Disease-free survival as a surrogate for overall survival in neoadjuvant trials of gastroesophageal adenocarcinoma: Pooled analysis of individual patient data from randomized controlled trials

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Background: Disease-free survival (DFS) is an appealing surrogate endpoint for overall survival (OS) in trials on neoadjuvant or adjuvant cancer therapy, because it is available faster and with less follow-up effort. The aim of this study was to assess if DFS can be a valid surrogate endpoint for OS when comparing neoadjuvant treatment followed by surgery to surgery alone for gastroesophageal adenocarcinoma. Methods: Individual patient data (IPD) from eight randomized controlled trials (n = 1,126 patients) which compared neoadjuvant therapy followed by surgery with surgery alone for gastroesophageal adenocarcinoma were used for the analysis. Correlation between OS-time and DFS-time was calculated. Kaplan-Meier survival curves and corresponding hazard ratios (HRs) for treatment effects were separately determined for each trial. Subsequently, HRs were pooled in a meta-analysis using a random-effects model. An error-in-variables linear regression model was used to compare observed and predicted values. The minimum treatment effect on DFS necessary to predict a non-zero treatment effect on OS was estimated by calculating the surrogate threshold effect. Results: OS-time correlated strongly with DFS-time. HRs for OS and DFS were highly similar for all single trials. The meta-analysis yielded almost identical overall HRs for treatment effects on OS and DFS. The determination coefficient for the association between HRs for OS and DFS was 0.912 (95% confidence interval 0.75-1.0), indicating a strong trial-level surrogacy between OS and DFS. The surrogate threshold effect was calculated at 0.79, indicating that a future trial yielding a hazard ratio for the treatment effect on DFS < 0.79 could be expected with a 95% probability to yield a hazard ratio for the treatment effect on OS < 1. Conclusions: DFS and OS strongly correlate both after neoadjuvant therapy followed by surgery and after surgery alone for gastroesophageal adenocarcinoma. Likewise, the treatment effects on the two endpoints are very similar. Consequently, DFS can be regarded an appropriate surrogate endpoint for OS in trials on neoadjuvant therapy for gastroesophageal adenocarcinoma.

Predictors of overall and recurrence-free survival after neoadjuvant chemotherapy for gastroesophageal adenocarcinoma: Pooled analysis of individual patient data (IPD) from randomized controlled trials (RCTs)

BACKGROUND

Neoadjuvant chemotherapy improves prognosis of patients with locally advanced gastroesophageal adenocarcinoma. The aim of this study was to identify predictors for postoperative survival following neoadjuvant therapy. These could be useful in deciding about postoperative continuation of chemotherapy.

METHODS

This meta-analysis used IPD from RCTs comparing neoadjuvant chemotherapy with surgery alone for gastroesophageal adenocarcinoma. Trials providing IPD on age, sex, performance status, pT/N stage, resection status, overall and recurrence-free survival were included. Survival was calculated in the entire study population and subgroups stratified by supposed predictors and compared using the log-rank test. Multivariable Cox models were used to identify independent survival predictors.

RESULTS

Four RCTs providing IPD from 553 patients fulfilled the inclusion criteria. (y)pT and (y)pN stage and resection status strongly predicted postoperative survival both after neoadjuvant therapy and surgery alone. Patients with R1 resection after neoadjuvant therapy survived longer than those with R1 resection after surgery alone. Patients with stage pN0 after surgery alone had better prognosis than those with ypN0 after neoadjuvant therapy. Patients with stage ypT3/4 after neoadjuvant therapy survived longer than those with stage pT3/4 after surgery alone. Multivariable regression identified resection status and (y)pN stage as predictors of survival in both groups. (y)pT stage predicted survival only after surgery alone.

CONCLUSION

After neoadjuvant therapy for gastroesophageal adenocarcinoma, survival is determined by the same factors as after surgery alone. However, ypT stage is not an independent predictor. These results can facilitate the decision about postoperative continuation of chemotherapy in pretreated patients.

Person-directed, non-pharmacological interventions for sleepiness at work and sleep disturbances caused by shift work

BACKGROUND

Shift work is often associated with sleepiness and sleep disorders. Person-directed, non-pharmacological interventions may positively influence the impact of shift work on sleep, thereby improving workers' well-being, safety, and health.

OBJECTIVES

To assess the effects of person-directed, non-pharmacological interventions for reducing sleepiness at work and improving the length and quality of sleep between shifts for shift workers.

