Obesity or overweight is associated with worse pathological response to neoadjuvant chemotherapy among Chinese women with breast cancer

Obesity Is an Independent Prognostic Factor That Reduced Pathological Complete Response in Operable Breast Cancer Patients

Background and Objectives: Obesity is a significant risk factor for the development of breast cancer (BC) and associated poorer outcomes. A pathological complete response (pCR) with neoadjuvant chemotherapy (NACT) correlates with improved long-term prognosis in BC patients. In this study, we aimed to investigate the predictive effect of obesity on achieving pCR following NACT. Methods: This single-center retrospective study included patients with operable BC who were treated with NACT. Patients were categorized based on their pre-chemotherapy body mass index (BMI), including non-obese (<30 kg/m2) and obese (≥30 kg/m2) groups, and pathological responses to NACT were compared. Results: A total of 191 female patients were included in this study; of these, 83 (43.4%) were obese and 108 (56.6%) were in the non-obese group. Obesity was more common in postmenopausal patients, and the median age of obese patients was significantly higher compared to non-obese patients. Patients in the obese group demonstrated significantly lower pCR rates compared to the non-obese group (30% vs. 45%, p = 0.03). The histological subtype assessment indicated that only in the HR-positive/HER2-negative patients was the pCR rate significantly lower in the obese group compared to the non-obese group (11% vs. 27%, p = 0.05). According to menopausal assessment, a significant difference in pCR rates was observed only among postmenopausal patients, with rates of 29% in the obese group compared to 52% in the non-obese group (p = 0.03). In logistic regression analysis, obesity (OR: 0.52, 95% CI: 0.28-0.97; p = 0.04) and a low Ki-67 score (HR: 2.7, 95% CI: 1.37-5.53; p = 0.003) were independently associated with a decreased rate of pCR. Conclusions: The impact of obesity on achieving pCR in BC patients undergoing NACT remains controversial. Our study revealed that obesity was an independently significant negative predictive factor for achieving pCR.

Effect of a multimodal intervention in breast Cancer patients undergoing neoadjuvant therapy: A study protocol of the multimodal project

BACKGROUND AND AIMS

To determine the effect of a multimodal intervention (nutritional behavior change and physical exercise) on quality of life, chemotherapy response rate and tolerance, histopathological level of the tumor, body composition, and biochemical parameters, in patients diagnosed with breast cancer during neoadjuvant chemotherapy treatment, and to compare them with the control group.

METHODS

Anticipated 80 patients diagnosed with breast cancer aged 18-70 years will be recruited for this randomized, unblinded clinical trial based on a nutritional behavior change and physical exercise in patients during the approximately 6 months in which the patient receives neoadjuvant treatment. Participants will be randomly allocated (1:1) to one of two groups (intervention or control). Primary and secondary outcomes will be assessed before the beginning and after the neoadjuvant treatment (before surgery). The primary outcome is quality of life, whereas secondary outcomes include chemotherapy response rate and tolerance, histopathological level of the tumor and body composition (i.e., visceral adipose tissue activity, bone, lean and fat masses). We will analyze blood parameters (i.e., biochemical, inflammatory, and tumor markers) as exploratory outcomes.

CONCLUSION

This study will address the influence of a practical and viable multimodal intervention (i.e., nutritional behavior change and physical exercise) on breast cancer patients undergoing neoadjuvant chemotherapy. Given the practical viability of the intervention in real-world settings, our study holds promise for significant scientific and clinical implications.

Macronutrient-differential dietary pattern impacts on body weight, hepatic inflammation, and metabolism

Introduction

Obesity is a multi-factorial disease frequently associated with poor nutritional habits and linked to many detrimental health outcomes. Individuals with obesity are more likely to have increased levels of persistent inflammatory and metabolic dysregulation. The goal of this study was to compare four dietary patterns differentiated by macronutrient content in a postmenopausal model. Dietary patterns were high carbohydrate (HC), high fat (HF), high carbohydrate plus high fat (HCHF), and high protein (HP) with higher fiber.

Methods

Changes in body weight and glucose levels were measured in female, ovariectomized C57BL/6 mice after 15 weeks of feeding. One group of five mice fed the HCHF diet was crossed over to the HP diet on day 84, modeling a 21-day intervention. In a follow-up study comparing the HCHF versus HP dietary patterns, systemic changes in inflammation, using an 80-cytokine array and metabolism, by untargeted liquid chromatography-mass spectrometry (LCMS)-based metabolomics were evaluated.

Results

Only the HF and HCHF diets resulted in obesity, shown by significant differences in body weights compared to the HP diet. Body weight gains during the two-diet follow-up study were consistent with the four-diet study. On Day 105 of the 4-diet study, glucose levels were significantly lower for mice fed the HP diet than for those fed the HC and HF diets. Mice switched from the HCHF to the HP diet lost an average of 3.7 grams by the end of the 21-day intervention, but this corresponded with decreased food consumption. The HCHF pattern resulted in dramatic inflammatory dysregulation, as all 80 cytokines were elevated significantly in the livers of these mice after 15 weeks of HCHF diet exposure. Comparatively, only 32 markers changed significantly on the HP diet (24 up, 8 down). Metabolic perturbations in several endogenous biological pathways were also observed based on macronutrient differences and revealed dysfunction in several nutritionally relevant biosynthetic pathways.

Conclusion

Overall, the HCHF diet promoted detrimental impacts and changes linked to several diseases, including arthritis or breast neoplasms. Identification of dietary pattern-specific impacts in this model provides a means to monitor the effects of disease risk and test interventions to prevent poor health outcomes through nutritional modification.

