The Effects of Surgery Type and Chemotherapy on Early-Stage Breast Cancer Patients' Quality of Life Over 2-Year Follow-up

Factors Associated with Poor Quality of Life in Breast Cancer Survivors: A 3-Year Follow-Up Study

The purpose of this study was to identify subgroups of quality of life (QOL) changes in breast cancer survivors (BCSs), and to determine factors associated with subgroups of consistently low or deteriorated QOL. We enrolled 101 women recently diagnosed with breast cancer in South Korea and asked them to complete a questionnaire at baseline (within 1 month of diagnosis), 1 year later (Year 1), 2 years later (Year 2), and 3 years later (Year 3). We assessed QOL using the global QOL subscale from the EORTC QLQ-C30. We defined low QOL as a global QOL score 10 points below the mean score of the general population. Based on low QOL as defined in this study, we identified subgroups of QOL changes over 3 years. We identified four subgroups of QOL changes: improved (47.4%), stable (30%), continuously low (8.8%), and deteriorated (13.8%), and considered the last two categories (22.6%) poor QOL. Logistic regression analyses demonstrated that significant determinants of poor QOL were insomnia at Year 1, fatigue and anxiety at Year 2, and fatigue, depression, and comorbidity at Year 3. In conclusion, persistent symptoms of insomnia, fatigue, anxiety, depression, and comorbidity are potential risk factors for poor QOL in BCSs.

The Effectiveness of an Upper Limb Rehabilitation Program on Quality of Life in Breast Cancer Patients after Mastectomy: A Randomized Controlled Trial

OBJECTIVE

This study aims to investigate the effectiveness of an upper limb rehabilitation program on the quality of life in patients who had been first diagnosed breast cancer and subsequently underwent mastectomy.

DATA SOURCES

This randomized controlled trial enrolled 48 breast cancer patients who underwent mastectomy at a medical center in Taiwan. The patients were randomly assigned to either the intervention group (n = 24) or control group (n = 24). The patients in the intervention group participated in a 12-week upper limb rehabilitation program involving face-to-face upper limb rehabilitation education and once-a month monitoring of their upper extremity activity. The control group received standard nursing care. Quality of life was assessed through EORTC QLQ-C30 and QLQ-BR 23 questionnaires at baseline and weeks 4, 8, and 12 after enrollment.

RESULTS

Both the intervention and control groups had significantly improved their levels of functioning, symptoms, and quality of life from baseline to week 12 after enrollment. The intervention group showed greater improvements in functioning and symptom levels after the intervention compared to the control group; however, no statistically significant differences were found. Additionally, the levels of global health status/quality of life in both groups gradually increased from baseline to week 12 CONCLUSION: An upper limb rehabilitation program is effective in improving the functioning and symptoms of breast cancer patients who have undergone mastectomy.

IMPLICATIONS FOR NURSING PRACTICE

Patients are encouraged to undergo upper limb rehabilitation in order to improve their functioning, symptoms and quality of life.

A Comparison of Spectroscopy and Imaging Techniques Utilizing Spectrally Resolved Diffusely Reflected Light for Intraoperative Margin Assessment in Breast-Conserving Surgery: A Systematic Review and Meta-Analysis

Up to 19% of patients require re-excision surgery due to positive margins in breast-conserving surgery (BCS). Intraoperative margin assessment tools (IMAs) that incorporate tissue optical measurements could help reduce re-excision rates. This review focuses on methods that use and assess spectrally resolved diffusely reflected light for breast cancer detection in the intraoperative setting. Following PROSPERO registration (CRD42022356216), an electronic search was performed. The modalities searched for were diffuse reflectance spectroscopy (DRS), multispectral imaging (MSI), hyperspectral imaging (HSI), and spatial frequency domain imaging (SFDI). The inclusion criteria encompassed studies of human in vivo or ex vivo breast tissues, which presented data on accuracy. The exclusion criteria were contrast use, frozen samples, and other imaging adjuncts. 19 studies were selected following PRISMA guidelines. Studies were divided into point-based (spectroscopy) or whole field-of-view (imaging) techniques. A fixed-or random-effects model analysis generated pooled sensitivity/specificity for the different modalities, following heterogeneity calculations using the Q statistic. Overall, imaging-based techniques had better pooled sensitivity/specificity (0.90 (CI 0.76-1.03)/0.92 (CI 0.78-1.06)) compared with probe-based techniques (0.84 (CI 0.78-0.89)/0.85 (CI 0.79-0.91)). The use of spectrally resolved diffusely reflected light is a rapid, non-contact technique that confers accuracy in discriminating between normal and malignant breast tissue, and it constitutes a potential IMA tool.

