Body mass index does not influence post-treatment survival in early stage endometrial cancer: results from the MRC ASTEC trial

Endometrial Cancer in Reproductive-Aged Females: Etiology and Pathogenesis

Endometrial cancer is the most common gynecologic malignancy in developed countries, and the incidence is rising in premenopausal females. Type I EC is more common than Type II EC (80% vs. 20%) and is associated with a hyperestrogenic state. Estrogen unopposed by progesterone is considered to be the main driving factor in the pathogenesis of EC. Studies show that BMI > 30 kg/m2, prolonged duration of menses, nulliparity, presence of polycystic ovarian syndrome, and Lynch syndrome are the most common causes of EC in premenopausal women. Currently, there are no guidelines established to indicate premenopausal patients who should be screened. This review aims to synthesize current data on the etiology, risk factors, presentation, evaluation, and prognosis of endometrial cancer in this population.

The Role of Obesity in the Etiology and Carcinogenesis of Endometrial Cancer

Endometrial cancer, the most common gynecological malignancy, presents a complex public health challenge. While its incidence rises alongside the obesity epidemic, a well-established risk factor for endometrial cancer development, the impact of obesity on survival after diagnosis remains unclear. This review aims to explore the complex relationship between obesity and endometrial cancer's development and survival rates, examining evidence from both epidemiological and clinical studies. It also aims to explore the proposed biological mechanisms by which excess adipose tissue promotes carcinogenesis and contributes to endometrial cancer progression and its negative effects on treatment outcomes. Furthermore, we analyzed the impact of body mass index, inflammation, hormonal imbalances, and their potential effects on endometrial cancer survival rates.

Interventions for weight reduction in obesity to improve survival in women with endometrial cancer

BACKGROUND

This is an updated version of the original Cochrane Review published in Issue 2, 2018. Diagnoses of endometrial cancer are increasing secondary to the rising prevalence of obesity. Obesity plays an important role in promoting the development of endometrial cancer, by inducing a state of unopposed oestrogen excess, insulin resistance and inflammation. It also affects treatment, increasing the risk of surgical complications and the complexity of radiotherapy planning, and may additionally impact on subsequent survival. Weight-loss interventions have been associated with improvements in breast and colorectal cancer-specific survival, as well as a reduction in the risk of cardiovascular disease, which is a frequent cause of death in endometrial cancer survivors.

OBJECTIVES

To evaluate the benefits and harm of weight-loss interventions, in addition to standard management, on overall survival and the frequency of adverse events in women with endometrial cancer who are overweight or obese compared with any other intervention, usual care, or placebo.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was from January 2018 to June 2022 (original review searched from inception to January 2018).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of interventions to facilitate weight loss in women with endometrial cancer who are overweight or obese undergoing treatment for, or previously treated for, endometrial cancer compared with any other intervention, usual care, or placebo.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. overall survival and 2. frequency of adverse events. Our secondary outcomes were 3. recurrence-free survival, 4. cancer-specific survival, 5. weight loss, 6. cardiovascular and metabolic event frequency and 7. quality of Life. We used GRADE to assess certainty of evidence. We contacted study authors to obtain missing data, including details of any adverse events.

MAIN RESULTS

We identified nine new RCTs and combined these with the three RCTs identified in the original review. Seven studies are ongoing.  The 12 RCTs randomised 610 women with endometrial cancer who were overweight or obese. All studies compared combined behavioural and lifestyle interventions designed to facilitate weight loss through dietary modification and increased physical activity with usual care. Included RCTs were of low or very low quality, due to high risk of bias by failing to blind participants, personnel and outcome assessors, and significant loss to follow-up (withdrawal rate up to 28% and missing data up to 65%, largely due to the effects of the COVID-19 pandemic). Importantly, the short duration of follow-up limits the directness of the evidence in evaluating the impact of these interventions on any of the survival and other longer-term outcomes.  Combined behaviour and lifestyle interventions were not associated with improved overall survival compared with usual care at 24 months (risk ratio (RR) mortality, 0.23, 95% confidence interval (CI) 0.01 to 4.55, P = 0.34; 1 RCT, 37 participants; very low-certainty evidence). There was no evidence that such interventions were associated with improvements in cancer-specific survival or cardiovascular event frequency as the studies reported no cancer-related deaths, myocardial infarctions or strokes, and there was only one episode of congestive heart failure at six months (RR 3.47, 95% CI 0.15 to 82.21; P = 0.44, 5 RCTs, 211 participants; low-certainty evidence). Only one RCT reported recurrence-free survival; however, there were no events. Combined behaviour and lifestyle interventions were not associated with significant weight loss at either six or 12 months compared with usual care (at six months: mean difference (MD) -1.39 kg, 95% CI -4.04 to 1.26; P = 0.30, I2 = 32%; 5 RCTs, 209 participants; low-certainty evidence). Combined behaviour and lifestyle interventions were not associated with increased quality of life, when measured using 12-item Short Form (SF-12) Physical Health questionnaire, SF-12 Mental Health questionnaire, Cancer-Related Body Image Scale, Patient Health Questionnaire 9-Item Version or Functional Assessment of Cancer Therapy - General (FACT-G) at 12 months when compared with usual care (FACT-G: MD 2.77, 95% CI -0.65 to 6.20; P = 0.11, I2 = 0%; 2 RCTs, 89 participants; very low-certainty evidence). The trials reported no serious adverse events related to weight loss interventions, for example hospitalisation or deaths. It is uncertain whether lifestyle and behavioural interventions were associated with a higher or lower risk of musculoskeletal symptoms (RR 19.03, 95% CI 1.17 to 310.52; P = 0.04; 8 RCTs, 315 participants; very low-certainty evidence; note: 7 studies reported musculoskeletal symptoms but recorded 0 events in both groups. Thus, the RR and CIs were calculated from 1 study rather than 8).  AUTHORS' CONCLUSIONS: The inclusion of new relevant studies has not changed the conclusions of this review. There is currently insufficient high-quality evidence to determine the effect of combined lifestyle and behavioural interventions on survival, quality of life or significant weight loss in women with a history of endometrial cancer who are overweight or obese compared to those receiving usual care. The limited evidence suggests that there is little or no serious or life-threatening adverse effects due to these interventions, and it is uncertain if musculoskeletal problems were increased, as only one out of eight studies reporting this outcome had any events. Our conclusion is based on low- and very low-certainty evidence from a small number of trials and few women. Therefore, we have very little confidence in the evidence: the true effect of weight-loss interventions in women with endometrial cancer and obesity is currently unknown. Further methodologically rigorous, adequately powered RCTs are required with follow-up of five to 10 years of duration. These should focus on the effects of varying dietary modification regimens, and pharmacological treatments associated with weight loss and bariatric surgery on survival, quality of life, weight loss and adverse events.

The effect of obesity on adipose-derived stromal cells and adipose tissue and their impact on cancer

The significant increase in the incidence of obesity represents the next global health crisis. As a result, scientific research has focused on gaining deeper insights into obesity and adipose tissue biology. As a result of the excessive accumulation of adipose tissue, obesity results from hyperplasia and hypertrophy within the adipose tissue. The functional alterations in the adipose tissue are a confounding contributing factor to many diseases, including cancer. The increased incidence and aggressiveness of several cancers, including colorectal, postmenopausal breast, endometrial, prostate, esophageal, hematological, malignant melanoma, and renal carcinomas, result from obesity as a contributing factor. The increased morbidity and mortality of obesity-associated cancers are attributable to increased hormones, adipokines, and cytokines produced by the adipose tissue. The increased adipose tissue levels observed in obese patients result in more adipose stromal/stem cells (ASCs) distributed throughout the body. ASCs have been shown to impact cancer progression in vitro and in preclinical animal models. ASCs influence tumor biology via multiple mechanisms, including the increased recruitment of ASCs to the tumor site and increased production of cytokines and growth factors by ASCs and other cells within the tumor stroma. Emerging evidence indicates that obesity induces alterations in the biological properties of ASCs, subsequently leading to enhanced tumorigenesis and metastasis of cancer cells. As the focus of this review is the interaction and impact of ASCs on cancer, the presentation is limited to preclinical data generated on cancers in which there is a demonstrated role for ASCs, such as postmenopausal breast, colorectal, prostate, ovarian, multiple myeloma, osteosarcoma, cervical, bladder, and gastrointestinal cancers. Our group has investigated the interactions between obesity and breast cancer and the mechanisms that regulate ASCs and adipocytes in these different contexts through interactions between cancer cells, immune cells, and other cell types present in the tumor microenvironment (TME) are discussed. The reciprocal and circular feedback loop between obesity and ASCs and the mechanisms by which ASCs from obese patients alter the biology of cancer cells and enhance tumorigenesis will be discussed. At present, the evidence for ASCs directly influencing human tumor growth is somewhat limited, though recent clinical studies suggest there may be some link.

