrhea (17.9% cediranib). The BROCA-GO panel results were not associated with response. CONCLUSION: The combination of cediranib and olaparib demonstrated modest clinical efficacy; however, the primary end point of the study was not met. The combination was safe without unexpected toxicity.

A tale of two pathways: Review of immune checkpoint inhibitors in DNA mismatch repair-deficient and microsatellite instability-high endometrial cancers.

The DNA mismatch repair (MMR) pathway is critical for correcting DNA mismatches generated during DNA replication. MMR-deficiency (MMR-D) leads to microsatellite instability (MSI) associated with an increased mutation rate, driving cancer development. This is particularly relevant in endometrial cancer (EC) as 25%-30% of tumors are of MMR-D/MSI-high (MSI-H) phenotype. Comprehensive assessment using immunohistochemistry (IHC) and sequencing-based techniques are necessary to fully evaluate ECs given the importance of molecular subtyping in staging and prognosis. This also influences treatment selection as clinical trials have demonstrated survival benefits for immune checkpoint inhibitors (ICIs) alone and in combination with chemotherapy for MMR-D/MSI-H EC patients in various treatment settings. As a portion of MMR-D/MSI-H ECs are driven by Lynch syndrome, an inherited cancer predisposition syndrome that is also associated with colorectal cancer, this molecular subtype also prompts germline assessment that can affect at-risk family members. Additionally, heterogeneity in the tumor immune microenvironment and tumor mutation burden (TMB) have been described by MMR mechanism, meaning MLH1 promoter hypermethylation versus germline/somatic MMR gene mutation, and this may affect response to ICI therapies. Variations by ancestry in prevalence and mechanism of MMR-D/MSI-H tumors have also been reported and may influence health disparities given observed differences in tumors of Black compared to White patients which may affect ICI eligibility. These observations highlight the need for additional prospective studies to evaluate the nuances regarding MMR-D heterogeneity as well as markers of resistance to inform future trials of combination therapies to further improve outcomes for patients with EC.

TSLP enhances progestin response in endometrial cancer via androgen receptor signal pathway.

BACKGROUND: The enriched proteins within in vitro fertilisation (IVF)-generated human embryonic microenvironment could reverse progestin resistance in endometrial cancer (EC). METHODS: The expression of thymic stromal lymphopoietin (TSLP) in EC was evaluated by immunoblot and IHC analysis. Transcriptome sequencing screened out the downstream pathway regulated by TSLP. The role of TSLP, androgen receptor (AR) and KANK1 in regulating the sensitivity of EC to progestin was verified through a series of in vitro and in vivo experiments. RESULTS: TSLP facilitates the formation of a BMP4/BMP7 heterodimer, resulting in activation of Smad5, augmenting AR signalling. AR in turn sensitises EC cells to progestin via KANK1. Downregulation of TSLP, loss of AR and KANK1 in EC patients are associated with tumour malignant progress. Moreover, exogenous TSLP could rescue the anti-tumour effect of progestin on mouse in vivo xenograft tumour. CONCLUSIONS: Our findings suggest that TSLP enhances the sensitivity of EC to progestin through the BMP4/Smad5/AR/KANK1 axis, and provide a link between embryo development and cancer progress, paving the way for the establishment of novel strategy overcoming progestin resistance using embryo original factors.

Adding immunotherapy to first-line treatment of advanced and metastatic endometrial cancer.