The combined effect of dichloroacetate and 3-bromopyruvate on glucose metabolism in colorectal cancer cell line, HT-29; the mitochondrial pathway apoptosis

Background

5-Fluorouracil (5-FU) is regarded as the first line treatment for colorectal cancer; however, its effectiveness is limited by drug resistance. The ultimate goal of cancer therapy is induction of cancer cell death to achieve an effective outcome with minimal side effects. The present work aimed to assess the anti-cancer activities of mitocans which can be considered as an effective anticancer drug due to high specificity in targeting cancer cells.

Methods

MTT (3–4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) assay was performed to determine the effects of our mitocans on cell viability and cell death. Apoptosis and necrosis, caspase 3 activity, mitochondrial membrane potential and ROS production in HT29 cell lines were analyzed by ApopNexin™ FITC/PI Kit, Caspase- 3 Assay Kit, MitoTracker Green and DCFH-DA, respectively. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression level of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) genes in HT29 cell lines.

Results

Treatment with mitocans (3Br-P + DCA) inhibited the growth of HT29. Moreover, 3Br-P + DCA significantly induced apoptosis and necrosis, activation of caspase 3 activity, depolarize the mitochondrial membrane potential, and ROS production. At a molecular level, 3Br-P + DCA treatment remarkably down-regulated the expression of Bcl-2, while up-regulated the expression of Bax.

Conclusion

Mitocans, in particular the combined drug, 3Br-P + DCA, could be regarded and more evaluated as a safe and effective compound for CRC treatment. Targeting hexokinase and pyruvate dehydrogenase kinase enzymes may be an option to overcome 5-FU -mediated chemo-resistant in colorectal cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08564-3.

Fluorescence/photoacoustic imaging-guided nanomaterials for highly efficient cancer theragnostic agent

Imaging modalities combined with a multimodal nanocomposite contrast agent hold great potential for significant contributions in the biomedical field. Among modern imaging techniques, photoacoustic (PA) and fluorescence (FL) imaging gained much attention due to their non-invasive feature and the mutually supportive characteristic in terms of spatial resolution, penetration depth, imaging sensitivity, and speed. In this present study, we synthesized IR783 conjugated chitosan-polypyrrole nanocomposites (IR-CS-PPy NCs) as a theragnostic agent used for FL/PA dual-modal imaging. A customized FL and photoacoustic imaging system was constructed to perform required imaging experiments and create high-contrast images. The proposed nanocomposites were confirmed to have great biosafety, essentially a near-infrared (NIR) absorbance property with enhanced photostability. The in vitro photothermal results indicate the high-efficiency MDA-MB-231 breast cancer cell ablation ability of IR-CS-PPy NCs under 808 nm NIR laser irradiation. The in vivo PTT study revealed the complete destruction of the tumor tissues with IR-CS-PPy NCs without further recurrence. The in vitro and in vivo results suggest that the demonstrated nanocomposites, together with the proposed imaging systems could be an effective theragnostic agent for imaging-guided cancer treatment.

Effects of Chemotherapy-Induced Peripheral Neuropathy in Women With Breast Cancer: A Structural Equation Approach With the Theory of Unpleasant Symptoms

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common neurotoxic effect. Chemotherapy-induced peripheral neuropathy symptoms have multidimensional characteristics that are associated with various physiologic, psychological, and situational factors and affect individual's abilities to effectively function in performing daily tasks. The theory of unpleasant symptoms mediates the relationships among CIPN symptom experience, reduced performance in daily tasks, and causative factors.

OBJECTIVES

The aim of this study was to examine how influencing factors (physiologic, psychological, and situational) affect CIPN symptoms and the impact of symptom experience on functional interference in daily activities of chemotherapy-treated breast cancer survivors.