Feasibility of Sentinel Lymph Node Sampling in Early-Stage Carcinoma Endometrium: Single-Institution Experience

Introduction

Accurate surgical staging is an essential component in the management of carcinoma endometrium to assess the stage of disease and to tailor adjuvant treatment. Sentinel node technique was introduced as an alternative for extensive lymphadenectomy in early stages to avoid complications associated with lymphadenectomy.

Aims and Objectives

To assess the detection rate and diagnostic accuracy of SLN mapping in patients with early-stage carcinoma endometrium.

Materials and Methods

Prospective validation study involving 30 patients diagnosed to have early-stage carcinoma endometrium. Sentinel nodes were detected by combined methods of radio colloid dye and isosulphan blue dye injection.

Results

Sentinel lymph node was detected in 19 patients (63.4%). 11 patients had no sentinel nodes. Total number of sentinel nodes isolated was 68 with a mean of 2.26 per patient (range 0-4). Ten (33.33%) patients had single sentinel node location, while 9 (30%) had more than 1 sentinel lymph nodes. Twelve patients had bilateral sentinel nodes, and the most frequent location of sentinel node was obturator, 19 (63.3%) especially on right hemi-pelvis. One patient had a hot para-aortic node, while none had blue para-aortic sentinel node. Average number of lymph nodes obtained by lymphadenectomy was 13 per patient (range 7-22). All patients with sentinel node had negative frozen report as well as in histopathology. Two patients in whom no sentinel nodes were detected by either techniques had metastatic nodes in histopathology report.

Conclusion

Detection rate was maximum with radiocolloid dye, and it is better to utilize the technique for less graded tumours and endometrioid variants.

Correlation of Leptin, Proinflammatory Cytokines and Oxidative Stress with Tumor Size and Disease Stage of Endometrioid (Type I) Endometrial Cancer and Review of the Underlying Mechanisms

Endometrioid endometrial cancer is associated with increased BMI and obesity through multiple pathogenetic mechanisms involving hyperestrogenism, hyperinsulinemia, altered adipokine secretion, inflammation, and oxidative stress. In the present study, we aimed to investigate the correlation between BMI, leptin, the proinflammatory cytokines IL-6 and TNFα, reactive oxygen species (ROS), and the traditional prognostic factors T, G, N and M status among type I endometrioid and type II endometrial cancer patients. We enrolled 305 consecutive endometrial cancer patients prospectively. We found that BMI, leptin, and IL-6 significantly correlated with T status, N status, and M status among endometrioid type I endometrial cancer patients. Among type II endometrial cancer patients, BMI and leptin did not correlate with any of the prognostic parameters, whereas there was a positive correlation between IL-6 and the presence of distant metastases. In the multivariate regression analysis, BMI, leptin, and IL-6 were independent predictive variables of T, N, and M status in endometrioid type I endometrial cancer patients. Our study demonstrates that weight gain, adiposity-related adipokines, inflammation, and oxidative stress correlate with the prognostic factors of endometrioid endometrial cancer. Knowledge of the role of obesity-related biological pathways and mediators in the pathogenesis and prognosis of endometrioid endometrial malignancies may offer new perspectives on combined therapeutic strategies that have not been explored to date, both in the advanced disease and in the adjuvant setting.

Prognostic role of computed tomography-based, artificial intelligence-driven waist skeletal muscle volume in uterine endometrial carcinoma

OBJECTIVES

To investigate the impact of computed tomography (CT)-based, artificial intelligence-driven waist skeletal muscle volume on survival outcomes in patients with endometrial cancer.

METHODS

We retrospectively identified endometrial cancer patients who received primary surgical treatment between 2014 and 2018 and whose pre-treatment CT scans were available (n = 385). Using an artificial intelligence-based tool, the skeletal muscle area (cm2) at the third lumbar vertebra (L3) and the skeletal muscle volume (cm3) at the waist level were measured. These values were converted to the L3 skeletal muscle index (SMI) and volumetric SMI by normalisation with body height. The relationships between L3, volumetric SMIs, and survival outcomes were evaluated.

RESULTS

Setting 39.0 cm2/m2 of L3 SMI as cut-off value for sarcopenia, sarcopenia (< 39.0 cm2/m2, n = 177) and non-sarcopenia (≥ 39.0 cm2/m2, n = 208) groups showed similar progression-free survival (PFS; p = 0.335) and overall survival (OS; p = 0.241). Using the median value, the low-volumetric SMI group (< 206.0 cm3/m3, n = 192) showed significantly worse PFS (3-year survival rate, 77.3% vs. 88.8%; p = 0.004) and OS (3-year survival rate, 92.8% vs. 99.4%; p = 0.003) than the high-volumetric SMI group (≥ 206.0 cm3/m3, n = 193). In multivariate analyses adjusted for baseline body mass index and other factors, low-volumetric SMI was identified as an independent poor prognostic factor for PFS (adjusted HR, 1.762; 95% CI, 1.051-2.953; p = 0.032) and OS (adjusted HR, 5.964; 95% CI, 1.296-27.448; p = 0.022).

CONCLUSIONS

Waist skeletal muscle volume might be a novel prognostic biomarker in patients with endometrial cancer. Assessing body composition before treatment can provide important prognostic information for such patients.

Obesity and mortality among endometrial cancer survivors: A systematic review and meta-analysis

Excess body fat is a major risk factor for endometrial cancer incidence, but its impact on recurrence and survival remains unclear. The aim of this systematic review and meta-analysis was to assess the association between excess body fat with recurrence, cancer-specific, and all-cause mortality among endometrial cancer survivors. We searched MEDLINE and EMBASE databases up to July 2021. Risk of bias was assessed with the Ottawa Newcastle Scale. Random effects models estimated pooled hazard ratios for the main associations between body mass index (BMI) and survival outcomes and stratified by endometrial cancer type. Potential heterogeneity and publication bias were evaluated with sensitivity analyses, funnel plots, and Egger's test. Forty-six studies were included, of which 45 estimated body fat with BMI and six used direct waist circumference measures or CT/MRI scans. Higher BMI (≥30 kg/m² ) was associated with increased all-cause mortality (HR = 1.34, 95%CI = 1.12-1.59) and recurrence (HR = 1.28, 95%CI = 1.06-1.56). In sub-group analysis, associations between higher BMI and all-cause mortality were observed for both Types I and II survivors, while recurrence associations were only significant among Type I cases. Obesity at endometrial cancer diagnosis was associated with increased cancer recurrence and all-cause mortality among endometrial cancer survivors but not endometrial cancer-specific mortality.

Impact of socio-economic deprivation on endometrial cancer survival in the North West of England: a prospective database analysis

OBJECTIVE

To assess the impact of socio-economic deprivation on endometrial cancer survival.

DESIGN

Single-centre prospective database study.

SETTING

North West England.

POPULATION

Women with endometrial cancer treated between 2010 and 2015.

METHODS

Areal-level socio-economic status, using the English indices of multiple deprivation from residential postcodes, was analysed in relation to survival using Kaplan-Meier estimation and multivariable Cox regression.

MAIN OUTCOME MEASURES

Overall survival, cancer-specific survival and patterns and rates of recurrence.

RESULTS

A total of 539 women, with a median age of 66 years (interquartile range, IQR 56-73 years) and a body mass index (BMI) of 32 kg/m2 (IQR 26-39 kg/m2 ), were included in the analysis. Women in the most deprived social group were younger (median 64 years, IQR 55-72 years) and more obese (median 34 kg/m2 , IQR 28-42 kg/m2 ) than women in the least deprived group (median age 68 years, IQR 60-74 years; BMI 29 kg/m2 , IQR 25-36 kg/m2 ; P = 0.002 and <0.001, respectively). There were no differences in endometrial cancer type, stage or grade between social groups. There was no difference in recurrence rates, however, women in the middle and most deprived social groups were more likely to present with distant/metastatic recurrence (80.6 and 79.2%, respectively) than women in the least deprived group (43.5%, P < 0.001). Women in the middle and most deprived groups had a two-fold (adjusted hazard ratio, HR = 2.00, 95% CI 1.07-3.73, P = 0.030) and 53% (adjusted HR = 1.53, 95% CI 0.77-3.04, P = 0.221) increase in cancer-specific mortality compared with women in the least deprived group. There were no differences in overall survival.

CONCLUSIONS

We found that socio-economically deprived women with endometrial cancer were more likely to develop fatal recurrence. Larger studies are needed to confirm these findings and to identify modifiable contributing factors.

TWEETABLE ABSTRACT

Socio-economic deprivation is linked to an increased risk of death from endometrial cancer in the North West of England.