Impact of body mass index on pathological response after neoadjuvant chemotherapy: results from the I-SPY 2 trial

PURPOSE

Increased body mass index (BMI) has been associated with poor outcomes in women with breast cancer. We evaluated the association between BMI and pathological complete response (pCR) in the I-SPY 2 trial.

METHODS

978 patients enrolled in the I-SPY 2 trial 3/2010-11/2016 and had a recorded baseline BMI prior to treatment were included in the analysis. Tumor subtypes were defined by hormone receptor and HER2 status. Pretreatment BMI was categorized as obese (BMI ≥ 30 kg/m2), overweight (25 ≤ BMI < 30 kg/m2), and normal/underweight (< 25 kg/m2). pCR was defined as elimination of detectable invasive cancer in the breast and lymph nodes (ypT0/Tis and ypN0) at the time of surgery. Logistic regression analysis was used to determine associations between BMI and pCR. Event-free survival (EFS) and overall survival (OS) between different BMI categories were examined using Cox proportional hazards regression.

RESULTS

The median age in the study population was 49 years. pCR rates were 32.8% in normal/underweight, 31.4% in overweight, and 32.5% in obese patients. In univariable analysis, there was no significant difference in pCR with BMI. In multivariable analysis adjusted for race/ethnicity, age, menopausal status, breast cancer subtype, and clinical stage, there was no significant difference in pCR after neoadjuvant chemotherapy for obese compared with normal/underweight patients (OR = 1.1, 95% CI 0.68-1.63, P = 0.83), and for overweight compared with normal/underweight (OR = 1, 95% CI 0.64-1.47, P = 0.88). We tested for potential interaction between BMI and breast cancer subtype; however, the interaction was not significant in the multivariable model (P = 0.09). Multivariate Cox regression showed there was no difference in EFS (P = 0.81) or OS (P = 0.52) between obese, overweight, and normal/underweight breast cancer patients with a median follow-up time of 3.8 years.

CONCLUSION

We found no difference in pCR rates by BMI with actual body weight-based neoadjuvant chemotherapy in this biologically high-risk breast cancer population in the I-SPY2 trial.

Impact of Body Mass Index on Pathological Response after Neoadjuvant Chemotherapy: Results from the I-SPY 2 trial

Purpose

Increased body mass index (BMI) has been associated with poor outcomes in women with breast cancer. We evaluated the association between BMI and pathological complete response (pCR) in the I-SPY 2 trial.

Methods

978 patientsenrolled in the I-SPY 2 trial 3/2010-11/2016 and had a recorded baseline BMI prior to treatment were included in the analysis. Tumor subtypes were defined by hormone receptor and HER2 status. Pretreatment BMI was categorized as obese (BMI≥30 kg/m2), overweight (25≤BMI < 30 kg/m2), and normal/underweight (< 25 kg/m2). pCR was defined as elimination of detectable invasive cancer in the breast and lymph nodes (ypT0/Tis and ypN0) at the time of surgery. Logistic regression analysis was used to determine associations between BMI and pCR. Event-free survival (EFS) and overall survival (OS) between different BMI categories were examined using Cox proportional hazards regression.

Results

The median age in the study population was 49 years. pCR rates were 32.8% in normal/underweight, 31.4% in overweight, and 32.5% in obese patients. In univariable analysis, there was no significant difference in pCR with BMI. In multivariable analysis adjusted for race/ethnicity, age, menopausal status, breast cancer subtype, and clinical stage, there was no significant difference in pCR after neoadjuvant chemotherapy for obese compared with normal/underweight patients (OR = 1.1, 95% CI: 0.68-1.63, p = 0.83), and for overweight compared with normal/underweight (OR = 1, 95% CI: 0.64-1.47, p = 0.88). We tested for potential interaction between BMI and breast cancer subtype; however, the interaction was not significant in the multivariable model (p = 0.09). Multivariate Cox regression showed there was no difference in EFS (p = 0.81) or OS (p = 0.52) between obese, overweight, and normal/underweight breast cancer patients with a median follow-up time of 3.8 years.

Conclusions

We found no difference in pCR rates by BMI with actual body weight based neoadjuvant chemotherapy in this biologically high-risk breast cancer population in the I-SPY2 trial.

Impact of body mass index in therapeutic response for HER2 positive breast cancer treated with neoadjuvant targeted therapy: a multi-center study and meta-analysis

While overweight/obesity has become a major public health issue worldwide, any association between body mass index (BMI) and therapeutic response in neoadjuvant targeted therapy treated HER2 positive breast cancer patients remain unclear. The information from a total of four-hundred and ninety-one neoadjuvant targeted therapy treated HER2 positive breast cancer patients from four institutions were retrospectively collected. Univariate and multivariate logistic analysis was developed to determine the association between BMI and therapeutic response. A meta-analysis of published literature was then conducted to confirm the effect of overweight/obesity on pCR for patients treated with neoadjuvant targeted therapy. Restricted cubic spline (RCS) adjusted for confounding factors demonstrated a decrease pCR with increasing BMI (OR = 0.937, P = 0.045). Patients were then categorized into under/normal weight (n = 299) and overweight/obesity (n = 192). Overweight/obese patients were independently associated with a poor therapeutic response. In the subgroup analysis, a significant negative impact of overweight/obesity on pCR can be observed both in single-targeted (OR = 0.556; P = 0.02) and dual-targeted (OR = 0.392; P = 0.021) populations. Six eligible studies involving 984 neoadjuvant targeted therapy treated HER2 positive breast cancer patients were included in the meta-analysis. The meta-analysis also demonstrated that overweight/obesity was significantly associated with a poor response to neoadjuvant anti-HER2 therapy (OR = 0.68; P = 0.007). Our result show that overweight and obese HER2 positive breast cancer patients are less likely to achieve pCR after neoadjuvant targeted therapy.