METHODS

A cross-sectional survey about causative factors, CIPN symptoms, and functional interference was completed by 190 women treated with adjuvant chemotherapy for nonmetastatic breast cancer. The hypothetical model was tested using structural equation modeling analysis.

RESULTS

The proposed model provided a good fit to the data. Physiologic and psychological factors accounted for 25.5% of the variance in CIPN symptom experience and explained 37.1% of the variance interfering with functional performance through CIPN symptom experience.

CONCLUSION

Disease- and treatment-related physiologic factors and coexisting psychological distress play crucial roles in explaining CIPN symptom experience and daily function in breast cancer survivors.

IMPLICATIONS FOR PRACTICE

The findings help healthcare professionals to improve long-term care for breast cancer survivors in terms of education for self-monitoring, coping, and establishing supportive environment that can contribute to reducing the unmet needs and interference associated with persistent CIPN.

Congruence and trajectories of device-measured and self-reported physical activity during therapy for early breast cancer

Purpose

This study examines congruence between self-reported and device-measured physical activity data in women with early breast cancer and compares trajectories under different treatments.

Methods

Women with non-metastatic breast cancer were recruited before primary therapy. In four weeks distributed over six months after treatment start, patients reported time spent on work, transport, chores and sports via diary and wore Garmin^® vivofit 3 accelerometers to assess steps taken. Associations between these measures and agreement regarding guideline adherence were tested with Spearman’s Correlation Coefficient and Weighted Kappa statistic. Effects of time and treatment were evaluated using mixed analyses of variance.

Results

Ninety-nine participants (median age = 50) were treated with adjuvant (N= 23), neoadjuvant (N= 21) or without chemotherapy (N= 55). Coherence between self-report and device data was strong (r = 0.566). Agreement about reaching recommendations was only “fair” (kappa coefficient = 0.321 and 0.249, resp.). Neither treatment or week nor their interaction had effects on step counts (all p > 0.05). Self-reported activity time was lower for patients with chemotherapy than for those without (adjuvant: ∆ = 69min, p= 0.006, neoadjuvant: ∆ = 45min, p= 0.038) and lower in week 18 than in week 3 (∆ = 43min, p= 0.010).

Conclusion

Results show that consumer-grade activity monitors and self-reports correlate but show different perspectives on physical activity in breast cancer patients. In general, patients perceive some decline regardless of primary treatment regimen. Those affected should be offered assistance to gain the benefits of activity. Accelerometers may help professionals to identify these individuals and patients to verify appraisal of their activity levels.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06195-7.

Randomized controlled trial of a breast cancer Survivor Stories intervention for African American women

RATIONALE

Video-based interventions hold promise for improving quality of life (QoL) among African American breast cancer patients.

OBJECTIVE

An interactive, cancer-communication intervention using African American breast cancer survivors' narratives was tested in a randomized controlled trial to determine whether viewing survivor stories improved newly diagnosed African American breast cancer patients' QoL.

METHOD

Participants were 228 African American women with non-metastatic breast cancer interviewed five times over two years; 120 controls received standard medical care, and 108 intervention-arm participants also received a tablet-computer with survivor stories three times in 12 months. Growth curve models were used to analyze differences between arms in change in eight RAND 36-Item Health Survey subscales, depressive symptoms, and concerns about recurrence. Additional models explored the effects of intervention usage and other intervention-related variables on QoL among patients in the intervention arm.

RESULTS

Models showed no effect of study arm on QoL, depressive symptoms, or concerns about recurrence. Longer use of the intervention was associated with an increase in concerns about recurrence and decline in three QoL subscales: emotional wellbeing, energy/fatigue, and role limitations due to physical health.

CONCLUSION

Although no significant impact of the intervention on QoL was observed when comparing the two study arms, in the intervention arm longer intervention use was associated with declines in three QoL subscales and increased concerns about recurrence. Women with improving QoL may have interacted with the tablet less because they felt less in need of information; it is also possible that encouraging patients to compare themselves to survivors who had already recovered from breast cancer led some patients to report lower QoL. Future work is warranted to examine whether adding different stories to this cancer-communication intervention or using stories in conjunction with additional health promotion strategies (e.g., patient navigation) might improve QoL for African American breast cancer patients.