Gender Differences in Obesity-Related Cancers

PURPOSE OF REVIEW

In this review, we summarize the role of obesity in carcinogenesis, providing details on specific cancer sites. Special emphasis is given to gender differences in obesity-related cancers and on the effect of bariatric surgery on cancer risk.

RECENT FINDINGS

Accumulating evidence has highlighted the detrimental role of overweight/obesity in cancer, with almost 55% of cancers diagnosed in women and 24% diagnosed in men considered overweight- and obesity-related cancers. Sufficient data have shown that higher BMI is associated with risk of gynecologic malignancies (mainly breast and endometrial cancers) as well as cancers in sites such as the esophagus (adenocarcinoma), gastric cardia, colon, rectum, liver, gallbladder, pancreas, kidney, thyroid gland, and multiple myeloma. The main mechanisms underlying this relationship include the insulin/IGF1 system, the effect of sex hormones, and adipocytokines. Marked differences may be seen in specific cancer sites when comparing men to women. There is a higher overall incidence of obesity-related cancers among females (endometrial, ovarian, and postmenopausal female breast cancers), whereas cancers that concern both sexes show a higher incidence in males, particularly esophageal adenocarcinoma (male to female ratio: 9: 1 in the USA). Additionally, bariatric surgery has provided evidence of lowering overall cancer risk in patients with morbid obesity. Interestingly, bariatric surgery may lower overall cancer risk in women within the first 5 years after surgery due to the reduced risk of breast and endometrial cancer, and non-Hodgkin lymphoma. Obesity constitutes the base for marked metabolic, hormonal, and inflammatory alterations, including increased cancer risk in both men and women. Implementation of early obesity prevention strategies could ameliorate the continuously increasing incidence of cancer attributed to obesity.

A BMI-category distribution pattern of intrinsic and treatment-related prognostic factors in endometrial cancer

OBJECTIVE

In patients with endometrial cancer, obesity is associated with favorable prognostic characteristics but not with prolonged survival. The aim of this study was to elucidate the reason for this clinical paradox.

METHODS

We retrospectively reviewed 1173 patients with endometrial cancer. Patients were divided into a non-obese group [body mass index (BMI) < 30 kg/m2], class I obesity group (BMI 30-35 kg/m2) and class II obesity group (BMI ≥ 35 kg/m2). The relationship between clinicopathological factors and disease-specific survival (DSS) was analyzed by Cox regression analysis. To correct for three-time significance testing, we used the Bonferroni method, giving the level of probability at which findings were considered significant as P < 0.0167.

RESULTS

Three disease-intrinsic variables-older age, advanced stage and high-risk histology-and three treatment-related variables-no hysterectomy, no lymphadenectomy and no chemotherapy-were independently associated with poor DSS. DSS was similar among the three groups of patients even though the proportion of patients with plural pretreatment-related unfavorable risk factors significantly decreased with increment of BMI category (40.1 vs. 27.5 vs. 17.6%, P = 0.0003). The proportion of patients with plural treatment-related unfavorable prognostic factors significantly increased with increment of BMI category (21.3 vs. 26.7 vs. 39.3%, P = 0.0072).

CONCLUSIONS

Poor-quality surgical staging in obese women may result in worse than expected survival outcomes.

The Obesity Paradox in Cancer: Epidemiologic Insights and Perspectives

PURPOSE OF REVIEW

Controversy exists whether excess body fatness (measured by body mass index (BMI)) is associated with better cancer survival ("obesity paradox"). Here, we review the obesity paradox in cancer research and discuss potential explanations and future research directions.

RECENT FINDINGS

Overweight and obese cancer patients have better survival for diverse cancers. This apparent obesity paradox may be largely explained by methodological limitations including reverse causation, selection bias, confounding, and reliance of BMI as a measure of adiposity in cancer patients. A growing number of studies show promising evidence that precisely quantified body composition can provide important prognostic information in cancer care, such that low muscle and high adiposity are associated with worse clinical outcomes in cancer patients. The term obesity paradox in cancer, implying a causally beneficial role of adiposity, is misleading. Understanding the role of muscle and adiposity may reduce the confusion and inform precision oncology care.

Obesity and Cancer Treatment Outcomes: Interpreting the Complex Evidence

A wealth of epidemiological evidence, combined with plausible biological mechanisms, present a convincing argument for a causal relationship between excess adiposity, commonly approximated as body mass index (BMI, kg/m²), and incident cancer risk. Beyond this relationship, there are a number of challenges posed in the context of interpreting whether being overweight (BMI 25.0-29.9 kg/m²) or obese (BMI ≥ 30.0 kg/m²) adversely influences disease progression, cancer mortality and survival. Elevated BMI (≥ 25.0 kg/m²) may influence treatment selection of, for example, the approach to surgery; the choice of chemotherapy dosing; the inclusion of patients into randomised clinical trials. Furthermore, the technical challenges posed by an elevated BMI may adversely affect surgical outcomes, for example, morbidity (increasing the risk of surgical site infections), reduced lymph node harvest (and subsequent risk of under-staging and under-treatment) and increased risk of margin positivity. Suboptimal chemotherapy dosing, associated with capping chemotherapy in obese patients as an attempt to avoid excess toxicity, might be a driver of poor prognostic outcomes. By contrast, the efficacy of immune checkpoint inhibition may be enhanced in patients who are obese, although in turn, this observation might be due to reverse causality. So, a central research question is whether being overweight or obese adversely affects outcomes either directly through effects of cancer biology or whether adverse outcomes are mediated through indirect pathways. A further dimension to this complex relationship is the obesity paradox, a phenomenon where being overweight or obese is associated with improved survival where the reverse is expected. In this overview, we describe a framework for evaluating methodological problems such as selection bias, confounding and reverse causality, which may contribute to spurious interpretations. Future studies will need to focus on prospective studies with well-considered methodology in order to improve the interpretation of causality.

Patient perceptions and understanding of obesity related endometrial cancer

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40% of patients disagree that being overweight is a risk factor for cancer.

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85% of patients would prefer multimodal weight loss approach to cancer care.

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82.1% of patients would consider medical or surgical approaches to treatment.

Obesity is the greatest risk factor for endometrial cancer. There is often a lack of recognition amongst patients about this risk. Evidence for weight-loss in the management of endometrial cancer is emerging. This was questionnaire-based study, that examined opinions and attitudes of patients with endometrial cancer and obesity towards obesity as a risk factor for cancer as well as examining their willingness to engage in weight loss interventions as an alternative treatment to endometrial cancer. This survey was conducted in a gynaeoncology out-patient department in Ireland. A total of 45/50 (90%) of questionnaires were completed. The majority of the patients questioned (86.7%; 39/45) agreed that obesity is a disease. Just over half of the cohort (53.3%; 24/45) believed that obesity can cause cancer. Over one-third, 39.9% (18/45) either disagreed or strongly disagreed that obesity is a risk factor for endometrial cancer while 35.5% (16/45) agreed or strongly agreed. Two-thirds (66.6%; 30/45) knew that the greatest amount of weight could be lost through metabolic surgery. Over three-quarters (82.1%; 37/45) of patients surveyed would be willing to engage in a combination of treatments in order to achieve weight-loss should it be proven to have a role in the management of endometrial cancer. This study demonstrates a need for patient education regarding the strong relationship between obesity and endometrial cancer risk. Patients are willing to consider weight loss interventions if they were proven to be as safe and effective as pelvic surgery in the management of endometrial cancer.

The Importance of Body Composition in Explaining the Overweight Paradox in Cancer-Counterpoint

Despite a greater risk of cancer associated with higher BMI, overweight (BMI 25-<30 kg/m²) and class I obese (BMI 30-<35 kg/m²) patients often have a paradoxically lower risk of overall mortality after a cancer diagnosis, a phenomenon called the "obesity paradox." Only when patients exceed a BMI ≥35 kg/m² are elevations in mortality risk consistently noted. This paradox has been dismissed as the result of methodologic bias, which we will describe and debate here. However, even if such bias influences associations, there is growing evidence that body composition may in part explain the paradox. This phenomenon may more accurately be described as a BMI paradox. That is, BMI is a poor proxy for adiposity and does not distinguish muscle from adipose tissue, nor describe adipose tissue distribution. Low muscle mass is associated with higher risk of recurrence, overall and cancer-specific mortality, surgical complications, and treatment-related toxicities. Patients with who are overweight or obese have on average higher levels of muscle than their normal-weight counterparts. Also, there is some evidence that patients with moderate levels of subcutaneous adipose tissue may have lower mortality. More research utilizing body composition is needed to clarify the effects of adiposity on cancer mortality. Cancer Res; 78(8); 1906-12. ©2018 AACR.