The Predictive Importance of Body Mass Index on Response to Neoadjuvant Chemotherapy in Patients with Breast Cancer

Purpose

The aim of the study was to investigate the effects of body mass index (BMI) on the response to neoadjuvant chemotherapy (NACT) in Turkish patients with local and locally advanced breast cancer.

Methods

The pathological responses for the breast and axilla were assessed according to the Miller-Payne grading (MPG) system. Tumors were grouped into molecular phenotypes and classified as response rates according to the MPG system after the completion of NACT. A 90% or greater reduction in tumor cellularity was considered a good response to treatment. Additionally, patients were grouped according to BMI into <25 (group A) and ≥25 (group B).

Results

In total, 647 Turkish women with breast cancer were included in the study. In the univariate analysis, age, menopause status, tumor diameter, stage, histological grade, Ki-67, estrogen receptor (ER) status, progesterone receptor (PR) status, human epidermal growth factor receptor 2 (HER2) status, and BMI were assessed to determine which of these factors were associated with a ≥90% response rate. Stage, HER2 positivity, triple-negative breast cancer (TNBC; ER-negative, PR-negative, and HER2-negative breast cancer), grade, Ki-67 levels, and BMI were found to be the statistically significant factors for a ≥90% response rate. In the multivariate analysis, grade III disease, HER2 positivity, and TNBC were found to be the factors associated with a high pathological response. Meanwhile, hormone receptor (HR) positivity and a higher BMI were associated with a decreased pathological response in patients receiving NACT for breast cancer.

Conclusion

Our results show that a high BMI and HR positivity are associated with a poor response to NACT in Turkish patients with breast cancer. The findings presented in this study may guide novel studies to examine the NACT response in obese patients with and without insulin resistance.

Atorvastatin improves cisplatin sensitivity through modulation of cholesteryl ester homeostasis in breast cancer cells

BACKGROUND

Acquired treatment resistance is a significant problem in breast cancer management, and alterations in lipid metabolism have been proposed to contribute to the development of drug resistance as well as other aspects of tumor progression. The present study aimed to identify the role of cholesterol metabolism in MCF-7 and MDA-MB-231 breast cancer cell response to cisplatin (CDDP) treatment in the acute setting and in a model of CDDP resistance.

METHODS

MCF-7 (luminal A), MDA-MB-231 (triple-negative) and CDDP-resistant MDA-MB-231 (MDACR) cell lines were grown in the presence or absence of CDDP in combination with atorvastatin (ATV), lipid depletion or low-density lipoprotein loading and were analyzed by a variety of biochemical and radiometric techniques.

RESULTS

Co-administration of CDDP and ATV strongly reduced cell proliferation and viability to a greater extent than CDDP alone, especially in MDA-MB-231 cells. These findings were associated with reduced cholesteryl ester synthesis and storage in MDA-MB-231 cells. In MDACR cells, acetyl-CoA acetyltransferase 1 (ACAT-1) was upregulated compared to naïve MDA-MB-231 cells and ATV treatment restored CDDP sensitivity, suggesting that aberrant ACAT-1 expression and associated changes in cholesterol metabolism contribute to CDDP resistance in MDA-MB-231 cells.

CONCLUSION

These findings indicate that the elevated susceptibility of MDA-MB-231 cells to co-administration of CDDP and ATV, is associated with an increased reliance on cholesteryl ester availability. Our data from these cell culture-based studies identifies altered cholesterol homeostasis as an adaptive response to CDDP treatment that contributes to aggressiveness and chemotherapy resistance.

The association between body mass index and pathological complete response in neoadjuvant-treated breast cancer patients

BACKGROUND

Obesity seems to be associated with a poorer response to adjuvant chemotherapy in breast cancer (BC); however, associations in the neoadjuvant chemotherapy (NACT) setting and according to menopausal status are less studied. This study aims to investigate the association between pretreatment body mass index (BMI) and pathological complete response (pCR) following NACT in BC according to menopausal and estrogen receptor (ER) status.

MATERIAL AND METHODS

The study cohort consisted of 491 patients receiving NACT in 2005-2019. Based on pre-NACT patient and tumor characteristics, the association between BMI and achieving pCR was analyzed using logistic regression models (crude and adjusted models (age, tumor size, and node status)) with stratification by menopausal and ER status.

RESULTS

In the overall cohort, being overweight (BMI ≥25) compared by being normal-weight (BMI <25), increased the odds of accomplishing pCR by 15%. However, based on the 95% confidence interval (CI) the data were compatible with associations within the range of a decrease of 30% to an increase of 89%. Stratification according to menopausal status also showed no strong association: the odds ratio (OR) of accomplishing pCR in overweight premenopausal patients compared with normal-weight premenopausal patients was 1.76 (95% CI 0.88-3.55), whereas for postmenopausal patients the corresponding OR was 0.71 (95% CI 0.35-1.46).

DISCUSSION

In a NACT BC cohort of 491 patients, we found no evidence of high BMI as a predictive factor of accomplishing pCR, neither in the whole cohort nor stratified by menopausal status. Given the limited precision in our results, larger studies are needed before considering BMI in clinical decision-making regarding NACT or not.