A Meta-Regression Analysis of Utility Weights for Breast Cancer: The Power of Patients' Experience

To summarize utility estimates of breast cancer and to assess the relative impacts of study characteristics on predicting breast cancer utilities. We searched Medline, Embase, RISS, and KoreaMed from January 1996 to April 2019 to find literature reporting utilities for breast cancer. Thirty-five articles were identified, reporting 224 utilities. A hierarchical linear model was used to conduct a meta-regression that included disease stages, assessment methods, respondent type, age of the respondents, and scale bounds as explanatory variables. The utility for early and late-stage breast cancer, as estimated by using the time-tradeoff with the scales anchored by death to perfect health with non-patients, were 0.742 and 0.525, respectively. The severity of breast cancer, assessment method, and respondent type were significant predictors of utilities, but the age of the respondents and bounds of the scale were not. Patients who experienced the health states valued 0.142 higher than did non-patients (P <0.001). Besides the disease stage, the respondent type had the highest impact on breast cancer utility.

Pre-diagnostic allostatic load and health-related quality of life in a cohort of Black breast cancer survivors

PURPOSE

To determine the association of pre-diagnostic allostatic load (AL) with health-related quality of life (HRQOL) among Black women with breast cancer.

METHODS

In a sample of 409 Black women with non-metastatic breast cancer enrolled in the Women's Circle of Health Follow-Up Study (WCHFS), two pre-diagnostic AL measures were estimated using medical records data from up to 12 months prior to breast cancer diagnosis: AL-lipid/metabolic profile-based measure and AL-inflammatory profile-based measure. HRQOL was assessed approximately 24 months post diagnosis, using the Functional Assessment of Cancer Therapy-Breast Cancer (FACT-B) instrument, including 5 subscale scores [presented by physical well-being (PWB), social & family well-being (SFWB), emotional well-being (EWB), functional well-being (FWB), and breast cancer-specific scale (BCS)] and 3 derived total scores [presented by trial outcome index (TOI), Functional Assessment of Cancer Therapy-General (FACT-G) and FACT-B]. We used multivariable logistic regression models, using dichotomized AL scores (lower AL: 0-3 points, higher AL: 4-8 points), to assess the associations between the two pre-diagnostic AL measures and HRQOL.

RESULTS

Higher pre-diagnostic AL was associated with poorer FWB and lower FACT-G, but these associations were statistically significant for the AL-inflammatory profile-based measure (FWB: OR 1.63, 95% CI 1.04, 2.56; FACT-G: OR 1.62, 95% CI 1.04, 2.54), but not the AL-lipid/metabolic profile-based measure (FWB: OR 1.45, 95% CI 0.81, 2.59; FACT-G: OR 1.33, 95% CI 0.75, 2.37).

CONCLUSION

These findings suggest that higher AL, particularly when measured using the inflammatory profile-based measure, was associated with poorer HRQOL, namely FWB and FACT-G, among Black breast cancer survivors.

Quality of Life Among Breast Cancer Patients Attending Hawassa University Comprehensive Specialized Hospital Cancer Treatment Center

BACKGROUND

Breast cancer affects the overall quality of life (QOL) among its survivors. Limited evidence is available about the QOL among cases. Therefore, this study was intended to assess the quality of life of breast cancer patients attending the cancer treatment center at Hawassa University Comprehensive Specialized Hospital, Hawassa, southern Ethiopia.

METHODS

An institution-based cross-sectional study was conducted among breast cancer patients attending cancer treatment at the Hawassa University Comprehensive Specialized Hospital between April and June, 2019. All breast cancer patients attending treatment the center were included in the study by universal sampling. Data were collected using a structured questionnaire containing demographic data, patient clinical factors and Quality of Life Instrument (WHOQOL)-BREF version 3.0. The collected data were entered into EpiData software version 3.1 and analyzed using SPSS Version 20.0. Descriptive statistics were presented in tables.