Diagnostic Accuracy of Clinical Biomarkers for Preoperative Prediction of Lymph Node Metastasis in Endometrial Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

In endometrial carcinoma (EC), preoperative classification is based on histopathological criteria, with only moderate diagnostic performance for the risk of lymph node metastasis (LNM). So far, existing molecular classification systems have not been evaluated for prediction of LNM. Optimized use of clinical biomarkers as recommended by international guidelines might be a first step to improve tailored treatment, awaiting future molecular biomarkers.

AIM

To determine the diagnostic accuracy of preoperative clinical biomarkers for the prediction of LNM in endometrial cancer.

METHODS

A systematic review was performed according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Studies identified in MEDLINE and EMBASE were selected by two independent reviewers. Included biomarkers were based on recommended guidelines (cancer antigen 125 [Ca-125], lymphadenopathy on magnetic resonance imaging, computed tomography, and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography [¹⁸FDG PET-CT]) or obtained by physical examination (body mass index, cervical cytology, blood cell counts). Pooled sensitivity, specificity, area under the curve (AUC), and likelihood ratios were calculated with bivariate random-effects meta-analysis. Likelihood ratios were classified into small (0.5-1.0 or 1-2.0), moderate (0.2-0.5 or 2.0-5.0) or large (0.1-0.2 or ≥ 5.0) impact.

RESULTS

Eighty-three studies, comprising 18,205 patients, were included. Elevated Ca-125 and thrombocytosis were associated with a moderate increase in risk of LNM; lymphadenopathy on imaging with a large increase. Normal Ca-125, cytology, and no lymphadenopathy on ¹⁸FDG PET-CT were associated with a moderate decrease. AUCs were above 0.75 for these biomarkers. Other biomarkers had an AUC <0.75 and incurred only small impact.

CONCLUSION

Ca-125, thrombocytosis, and imaging had a large and moderate impact on risk of LNM and could improve preoperative risk stratification.

IMPLICATIONS FOR PRACTICE

Routine lymphadenectomy in clinical early-stage endometrial carcinoma does not improve outcome and is associated with 15%-20% surgery-related morbidity, underlining the need for improved preoperative risk stratification. New molecular classification systems are emerging but have not yet been evaluated for the prediction of lymph node metastasis. This article provides a robust overview of diagnostic performance of all clinical biomarkers recommended by international guidelines. Based on these, at least measurement of cancer antigen 125 serum level, assessment of thrombocytosis, and imaging focused on lymphadenopathy should complement current preoperative risk stratification in order to better stratify these patients by risk.

Linking obesity-induced leptin-signaling pathways to common endocrine-related cancers in women

Obesity is related to many major diseases and cancers. Women have higher rates of obesity and obesity is linked to commonly occurring cancers in women. However, there is a lack of knowledge of the unique mechanism(s) involved in each type of cancer. The objective of this review is to highlight the need for novel experimental approaches and a better understanding of the common and unique pathways to resolve controversies regarding the role of obesity in cancer. In women, there is a link between hormones and obesity-associated genes in cancer development. Leptin is an obesity-associated gene that has been studied extensively in cancers; however, whether the defect is in the leptin gene or in its signaling pathways remains unclear. Both leptin and its receptor have been positively correlated with cancer progression in some endocrine-related cancers in women. This review offers an up-to-date and cohesive review of both upstream and downstream pathways of leptin signaling in cancer and a comprehensive picture of cancer pathogenesis in light of current evidence of leptin effects in several major types of cancer. This work is intended to aid in the design of better therapeutic strategies for obese/overweight women with cancer.

Body mass index and mortality in patients with gastric cancer: a large cohort study

BACKGROUND

The effects of obesity on prognosis in gastric cancer are controversial.

AIMS

To evaluate the association between body mass index (BMI) and mortality in patients with gastric cancer.

METHODS

A single-institution cohort of 7765 patients with gastric cancer undergoing curative gastrectomy between October 2000 and June 2016 was categorized into six groups based on BMI: underweight (< 18.5 kg/m²), normal (18.5 to < 23 kg/m²), overweight (23 to < 25 kg/m²), mildly obese (25 to < 28 kg/m²), moderately obese (28 to < 30 kg/m²), and severely obese (≥ 30 kg/m²). Hazard ratios (HRs) for overall survival (OS) and disease-specific survival (DSS) were calculated using Cox proportional hazard models.

RESULTS

We identified 1279 (16.5%) all-cause and 763 (9.8%) disease-specific deaths among 7765 patients over 83.05 months (range 1.02-186.97) median follow-up. In multivariable analyses adjusted for statistically significant clinicopathological characteristics, preoperative BMI was associated with OS in a non-linear pattern. Compared with normal-weight patients, underweight patients had worse OS [HR 1.42; 95% confidence interval (CI) 1.15-1.77], whereas overweight (HR 0.84; 95% CI 0.73-0.97), mildly obese (HR 0.77; 95% CI 0.66-0.90), and moderately obese (HR 0.77; 95% CI 0.59-1.01) patients had better OS. DSS exhibited a similar pattern, with lowest mortality in moderately obese patients (HR 0.58; 95% CI 0.39-0.85). Spline analysis showed the lowest all-cause mortality risk at a BMI of 26.67 kg/m².

CONCLUSION

In patients undergoing curative gastric cancer surgery, those who were overweight or mildly-to-moderately obese (BMI 23 to < 30 kg/m²) preoperatively had better OS and DSS than normal-weight patients.

The Obesity Paradox in Cancer: How Important Is Muscle?

Although higher body mass index (BMI) increases the incidence of many cancers, BMI can also exhibit a null or U-shaped relationship with survival among patients with existing disease; this association of higher BMI with improved survival is termed the obesity paradox. This review discusses possible explanations for the obesity paradox, the prevalence and consequences of low muscle mass in cancer patients, and future research directions. It is unlikely that methodological biases, such as reverse causality or confounding, fully explain the obesity paradox. Rather, up to a point, higher BMI may truly be associated with longer survival in cancer patients. This is due, in part, to the limitations of BMI, which scales weight to height without delineating adipose tissue distribution or distinguishing between adipose and muscle tissue. Thus, cancer patients with higher BMIs often have higher levels of protective muscle. We assert that more precise measures of body composition are required to clarify the relationship of body size to cancer outcomes, inform clinical decision-making, and help tailor lifestyle interventions.

The obesity paradox in cancer: clinical insights and perspectives

A series of evidence demonstrated that obesity represents an established risk factor for an increase in the incidence of multiple cancer types and for poor cancer survival. Nevertheless, recent studies suggested that, in a series of cancers, patients with a normal body mass index (BMI) have worse outcomes than obese patients. This phenomenon, named 'obesity paradox' or 'reverse epidemiology' in cancer, is not well understood and presents controversial aspects. Therefore, this review aims to explore the available studies concerning the relationship between obesity and cancer incidence or survival and to highlight the hypothetical explanations and the methodological framework. In this regard, we underline the limits of BMI as a potential marker of adiposity and the relevance to assessing body composition, beyond the body size. Further studies are needed to define the impact of obesity in cancer patients, to tailor weight management after cancer diagnosis and to hopefully improve overall clinical outcome.

Interventions for weight reduction in obesity to improve survival in women with endometrial cancer

BACKGROUND

Diagnoses of endometrial cancer are increasing secondary to the rising prevalence of obesity. Obesity plays an important role in promoting the development of endometrial cancer, by inducing a state of unopposed oestrogen excess, insulin resistance and inflammation. It also affects treatment, increasing the risk of surgical complications and the complexity of radiotherapy planning, and may additionally impact on subsequent survival. Weight-loss interventions have been associated with improvements in breast and colorectal cancer-specific survival as well as a reduction in the risk of cardiovascular disease, a frequent cause of death in endometrial cancer survivors.

OBJECTIVES

To determine the impact of weight-loss interventions, in addition to standard management of endometrial cancer, on overall survival and the frequency of adverse events.Secondary objectives include an assessment of weight-loss interventions on endometrial cancer-specific survival, weight loss achieved, cardiovascular event frequency and quality of life both overall and stratified according to patient body mass index (BMI), where possible.

SEARCH METHODS

This review searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase and reference lists of articles, trial registries, and international gynaecological oncology conference abstracts from inception to January 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of interventions to facilitate weight loss in overweight or obese women undergoing treatment for, or previously treated for, endometrial cancer were selected.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed trial quality, and extracted data with disagreements resolved by a third review author. Study authors were contacted to obtain missing data, including details of any adverse events.