Impact of body mass index on pathological complete response and survival of breast cancer patients receiving neoadjuvant chemotherapy

BACKGROUND

High body mass index (BMI) is regarded as a poor prognostic factor in breast cancer (BC). However, its association with pathological complete response (pCR) and survival after neoadjuvant chemotherapy (NAC) remains controversial.

OBJECTIVE

We wanted to assess the prognostic impact of BMI in this setting.

METHODS

Single-center, retrospective review of 314 BC patients undergoing NAC from 2010 to 2018. Patients were categorized as underweight/normal weight (UW/NW) (BMI < 25) or overweight/obese (OW/OB) (BMI ≥ 25). The relationship between BMI and other traditional clinical-pathological prognostic variables with the pCR rate was investigated using logistic regression analysis. The effect on event-free survival (EFS) and overall survival (OS) was estimated by the Cox proportional hazards regression analysis.

RESULTS

One hundred and twenty-two patients were UW/NW while 192 were OW/OB. Multivariate analysis revealed that hormonal receptors negative, HER2 positive, and clinical tumor stage (cT) 1-2 were independent predictor factors for pCR. Multivariate analysis confirmed tumor grade G3 and lack of pCR as independent adverse prognostic factors for EFS, while factors associated with worse OS were cT3-4, hormone receptors negative, and lack of pCR. Non-significant differences in pCR, EFS, or OS were observed between the two baseline BMI categories.

CONCLUSIONS

In our experience, BMI is not associated with pCR, EFS, or OS in BC patients receiving NAC. Achieving pCR is the most consistent factor associated with EFS and OS. Prospective and well-designed studies taking into account other important biological and anthropometric factors are needed to determine the exact role of BMI in this setting.

Clinical verification of body mass index and tumor immune response in patients with breast cancer receiving preoperative chemotherapy

Purpose

The body mass index (BMI) is commonly used as a simple indicator of obesity; patients with early-stage breast cancer who are obese (OB) per BMI measurements have been shown to have high postoperative recurrence and low survival rates. On the other hand, it has been shown that lymphocytes present in the vicinity of malignant growths that are involved in the tumors’ immune responses influence the efficacy chemotherapy. Therefore, we hypothesized that OB patients with breast cancer have a lower density of tumor-infiltrating lymphocytes (TILs), which may influence the therapeutic effect of preoperative chemotherapy (POC). In this study, we measured pretreatment BMI and TILs in patients with breast cancer who underwent POC, examined the correlations between these two factors, and retrospectively analyzed their therapeutic outcomes and prognoses.

Methods

The participants in this study were 421 patients with breast cancer who underwent surgical treatment after POC between February 2007 and January 2019. The patient’s height and weight were measured before POC to calculate the BMI (weight [kg] divided by the square of the height [m²]). According to the World Health Organization categorization, patients who weighed under 18.5 kg/m² were classified as underweight (UW), those ≥18.5 kg/m² and > 25 kg/m² were considered normal weight (NW), those ≥25 kg/m² and < 30 kg/m² were overweight (OW), and those ≥30 kg/m² were OB. The TILs were those lymphocytes that infiltrated the tumor stroma according to the definition of the International TILs Working Group 2014.

Results

The median BMI was 21.9 kg/m² (range, 14.3–38.5 kg/m²); most patients (244; 64.5%) were NW. Among all 378 patients with breast cancer, the TIL density was significantly lower in OB than in NW and OW patients (vs. NW: p = 0.001; vs. OW: p = 0.003). Furthermore, when examining patients with each breast cancer type individually, the OS of those with TNBC who had low BMIs was significantly poorer than that of their high-BMI counterparts (log rank p = 0.031).

Conclusions

Our data did not support the hypothesis that obesity affects the tumor immune microenvironment; however, we showed that being UW does affect the tumor immune microenvironment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08857-7.

Mechanistic Targets and Nutritionally Relevant Intervention Strategies to Break Obesity-Breast Cancer Links

The worldwide prevalence of overweight and obesity has tripled since 1975. In the United States, the percentage of adults who are obese exceeds 42.5%. Individuals with obesity often display multiple metabolic perturbations, such as insulin resistance and persistent inflammation, which can suppress the immune system. These alterations in homeostatic mechanisms underlie the clinical parameters of metabolic syndrome, an established risk factor for many cancers, including breast cancer. Within the growth-promoting, proinflammatory milieu of the obese state, crosstalk between adipocytes, immune cells and breast epithelial cells occurs via obesity-associated hormones, angiogenic factors, cytokines, and other mediators that can enhance breast cancer risk and/or progression. This review synthesizes evidence on the biological mechanisms underlying obesity-breast cancer links, with emphasis on emerging mechanism-based interventions in the context of nutrition, using modifiable elements of diet alone or paired with physical activity, to reduce the burden of obesity on breast cancer.