RESULTS

A total of 259 respondents with a mean age of (SD) 44.89 (12.56) participated in study. The mean score of overall global health scale was 75.3 (SD±17.1) with the mean health satisfaction was 12.43 (SD±3.98). The highest mean score was observed in environmental domain, 93.31 (SD±19.76), despite social domain being very low, 36.69 (SD±7.62). Most of the participants were highly satisfied with the health care service that was provided, with a mean score of 16.1 (SD±3.1). In contrast, the majority of study participants were disappointed with the need for any medical treatment, body appearance, luxurious activities, and sexual life, with mean scores of 8.93 (SD±3.68), 8.74 (SD±4.26), 9.1 (SD±4.22), and 8.1 (SD±4.14), respectively.

CONCLUSION

Breast cancer patients in southern Ethiopia suffered from poor social and psychological support that, in turn, highly affected their life value. Therefore, due attention should be given to enhance social and psychological support for breast cancer patients as a whole.

Evaluation of Long-Term Satisfaction with Breast Surgery in Patients Treated for Ductal Carcinoma In Situ: A Population-Based Longitudinal Cohort Study

BACKGROUND

Breast-conserving surgery (BCS) and mastectomy have equivalent survival for ductal carcinoma in situ (DCIS), allowing patients to participate in selecting a personalized surgical option; however, this decision-making role can increase patient anxiety. Data evaluating patient satisfaction with their decision to undergo BCS versus mastectomy for the treatment of DCIS are limited.

METHODS

Women with DCIS were enrolled in a population-based, state-wide cohort from 1997 to 2006. Participants were surveyed about their satisfaction with their surgical and reconstruction decisions. Quality-of-life (QoL) evaluations were performed with biennial follow-up surveys though 2016. Multivariable logistic regression modeling examined the relationship between type of surgery and reconstruction with patient satisfaction.

RESULTS

Overall, 1537 women were surveyed, on average, 2.9 years following DCIS diagnosis. Over 90% reported satisfaction with their treatment decision regardless of surgery type. Women who underwent mastectomy with reconstruction were more likely to report lower levels of satisfaction than women who underwent BCS (odds ratio [OR] 2.98, 95% confidence interval [CI] 1.18-7.51, p < 0.01). However, over 80% of women who underwent mastectomies reported satisfaction with their reconstruction decision. Women without reconstruction had the highest levels of satisfaction, while women with implants were more likely to be dissatisfied (implant + autologous: OR 2.77, 95% CI 1.24-6.24; implant alone: OR 4.02, 95% CI 1.947-8.34, p ≤ 0.01). QoL scores were not associated with differences in surgical or reconstruction satisfaction at 5, 10, and 15 years following DCIS diagnosis.

CONCLUSIONS

Women undergoing surgery for DCIS express satisfaction with their treatment decisions. Following mastectomy, most women are satisfied with their reconstruction decision, including women who did not undergo reconstruction.

Expectations of breast-conserving therapy: a qualitative study

Background

Early-stage breast cancer is often treated with breast-conserving therapy (BCT), including lumpectomy with radiation therapy. Patients’ expectations of BCT remain largely unknown. Expectations affect perceptions of treatment-related experiences and health-related quality of life (HR-QOL) outcomes. Our primary aim was to describe expectations of BCT among patients with early breast cancer through qualitative methods. Our secondary aim was to inform preoperative patient education and improve the patient experience through knowledge.

Methods

We used a grounded-theory approach to investigate a convenience sample of 22 women with stage I and II breast cancer who were treated with BCT at a single hospital in New York City between May and August 2016. Semi-structured interviews were conducted in person and by telephone. Open-ended questions covered participants’ expectations of treatment experiences and outcomes. Data was analyzed in a line-by-line approach to identify emergent themes related to patient expectations. Interviews continued until no new themes emerged.

Results

Analysis of data identified the following themes related to patient expectations of BCT: experience of cancer care, recovery, appearance, and HR-QOL. Despite preoperative informed consent and teaching, participants expressed few expectations preoperatively, owing to a lack of knowledge about the process of care. Lack of expectations preoperatively was compensated with available care and resources postoperatively.

Conclusions

Patients in our sample had a surprisingly limited understanding of what to expect during treatment with BCT. Despite available information and preoperative teaching, patients have a clear knowledge gap regarding BCT. These findings suggest patients often undergo cancer treatment with trust rather than complete understanding of the process. This data may be used to enhance preoperative discussions aimed at preparing patients for surgery and treatment.