MAIN RESULTS

We included three RCTs in the review, randomising a total of 161 overweight and obese women with endometrial cancer. All studies compared combined behavioural and lifestyle interventions to facilitate weight loss through dietary modification and increased physical activity. The included RCTs were of low or very low quality, due to high risk of bias by failing to blind participants, personnel and outcome assessors, and significant loss to follow-up (attrition rate up to 29%).Combined behaviour and lifestyle interventions were not associated with improved overall survival (risk ratio (RR mortality), 0.23 95% confidence interval (CI) 0.01 to 4.55, P = 0.34, one RCT, 37 participants; very low-certainty evidence) compared with usual care at 24 months. There was no evidence that such interventions were associated with improvements in cancer-specific survival or cardiovascular event frequency as no cancer-related deaths, myocardial infarctions or strokes were reported in the included studies. None of the included RCTs reported data for the outcome of recurrence-free survival. Combined behaviour and lifestyle interventions were not associated with significant weight loss at either six months (mean difference (MD) -1.88 kg, 95% CI -5.98 to 2.21 kg, P = 0.37, three RCTs, 131 participants, I²= 0%; low-certainty evidenc e)or 12 months (MD -8.98 kg, 95% CI -19.88 to 1.92 kg, P = 0.11, two RCTs, 91 participants, I²= 0%; very low-certainty evidence) when compared with usual care. Combined behaviour and lifestyle interventions were not associated with increased quality of life, when measured using either the SF-12 Physical Health questionnaire or FACT-G at six months (FACT-G MD 2.51, 95% CI -5.61 to 10.64, P = 0.54, two RCTs, 95 participants, I²= 83%; very low-certainty evidence), or by FACT-G alone at 12 months (MD 2.77, 95% CI -0.65 to 6.20, P = 0.11, two RCTs, 89 participants, I²= 0%; very low-certainty evidence) when compared with usual care. No serious adverse events, for example hospitalisation or deaths, were reported in included trials. Lifestyle and behavioural interventions were associated with a higher risk of musculoskeletal symptoms (RR 19.03, 95% CI 1.17, 310.52, P = 0.04, two RCTs, 91 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

There is currently insufficient high-quality evidence to determine the effect of combined lifestyle and behavioural interventions on survival, quality of life, or significant weight loss in women with a history of endometrial cancer compared to those receiving usual care. The limited evidence suggests that there is little or no serious or life-threatening adverse effects due to these interventions, although musculoskeletal problems were increased, presumably due to increased activity levels. Our conclusion is based on low- and very low-quality evidence from a small number of trials and very few patients. We therefore have very little confidence in the evidence: the true effect of weight-loss interventions in obese women with endometrial cancer is currently not known.Further methodologically-rigorous, adequately-powered RCTs are required with follow-up of 5 to 10 years duration. These should focus on the effects of varying dietary modification regimens, pharmacological treatments associated with weight loss and bariatric surgery on survival, quality of life, weight loss and adverse events.

Proteomic profiling of endometrioid endometrial cancer reveals differential expression of hormone receptors and MAPK signaling proteins in obese versus non-obese patients

Endometrial cancer development is strongly linked to obesity, but knowledge regarding the influence of excess weight on endometrial tumor signaling pathways remains scarce. We therefore analyzed reverse phase protein array (RPPA) data for obesity-related protein expression patterns, using one training (n=272) and two test cohorts (n=68; n=178) of well-annotated samples from women treated for endometrioid endometrial cancer. Gene expression profiling and immunohistochemistry were used for cross-platform validation. Body mass index (BMI) was significantly correlated with progesterone receptor (PR) expression and a hormone receptor protein signature, across all cohorts. In two of the cohorts, BMI was negatively correlated with RTK- and MAPK-pathway activation, particularly phosphorylated MAPK T202 Y204 (p-MAPK) level. Using stepwise selection modelling, a BMI-associated protein signature, including phosphorylated estrogen receptor α S118 (p-ERα) and p-MAPK, was identified. In the subset of FIGO stage 1, grade 1-2 tumors, obese patients (BMI≥30) had better survival compared to non-obese patients in the two cohorts with longest follow-up time (p=0.042, p=0.058). Non-obese patients had higher p-MAPK levels, whereas obese patients had higher p-ERα levels and enrichment of gene signatures related to estrogen signaling, inflammation, immune signaling and hypoxia. In subgroup analysis of non-obese patients with FIGO stage 1 tumors, low PI3K-activation was associated with reduced survival (p=0.002, training cohort). In conclusion, increasing BMI is associated with increased PR and p-ERα levels and reduced MAPK signaling, both in all patients and in subsets with predicted excellent prognosis. The MAPK-pathway represents a potential therapeutic target in non-obese patients with low stage and low grade tumors.

The unrecognized burden of cardiovascular risk factors in women newly diagnosed with endometrial cancer: A prospective case control study

BACKGROUND

Cardiovascular disease is a major cause of death in endometrial cancer survivors. The aim of this study was to determine whether women newly diagnosed with endometrial cancer have a higher prevalence of cardiovascular risk factors than the general population.

METHODS

The prevalence of adequately treated and unrecognized/inadequately treated cardiovascular risk factors and the corresponding 10-year cardiovascular risk by QRISK2 score was measured in 150 consecutive women undergoing primary treatment for endometrioid endometrial cancer in the North West of England, and 746 age and ethnicity-matched control women from the Health Survey for England 2014.

RESULTS

Women with endometrial cancer had higher proportions of obesity (BMI≥30 60.7% vs. 32.4%, p<0.0001) and a preponderance of unrecognized and inadequately treated cardiovascular risk factors. Compared with controls, endometrial cancer cases had a higher prevalence of incident hyperglycemia (57.2%vs.11.5%, p<0.0001), total: HDL cholesterol ratio>4.5 (26.7%vs.13.7%, p<0.0001), and were more likely to have three or more cardiovascular risk factors (22%vs.6%, p<0.0001). This equates to a higher 10-year cardiovascular risk (median QRISK2 score 12.6% vs. 8.8%, p<0.0001). Optimization of risk factors would have a greater impact on absolute cardiovascular disease risk for cases than controls (QRISK2 score reduction 1.8% vs. 0.7%).

CONCLUSIONS

Women undergoing primary treatment for endometrial cancer have a higher prevalence of cardiovascular risk factors than women without the disease. Early identification and treatment of these risk factors could improve outcomes for endometrial cancer survivors.

Lymphadenectomy for the management of endometrial cancer

BACKGROUND

This is an update of a previous Cochrane review published in Issue 1, 2010 and updated in Issue 9, 2015. The role of lymphadenectomy in surgical management of endometrial cancer remains controversial. Lymph node metastases can be found in approximately 10% of women who before surgery are thought to have cancer confined to the womb. Removal of all pelvic and para-aortic lymph nodes (lymphadenectomy) at initial surgery has been widely advocated, and pelvic and para-aortic lymphadenectomy remains part of the FIGO (International Federation of Gynaecology and Obstetrics) staging system for endometrial cancer. This recommendation is based on data from studies that suggested improvement in survival following pelvic and para-aortic lymphadenectomy. However, these studies were not randomised controlled trials (RCTs), and treatment of pelvic lymph nodes may not confer a direct therapeutic benefit, other than allocating women to poorer prognosis groups. Furthermore, the Cochrane review and meta-analysis of RCTs of routine adjuvant radiotherapy to treat possible lymph node metastases in women with early-stage endometrial cancer found no survival advantage. Surgical removal of pelvic and para-aortic lymph nodes has serious potential short-term and long-term sequelae. Therefore, it is important to investigate the clinical value of this treatment.

OBJECTIVES

To evaluate the effectiveness and safety of lymphadenectomy for the management of endometrial cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase to June 2009 for the original review, updated the search to June 2015 for the last updated version and further extended the search to March 2017 for this version of the review. We also searched registers of clinical trials, abstracts of scientific meetings, and reference lists of included studies, and we contacted experts in the field.

SELECTION CRITERIA

RCTs and quasi-RCTs that compared lymphadenectomy versus no lymphadenectomy in adult women diagnosed with endometrial cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias. Hazard ratios (HRs) for overall and progression-free survival and risk ratios (RRs) comparing adverse events in women who received lymphadenectomy versus those with no lymphadenectomy were pooled in random-effects meta-analyses. We assessed the quality of the evidence using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach.

MAIN RESULTS

978 unique references were identified via the search strategy. All but 50 were excluded by title and abstract screening. Three RCTs met the inclusion criteria; for one small RCT, data were insufficient for inclusion in the meta-analysis. The two RCTs included in the analysis randomly assigned 1945 women, reported HRs for survival adjusted for prognostic factors and based on 1851 women and had an overall low risk of bias, as they satisfied four of the assessment criteria. The third study had an overall unclear risk of bias, as information provided was not adequate concerning random sequence generation, allocation concealment, blinding, or completeness of outcome reporting.Results of the meta-analysis remained unchanged from the previous versions of this review and indicated no differences in overall and recurrence-free survival between women who underwent lymphadenectomy and those who did not undergo lymphadenectomy (pooled hazard ratio (HR) 1.07, 95% confidence interval (CI) 0.81 to 1.43; HR 1.23, 95% CI 0.96 to 1.58 for overall and recurrence-free survival, respectively) (1851 participants, two studies; moderate-quality evidence).We found no difference in risk of direct surgical morbidity between women who underwent lymphadenectomy and those who did not undergo lymphadenectomy. However, women who underwent lymphadenectomy had a significantly higher risk of surgery-related systemic morbidity and lymphoedema/lymphocyst formation than those who did not undergo lymphadenectomy (RR 3.72, 95% CI 1.04 to 13.27; RR 8.39, 95% CI 4.06 to 17.33 for risk of surgery-related systemic morbidity and lymphoedema/lymphocyst formation, respectively) (1922 participants, two studies; high-quality evidence).