Influence of serum inflammatory cytokines on cytochrome P450 drug metabolising activity during breast cancer chemotherapy: a patient feasibility study

Individual response to chemotherapy in patients with breast cancer is variable. Obesity and exercise are associated with better and worse outcomes, respectively, and it is known that both impact the systemic cytokine milieu. Cytochrome P450 (CYP) enzymes are responsible for the metabolism of many chemotherapy agents, and CYP enzyme activity has been shown to be modified by inflammatory cytokines in vitro and in vivo. Cytokine-associated changes in CYP metabolism may alter chemotherapy exposure, potentially affecting treatment response and patient survival. Therefore, better understanding of these biological relationships is required. This exploratory single arm open label trial investigated changes in in vivo CYP activity in twelve women treated for stage II or III breast cancer, and demonstrated for the first time the feasibility and safety of utilising the Inje phenotyping cocktail to measure CYP activity in cancer patients receiving chemotherapy. Relative CYP activity varied between participants, particularly for CYP2C9 and CYP2D6, and changes in serum concentrations of the inflammatory cytokine monocyte chemoattractant protein 1 inversely correlated to CYP3A4 activity during chemotherapy. Future use of phenotyping cocktails in a clinical oncology setting may help guide drug dosing and improve chemotherapy outcomes.

Clinical Trial Registration: Trial was retrospectively registered to the Australia New Zealand Clinical Trial Registry (ANZCTR). ACTRN12620000832976, 21 Aug 2020, https://www.anzctr.org.au/ACTRN12620000832976.aspx.

Impact of body mass index on pathological complete response following neoadjuvant chemotherapy in operable breast cancer: a meta-analysis

PURPOSE

The impact of an increased body mass index (BMI) on outcomes of neoadjuvant chemotherapy (NACT) in breast cancer remains controversial. The purpose of this study was to analyze the impact of BMI on pathological complete response (pCR) rates for operable breast cancer after NACT.

METHODS

We searched Medline, Embase, and Web of Science database for observational studies and randomized controlled trials that reported the association of BMI with pCR after NACT. We performed a meta-analysis to assess the impact of BMI on pCR rate.

RESULTS

We identified 13 studies including a total of 18,702 women with operable breast cancer who underwent NACT. Two studies were pooled analyses of prospective clinical trials (10,669 patients); the rest were case-control studies (8033 patients). All studies provided data of two BMI groups (BMI < 25 vs. BMI ≥ 25). Pooled analyses demonstrated that overweight/obese women were less likely to achieve pCR after NACT as compared to under-/normal weight women (odds ratio (OR) = 0.80; 95% confidence interval (CI): 0.68-0.93). Eleven studies provided data of three BMI groups (BMI < 25, 25 ≤ BMI < 30, BMI ≥ 30). Based on pooled analyses, both overweight and obese groups were less likely to achieve pCR with NACT as compared to under-/normal weight group, (OR = 0.77, 95% CI 0.65-0.93 and OR = 0.68, 95% CI 0.61-0.77, respectively).

CONCLUSIONS

Overweight and obese breast cancer patients had a lower pCR rate with NACT compared to patients with under-/normal weight. Further prospective studies may help confirm this finding and investigate possible mechanisms.

Comparison between body composition parameters and response to neoadjuvant chemotherapy by using pre-treatment PET CT in locally advanced breast cancer

•

Weight and the BMI are inadequate proxies for adiposity that do not distinguish between muscle and adipose tissue or different specific deposits of adipose tissue (visceral and subcutaneous), which have different physiological effects.

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Patients with the same BMI are likely to have different anatomical distribution of adipose and muscle tissue.

•

To our knowledge, only few studies have investigated the association between fat and muscle tissue distribution of the body, and response to neoadjuvant chemotherapy.

Purpose

To compare the adipose and muscle tissue areas in patients who responded differently to neoadjuvant chemotherapy.

Methods

One hundred and eighty six patients diagnosed with breast cancer who underwent neoadjuvant chemotherapy between January 2015- October 2019 and were operated after the treatment were retrospectively included in the study. Pathological results were divided into five groups using the Miller-Payne grading systems. Grade 1 indicating no significant reduction in malignant cells; Grade 2: a minor loss of malignant cells (≤ 30 %); Grade 3: reduction in malignant cells between 30 % and 90 %; Grade 4: disappearance of malignant cells >90 %; Grade 5: no malignant cells identifiable. Pre-treatment PET CT scans were evaluated, and calculation of body composition parameters were performed on a single axial section passing through the L3 vertebrae. Spearman’s correlation test was used to analyze the correlation between SAT, VAT, MT parameters and pathological responses.

Results

There was no strong correlation between the 5 groups separated according to neoadjuvant chemotherapy treatment response and tissue distributions. However, that there was a very low correlation found between superficial adipose tissue and pathological response (r=, 156).

Conclusion

In conclusion, our results have provided a very low correlation between SAT and more than 30 % response. More research is required to evaluate the role of the body fat and muscle parameters in response to neoadjuvant chemotherapy in larger patient populations.

Effect of body mass index on response to neo-adjuvant therapy in HER2-positive breast cancer: an exploratory analysis of the NeoALTTO trial

Background

Obesity is a risk factor for breast cancer (BC) development, recurrence, and death. In view of this, we aimed to investigate the clinical value of obesity in BC patients treated with anti-HER2 therapies in the NeoALTTO trial, which randomized 455 patients to neo-adjuvant lapatinib, trastuzumab, or their combination plus paclitaxel.

Methods

Patients were classified according to their basal body mass index (BMI) into underweight (< 18.5 kg/m²), normal (≥ 18.5; < 25 kg/m²), overweight (≥ 25; < 30 kg/m²), and obese (≥ 30 kg/m²) WHO categories. Univariate and multivariate logistic regression analyses were performed using BMI as a categorical variable. Pathological complete response (pCR) and event-free survival (EFS) were the NeoALTTO primary and secondary outcomes, respectively.