BACKGROUND: Immunotherapy has transformed the endometrial cancer treatment landscape, particularly for those exhibiting mismatch repair deficiency [MMRd/microsatellite instability-hypermutated (MSI-H)]. A growing body of evidence supports the integration of immunotherapy with chemotherapy as a first-line treatment strategy. Recently, findings from ongoing trials such as RUBY (NCT03981796), NRG-GY018 (NCT03914612), AtTEnd (NCT03603184), and DUO-E (NCT04269200) have been disclosed. MATERIALS AND METHODS: This paper constitutes a review and meta-analysis of phase III trials investigating the role of immunotherapy in the first-line setting for advanced or recurrent endometrial cancer. RESULTS: The pooled data from 2320 patients across these trials substantiate the adoption of chemotherapy alongside immunotherapy, revealing a significant improvement in progression-free survival compared to chemotherapy alone [hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.62-0.79] across all patient groups. Progression-free survival benefits are more pronounced in MMRd/MSI-H tumors (n = 563; HR 0.33, 95% CI 0.23-0.43). This benefit, albeit less robust, persists in the MMR-proficient/microsatellite stable group (n = 1757; HR 0.74, 95% CI 0.60-0.91). Pooled data further indicate that chemotherapy plus immunotherapy enhances overall survival compared to chemotherapy alone in all patients (HR 0.75, 95% CI 0.63-0.89). However, overall survival data maturity remains low. CONCLUSIONS: The incorporation of immunotherapy into the initial treatment for advanced and metastatic endometrial cancer brings about a substantial improvement in oncologic outcomes, especially within the MMRd/MSI-H subset. This specific subgroup is currently a focal point of investigation for evaluating the potential of chemotherapy-free regimens. Ongoing exploratory analyses aim to identify non-responding patients eligible for inclusion in clinical trials.

MITO END-3: efficacy of avelumab immunotherapy according to molecular profiling in first-line endometrial cancer therapy.

BACKGROUND: Immunotherapy combined with chemotherapy significantly improves progression-free survival (PFS) compared to first-line chemotherapy alone in advanced endometrial cancer (EC), with a much larger effect size in microsatellite instability-high (MSI-H) cases. New biomarkers might help to select patients who may have benefit among those with a microsatellite-stable (MSS) tumor. PATIENTS AND METHODS: In a pre-planned translational analysis of the MITO END-3 trial, we assessed the significance of genomic abnormalities in patients randomized to standard carboplatin/paclitaxel without or with avelumab. RESULTS: Out of 125 randomized patients, 109 had samples eligible for next-generation sequencing analysis, and 102 had MSI tested. According to The Cancer Genome Atlas (TCGA), there were 29 cases with MSI-H, 26 with MSS TP53 wild type (wt), 47 with MSS TP53 mutated (mut), and 1 case with POLE mutation. Four mutated genes were present in >30% of cases: TP53, PIK3CA, ARID1A, and PTEN. Eleven patients (10%) had a BRCA1/2 mutation (five in MSI-H and six in MSS). High tumor mutational burden (≥10 muts/Mb) was observed in all MSI-H patients, in 4 out of 47 MSS/TP53 mut, and no case in the MSS/TP53 wt category. The effect of avelumab on PFS significantly varied according to TCGA categories, being favorable in MSI-H and worst in MSS/TP53 mut (P interaction = 0.003); a similar non-significant trend was seen in survival analysis. ARID1A and PTEN also showed a statistically significant interaction with treatment effect, which was better in the presence of the mutation (ARID1A P interaction = 0.01; PTEN P interaction = 0.002). CONCLUSION: The MITO END-3 trial results suggest that TP53 mutation is associated with a poor effect of avelumab, while mutations of PTEN and ARID1A are related to a positive effect of the drug in patients with advanced EC.

Overall survival in patients with endometrial cancer treated with dostarlimab plus carboplatin-paclitaxel in the randomized ENGOT-EN6/GOG-3031/RUBY trial.

BACKGROUND: Part 1 of the RUBY trial (NCT03981796) evaluated dostarlimab plus carboplatin-paclitaxel compared with placebo plus carboplatin-paclitaxel in patients with primary advanced or recurrent endometrial cancer (EC). At the first interim analysis, the trial met one of its dual primary endpoints with statistically significant progression-free survival benefits in the mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) and overall populations. Overall survival (OS) results are reported from the second interim analysis. PATIENTS AND METHODS: RUBY is a phase III, global, double-blind, randomized, placebo-controlled trial. Part 1 of RUBY enrolled eligible patients with primary advanced stage III or IV or first recurrent EC who were randomly assigned (1 : 1) to receive either dostarlimab (500 mg) or placebo, plus carboplatin-paclitaxel every 3 weeks for 6 cycles followed by dostarlimab (1000 mg) or placebo every 6 weeks for up to 3 years. OS was a dual primary endpoint. RESULTS: A total of 494 patients were randomized (245 in the dostarlimab arm; 249 in the placebo arm). In the overall population, with 51% maturity, RUBY met the dual primary endpoint for OS at this second interim analysis, with a statistically significant reduction in the risk of death [hazard ratio (HR) = 0.69, 95% confidence interval (CI) 0.54-0.89, P = 0.0020] in patients treated with dostarlimab plus carboplatin-paclitaxel versus carboplatin-paclitaxel alone. The risk of death was lower in the dMMR/MSI-H population (HR = 0.32, 95% CI 0.17-0.63, nominal P = 0.0002) and a trend in favor of dostarlimab was seen in the mismatch repair-proficient/microsatellite stable population (HR = 0.79, 95% CI 0.60-1.04, nominal P = 0.0493). The safety profile for dostarlimab plus carboplatin-paclitaxel was consistent with the first interim analysis. CONCLUSIONS: Dostarlimab in combination with carboplatin-paclitaxel demonstrated a statistically significant and clinically meaningful OS benefit in the overall population of patients with primary advanced or recurrent EC while demonstrating an acceptable safety profile.