SEARCH METHODS

We searched CENTRAL, MEDLINE Ovid, Embase, Web of Knowledge, ProQuest, PsycINFO, OpenGrey, and OSH-UPDATE from inception to August 2015. We also screened reference lists and conference proceedings and searched the World Health Organization (WHO) Trial register. We contacted experts to obtain unpublished data.

SELECTION CRITERIA

Randomised controlled trials (RCTs) (including cross-over designs) that investigated the effect of any person-directed, non-pharmacological intervention on sleepiness on-shift or sleep length and sleep quality off-shift in shift workers who also work nights.

DATA COLLECTION AND ANALYSIS

At least two authors screened titles and abstracts for relevant studies, extracted data, and assessed risk of bias. We contacted authors to obtain missing information. We conducted meta-analyses when pooling of studies was possible.

MAIN RESULTS

We included 17 relevant trials (with 556 review-relevant participants) which we categorised into three types of interventions: (1) various exposures to bright light (n = 10); (2) various opportunities for napping (n = 4); and (3) other interventions, such as physical exercise or sleep education (n = 3). In most instances, the studies were too heterogeneous to pool. Most of the comparisons yielded low to very low quality evidence. Only one comparison provided moderate quality evidence. Overall, the included studies' results were inconclusive. We present the results regarding sleepiness below. Bright light Combining two comparable studies (with 184 participants altogether) that investigated the effect of bright light during the night on sleepiness during a shift, revealed a mean reduction 0.83 score points of sleepiness (measured via the Stanford Sleepiness Scale (SSS) (95% confidence interval (CI) -1.3 to -0.36, very low quality evidence). Another trial did not find a significant difference in overall sleepiness on another sleepiness scale (16 participants, low quality evidence).Bright light during the night plus sunglasses at dawn did not significantly influence sleepiness compared to normal light (1 study, 17 participants, assessment via reaction time, very low quality evidence).Bright light during the day shift did not significantly reduce sleepiness during the day compared to normal light (1 trial, 61 participants, subjective assessment, low quality evidence) or compared to normal light plus placebo capsule (1 trial, 12 participants, assessment via reaction time, very low quality evidence). Napping during the night shiftA meta-analysis on a single nap opportunity and the effect on the mean reaction time as a surrogate for sleepiness, resulted in a 11.87 ms reduction (95% CI 31.94 to -8.2, very low quality evidence). Two other studies also reported statistically non-significant decreases in reaction time (1 study seven participants; 1 study 49 participants, very low quality evidence).A two-nap opportunity resulted in a statistically non-significant increase of sleepiness (subjective assessment) in one study (mean difference (MD) 2.32, 95% CI -24.74 to 29.38, 1 study, 15 participants, low quality evidence). Other interventionsPhysical exercise and sleep education interventions showed promise, but sufficient data to draw conclusions are lacking.

AUTHORS' CONCLUSIONS

Given the methodological diversity of the included studies, in terms of interventions, settings, and assessment tools, their limited reporting and the very low to low quality of the evidence they present, it is not possible to determine whether shift workers' sleepiness can be reduced or if their sleep length or quality can be improved with these interventions.We need better and adequately powered RCTs of the effect of bright light, and naps, either on their own or together and other non-pharmacological interventions that also consider shift workers' chronobiology on the investigated sleep parameters.

Perioperative chemo(radio)therapy versus primary surgery for resectable adenocarcinoma of the stomach, gastroesophageal junction, and lower esophagus

BACKGROUND

The outcome of patients with locally advanced gastroesophageal adenocarcinoma (adenocarcinoma of the esophagus, gastroesophageal (GE) junction, and stomach) is poor. There is conflicting evidence regarding the effects of perioperative chemotherapy on survival and other outcomes.

OBJECTIVES

To assess the effect of perioperative chemotherapy for gastroesophageal adenocarcinoma on survival and other clinically relevant outcomes in the overall population of participants in randomized controlled trials (RCTs) and in prespecified subgroups.

SEARCH METHODS

We performed computerized searches in the Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Review of Effectiveness (DARE), the Cochrane Database of Systematic Reviews (CDSR) from The Cochrane Library, MEDLINE (1966 to May 2011), EMBASE (1980 to May 2011), and LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud), combining the Cochrane highly sensitive search strategy with specific search terms. Moreover, we handsearched several online databases, conference proceedings, and reference lists of retrieved papers.