Comparing Quality of Life in Breast Cancer Patients Who Underwent Mastectomy Versus Breast-Conserving Surgery: A Meta-Analysis

: The purpose of our study was to carry out a meta-analysis of current literature to determine whether total mastectomy and breast-conserving surgery induce different outcomes in quality of life, based on the breast-cancer-specific module of the European Organizaation for Research and Treatment of Cancer core questionnaire (EORTC QLQ-BR23) used postoperatively. A systematic literature search of PubMed and EMBASE was conducted. Observational clinical studies that compared the quality of life in different surgery groups and presented empirical findings were selected. Six studies met the inclusion criteria. Breast-conserving surgery has statistically significant better outcomes than mastectomy in three of the eight outcomes measured in the EORTC QLQ-BR23, namely body image (standard mean difference, SMD = 1.742, 95% CI 0.579-2.905, p = 0.003), future perspective (SMD = 0.606, 95% CI 0.075-1.138, p = 0.025) and systemic therapy side effects (SMD = -0.641, 95% CI 0.101-1.181, p = 0.020). Our study highlighted that breast-conserving surgery was preferred over mastectomy because breast-conserving surgery leads to better outcomes in body image, future perspectives and less systemic side effects.

Optimal designs in three-level cluster randomized trials with a binary outcome

Cluster randomized trials (CRTs) were originally proposed for use when randomization at the subject level is practically infeasible or may lead to a severe estimation bias of the treatment effect. However, recruiting an additional cluster costs more than enrolling an additional subject in an individually randomized trial. Under budget constraints, researchers have proposed the optimal sample sizes in two-level CRTs. CRTs may have a three-level structure, in which two levels of clustering should be considered. In this paper, we propose optimal designs in three-level CRTs with a binary outcome, assuming a nested exchangeable correlation structure in generalized estimating equation models. We provide the variance of estimators of three commonly used measures: risk difference, risk ratio, and odds ratio. For a given sampling budget, we discuss how many clusters and how many subjects per cluster are necessary to minimize the variance of each measure estimator. For known association parameters, the locally optimal design is proposed. When association parameters are unknown but within predetermined ranges, the MaxiMin design is proposed to maximize the minimum of relative efficiency over the possible ranges, that is, to minimize the risk of the worst scenario.

Quality of life, fatigue and changes therein as predictors of return to work during breast cancer treatment

PURPOSE

To our knowledge, only one study has assessed Quality of Life (QOL) as a predictor of return to work (RTW) during breast cancer treatment and one has evaluated multidimensional cancer-related fatigue (CRF) as a determinant of RTW. However, no study has assessed the impact of changes in these variables on RTW. The objective of this study was to evaluate QOL, multidimensional CRF and changes in these variables as determinants of RTW during breast cancer treatment.

METHODS

We performed a longitudinal study of 68 patients with a mean age of 46.97 years (SD = 6.92), who were employed at the time of diagnosis. Women were assessed at the beginning of adjuvant treatments (T0) and followed up with by telephone at three (T1) and 6 months later (T2), using questionnaires (QLQ-C30; MFI-20).

RESULTS

Global QOL, OR = 1.12 [1.01-1.25], sleep disturbance, OR = 1.04 [1.002-1.08], fatigue (QLQ-C30), OR = 0.93 [0.88-0.99], nausea-vomiting, OR = 0.84 [0.73-0.97], reduced motivation, OR = 1.49 [1.05-2.11] and general fatigue, OR = 0.79 [0.63-0.99] at T0 were associated with RTW at T1. At T2 global QOL, OR = 1.09 [1.01-1.17], cognitive functioning, OR = 1.10 [1.03-1.17], general fatigue, OR = 1.82 [1.04-3.17] and mental fatigue, OR = 0.29 [0.11-0.81] were associated with RTW. Furthermore, changes in mental fatigue were associated with RTW at T2, OR = 0.02 [0.001-0.29].

CONCLUSIONS

Quality of life, fatigue and their changes in them, especially cognitive functioning and mental fatigue, can play an important role in predicting the RTW of women with breast cancer. This confirms the importance of multidisciplinary care for cancer and the emergence of a theoretical psychological model of RTW.