RING1 Inhibition Has a Cell-Specific Antitumoral Role by Promoting Autophagy in Endometrial Cancer Cells.

BACKGROUND/AIMS: Factors influencing gene expression through chemical modifications of histones may play an important role in the regulation of the autophagy process in cancers. RING1A or RING1B are responsible for the catalytical activity of Polycomb repressive complex 1 (PRC1) which monoubiquitylate histone H2A. The aim of the study was to determine the effect of the RING1A/B protein inhibition on the autophagy process in endometrial cancer cells and the anticancer effectiveness of RING1 inhibitor PRT4165 in combination with autophagy inhibitors. METHODS: The expression of autophagy genes and proteins were analyzed in endometrial cancer cells HEC-1A and Ishikawa grown in different glucose concentrations and treated with PRT4165. To assess the effectiveness of PRT4165 used alone or in combination with HCQ or Lys05, IC50 and the combination index (CI) were calculated. Flow cytometry method was used to estimate apoptotic cells after treatment. RESULTS: The results confirm the impact of RINGs on autophagy and apoptosis in endometrial cancer cells. PRT4165 inhibitor causes changes in the expression of ATG genes and autophagy markers and the effect depends on glucose concentration and cell types. However, the anticancer effectiveness of PRT4165 was lower when it was used in combination with autophagy inhibitors, suggesting that such a combination is not a promising anticancer strategy. CONCLUSION: The results indicate the importance of the RINGs in the process of autophagy and apoptosis. Further potentially more effective combinations of PRT4165 with autophagy modulators should be sought.

Prediction of complete regression in fertility-sparing patients with endometrial cancer and apical hyperplasia: the GLOBAL model in a large Chinese cohort.

BACKGROUND: Fertility preservation treatment is increasingly essential for patients with apical endometrial hyperplasia (AEH) and early endometrial cancer (EEC) worldwide. Complete regression (CR) is the main endpoint of this treatment. Accurately predicting CR and implementing appropriate interventions during treatment are crucial for these patients. METHODS: We conducted a retrospective study involving 193 patients diagnosed with atypical AEH or EEC, enrolled from January 2012 to March 2022 at our center. We evaluated 24 clinical parameters as candidate predictors and employed LASSO regression to develop a prediction model for CR. Subsequently, a nomogram was constructed to predict CR after the treatment. We evaluated the performance of the nomogram using receiver operator characteristic (ROC) curve and decision curve analysis (DCA) to assess its predictive accuracy. Additionally, we employed cumulative curves to determine the CR rate among patients. RESULTS: Out of the 193 patients, 173 achieved CR after undergoing fertility preservation treatment. We categorized features with similar properties and provided a list of formulas based on their coefficients. The final model, named GLOBAL (including basic information, characteristics, blood pressure, glucose metabolism, lipid metabolism, immunohistochemistry, histological type, and medication), comprised eight variables identified using LASSO regression. A nomogram incorporating these eight risk factors was developed to predict CR. The GLOBAL model exhibited an AUC of 0.907 (95% CI 0.828-0.969). Calibration plots demonstrated a favorable agreement between the predicted probability by the GLOBAL model and actual observations in the cohort. The cumulative curve analysis revealed varying cumulative CR rates among patients in the eight subgroups. Categorized analysis demonstrated significant diversity in the effects of the GLOBAL model on CR among patients with different total points (p < 0.05). CONCLUSION: We have developed and validated a model that significantly enhances the predictive accuracy of CR in AEH and EEC patients seeking fertility preservation treatment.