Results

Among 454 patients analyzed, 14 (3%), 220 (48%), 137 (30%), and 83 (18%) were classified as underweight, normal weight, overweight, and obese, respectively; 231 (51%) and 223 (49%) had hormone receptor (HR)-positive and HR-negative primary tumors; 160 (35%) achieved pCR. In the overall patient population, no association was found between BMI groups and pCR, as we reported pCR rates of 57.1%, 35%, 30.7%, and 39.8% in underweight, normal weight, overweight, and obese cases, respectively. In contrast, in HR-positive tumors, overweight or obesity was generally associated with decreased likelihood of achieving a pCR independently of other clinical variables, including planned surgery, nodal status, and tumor size (odds ratio [OR] = 0.55, 95%CI 0.30–1.01, as compared to normal or underweight; p = 0.053); notably, no differential effect of BMI with respect to pCR was observed in HR-negative cases (odds ratio [OR] = 1.30, 95%CI 0.76–2.23, as compared to normal or underweight; p = 0.331), resulting in a statistically significant interaction between BMI and HR status (p = 0.036). There was no association between BMI and EFS neither in the overall nor in the HR-positive population, but this analysis was under-powered.

Conclusions

NeoALTTO patients overweight or obese at baseline and with HR-positive primary BC appeared less likely to achieve pCR after neo-adjuvant anti-HER2 therapies. This finding paves the way to future research in targeting the interplay between HER2/HR signaling and metabolism.

Inhibition of the PI3K-AKT-mTOR pathway suppresses the adipocyte-mediated proliferation and migration of breast cancer cells

Objective: Although it is well known that adipocyte significantly affects breast cancer progression, its mechanism has not been fully understood. Here, we analyzed the effect of adipocytes on breast cancer progression including cell proliferation and migration. Materials and Methods: We treated the conditioned media obtained from mouse 3T3-L1-derived or human adipose tissue-derived mesenchymal stem cells (hAMSC)-derived adipocytes to breast cancer cells, MCF-7 and MDA-MB-231. And then, cells viability and proliferation were analyzed using MTT assays and colony forming assays, respectively. Also mRNA expression of inflammatory cytokines and proteins expression in main signal pathway were analyzed by RT-qPCR and immunoblotting, respectively. Results: Adipocyte-derived conditioned media increased the proliferation and migration of MCF-7 and MDA-MB-231 cells while little effects in a human normal immortalized mammary epithelial cell line MCF10A. In addition, adipocyte-derived conditioned media induced phosphorylation of AKT and mTOR and upregulated the expression of target genes of the PI3K-AKT-mTOR pathway including IL6, IL1β, IL1α and TNFα in breast cancer cells. Furthermore, BEZ235 a dual inhibitor of PI3K and mTOR significantly decreased the adipocyte-mediated the proliferation and migration of breast cancer cells. Conclusion: Adipocyte-derived conditioned media enhance the proliferation and migration of breast cancer cells through the PI3K-AKT-mTOR pathway, supporting the importance of heterotypic interactions between breast cancer cells and adipocytes in the tumor microenvironment.

Weight Gain during Neoadjuvant Chemotherapy is Associated with Worse Outcome among the Patients with Operable Breast Cancer

Purpose

This study was aimed at identifying the influence of initial weight and weight change during neoadjuvant chemotherapy (NAC) on pathologic complete response (pCR) and long-term survival in Chinese patients with operable breast cancer.

Methods

We conducted a retrospective study using data from 409 female patients who received NAC for stage II or III breast cancer and had complete record of body mass index (BMI) before and after NAC. BMI of < 25 kg/m² was categorized as normal weight/underweight (NW/UW); 25.0–29.9 kg/m² was categorized as overweight (OW); ≥30 kg/m² was categorized as obese (OB). BMI change was defined as the difference in BMI between day 1 of the first cycle of NAC and the day before surgery. A BMI gain or loss of > 2 kg/m² following NAC was considered to be significant, else was considered stable. The study end points included pCR rates, disease-free survival (DFS), and overall survival (OS).

Results

The median follow-up time was 43.2 (8.9–93.6) months. The average BMI was 23.40 ± 3.04 kg/m² before NAC and 23.66 ± 3.02 kg/m² after NAC (t = −3.604, p < 0.001). The pCR rate was 25.3% in the NW/UW group and 24.1% in the OW/OB group (p = 0.811), and was similar between the BMI-gain (23.3%) and the BMI-stable/loss (25.1%) groups (p = 0.787). Initial BMI was an independent prognostic factor for DFS (hazard ratio, 1.69; 95% confidence interval [CI], 1.13–2.53; p = 0.011) but not for OS, while BMI-gain was an independent prognostic factor for both DFS (hazard ratio, 2.09; 95% CI, 1.28–3.42; p = 0.003) and OS (hazard ratio, 1.97; 95% CI, 1.04–3.74; p = 0.039).

Conclusion

BMI increased after NAC in Chinese breast cancer patients. Initial BMI and BMI change during NAC were not associated with pCR but were reversely associated with survival.

