Baseline Serum HE4 But Not Tissue HE4 Expression Predicts Response to the Levonorgestrel-Releasing Intrauterine System in Atypical Hyperplasia and Early Stage Endometrial Cancer.

The levonorgestrel-releasing intrauterine system (LNG-IUS) is a conservative management option for atypical hyperplasia (AH) and low grade early stage endometrial cancer (EEC), but around 1 in 3 patients fail to respond to treatment. The aim of this study was to investigate if serum and/or tissue HE4 expression could predict response to LNG-IUS therapy. Patients with AH or presumed Stage I EEC had serum and endometrial samples taken at baseline and at 3-month intervals over 12 months post-insertion of LNG-IUS. 74 patients were recruited and baseline demographics recorded. Of 57 patients for whom response was histologically determinable, 39 (68%) were responders and 18 (32%) non-responders. Mean baseline serum HE4 was significantly lower in responders (62.1 ± 1.1 pM, 95% confidence interval (CI) 52.7-73.2), compared to non-responders (125.6 ± 1.3 pM, 95% CI 74.5-211.7, p = 0.014), including when considering age, BMI, menopausal status, smoking status, and histological grade as covariables (p = 0.005). Baseline tissue HE4 expression was not significantly different in responders compared to non-responders (p = 0.999). Responders showed a significant mean reduction (-9.8 ± 3.4%, 95% CI -16.7 to -2.8%, p = 0.008) in serum HE4 between baseline and 3 months (p = 0.008), whereas non-responders showed no significant change (p = 0.676). Neither responders nor non-responders showed a significant percentage change in serum HE4 from baseline beyond 3 months (p > 0.05). Change in serum HE4 between baseline and 3 and 6 months and tissue HE4 tissue expression between baseline and 3, 6, and 12 months was not significantly different in responders compared to non-responders (p > 0.05). This study suggests that baseline serum HE4, but not baseline tissue HE4 expression, is independently predictive of response to the LNG-IUS and could be used to guide management decisions.

Optimization of Window Study Endpoints in Endometrial Cancer.

Pre-surgical window studies rely on the accurate quantification of biomarkers as surrogates of disease response. In endometrial cancer, this has traditionally involved comparing immunohistochemical expression in diagnostic endometrial biopsies with the post-treatment hysterectomy specimen. This strategy is at risk of generating erroneous results if significant hypoxia occurs during surgery or delays in fixation of tissues lead to protein loss. Immunohistochemical expression of commonly studied biomarkers in window studies were compared in pre-operative endometrial biopsies and hysterectomy specimens taken on the same day from 75 women with endometrial cancer enrolled in a clinical trial. Differences in expression were correlated with clinico-pathological variables and tissue handling. Expression of Ki-67, markers of the PI3K-Akt-mTOR, and insulin signaling pathways and hormone receptors was significantly lower in the hysterectomy specimen than the corresponding endometrial biopsy (all p < 0.0001). In contrast, expression of the cancer stem cell markers, CD133 and ALDH, were similar in the two specimens. The extent to which protein expression was lost in the hysterectomy specimen was closely correlated with baseline expression in the endometrial biopsy (all p ≤ 0.001). Bisection of the uterus prior to placement in formalin partially preserved protein expression suggesting prompt fixation is critical. These results call into question findings from earlier endometrial cancer window studies which have relied on the hysterectomy specimen for analysis and suggest a post-intervention endometrial biopsy should be included in trials going forward.

PRE-surgical Metformin In Uterine Malignancy (PREMIUM): a Multi-Center, Randomized Double-Blind, Placebo-Controlled Phase III Trial.

PURPOSE: Endometrioid endometrial cancer is strongly associated with obesity and insulin resistance. Metformin, an insulin sensitizer, reduces endometrial tumor growth in vitro. Presurgical window studies allow rapid in vivo assessment of antitumor activity. Previous window studies found metformin reduced endometrial cancer proliferation but these lacked methodological rigor. PREMIUM measured the anti-proliferative effect of metformin in vivo using a robust window study design.Patients and Methods: A multicenter, double-blind, placebo-controlled trial randomized women with atypical hyperplasia or endometrioid endometrial cancer to receive metformin (850 mg daily for 3 days, and twice daily thereafter) or placebo for 1 to 5 weeks until surgery. The primary outcome was posttreatment IHC expression of Ki-67. Secondary outcomes investigated the effect of metformin on markers of the PI3K-Akt-mTOR and insulin signaling pathways and obesity. RESULTS: Eighty-eight women received metformin (n = 45) or placebo (n = 43) and completed treatment. There was no overall difference in posttreatment Ki-67 between the metformin and placebo arms, in an ANCOVA analysis adjusting for baseline Ki-67 expression (mean difference -0.57%; 95% CI, -7.57%-6.42%; P = 0.87). Metformin did not affect expression of markers of the PI3K-Akt-mTOR or insulin signaling pathways, and did not result in weight loss. CONCLUSIONS: Short-term treatment with standard diabetic doses of metformin does not reduce tumor proliferation in women with endometrioid endometrial cancer awaiting hysterectomy. This study does not support a biological effect of metformin in endometrial cancer and casts doubt on its potential application in the primary and adjuvant treatment settings.