ENDOLUNG trial. A phase 1/2 study of the Akt/mTOR inhibitor and autophagy inducer Ibrilatazar (ABTL0812) in combination with paclitaxel/carboplatin in patients with advanced/recurrent endometrial cancer.

BACKGROUND: Carboplatin and paclitaxel (CP) have been the standard of care for advanced/recurrent endometrial cancer (EC) for many years. However, this chemotherapy combination shows limited efficacy and recurrences often occur in less than 12 months. ABTL0812 is a novel drug that selectively kill cancer cells by cytotoxic autophagy and has shown anticancer efficacy in preclinical models of EC in combination with CP. METHODS: ENDOLUNG was an open-label, phase 1/2 clinical trial designed to determine the safety and efficacy of Ibrilatazar (ABTL0812) with CP in patients with advanced/recurrent EC and non-irradiable stage III and IV squamous non-small cell lung cancer (sq-NSCLC). The phase 1 part consisted of a 3 + 3 de-escalation design followed by an expansion cohort with 12 patients. The primary endpoint was safety. ABTL0812 starting dose was 1300 mg tid combined with carboplatin at area under the curve (AUC) 5 and paclitaxel at 175 mg/m2 both administered every 21 days for up to 8 cycles. The phase 2 part included a total of 51 patients. The primary endpoint was overall response rate (ORR) and the secondary endpoints included duration of response (DOR), progression-free survival (PFS) and overall survival (OS). RESULTS: During the phase 1 only one dose limiting toxicity (DLT), a grade 4 neutropenia, was observed in 1 out of 6 patients, thus no de-escalation was applied. One additional DLT, a grade 3 febrile neutropenia, was observed in the expansion cohort, thus the recommended phase 2 dose (RP2D) for ABTL0812 was established at 1300 mg tid. Most frequent hematological adverse events (AE) of the combination were neutropenia (52.9%), anemia (37.3%) and thrombocytopenia (19.6%). Nausea (66.7%), asthenia (66.7%), diarrhea (54.9%) and vomiting (54.9%) were the most frequent non-hematological adverse events (AEs). The combination of ABTL0812 plus CP showed an ORR of 65.8% (13.2% complete response and 52.6% partial response) with a median DOR of 7.4 months (95% CI: 6.3-10.8 months). Median PFS was 9.8 months (95% CI: 6.6-10.6) and median OS 23.6 months (95% CI 6.4-ND). Pharmacokinetic parameters were compatible with target engagement observed in preclinical studies, and blood pharmacodynamic biomarkers indicated sustained target regulation during, at least, 28 days after starting the treatment. CONCLUSIONS: This study suggests that the combination of ABTL0812 with CP is safe and feasible with an encouraging activity in patients with advanced/recurrent EC. Our data warrant further confirmation in prospective randomized trials. TRIAL REGISTRATION: EU Clinical Trial Register, EudraCT number 2016-001352-21 and National Clinical Trials Number, NCT03366480. Registration on 19 September 2016.

Choosing the right adjuvant therapy for stage III-IVA endometrial cancer: A comparative analysis of chemoradiotherapy and chemotherapy.

OBJECTIVE: The optimal adjuvant treatment for patients with locally advanced endometrial cancer (EC) remains debatable. We comparatively analyzed recurrence patterns and survival outcomes in patients with stage III-IVA EC treated with adjuvant chemotherapy (CT) exclusively or combined with radiotherapy (CRT). METHODS: We retrospectively analyzed 184 patients treated for stage III-IVA EC at 2 tertiary institutions between 2010 and 2021. All patients underwent standard primary surgery and received either CT alone (n = 89) or CRT (n = 95) as an adjuvant treatment. We compared the failure patterns, recurrence-free survival (RFS), and overall survival (OS) between the CT and CRT groups. RESULTS: The median follow-up period was 54.8 months. Most patients underwent pelvic (94.6%) or para-aortic (75.5%) lymphadenectomies. The 5-year RFS was 69.2% with CRT versus 56.3% with CT (P = 0.038), and 5-year OS was 86.1% versus 78.9% (P = 0.357). Pelvic and para-aortic recurrence rates were significantly higher in the CT group (pelvic: 29.2%; para-aortic: 20.2%) than in the CRT group (pelvic: 10.5%; para-aortic: 6.3%). The CRT group showed a higher rate of distant recurrence (CRT, 23.2% vs. CT, 14.6%) however, the 5-year cumulative incidence of distant recurrence was not significantly different between the two groups (CRT, 28% vs. CT, 35%). CONCLUSIONS: This study highlights the potential benefits of adjuvant CRT in patients with stage III-IVA EC. The incorporation of molecular classification is necessary to derive optimal personalized adjuvant treatment strategies for this patient population.