Leptin Signaling Mediates Obesity-Associated CSC Enrichment and EMT in Preclinical TNBC Models

Obesity is associated with poor prognosis in triple-negative breast cancer (TNBC). Preclinical models of TNBC were used to test the hypothesis that increased leptin signaling drives obesity-associated TNBC development by promoting cancer stem cell (CSC) enrichment and/or epithelial-to-mesenchymal transition (EMT). MMTV-Wnt-1 transgenic mice, which develop spontaneous basal-like, triple-negative mammary tumors, received either a control diet (10% kcal from fat) or a diet-induced obesity regimen (DIO, 60% kcal from fat) for up to 42 weeks (n = 15/group). Mice were monitored for tumor development and euthanized when tumor diameter reached 1.5 cm. Tumoral gene expression was assessed via RNA sequencing (RNA-seq). DIO mice had greater body weight and percent body fat at termination than controls. DIO mice, versus controls, demonstrated reduced survival, increased systemic metabolic and inflammatory perturbations, upregulated tumoral CSC/EMT gene signature, elevated tumoral aldehyde dehydrogenase activity (a CSC marker), and greater leptin signaling. In cell culture experiments using TNBC cells (murine: E-Wnt and M-Wnt; human: MDA-MB-231), leptin enhanced mammosphere formation, and media supplemented with serum from DIO versus control mice increased cell viability, migration, invasion, and CSC- and EMT-related gene expression, including Foxc2, Twist2, Vim, Akt3, and Sox2 In E-Wnt cells, knockdown of leptin receptor ablated these procancer effects induced by DIO mouse serum. These findings indicate that increased leptin signaling is causally linked to obesity-associated TNBC development by promoting CSC enrichment and EMT.Implications: Leptin-associated signals impacting CSC and EMT may provide new targets and intervention strategies for decreasing TNBC burden in obese women. Mol Cancer Res; 16(5); 869-79. ©2018 AACR.

Adipocyte-Tumor Cell Metabolic Crosstalk in Breast Cancer

The tumor stroma is a heterogeneous ecosystem comprising matrix, fibroblasts, and immune cells and has an important role in cancer progression. Adipocytes constitute a major component of breast stroma, and significant emerging evidence demonstrates a reciprocal metabolic adaptation between stromal adipocytes and breast cancer (BC) cells. Recent observations promote a model where adipocytes respond to cancer cell-derived endocrine and paracrine signaling to provide metabolic substrates, which in turn drive enhanced cancer cell proliferation, invasion, and treatment resistance. Further defining the mechanisms that underpin this dynamic interaction between stromal adipocytes and BC cells, especially in the context of obesity, may identify novel therapeutic strategies. These will become increasingly important in addressing the clinical challenges presented by obesity and metabolic syndromes.

The Influence Of Obesity On Results Of AT (Doxorubicin Plus Docetaxel) Neoadjuvant Chemotherapy In Locally Advanced Breast Cancer Patients

The achieve pathologic complete response is proven to be the most important parameter of prognosis. Thereports evaluating the impact of obesity on the obtained pathologic response to chemotherapy are unequal. The aim of the study was to evaluate in locally advanced breast cancer patients, treated with AT(doxorubicin plus docetaxel) neoadjuvant chemotherapy: 1. The relationship of obesity with obtaining pathological response. 2. The relationship of obesity and free of disease recurrence survival (DFS) and overall survival (OS) associated with the tumour.

MATERIAL AND METHODS

A retrospective study was carried out in a group of 105 patients with locally advanced breast cancer, treated with AT neoadjuvant chemotherapy and then treated with radical surgery. Two variants of pathological response have been adopted: a pCR (T0N0) and pCR1 (TisN0, TxN1, T1N0, T1N1, T0N1). The relationship of obesity with pathological response and survival was investigated.

RESULTS

In univariate analysis the pCR1 was obtained with its arising from the borderline of statistical significance with lower incidence of obesity. In pCR1 multivariate analysis, negative pCR1 relationship with obesity was on the borderline of the statistical significance. The multivariate analysis showed a significant negative association OS with obesity (p=0.047) and positive with the occurrence of menopause (p = 0.029).

CONCLUSIONS

In patients with locally advanced breast cancer treated with AT neoadjuvant chemotherapy. 1. Obesity seems to be an independent and unfavourable predictor of the lack of obtaining pCR1 pathological response 2. In the multivariate analysis, the obesity was a significant independent factor related to shorter OS.

Impact of race, ethnicity, and BMI on achievement of pathologic complete response following neoadjuvant chemotherapy for breast cancer: a pooled analysis of four prospective Alliance clinical trials (A151426)

Previous studies demonstrated poor response to neoadjuvant systemic therapy (NST) for breast cancer among black women and women who are overweight or obese, but this may be due to chemotherapy underdosing. We assessed associations of race, ethnicity, and body mass index (BMI) with pathologic complete response (pCR) in clinical trial populations. 1797 women enrolled in four NST trials (CALGB 40601, 40603; ACOSOG Z1041, Z1071) were included. Tumor subtypes were defined by estrogen receptor (ER) and HER2 status. Logistic regression generated odds ratios (OR) and 95 % confidence intervals (CI) for the associations of race, ethnicity, and BMI with in-breast pCR adjusting for subtype, study arm, lymph node status, tumor size, and tumor grade. 253 (14.1 %) were black, 199 (11.1 %) Hispanic, 520 (28.9 %) overweight, and 743 (41.4 %) obese. Compared to whites, Blacks and Hispanics were more likely to be obese and Blacks were more likely to have triple-negative cancer. pCR rates differed significantly by tumor subtype. In multivariate analyses, neither race (black vs white: OR 1.18, 95 % CI 0.85-1.62) nor ethnicity (Hispanic vs non-Hispanic; OR 1.30, 95 % CI 0.67-2.53) were significant predictors of pCR overall or by subtype. Overweight and obese women had lower pCR rates in ER+/HER2+, but higher pCR rates in ER-/HER2+ cancers. There was no difference in pCR according to race or ethnicity. Overall, there was no major difference in pCR rates by BMI. These findings suggest that pCR with optimally dosed NST is a function of tumor, rather than patient, biology.