Relative efficiency of unequal versus equal cluster sizes in cluster randomized trials using generalized estimating equation models

There is growing interest in conducting cluster randomized trials (CRTs). For simplicity in sample size calculation, the cluster sizes are assumed to be identical across all clusters. However, equal cluster sizes are not guaranteed in practice. Therefore, the relative efficiency (RE) of unequal versus equal cluster sizes has been investigated when testing the treatment effect. One of the most important approaches to analyze a set of correlated data is the generalized estimating equation (GEE) proposed by Liang and Zeger, in which the "working correlation structure" is introduced and the association pattern depends on a vector of association parameters denoted by ρ. In this paper, we utilize GEE models to test the treatment effect in a two-group comparison for continuous, binary, or count data in CRTs. The variances of the estimator of the treatment effect are derived for the different types of outcome. RE is defined as the ratio of variance of the estimator of the treatment effect for equal to unequal cluster sizes. We discuss a commonly used structure in CRTs-exchangeable, and derive the simpler formula of RE with continuous, binary, and count outcomes. Finally, REs are investigated for several scenarios of cluster size distributions through simulation studies. We propose an adjusted sample size due to efficiency loss. Additionally, we also propose an optimal sample size estimation based on the GEE models under a fixed budget for known and unknown association parameter (ρ) in the working correlation structure within the cluster.

The impact of physical activity on fatigue and quality of life during and after adjuvant treatment for breast cancer

BACKGROUND

Although physical activity (PA) can alleviate fatigue and improve quality of life (QoL) in patients with breast cancer (BC), not all domains of PA may have equal impact. The objective of the current study was to examine the longitudinal impact of PA components on the evolution of fatigue and QoL during and after adjuvant treatment for BC.

METHODS

The women included in the study were participants in the 2-year longitudinal FATSEIN ("Fatigue dans le cancer du Sein") study. Fatigue and QoL were measured using the Multidimensional Fatigue Inventory and the European Organization for Research and Treatment of Cancer 30-item QoL questionnaire, respectively. Group-based trajectory analysis was used to determine patterns of PA evolution (frequency, duration, and intensity). Cross-sectional and longitudinal associations between PA patterns and fatigue and QoL were analyzed by using multivariable linear regression and a mixed model.

RESULTS

Among the 424 women who were included (mean ± standard deviation age, 57.1 ± 10.4 years), 2 trajectories were identified for each of the 3 PA components: low and insufficient frequency (51.2%) or regular and moderate frequency (48.8%), low and insufficient duration (47.6%) or regular and moderate duration (52.4%), and low intensity (47.2%) or low to moderate intensity (52.8%). Overall, during treatment, fatigue was increased and QoL was decreased, and the reverse was observed after treatment. During treatment, increased fatigue and decreased QoL were limited by regular PA frequency (β = -8.71 for total fatigue; β = 14.59 for emotional function), but the results were less significant after treatment.

CONCLUSIONS

PA, especially its frequency, is an important determinant of fatigue and QoL during adjuvant treatment for BC. The promotion of regular PA among women who are receiving treatment for BC may be an effective way to reduce fatigue and improve QoL. Cancer 2018;124:797-806. © 2017 American Cancer Society.

Accelerated partial breast irradiation compared with whole breast radiation therapy: a breast cancer cohort study measuring change in radiation side-effects severity and quality of life

PURPOSE

Radiotherapy (RT) after breast-conserving surgery for early-stage breast cancer patients has similar survival benefits with whole breast RT (WBRT) or accelerated partial breast irradiation (APBI). However, the impact of RT type and side-effects severity on change in quality of life (QOL) is unknown. We examined changes in RT side-effects severity and QOL by RT type.

METHODS

We analyzed data from a cohort of 285 newly diagnosed early-stage breast cancer patients with tumor size ≤3.0 cm and lymph node-negative disease. Patients (93 [32.6%] stage 0; 49 [17.2%] non-white; mean age = 59.3 years) completed four interviews (6 weeks, 6, 12, and 24 months) after definitive surgical treatment. We measured severity of RT side effects, fatigue and skin irritation, using a 5-point scale (1 "not at all" to 5 "all the time") and measured QOL using the Functional Assessment of Cancer Therapy-Breast (FACT-B) and RAND 36-item Health Survey Vitality subscale. Repeated-measures analysis of covariance of each outcome controlled for demographic, clinical/treatment, and psychosocial factors.