SELECTION CRITERIA

We included RCTs which randomized patients with gastroesophageal adenocarcinoma, in the absence of distant metastases, to receive either chemotherapy with or without radiotherapy followed by surgery, or surgery alone.

DATA COLLECTION AND ANALYSIS

Two independent review authors identified eligible trials. We solicited individual patient data (IPD) from all selected trials. We performed meta-analyses based on intention-to-treat populations using the two-stage method to combine IPD with aggregate data from RCTs for which IPD were unavailable. We combined data from all trials providing IPD in a Cox proportional hazards model to assess the effect of several covariables on overall survival.

MAIN RESULTS

We identified 14 RCTs with 2422 eligible patients. For eight RCTs with 1049 patients (43.3%), we were able to obtain IPD. Perioperative chemotherapy was associated with significantly longer overall survival (hazard ratio (HR) 0.81; 95% confidence interval (CI) 0.73 to 0.89). This corresponds to a relative survival increase of 19% or an absolute survival increase of 9% at five years. This survival advantage was consistent across most subgroups. There was a trend towards a more pronounced treatment effect for tumors of the GE junction compared to other sites, and for combined chemoradiotherapy as compared to chemotherapy in tumors of the esophagus and GE junction. Resection with negative margins was a strong predictor of survival. Multivariable analysis showed that tumor site, performance status, and age have an independent significant effect on survival. Moreover, there was a significant interaction of the effect of perioperative chemotherapy with age (larger treatment effect in younger patients). Perioperative chemotherapy also showed a significant effect on several secondary outcomes. It was associated with longer disease-free survival, higher rates of R0 resection, and more favorable tumor stage upon resection, while there was no association with perioperative morbidity and mortality.

AUTHORS' CONCLUSIONS

Perioperative chemotherapy for resectable gastroesophageal adenocarcinoma increases survival compared to surgery alone. It should thus be offered to all eligible patients. There is a trend to a larger survival advantage for tumors of the GE junction as compared to other sites and for chemoradiotherapy as compared to chemotherapy in esophageal and GE junction tumors. Likewise, there is an interaction between age and treatment effect, with younger patients having a larger survival advantage, and no survival advantage for elderly patients.

Perioperative chemo(radio)therapy versus primary surgery for resectable adenocarcinoma of the stomach, gastroesophageal junction, and lower esophagus

BACKGROUND

The outcome of patients with locally advanced gastroesophageal adenocarcinoma (adenocarcinoma of the esophagus, gastroesophageal (GE) junction, and stomach) is poor. There is conflicting evidence regarding the effects of perioperative chemotherapy on survival and other outcomes.

OBJECTIVES

To assess the effect of perioperative chemotherapy for gastroesophageal adenocarcinoma on survival and other clinically relevant outcomes in the overall population of participants in randomized controlled trials (RCTs) and in prespecified subgroups.

SEARCH METHODS

We performed computerized searches in the Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Review of Effectiveness (DARE), the Cochrane Database of Systematic Reviews (CDSR) from The Cochrane Library, MEDLINE (1966 to May 2011), EMBASE (1980 to May 2011), and LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud), combining the Cochrane highly sensitive search strategy with specific search terms. Moreover, we handsearched several online databases, conference proceedings, and reference lists of retrieved papers.

SELECTION CRITERIA

We included RCTs which randomized patients with gastroesophageal adenocarcinoma, in the absence of distant metastases, to receive either chemotherapy with or without radiotherapy followed by surgery, or surgery alone.

DATA COLLECTION AND ANALYSIS

Two independent review authors identified eligible trials. We solicited individual patient data (IPD) from all selected trials. We performed meta-analyses based on intention-to-treat populations using the two-stage method to combine IPD with aggregate data from RCTs for which IPD were unavailable. We combined data from all trials providing IPD in a Cox proportional hazards model to assess the effect of several covariables on overall survival.

MAIN RESULTS

We identified 14 RCTs with 2422 eligible patients. For eight RCTs with 1049 patients (43.3%), we were able to obtain IPD. Perioperative chemotherapy was associated with significantly longer overall survival (hazard ratio (HR) 0.81; 95% confidence interval (CI) 0.73 to 0.89). This corresponds to a relative survival increase of 19% or an absolute survival increase of 9% at five years. This survival advantage was consistent across most subgroups. There was a trend towards a more pronounced treatment effect for tumors of the GE junction compared to other sites, and for combined chemoradiotherapy as compared to chemotherapy in tumors of the esophagus and GE junction. Resection with negative margins was a strong predictor of survival. Multivariable analysis showed that tumor site, performance status, and age have an independent significant effect on survival. Moreover, there was a significant interaction of the effect of perioperative chemotherapy with age (larger treatment effect in younger patients). Perioperative chemotherapy also showed a significant effect on several secondary outcomes. It was associated with longer disease-free survival, higher rates of R0 resection, and more favorable tumor stage upon resection, while there was no association with perioperative morbidity and mortality.