Cost-effectiveness of lenvatinib plus pembrolizumab versus chemotherapy for recurrent mismatch repair-proficient endometrial cancer after platinum-based therapy.

OBJECTIVE: The recent Study 309-KEYNOTE-775 showed improved survival for lenvatinib plus pembrolizumab compared to chemotherapy in patients with recurrent endometrial cancer. We created a decision model to compare the cost-effectiveness of lenvatinib plus pembrolizumab in patients with recurrent mismatch repair-proficient (pMMR) endometrial cancer who had progressed after first-line chemotherapy. METHODS: A Markov model was created to simulate the clinical trajectory of 10,000 patients with recurrent pMMR endometrial cancer. The initial decision point in the model was treatment with ether lenvatinib plus pembrolizumab or chemotherapy (doxorubicin or dose-dense paclitaxel). Model probabilities, utility values and costs were derived with assumptions drawn from published literature. A cycle length of 3 months and a time horizon of 2 years was used. The effectiveness was calculated in terms of average quality adjusted life years (QALYs) gained. The primary outcome was incremental cost-effectiveness ratios (ICERs), expressed in 2020 US dollars/QALYs. One-way, two-way and probabilistic sensitivity analyses were performed. RESULTS: Chemotherapy was the least costly strategy at $66,693 followed by lenvatinib plus pembrolizumab ($193,590). Lenvatinib plus pembrolizumab resulted in more patients being alive at 2 years (lenvatinib plus pembrolizumab: 367, chemotherapy: 109). Chemotherapy was cost-effective compared with lenvatinib plus pembrolizumab (ICER: $164,493/QALYs). Lenvatinib plus pembrolizumab became cost-effective when its cost was reduced by $1553 per month (7.8% reduction). CONCLUSION: For patients with recurrent pMMR endometrial cancer Lenvatinib plus pembrolizumab is associated with greater survival but is more costly than chemotherapy. The cost of lenvatinib and pembrolizumab would have to be reduced by approximately 7% to be considered cost-effective.

Long-term follow-up of efficacy and safety of selinexor maintenance treatment in patients with TP53wt advanced or recurrent endometrial cancer: A subgroup analysis of the ENGOT-EN5/GOG-3055/SIENDO study.

OBJECTIVE: To report long-term efficacy and safety of selinexor maintenance therapy in adults with TP53 wild-type (TP53wt) stage IV or recurrent endometrial cancer (EC) who achieved partial remission (PR) or complete remission (CR) following chemotherapy. METHODS: Analysis of the prespecified, exploratory subgroup of patients with TP53wt EC from the phase 3 SIENDO study was performed. Progression-free survival (PFS) benefit in patients with TP53wt EC and across other patient subgroups were exploratory endpoints. Safety and tolerability were also assessed. RESULTS: Of the 263 patients enrolled in the SIENDO trial, 113 patients had TP53wt EC; 70/113 (61.9%) had TP53wt/proficient mismatch repair (pMMR) EC, and 29/113 (25.7%) had TP53wt/deficient mismatch repair (dMMR) EC. As of April 1, 2024, the median PFS (mPFS) for TP53wt patients who received selinexor compared with placebo was 28.4 versus 5.2 months (36.8-month follow-up, HR 0.44; 95% CI 0.27-0.73). A benefit in mPFS was seen with selinexor versus placebo regardless of MMR status (patients with TP53wt/pMMR EC: 39.5 vs 4.9 months, HR 0.36; 95% CI 0.19-0.71; patients with TP53wt/dMMR EC: 13.1 vs 3.7 months, HR 0.49; 95% CI 0.18-1.34). Selinexor treatment was generally manageable, with no new safety signals identified. CONCLUSION: In the phase 3 SIENDO study, selinexor maintenance therapy showed a promising efficacy signal and a manageable safety profile in the prespecified subgroup of patients with TP53wt EC who achieved a PR or CR following chemotherapy. These results are being further evaluated in an ongoing randomized phase 3 trial (NCT05611931).