RESULTS

Patients initiated RT by 6 months (113 received APBI; 172 received WBRT) and completed RT by 12 months. Patients receiving WBRT (vs. APBI) reported greater increase in fatigue and skin irritation severity from 6-week to 6-month interviews (each P < 0.001). Improvement in neither total FACT-B nor Vitality differed significantly by RT type over 2-year follow-up.

CONCLUSIONS

Findings suggest that early-stage breast cancer patients can benefit from less-severe, short-term side effects of APBI with no differential impact on QOL change within 2-year follow-up.

Optimal design of longitudinal data analysis using generalized estimating equation models

Longitudinal studies are often applied in biomedical research and clinical trials to evaluate the treatment effect. The association pattern within the subject must be considered in both sample size calculation and the analysis. One of the most important approaches to analyze such a study is the generalized estimating equation (GEE) proposed by Liang and Zeger, in which "working correlation structure" is introduced and the association pattern within the subject depends on a vector of association parameters denoted by ρ. The explicit sample size formulas for two-group comparison in linear and logistic regression models are obtained based on the GEE method by Liu and Liang. For cluster randomized trials (CRTs), researchers proposed the optimal sample sizes at both the cluster and individual level as a function of sampling costs and the intracluster correlation coefficient (ICC). In these approaches, the optimal sample sizes depend strongly on the ICC. However, the ICC is usually unknown for CRTs and multicenter trials. To overcome this shortcoming, Van Breukelen et al. consider a range of possible ICC values identified from literature reviews and present Maximin designs (MMDs) based on relative efficiency (RE) and efficiency under budget and cost constraints. In this paper, the optimal sample size and number of repeated measurements using GEE models with an exchangeable working correlation matrix is proposed under the considerations of fixed budget, where "optimal" refers to maximum power for a given sampling budget. The equations of sample size and number of repeated measurements for a known parameter value ρ are derived and a straightforward algorithm for unknown ρ is developed. Applications in practice are discussed. We also discuss the existence of the optimal design when an AR(1) working correlation matrix is assumed. Our proposed method can be extended under the scenarios when the true and working correlation matrix are different.

Effectiveness of a multimodal standard nursing program on health-related quality of life in Chinese mainland female patients with breast cancer: protocol for a single-blind cluster randomized controlled trial

Background

Breast cancer and its treatment-related adverse effects are harmful to physical, psychological, and social functioning, leading to health-related quality of life (HRQoL) impairment in patients. Many programs have been used with this population for HRQoL improvement; however, few studies have considered the physical, psychological, and social health domains comprehensively, and few have constructed multimodal standard nursing interventions based on specific theories. The purpose of this trial is to examine the effect of a health belief model (HBM)-based multimodal standard nursing program (MSNP) on HRQoL in female patients with breast cancer.

Methods

This is a two-arm single-blind cluster randomized controlled trial (cRCT) in clinical settings. Twelve tertiary hospitals will be randomly selected from the 24 tertiary hospitals in Xi’an, China, and allocated to the intervention arm and control arm using a computer-generated random numbers table. Inpatient female patients with breast cancer from each hospital will receive either MSNP plus routine nursing care immediately after recruitment (intervention arm), or only routine nursing care (control arm). The intervention will be conducted by trained nurses for 12 months. All recruited female patients with breast cancer, participating clinical staff, and trained data collectors from the 12 hospitals will be blind with respect to group allocation. Patients of the control arm will not be offered any information about the MSNP during the study period to prevent bias. The primary outcome is HRQoL measured through the Functional Assessment of Cancer Therapy-Breast version 4.0 at 12 months. Secondary outcomes include pain, fatigue, sleep, breast cancer-related lymphedema, and upper limb function, which are evaluated by a visual analogue scale, the circumference method, and the Constant-Murley Score.

Discussion

This trial will provide important evidence on the effectiveness of multimodal nursing interventions delivered by nurses in clinical settings. Study findings will inform strategies for scaling up comprehensive standard intervention programs on health management in the population of female patients with breast cancer.

Trial registration

Chictr.org.cn ChiCTR-IOR-16008253 (April 9, 2016)