A high body mass index is not a worse prognostic factor for endometrial carcinoma in a predominantly obese population

Obesity paradox: is a high body mass index positively influencing survival outcomes in gynecological cancers? A systematic review and meta-analysis

OBJECTIVE

Obesity represents an exponentially growing preventable disease leading to different health complications, particularly when associated with cancer. In recent years, however, an 'obesity paradox' has been hypothesized where obese individuals affected by cancer counterintuitively show better survival rates. The aim of this systematic review and meta-analysis is to assess whether the prognosis in gynecological malignancies is positively influenced by obesity.

METHODS

This study adheres to PRISMA guidelines and is registered with PROSPERO. Studies reporting the impact of a body mass index (BMI) of >30 kg/m2 compared with <30 kg/m2 in patients with gynecological cancers listed in PubMed, Google Scholar and ClinicalTrials.gov were included in the analysis. The Quality Assessment of Diagnostic Accuracy Studies 2 tool (QUADAS-2) was used for quality assessment of the selected articles.

RESULTS

Twenty-one studies were identified for the meta-analysis, including 14 108 patients with cervical, ovarian, or endometrial cancer. There was no benefit in 5-year overall survival for obese patients compared with non-obese patients (OR 1.2, 95% CI 1.00 to 1.44, p=0.05; I2=71%). When pooling for cancer sub-groups, there were no statistically significant differences in 5-year overall survival in patients with cervical cancer and 5-year overall survival and progression-free survival in patients with ovarian cancer. For obese women diagnosed with endometrial cancer, a significant decrease of 44% in 5-year overall survival (p=0.01) was found, with no significant difference in 5-year disease-free survival (p=0.78).

CONCLUSION

According to the results of the present meta-analysis, a BMI of ≥30 kg/m2 does not have a positive prognostic effect on survival compared with a BMI of <30 kg/m2 in women diagnosed with gynecological cancers. The existence of the 'obesity paradox' in other fields, however, suggests the importance of further investigations with prospective studies.

Prediction of lymphovascular space invasion in endometrial cancer using the 55-gene signature selected by DNA microarray analysis

Lymphovascular space invasion (LVSI) is considered to be the beginning of lymphogenous and hematogenous metastases. It is strongly related to dissemination, and therefore could be a valuable predictive sign of lymph node metastases and distant spread. Recently, the presence of LVSI in endometrial cancer (EC) has been shown to be an independent prognostic factor. The preoperative diagnosis of LVSI by pathological examination is difficult and LVSI is detected after surgery. The aim of the current study was to explore candidate genes as potential diagnostic biomarkers and determine whether they are predictors of LVSI in patients with EC. A total of 88 surgical specimens obtained from EC patients who had undergone surgical resection at Fukushima Medical University Hospital between 2010 and 2015 were analyzed using DNA microarray. LVSI was significantly associated with poor prognostic factors in EC such as higher tumor grade, lymph node metastasis, deep myometrium invasion, advanced stage and recurrence. Fifty-five candidate genes were significantly differentially expressed between 26 LVSI-positive and 62 LVSI-negative samples. All 88 samples were divided into two groups according to hierarchical clustering of 55 genes. Regarding diagnostic accuracy, sensitivity and negative predictive value were both high (92% and 95%, respectively); further, specificity and positive predictive value were both moderate (63% and 71%, respectively). Our data suggests that the 55-gene signature could contribute to predicting LVSI in EC, and provide clinically important information for better management. The molecular signatures of 55 genes may be also useful for understanding the underlying mechanism of LVSI.

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.

Influence of Body Mass Index on Tumor Pathology and Survival in Uterine Cancer: A Danish Register Study

Objective

To evaluate the influence of body mass index (BMI) on endometrial tumor pathology, stage and complication rate and to identify individual prognostic factors, such as BMI, in types I and II endometrial cancer.

Design

Register study included all Danish women who underwent surgery for uterine cancer or atypical endometrial hyperplasia (International Classification of Diseases-10 codes D070, DC549) 2005 to 2012 (n = 6003).

Main Outcome Measures

Impact of BMI on type I and II endometrial cancer survival.

Materials and Methods

Danish Gynecological Cancer Database data on women with type I and II endometrial cancer were retrieved. Kaplan-Meier plot was used to illustrate differences in survival in relation to BMI. Log-rank test was used to demonstrate difference between the curves. Cox regression hazard model was used to estimate hazard ratios (HR) of the effect of BMI on overall survival.

Results

Four thousand three hundred thirty women were included. Women with type I cancer had a significantly better overall survival compared with those with type II cancer. Low BMI was associated with increased mortality in type I (HR, 2.07; 95% confidence interval [CI], 1.20–3.55), whereas in type II both low (HR, 1.68; 95% CI, 1.03–2.74) and high BMI (BMI, 30–35: HR, 1.54; 95% CI, 1.01–2.26 and BMI >40: HR, 2.15; 95% CI, 1.12–4.11) were significantly associated with increased mortality.

Conclusion

Abnormal BMI is associated with increased mortality in subtypes of endometrial cancer. Underweight was associated with increased overall mortality in both types I and II, whereas obesity only disclosed a significant impact on overall mortality in type II.

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.

[Influence of Body Mass Index on management and prognosis of women with endometrial cancer]

OBJECTIVE

The aim of this study was to evaluate the outcome of surgery, postoperative morbidity and prognosis of patients with endometrial cancer in function of the body mass index (BMI).

PATIENTS AND METHODS

The study cohort consisted of consecutive women undergoing surgery for endometrial cancer in our institution between January 2000, and September 2012. Individual records of all patients were reviewed and analyzed. Patient BMI was categorized as underweight, normal, overweight and obese.

RESULTS

A total of 192 patients were evaluated. Patients were followed for one to 153months with a mean of 52.56months. The mean BMI and the range of each of the BMI categories were 16.97kg/m(2) (14-18), 22.97kg/m(2) (20-24.9), 27.61kg/m(2) (25.7-29.4), 37.34kg/m(2) (30-71). Women with higher BMI were more frequently affected by hypertension (8.3%, 31.43%, 58.13% and 59.7% respectively, P<0.0001) and diabetes (16.67%, 4.3%, 13.9% and 29.85% respectively, P=0.02). Women with normal BMI had more frequently postmenopausal replacement therapy than the other categories (P=0.0004). Surgical operative time, mean length of hospitalization in days were not significantly different among the 4 groups. In the obese group there were significantly higher peroperative blood loss (P=0.01), more wound abces (P=0.05), more eventration (P=0.02) and more reinterventions for complications (P=0.03). Patients had the same protocols of treatment (surgery and adjuvant treatment) and histological characteristics were the same between groups but obese patients had much less positive lymph nodes (P=0.03). There were no statistically significant difference in overall 5-years survival between groups (P=0.54) DISCUSSION AND CONCLUSIONS: Our study demonstrate a survival equivalency for obese and non-obese women even though obese women showed less positive lymph nodes.