A phase 2 trial of zanidatamab in HER2-overexpressed advanced endometrial carcinoma and carcinosarcoma (ZW25-IST-2).

OBJECTIVE: HER2 overexpression is associated with decreased overall survival in metastatic endometrial cancer. Trastuzumab with chemotherapy has demonstrated efficacy for first-line management of advanced HER2+ endometrial carcinoma, but HER2-directed therapy in the recurrent setting is limited. Zanidatamab (ZW25), a humanized, bispecific antibody that simultaneously binds the 2 distinct HER2 epitopes bound by trastuzumab and pertuzumab, has demonstrated safety and activity in HER2+ tumors. Here, we report the results of a phase 2, open-label study evaluating the efficacy and safety of zanidatamab in patients with HER2+ metastatic endometrial carcinoma/carcinosarcoma who received prior treatment. METHODS: We enrolled 16 patients with HER2+ endometrial carcinoma/carcinosarcoma after progression on ≤2 lines of therapy on a single-arm phase 2 study of zanidatamab. The primary endpoint was overall response rate (ORR; complete or partial response) by Response Evaluation Criteria in Solid Tumors version 1.1. HER2 immunohistochemistry and fluorescence in situ hybridization (FISH) were performed on pretreatment samples. Intratumor HER2 genetic heterogeneity was assessed. RESULTS: This study did not meet its primary efficacy endpoint. Although a clinical benefit rate of 37.5% was observed by 24 weeks, only 1 patient achieved a partial response (ORR, 6.2%). Eight patients had HER2 intratumor heterogeneity or lacked HER2 amplification by FISH. Decreased HER2 expression on repeat pretreatment samples was observed in 3 (75%) of 4 patients evaluated. CONCLUSIONS: We observed a low response rate to zanidatamab in recurrent HER2+ endometrial carcinoma/carcinosarcoma, which may be driven by downregulation of HER2 expression. Repeat HER2 testing should be considered prior to second-line HER2-directed therapy. CLINICALTRIALS: govidentifier: NCT04513665.

Intermittent energy restriction inhibits tumor growth and enhances paclitaxel response in a transgenic mouse model of endometrial cancer.

OBJECTIVE: Overweight/obesity is the strongest risk factor for endometrial cancer (EC), and weight management can reduce that risk and improve survival. We aimed to establish the differential benefits of intermittent energy restriction (IER) and low-fat diet (LFD), alone and in combination with paclitaxel, to reverse the procancer effects of high-fat diet (HFD)-induced obesity in a mouse model of EC. METHODS: Lkb1fl/flp53fl/fl mice were fed HFD or LFD to generate obese and lean phenotypes, respectively. Obese mice were maintained on a HFD or switched to a LFD (HFD-LFD) or IER (HFD-IER). Ten weeks after induction of endometrial cancer, mice in each group received paclitaxel or placebo for 4 weeks. Body and tumor weights; tumoral transcriptomic, metabolomic and oxylipin profiles; and serum metabolic hormones and chemocytokines were assessed. RESULTS: HFD-IER and HFD-LFD, relative to HFD, reduced body weight; reversed obesity-induced alterations in serum insulin, leptin and inflammatory factors; and decreased tumor incidence and mass, often to levels emulating those associated with continuous LFD. Concurrent paclitaxel, versus placebo, enhanced tumor suppression in each group, with greatest benefit in HFD-IER. The diets produced distinct tumoral gene expression and metabolic profiles, with HFD-IER associated with a more favorable (antitumor) metabolic and inflammatory environment. CONCLUSION: In Lkb1fl/flp53fl/fl mice, IER is generally more effective than LFD in promoting weight loss, inhibiting obesity-related endometrial tumor growth (particularly in combination with paclitaxel), and reversing detrimental obesity-related metabolic effects. These findings lay the foundation for further investigations of IER as an EC prevention and treatment strategies in overweight/obesity women.