AUTHORS' CONCLUSIONS

This review found no evidence that lymphadenectomy decreases risk of death or disease recurrence compared with no lymphadenectomy in women with presumed stage I disease. Evidence on serious adverse events suggests that women who undergo lymphadenectomy are more likely to experience surgery-related systemic morbidity or lymphoedema/lymphocyst formation. Currently, no RCT evidence shows the impact of lymphadenectomy in women with higher-stage disease and in those at high risk of disease recurrence.

Significance of body weight change during fertility-sparing progestin therapy in young women with early endometrial cancer

OBJECTIVE

To evaluate the influence of body weight change during fertility-sparing progestin therapy on oncologic and reproductive outcomes in young women with early-stage endometrial cancer who did not complete child bearing.

METHODS

This multicenter, retrospective study included 154 young patients with well-differentiated, endometrium-confined endometrioid endometrial adenocarcinoma on magnetic resonance imaging who received fertility-sparing progestin therapy.

RESULTS

The mean body weight and body mass index (BMI) at baseline and progestin therapy completion was 65.3±16.2 and 66.5±15.9kg (P=0.044), respectively, and 25.51±5.99 and 25.99±5.94kg/m² (P=0.034), respectively. During progestin therapy, 51 (33.1%), 29 (18.8%), and 74 patients (48.1%) had weight loss, no weight change, and weight gain, respectively, of which 11 (7.1%) had 10% weight loss and 30 (19.5%) had 10% weight gain. A pretreatment BMI of ≥25kg/m² was significantly associated with a lower complete response rate to progestin therapy (P=0.003) and a high recurrence rate (P=0.033). A posttreatment BMI of ≥25kg/m² was also a significant factor for high recurrence rate (P=0.049). However, weight change during therapy was not significantly associated with complete response or recurrence rate. Pre and posttreatment BMIs and weight change were not associated with pregnancy and live birth rates.

CONCLUSION

Weight change during progestin therapy has little influence on complete response, recurrence, pregnancy, and live birth rates. However, pre and posttreatment BMIs of ≥25kg/m² were significant predictors for poor treatment response and high recurrence. Therefore, it is important to maintain patients' normal BMIs during progestin therapy.

BGCS uterine cancer guidelines: Recommendations for practice

The British Gynaecological Cancer Society has issued the first Endometrial (Uterine) Cancer guidelines as recommendation for practice for the UK.

The assessment of local response using magnetic resonance imaging at 3- and 6-month post chemoradiotherapy in patients with anal cancer

OBJECTIVES

To assess the use of MRI-determined tumour regression grading (TRG) in local response assessment and detection of salvageable early local relapse after chemoradiotherapy (CRT) in patients with anal squamous cell carcinoma (ASCC).

METHODS

From a prospective database of patients with ASCC managed through a centralised multidisciplinary team, 74 patients who completed routine post-CRT 3- and 6-month MRIs (2009-2012) were reviewed. Two radiologists blinded to the outcomes consensus read and retrospectively assigned TRG scores [1 (complete response) to 5 (no response)] and related these to early local relapse (within 12 months) and disease-free survival (DFS).

RESULTS

Seven patients had early local relapse. TRG 1/2 scores at 3 and 6 months had a 100 % negative predictive value; TRG 4/5 scores at 6 months had a 100 % positive predictive value. All seven patients underwent salvage R0 resections. We identified a novel 'tram-track' sign on MRI in over half of patients, with an NPV for early local relapse of 83 % at 6 months. No imaging characteristic or TRG score independently prognosticated for late relapse or 3-year DFS.

CONCLUSIONS

Post-CRT 3- and 6-month MRI-determined TRG scores predicted salvageable R0 early local relapses in patients with ASCC, challenging current clinical guidelines.

KEY POINTS

• Post-chemoradiotherapy MRI (3 and 6 months) helps local response assessment in ASCC. • The MRI-TRG system can be used reproducibly in patients with ASCC. • The TRG system facilitates patient selection for examination under anaesthesia and biopsy. • The use of MRI-TRG predicts for detection of salvageable early local relapses. • The TRG system allows for a standardised follow-up pathway.

How to Manage the Obese Patient With Cancer

Purpose

Obesity (body mass index [BMI] ≥ 30 kg/m2) is common among patients with cancer. We reviewed management issues in the obese patient with cancer, focusing on how obesity influences treatment selection (including chemotherapy dosing), affects chemotherapy toxicity and surgical complications, and might be a treatment effect modifier.

Methods

The majority of evidence is drawn from observational studies and secondary analyses of trial data, typically analyzed in N × 3 BMI categories (normal weight, overweight, and obese) matrix structures. We propose a methodological framework for interpretation focusing on sample size and composition, nonlinearity, and unmeasured confounding.

Results

There is a common perception that obesity is associated with increased treatment-related toxicity. Accordingly, cytotoxic chemotherapy dose reduction is common in patients with elevated BMI. Contrary to this, there is some evidence that full dosing in obese patients does not result in increased toxicity. However, these data are from a limited number of regimens, and fail to fully capture cytotoxic drug pharmacodynamics and pharmacokinetic variability in obese patients. Among patients undergoing surgery, there is evidence that elevated BMI is associated with increased perioperative mortality and increased rates of infectious complications. A novel finding is that these relationships hold after surgery for malignancy, but not for benign indications. There are biologic plausibilities that obesity might be an effect modifier of treatment, but supporting evidence from clinical studies is inconsistent.

Conclusion

In line with the ASCO 2012 guidelines, chemotherapy dosing is probably best performed using actual body weight in obese patients. However, specific regimens known to be associated with increased toxicity in this group should be used with caution. There is no guidance on dose for obese patients treated with biologic agents. Currently, there are no specific recommendations for the surgical management of the obese patient with cancer.

Features of omental adipose tissue in endometrial cancer patients with 'standard' or 'metabolically healthy' obesity: associations with tumor process characteristics

Purpose

Adipose tissue products may contribute to endometrial cancer (EC) initiation and further growth that encourages the analysis of this issue in patients with different obesity phenotypes.

Methods/patients

Omental fat depot characteristics were studied in EC patients (n = 57) with “standard” (SO) or “metabolically healthy” (MHO) obesity. Collected omental samples were evaluated by immunohistochemistry /IHC/ for brown fat marker UCP1, CYP19 (aromatase) and macrophage infiltration markers (CD68, CD163, crown-like structures/CLS) expression. Total RNA extracted from the same samples was investigated for UCP1, CYP19, PTEN and adipokine omentin mRNA.

Results

Immunohistochemistry data revealed a statistically significant increase in aromatase and CD68 expression and tendency to increase of UCP1 expression in SO patients’ omental fat compared to samples obtained from MHO patients. Additionally, positive correlation of EC clinical stage with UCP1 protein and its mRNA content in omental fat was pronounced in MHO as well as SO group, while with omentin mRNA it was discovered only in patients with SO. An inclination to the correlation with better tumor differentiation was seen for UCP1 and CD68 protein expression in patients with MHO and with worse (high grade) differentiation—for CD68 expression in the group with SO.

Conclusions

In aggregate, this suggests that obesity phenotype has significant impact on omental fat tissue characteristics which is related to the clinical course of EC and may have practical consequences.

Role of the PI3K-Akt Signaling Pathway in the Pathogenesis of Polycystic Ovary Syndrome

This review aimed to focus on the recent progress of the understanding of the role of phosphatidylinositol 3-kinase (PI3K) in polycystic ovary syndrome (PCOS). In recent years, it has been increasingly recognized that PI3K plays an important role in PCOS whose pathogenesis is unclear. However, research continues into revealing the details of how PI3Ks are involved in developing PCOS. Previous studies have shown that activation of the PI3K-protein kinase B (Akt) signaling pathway has important effects on insulin resistance and endometrial cancer. Knowledge of the action of PI3K in PCOS might provide valuable information to further validate the pathogenesis of PCOS and suggest new methods of treatment.