AUTHORS' CONCLUSIONS

Perioperative chemotherapy for resectable gastroesophageal adenocarcinoma increases survival compared to surgery alone. It should thus be offered to all eligible patients. There is a trend to a larger survival advantage for tumors of the GE junction as compared to other sites and for chemoradiotherapy as compared to chemotherapy in esophageal and GE junction tumors. Likewise, there is an interaction between age and treatment effect, with younger patients having a larger survival advantage, and no survival advantage for elderly patients.

Menopausal hormone therapy and risk of clinical breast cancer subtypes

BACKGROUND

Breast cancer is a heterogeneous disease with subtypes that may vary in their etiologies. Menopausal hormone therapy has been associated more strongly with lobular and tubular than ductal histologic types and with tumors that are smaller, hormone receptor-positive, and of lower grade. At the same time, correlations have been observed between histology and clinical characteristics. To identify those tumor subtypes most strongly associated with hormone therapy use, it is necessary to disentangle these interrelationships.

METHODS

Based on 3,464 postmenopausal breast cancer cases and 6,657 controls from the population-based Mammary carcinoma Risk factor Investigation study, we used polytomous logistic regression to evaluate associations between hormone therapy use and risk of invasive breast cancer subtypes. We assessed variations in risk for selected tumor characteristics among histologic and hormone receptor subtypes, both overall and for specific hormone therapy regimens.

RESULTS

Lobular and mixed types showed less variation by prognostic factors than did ductal tumors. Current hormone therapy use had the strongest associations with prognostic variables in estrogen receptor (ER)-positive and/or progesterone receptor (PR)-positive ductal tumors and in lobular tumors regardless of ER/PR status, with little effect on ER/PR-negative ductal tumors. The observed associations varied minimally by hormone therapy type or regimen.

CONCLUSION

Current hormone therapy use was associated with more favorable breast cancer characteristics for ductal tumors but had less effect on prognostic characteristics in women with lobular tumors. Both histologic type and estrogen receptor/progesterone receptor status seem to be important in explaining the role of hormone therapy in the etiology of breast cancer subtypes.

Manganese superoxide dismutase Ala-9Val polymorphism, environmental modifiers, and risk of breast cancer in a German population

OBJECTIVE

A functional polymorphism at codon 16 (Alanine-to-Valine) of manganese superoxide dismutase (MnSOD) has been hypothesized to increase the risk of breast cancer and to modify the effects of oxidative stress. However, study findings have been inconsistent and sample sizes often small.

METHODS

We used a large population-based age-matched case-control study in German Caucasian women up to age 50 to assess breast cancer risk associated with this polymorphism and to investigate interaction with other known risk factors related to oxidative stress, including alcohol intake, cigarette smoking, and diet. Data on a total of 614 cases and 1,080 controls were evaluated using multivariate conditional logistic models.

RESULTS

No main effect between genotype and breast cancer was observed. However, risk was significantly increased for Ala carriers who consumed > or =19 g of alcohol per day, compared to women homozygous for the Val allele who did not drink (OR 2.1, 95% CI 1.1-3.9; p = 0.13 for interaction). No significant effect modification was observed for smoking or diet.

CONCLUSIONS

The MnSOD Ala-9Val polymorphism may contribute to an increase in breast cancer risk in the context of high alcohol consumption, however the polymorphism is not an overall risk factor for breast cancer in this primarily premenopausal population.

The association between female genital cutting and correlates of sexual and gynaecological morbidity in Edo State, Nigeria

OBJECTIVE

To examine the association between female genital cutting and frequency of sexual and gynaecological symptoms among a cohort of cut versus uncut women in Edo State of Nigeria.

DESIGN

Cross sectional study.

SETTING

Women attending family planning and antenatal clinics at three hospitals in Edo State, South-south Nigeria.

POPULATION

1836 healthy premenopausal women.