Antitumor activity and safety of the PD-1 inhibitor retifanlimab in patients with recurrent microsatellite instability-high or deficient mismatch repair endometrial cancer: Final safety and efficacy results from cohort H of the POD1UM-101 phase I study.

OBJECTIVE: Retifanlimab is a humanized immunoglobulin G4 monoclonal antibody against programmed death 1 being investigated in several solid tumor types. We report final results from patients with recurrent microsatellite instability-high (MSI-H)/mismatch repair deficient (dMMR) endometrial cancer treated with retifanlimab in a POD1UM-101 expansion cohort. METHODS: Eligible patients (≥18 years; histologically proven/unresectable/recurrent, MSI-H/dMMR endometrial cancer; checkpoint inhibitor naive) received retifanlimab 500 mg intravenously every 4 weeks for ≤2 years. Primary endpoint was safety/tolerability. RESULTS: At data cutoff (May 17, 2023), 76 patients had received at least one retifanlimab dose. Median (range) age was 67 (49-88) years; 88.2% of patients had recurrent metastatic disease and 80.3% had visceral metastases. Seventy-five patients (98.7%) had received at least one prior systemic therapy. Median retifanlimab exposure was 10.0 (0.03-25.9) months; 23 patients completed treatment. 38 patients (50.0%) had grade ≥3 treatment-emergent adverse events (TEAEs), most commonly anemia (n = 10 [13.2%]). 63 patients (82.9%) had treatment-related AEs (TRAEs; grade ≥3, n = 14 [18.4%]); most common was fatigue (n = 14 [18.4%]). Two patients had TEAEs that led to death; no TRAEs were fatal. 39 patients had objective responses (51.3%; 95% CI, 39.6-63.0%); 19 patients (25.0%) had complete response and 20 (26.3%) had partial response. Median progression-free survival was 12.2 months; 30 patients (76.9%) had duration of response (DOR) ≥12 months. Median DOR was not reached after median follow-up time of 26.0 months. CONCLUSIONS: Retifanlimab was generally well tolerated and demonstrated encouraging anti-tumor activity in patients with pre-treated recurrent MSI-H/dMMR endometrial cancer.

RETRACTED: Cost-effectiveness of chemotherapy and dostarlimab for advanced or recurrent endometrial cancer.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This article has been retracted at the request of the Authors. The authors have independently identified an error in the formula that was utilized to calculate the Quality Adjusted Life Years which invalidates the data and the conclusion of the paper. The authors have contacted the journal requesting to retract the article. Apologies are offered to the readers of the journal for any confusion or inconvenience that may have resulted from the publication of this article.

Mismatch repair deficiency and abnormal p53 expression has significant predictive value for progesterone resistance and endometrial tumorigenesis in patients with endometrial atypical hyperplasia receiving fertility-preserving treatment.

OBJECTIVE: This study aimed to evaluate the prognostic ability of mismatch repair deficiency (MMR-d) and abnormal p53 expression (p53abn) in patients with endometrial atypical hyperplasia (EAH) who underwent fertility-preserving treatment. METHODS: This retrospective study evaluated 51 patients with EAH who underwent fertility-sparing treatment. Endometrial biopsy specimens obtained before hormone therapy were collected and used for immunohistochemical staining for MMR and p53 proteins. Response, relapse, and progression rates were assessed based on age, body mass index, diabetes, polycystic ovary syndrome, reproductive history, MMR status, and p53 status. RESULTS: Overall, 11/51 (21.6%) patients had loss of MMR proteins and 6/51 (11.8%) had p53abn. Patients with MMR-d had lower complete response (CR) rates than those with normal staining patients at 12 months after initial treatment (p = 0.049). Patients with MMR-d had significantly higher relapse rates than those with MMR-p at the 1-year follow-ups after achieving CR (p = 0.035). Moreover, patients with MMR-d had a higher incidence of disease progression at 2, 3, and 4 years after fertility-sparing treatment (p = 0.001, p = 0.01 and p = 0.035, respectively). Patients with p53abn had higher relapse rates than those with p53wt at the 1- and 2-year follow-ups after achieving CR (p = 0.047 and p = 0.036, respectively). Moreover, patients with p53abn had a higher incidence of disease progression at 3 and 4 years after fertility-sparing treatment (p = 0.02 and p = 0.049, respectively). CONCLUSIONS: EAH patients with MMR-d and p53abn have a significantly higher risk of disease relapse and progression. Thus, MMR-d and p53abn may be used as predictive biomarkers of progestin resistance and endometrial tumorigenesis in EAH.