The Obesity Paradox in Cancer: a Review

There is a common perception that excess adiposity, commonly approximated by body mass index (BMI), is associated with reduced cancer survival. A number of studies have emerged challenging this by demonstrating that overweight and early obese states are associated with improved survival. This finding is termed the "obesity paradox" and is well recognized in the cardio-metabolic literature but less so in oncology. Here, we summarize the epidemiological findings related to the obesity paradox in cancer. Our review highlights that many observations of the obesity paradox in cancer reflect methodological mechanisms including the crudeness of BMI as an obesity measure, confounding, detection bias, reverse causality, and a specific form of the selection bias, known as collider bias. It is imperative for the oncologist to interpret the observation of the obesity paradox against the above methodological framework and avoid the misinterpretation that being obese might be "good" or "protective" for cancer patients.

Measuring the biological effect of presurgical metformin treatment in endometrial cancer

Background:

Preclinical studies in endometrial cancer (EC) show that metformin reduces cellular proliferation by PI3K-AKT-mTOR inhibition. We tested the hypothesis that short-term presurgical metformin reduces cellular proliferation in atypical endometrial hyperplasia (AEH) and endometrioid EC, and assessed the feasibility of using phosphorylated PI3K-AKT-mTOR proteins as tissue end points.

Methods:

Women with AEH or EC received metformin 850 mg twice a day or no drug in the presurgical window between diagnosis and hysterectomy. Before and after the window, tissue samples were obtained; serum markers of insulin resistance (e.g. homeostasis model of assessment of insulin resistance index) were determined; and anthropometrics measured (e.g. BMI). Cell proliferation (Ki-67) and PI3K-AKT-mTOR phosphostatus were assessed by immunohistochemistry and scored blinded to treatment.

Results:

Twenty-eight metformin-treated and 12 untreated patients, well matched for age and BMI, completed the study. Metformin treatment (median 20 days, range 7–34) was associated with a 17.2% reduction in tumour Ki-67 (95% CI −27.4, −7.0, P=0.002), in a dose-dependent manner. Tumour PI3K-AKT-mTOR protein phosphostatus varied but the effects were not significant after adjusting for changes in controls.

Conclusions:

Short-term metformin was associated with reduced Ki-67 expression in EC. Changes in tumour PI3K-AKT-mTOR protein phosphostatus were seen in both groups. Future studies should address the variability attributed to different sampling techniques including devascularisation of the uterus at hysterectomy.

Insulinemia, heterogeneity of obesity and the risk of different types of endometrial cancer: existing evidence

Due to a number of reasons, endometrial cancer is a point of interest not only for oncologists, but also for a variety of specialists - especially endocrinologists. The endocrinology of endometrial cancer can be firmly divided into two categories - steroid and non-steroid. The steroid approach dominated during several decades due to hyperestrogenization signs observed in some patients. The balance was only regained in the last 15 years, when the role of diabetes and insulin resistance began to draw attention. This review aims to provide an update on connections between insulinemia (insulin resistance) and different obesity phenotypes as well to discuss their relation to development of endometrial cancer, its clinical-morphological features and the increasing number of its molecular-biological subtypes.

Features of endometrial cancer in patients with 'metabolically healthy' versus 'standard' obesity: the decreasing frequency of metabolically healthy obesity

Background:

As endometrial cancer (EC) prevalence increases with obesity, we aimed to determine whether EC characteristics depend upon obesity type: ‘standard’ (SO) or ‘metabolically healthy obesity’ (MHO).

Patients & methods:

258 EC patients were included. Data on anthropometry, blood hormones, lipids and glucose, and tumor features were collected.

Results:

EC clinicopathologic characteristics and clinical stage correlate differently with BMI and obesity type. BMI is related inversely with tumor grade while SO patients are characterized by a more advanced clinical stage than those with MHO. Besides typical insulin resistance signs, EC patients with SO often display a higher serum leptin/adiponectin ratio compared with MHO patients. Historical data suggest a gradual increase in EC patient height and weight, and a decrease in MHO prevalence.

Conclusion:

It is currently unknown whether the latter observation reflects the evolution of EC, or obesity alongside the current epidemic. Regardless, the reduced MHO prevalence demonstrates the need for more intensive preventive measures aimed at obesity and obesity-associated conditions, including different EC subtypes.

Worldwide prevalence of uterine body or endometrial cancer (EC) has increased notably. Recently, the WHO documented an obesity epidemic in several countries. Concurrently, many studies showed a high (37–66%) obesity rate in EC patients. There is currently no mention of a potentially distinctive correlation of EC with obesity types. In general, these types of obesity can be subdivided into ‘standard’ (SO; with metabolic disturbances, initially with insulin resistance signs) and ‘nonstandard’, or metabolically healthy obesity (MHO; without mentioned disturbances). The present paper concludes, first, that EC patients with SO (especially if BMI is ≥30) generally have more advanced tumor stage than patients with MHO. Second, in an EC group (2012–2014) a decrease in MHO frequency versus 1998–2000 group was observed. Altogether, this underlines the need for additional cancer preventive efforts in the obese female population.

Body mass index and mortality in endometrial cancer: A systematic review and meta-analysis

OBJECTIVE

To evaluate the association between body mass index (BMI) and mortality in women with endometrial cancer.

METHODS

A systematic review was performed utilizing a Medline search with Mesh keywords 'endometrial neoplasms' and ('body mass index' or 'obesity') and ('survival analysis' or 'mortality' or 'survivor' or 'survival') for studies published prior to June 2013. Inclusion criteria included studies that assessed associations between BMI and survival in endometrial cancer patients. Two investigators independently reviewed the title and abstract and full-text of articles for inclusion or exclusion decision; discordant decisions were adjudicated by a third reviewer. A random-effects model was constructed that was comparable to the standard random-effects models used in the meta-analysis of odds ratios. The model was fitted using SAS PROC NLMIXED.

RESULTS

1451 studies were identified and reviewed in duplicate, 18 met inclusion criteria. A random-effects meta-analysis demonstrated significantly higher odds of mortality with increasing BMI in endometrial cancer patients. Specifically the odds ratios were 1.01, 1.17, 1.26, and 1.66 for BMI categories of 25-29.9, 30-34.9, 35-39.9, and 40+, respectively. The odds ratio for all-cause mortality in endometrial cancer patients with a BMI≥40 compared to those with a BMI<25 was 1.66 (CI: 1.10-2.51, p=0.02). A single dose-response model indicated that a 10% increase in BMI resulted in a 9.2% increase in the odds of all-cause mortality (p=0.007).

CONCLUSION

Increased BMI is significantly associated with increased all-cause mortality in women with endometrial cancer, with the highest risk for those with a BMI≥40.

PTEN loss is a context-dependent outcome determinant in obese and non-obese endometrioid endometrial cancer patients

Endometrial cancer incidence is increasing, due in part to a strong association with obesity. Mutations in the phosphatidylinositol 3-kinase (PI3K) pathway, the central relay pathway of insulin signals, occur in the majority of endometrioid adenocarcinomas, the most common form of endometrial cancer. We sought to determine the impact of PI3K pathway alterations on progression free survival in a cohort of endometrioid endometrial cancers. Prognostic utility of PIK3CA, PIK3R1, and PTEN mutations, as well as PTEN protein loss by immunohistochemistry, was explored in the context of patient body mass index. Reverse-phase protein arrays were utilized to assess protein expression based on PTEN status. Among 187 endometrioid endometrial cancers, there were no statistically significant associations between PFS and PIK3CA, PIK3R1, PTEN mutation or loss. When stratified by body mass index, PTEN loss was associated with improved progression free survival (P < 0.006) in obese (body mass index ≥ 30) patients. PTEN loss resulted in distinct protein changes: Canonical PI3K pathway activation was observed only in the non-obese population while decreased expression of β-CATENIN and phosphorylated FOXO3A was observed in obese patients. These data suggest the impact of PTEN loss on tumor biology and clinical outcomes must be interpreted in the context of body mass index, and provide a potential explanation for discrepant reports on the effect of PTEN status and obesity on prognosis in endometrial cancer. This reveals a clinically important interaction between metabolic state and tumor genetics that may unveil the biologic underpinning of obesity-related cancers and impact ongoing clinical trials with PI3K pathway inhibitors.

Lymphadenectomy for the management of endometrial cancer

BACKGROUND

This is an update of a previous Cochrane review published in Issue 1, 2010. The role of lymphadenectomy in surgical management of endometrial cancer remains controversial. Lymph node metastases can be found in approximately 10% of women who clinically before surgery have cancer confined to the womb. Removal of all pelvic and para-aortic lymph nodes (lymphadenectomy) at initial surgery has been widely advocated, and pelvic and para-aortic lymphadenectomy remains part of the FIGO (International Federation of Gynaecology and Obstetrics) staging system for endometrial cancer. This recommendation is based on data from studies that suggested improvement in survival following pelvic and para-aortic lymphadenectomy. However, these studies were not randomised controlled trials (RCTs), and treatment of pelvic lymph nodes may not confer a direct therapeutic benefit, other than allocating women to poorer prognosis groups. Furthermore, the Cochrane review and meta-analysis of RCTs of routine adjuvant radiotherapy to treat possible lymph node metastases in women with early-stage endometrial cancer found no survival advantage. Surgical removal of pelvic and para-aortic lymph nodes has serious potential short-term and long-term sequelae. Therefore it is important to investigate the clinical value of this treatment.