METHODS

The sample included 1836 women. Information about type of female genital cutting was based on medical exams while a structured questionnaire was used to elicit information on the women's sociodemographic characteristics, their ages of first menstruation (menarche), first intercourse, marriage and pregnancy, sexual history and experiences of symptoms of reproductive tract infections. Associations between female genital cutting and these correlates of sexual and gynaecologic morbidity were analysed using univariate and multivariate logistic regression and Cox models.

MAIN OUTCOME MEASURES

Frequency of self-reported orgasm achieved during sexual intercourse and symptoms of reproductive tract infections.

RESULTS

Forty-five percent were circumcised and 71% had type 1, while 24% had type 2 female genital cutting. No significant differences between cut and uncut women were observed in the frequency of reports of sexual intercourse in the preceding week or month, the frequency of reports of early arousal during intercourse and the proportions reporting experience of orgasm during intercourse. There was also no difference between cut and uncut women in their reported ages of menarche, first intercourse or first marriage in the multivariate models controlling for the effects of socio-economic factors. In contrast, cut women were 1.25 times more likely to get pregnant at a given age than uncut women. Uncut women were significantly more likely to report that the clitoris is the most sexually sensitive part of their body (OR = 0.35, 95% CI = 0.26-0.47), while cut women were more likely to report that their breasts are their most sexually sensitive body parts (OR = 1.91; 95% CI = 1.51-2.42). Cut women were significantly more likely than uncut women to report having lower abdominal pain (OR = 1.54, 95% CI = 1.11-2.14), yellow bad-smelling vaginal discharge (OR = 2.81, 95% CI = 1.54-5.09), white vaginal discharge (OR = 1.65, 95% CI = 1.09-2.49) and genital ulcers (OR = 4.38, 95% CI 1.13-17.00).

CONCLUSION

Female genital cutting in this group of women did not attenuate sexual feelings. However, female genital cutting may predispose women to adverse sexuality outcomes including early pregnancy and reproductive tract infections. Therefore, female genital cutting cannot be justified by arguments that suggest that it reduces sexual activity in women and prevents adverse outcomes of sexuality.

The impact of female genital cutting on first delivery in southwest Nigeria

To date, data linking obstetric morbidity to female genital cutting in populations with less severe types of cutting have been limited to case reports and speculation. In this cross-sectional study, 1,107 women at three hospitals in Edo State, Nigeria, reported on their first-delivery experiences. Fifty-six percent of the sample had undergone genital cutting. Although univariate analyses suggest that genital cutting is associated with delivery complications and procedures, multivariate analyses controlling for sociodemographic factors and delivery setting show no difference between cut and noncut women's likelihood of reporting first-delivery complications or procedures. Whereas a clinical association between genital cutting and obstetric morbidity may occur in populations that have undergone more severe forms of cutting, in this setting, apparent associations between cutting and obstetric morbidity appear to reflect confounding by social class and by the conditions under which delivery takes place.

Female genital cutting in southern urban and peri-urban Nigeria: self-reported validity, social determinants and secular decline

Despite growing public resistance to the practice of female genital cutting (FGC), documentation of its prevalence, social correlates or trends in practice are extremely limited, and most available data are based on self-reporting. In three antenatal and three family planning clinics in South-west Nigeria we studied the prevalence, social determinants, and validity of self-reporting for FGC among 1709 women. Women were interviewed on social and demographic history, and whether or not they had undergone FGC. Interviews were followed by clinical examination to affirm the occurrence and extent of circumcision. In total, 45.9% had undergone some form of cutting. Based on WHO classifications by type, 32.6% had Type I cuts, 11.5% Type II, and 1.9% Type III or IV. Self-reported FGC status was valid in 79% of women; 14% were unsure of their status, and 7% reported their status incorrectly. Women are more likely to be unsure of their status if they were not cut, or come from social groups with a lower prevalence of cutting. Ethnicity was the most significant social predictor of FGC, followed by age, religious affiliation and education. Prevalence of FGC was highest among the Bini and Urhobo, among those with the least education, and particularly high among adherents to Pentecostal churches; this was independent of related social factors. There is evidence of a steady and steep secular decline in the prevalence of FGC in this region over the past 25 years, with age-specific prevalence rates of 75.4% among women aged 45-49 years, 48.6% among 30-34-year olds, and 14.5% among girls aged 15-19. Despite wide disparities in FGC prevalence across ethnic, religious and educational groups, the secular decline is evident among all social subgroups.