Treatment outcomes according to various progestin treatment strategies in patients with atypical hyperplasia/endometrial intraepithelial neoplasia - Multicenter retrospective study (KGOG2033).

OBJECTIVE: To investigate pathologic complete response (pCR) and recurrence outcomes using various progestin treatment strategies in patients with atypical hyperplasia/endometrial intraepithelial neoplasia (AH/EIN). METHODS: Medical records of patients diagnosed with AH/EIN and undergoing follow-up endometrial biopsy after progestin treatment between 2011 and 2020 were retrospectively reviewed. Clinical factors and treatment outcomes were analyzed according to initial progestin treatment (oral progestin [OP], levonorgestrel-releasing intrauterine device [LNG-IUD], and combination), OP dose, and maintenance treatment using Pearson's χ2, Fisher's exact test, and Kaplan-Meier analysis. RESULTS: Of 124 patients included, 74, 37, and 13 were in the OP, LNG-IUD, and combination groups, respectively. The pCR rate was 79.8% and recurrence rate was 21.2%. The pCR rates within 3 and 6 months were significantly higher in the OP group than in the LNG-IUD group, but were not significantly different within 12 and 24 months. Recurrence rate was significantly higher in the OP group than in the LNG-IUD group. The pCR rate and recurrence rate had no significant differences between the combination group and the other groups. Excluding the LNG-IUD group, 53 and 34 patients received low- and high-dose OP, respectively. The pCR and recurrence rates were comparable between the low- and high-dose OP groups. Maintenance therapy was significantly associated with lower recurrence rate. CONCLUSIONS: Although OP alone achieved more short-term pCR than the other groups, more recurrences occurred after pCR than LNG-IUD alone. High-dose OP as well as combination of OP and LNG-IUD did not increase pCR or reduce recurrence. Maintenance therapy may reduce the recurrence rate after pCR.

Associations of metformin therapy treatment with endometrial cancer risk and prognosis: A systematic review and meta-analysis.

BACKGROUND: Several abstract studies have demonstrated that metformin may be beneficial for preventing and treating endometrial cancer (EC), while the results have been inconsistent and inconclusive. This systematic review and meta-analysis aimed to investigate the association between metformin use and the incidence and mortality of endometrial cancer in diabetic patients. METHODS: A systematic literature search was performed in Pubmed, EMBASE, Web of Science, Cochrane Library, SinoMed, CNKI, Wanfang Data, and VIP from inception to November 2022. The outcome measures were hazard ratios (HRs) comparing the EC incidence and mortality in patients with type 2 diabetes mellitus (T2DM) on metformin and non-metformin. A random or fixed-effects model was applied for data analysis, and subgroup analysis was performed to look for factors of heterogeneity. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessed the evidence's certainty. RESULTS: Eleven studies reported data on EC incidence. The pooled results suggested that the use of metformin was associated with a significantly higher incidence of EC (HR = 1.17, 95% CI 1.09-1.26, P < 0.0001). Further, seventeen studies were included for survival analysis. The pooled data showed that metformin could significantly decrease all-cause mortality (HR = 0.62, 95% CI 0.52-0.74, P < 0.00001) and endometrial cancer-specific mortality (HR = 0.95, 95% CI 0.90, 1.00, P = 0.03). Finally, we noted that metformin was associated with significantly improving the progression-free survival (PFS) of EC patients with T2DM (HR = 0.55, 95% CI 0.44, 0.68, P < 0.00001). CONCLUSIONS: This meta-analysis did not prove that metformin was beneficial for preventing EC. However, metformin could reduce their mortality risk and prolong the progression-free survival time of EC patients with T2DM.