OBJECTIVES

To evaluate the effectiveness and safety of lymphadenectomy for the management of endometrial cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Gynaecological Cancer Review Group Trials Register, MEDLINE and EMBASE to June 2009 for the original review and extended the search to June 2015 for this version of the review. We also searched registers of clinical trials, abstracts of scientific meetings and reference lists of included studies, and we contacted experts in the field.

SELECTION CRITERIA

RCTs and quasi-RCTs that compared lymphadenectomy versus no lymphadenectomy in adult women diagnosed with endometrial cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias. Hazard ratios (HRs) for overall and progression-free survival and risk ratios (RRs) comparing adverse events in women who received lymphadenectomy versus those with no lymphadenectomy were pooled in random-effects meta-analyses. We assessed the quality of the evidence using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach.

MAIN RESULTS

Three RCTs met the inclusion criteria; for one small RCT, data were insufficient for inclusion in the meta-analysis. The two RCTs included in the analysis randomly assigned 1945 women, reported HRs for survival adjusted for prognostic factors and based on 1851 women and had an overall low risk of bias, as they satisfied four of the assessment criteria. The third study had an overall unclear risk of bias, as information provided was not adequate concerning random sequence generation, allocation concealment, blinding or completeness of outcome reporting.Results of the meta-analysis remain unchanged from the previous version of this review and indicate no differences in overall and recurrence-free survival between women who underwent lymphadenectomy and those who did not undergo lymphadenectomy (pooled HR 1.07, 95% CI 0.81 to 1.43; HR 1.23, 95% CI 0.96 to 1.58 for overall and recurrence-free survival, respectively) (1851 participants, two studies; moderate-quality evidence).We found no difference in risk of direct surgical morbidity between women who underwent lymphadenectomy and those who did not undergo lymphadenectomy. However, women who underwent lymphadenectomy had a significantly higher risk of surgery-related systemic morbidity and lymphoedema/lymphocyst formation than those who did not undergo lymphadenectomy (RR 3.72, 95% CI 1.04 to 13.27; RR 8.39, 95% CI 4.06 to 17.33 for risk of surgery-related systemic morbidity and lymphoedema/lymphocyst formation, respectively) (1922 participants, two studies; high-quality evidence).

AUTHORS' CONCLUSIONS

This review found no evidence that lymphadenectomy decreases risk of death or disease recurrence compared with no lymphadenectomy in women with presumed stage I disease. Evidence on serious adverse events suggests that women who undergo lymphadenectomy are more likely to experience surgery-related systemic morbidity or lymphoedema/lymphocyst formation. Currently, no RCT evidence shows the impact of lymphadenectomy in women with higher-stage disease and in those at high risk of disease recurrence.

Concise review: The obesity cancer paradigm: exploration of the interactions and crosstalk with adipose stem cells

With the recognition of obesity as a global health crisis, researchers have devoted greater effort to defining and understanding the pathophysiological molecular pathways regulating the biology of adipose tissue and obesity. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, has been linked to an increased incidence and aggressiveness of colon, hematological, prostate, and postmenopausal breast cancers. The increased morbidity and mortality of obesity-associated cancers have been attributed to higher levels of hormones, adipokines, and cytokines secreted by the adipose tissue. The increased amount of adipose tissue also results in higher numbers of adipose stromal/stem cells (ASCs). These ASCs have been shown to impact cancer progression directly through several mechanisms, including the increased recruitment of ASCs to the tumor site and increased production of cytokines and growth factors by ASCs and other cells within the tumor stroma. Emerging evidence indicates that obesity induces alterations in the biologic properties of ASCs, subsequently leading to enhanced tumorigenesis and metastasis of cancer cells. This review will discuss the links between obesity and cancer tumor progression, including obesity-associated changes in adipose tissue, inflammation, adipokines, and chemokines. Novel topics will include a discussion of the contribution of ASCs to this complex system with an emphasis on their role in the tumor stroma. The reciprocal and circular feedback loop between obesity and ASCs as well as the mechanisms by which ASCs from obese patients alter the biology of cancer cells and enhance tumorigenesis will be discussed.

Associations between etiologic factors and mortality after endometrial cancer diagnosis: the NRG Oncology/Gynecologic Oncology Group 210 trial

BACKGROUND

Few studies have analyzed relationships between risk factors for endometrial cancer, especially with regard to aggressive (non-endometrioid) histologic subtypes, and prognosis. We examined these relationships in the prospective NRG Oncology/Gynecologic Oncology Group 210 trial.

METHODS

Prior to surgery, participants completed a questionnaire assessing risk factors for gynecologic cancers. Pathology data were derived from clinical reports and central review. We used the Fine and Gray subdistribution hazards model to estimate subhazard ratios (HRs) and 95% confidence intervals (CIs) for associations between etiologic factors and cause-specific subhazards in the presence of competing risks. These models were stratified by tumor subtype and adjusted for stage and socioeconomic status indicators.

RESULTS

Median follow-up was 60months after enrollment (range: 1day-118months). Among 4609 participants, a total of 854 deaths occurred, of which, 582 deaths were attributed to endometrial carcinoma. Among low-grade endometrioid cases, endometrial carcinoma-specific subhazards were significantly associated with age at diagnosis (HR=1.04, 95% CI=1.01-1.06 per year, P-trend) and BMI (class II obesity vs. normal BMI: HR=2.29, 95% CI=1.06-4.98, P-trend=0.01). Among high-grade endometrioid cases, endometrial carcinoma-specific subhazards were associated with age at diagnosis (HR=1.05, 95% CI=1.02-1.07 per year, P-trend<0.001). Among non-endometrioid cases, endometrial carcinoma-specific subhazards were associated with parity relative to nulliparity among serous (HR=0.55, 95% CI=0.36-0.82) and carcinosarcoma cases (HR=2.01, 95% CI=1.00-4.05).

DISCUSSION

Several endometrial carcinoma risk factors are associated with prognosis, which occurs in a tumor-subtype specific context. If confirmed, these results would suggest that factors beyond histopathologic features and stage are related to prognosis. ClinicalTrials.gov Identifier: NCT00340808.

Polycystic ovary syndrome and risk of endometrial cancer: a mini-review

The polycystic ovary syndrome is the most common endocrinological disorder of reproductive age women with a prevalence of 5 to 8 %. The most common diagnostic criteria used for polycystic ovary syndrome are oligo- or an-ovulation, clinical and/ or biochemical signs of hyperandrogenism and polycystic ovaries. Hyperandrogenism results in increased estrogen levels and lack of cyclic progesterone due to anovulation and persistent stimulation of the endometrium may lead to endometrial hyperplasia or adenocarcinoma development. In this mini review, we aimed to evaluate the possible relationship between polycystic ovary syndrome and endometrial cancer.

Radiation-Associated Toxicities in Obese Women with Endometrial Cancer: More Than Just BMI?

PURPOSE

The study characterizes the impact of obesity on postoperative radiation-associated toxicities in women with endometrial cancer (EC).

MATERIAL AND METHODS

A retrospective study identified 96 women with EC referred to a large urban institution's radiation oncology practice for postoperative whole pelvic radiotherapy (WPRT) and/or intracavitary vaginal brachytherapy (ICBT). Demographic and clinicopathologic data were obtained. Toxicities were graded according to RTOG Acute Radiation Morbidity Scoring Criteria. Follow-up period ranged from 1 month to 11 years (median 2 years). Data were analyzed by χ(2), logistic regression, and recursive partitioning analyses.

RESULTS

68 EC patients who received WPRT and/or ICBT were analyzed. Median age was 52 years (29-73). The majority were Hispanic (71%). Median BMI at diagnosis was 34.5 kg/m(2) (20.5-56.6 kg/m(2)). BMI was independently associated with radiation-related cutaneous (p = 0.022) and gynecologic-related (p = 0.027) toxicities. Younger women also reported more gynecologic-related toxicities (p = 0.039). Adjuvant radiation technique was associated with increased gastrointestinal- and genitourinary-related toxicities but not gynecologic-related toxicity.

CONCLUSIONS

Increasing BMI was associated with increased frequency of gynecologic and cutaneous radiation-associated toxicities. Additional studies to critically evaluate the radiation treatment dosing and treatment fields in obese EC patients are warranted to identify strategies to mitigate the radiation-associated toxicities in these women.