Effect of Body Mass Index- and Actual Weight-Based Neoadjuvant Chemotherapy Doses on Pathologic Complete Response in Operable Breast Cancer

INTRODUCTION

The effect of body mass index (BMI) and chemotherapy dose reduction on pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) for locoregional breast cancer remains unclear. Contemporary studies have reported largely on trial populations and used dose-capping.

PATIENTS AND METHODS

Patient registries at the University of Iowa were queried to identify patients with operable breast cancer who received NAC. Dose reductions were calculated for taxanes (T), anthracyclines (A) and non-A-T chemotherapy. Clinical-pathologic characteristics, chemotherapy dose reductions, and adverse events were compared between normal (BMI <25) and overweight/obese patients (BMI ≥25). Additionally, the synergistic effect of BMI and chemotherapy dose reduction on pCR was assessed.

RESULTS

Of 171 eligible patients, 112 were overweight/obese. Chemotherapy dosing was capped in 2 patients; all others initiated full weight-based treatment. Overweight/obese patients required more frequent taxane (44.6% vs. 25.4%; P = .01) and any chemotherapy dose reductions (50.9% vs. 33.9%; P = .03). pCR was attained in 29.2% of patients. In a multivariable model, the interaction term for BMI as a continuous variable and any chemotherapy dose reduction was significant independent of the clinical stage and tumor receptor status (P = .04). For obese patients, any chemotherapy dose reduction was significantly associated with increased odds of not attaining pCR.

CONCLUSION

During NAC, overweight/obese patients more often have chemotherapy dose reductions. Chemotherapy dose reduction in obese patients was a powerful predictor of not attaining pCR. This was not seen for normal or overweight patients. Opportunities might exist to improve pCR rates in this higher-risk group.

Obesity is an independent prognostic factor of decreased pathological complete response to neoadjuvant chemotherapy in breast cancer patients

PURPOSE

The relation between higher body mass index (BMI) and pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in breast cancer (BC) is a controversial issue according to the data of Western and Asian patients. The aim of this study is to evaluate BMI and pCR to NAC and discuss the importance of pCR outcomes in Turkish BC patients as a bridging country between Europe and Asia.

PATIENTS AND METHODS

Of the 4423 BC patients diagnosed between the years 1994 and 2015 in Hacettepe University Cancer Institute, 295 female patients with stage II and III BC were enrolled in the study. Three different group divisions were done according to patients' BMI as normal or underweight (N/U) patients (BMI <25 kg/m²), overweight (OW) patients (BMI = 25-29.9 kg/m²) and obese (OB) patients (BMI ≥30 kg/m²). BC subtypes were defined as luminal-like (ER/PR-positive and HER2-negative), HER2/luminal (ER/PR-positive and HER2-positive), HER2-type (ER/PR-negative and HER2-positive), and triple-negative (TNBC; ER/PR- and HER2-negative). The analysis of overall survival (OS) and recurrence-free survival (RFS) was performed according to Kaplan-Meier method. The Log-rank test was used to compare the subgroup analysis and logistic regression analysis to determine the independent prognostic factors.

RESULTS

In this study, a total number of 93 (31.5%) patients were N/U, 107 (36.3%) patients were OW and 95 (32.2%) patients were OB. Among groups, except for the age, no baseline clinicopathological differences were found. In 70 (23.7%) patients, pCR was achieved. pCR rates in N/U, OW and OB were 31.2%, 22.4%, and 17.9% respectively, showing a considerable trend towards significance (P = 0.09 in chi-square test). In the multivariate logistic regression analysis, obesity was an independent adverse prognostic feature on pCR to NAC compared to N/U patients (OR, 0.34; 95% CI, 0.13 to 0.85, P = 0.02). The recurrence rates were slightly increased with the increase of BMI (N/U = 24.7%, OW = 29.0% and OB = 40%; P = 0.06 respectively). Median RFS was significantly higher in N/U group compared to OB patients (150 vs. 76 months respectively, P = 0.03) and was also higher in pCR group compared to non-pCR patients (151 vs. 77 months P = 0.004). Median OS was significantly higher in N/U patients compared to OB patients (N/U = not reached, OW = 211 and OB = 114 months; P = 0.01) and was also higher in pCR group compared to non-pCR patients (not reached vs. 211 months P = 0.04). In Cox regression analysis; pCR, histopathological grade and TNBC were found as independent prognostic factors on OS (HR, 0.29; 95% CI, 0.11 to 0.79, P = 0.015, HR, 2.09; 95% CI, 1.14 to 3.83, P = 0.017, HR, 1.95; 95% CI, 1.01 to 3.77, P = 0.046, respectively).

CONCLUSION

It was observed that obesity was an important independent prognostic factor which has an adverse effect on pCR. Moreover it causes decreasing RFS and OS in BC patients who had received NAC. The probability of inefficient treatment in obese patients should be considered.

Associations between metabolic syndrome, breast cancer recurrence, and the 21-gene recurrence score assay

The 21-gene recurrence score (RS) assay is prognostic in estrogen receptor-positive (HR+), HER2-negative, node-negative breast cancer (BC). The interaction between RS and host factors including metabolic syndrome (MS) is unclear. MS conditions such as obesity have been associated with worse BC prognosis. The aim of this study was to identify associations between presence of MS conditions and RS group or breast cancer recurrence. Demographic, pathologic, and treatment data, MS criteria, and menopausal status were abstracted from medical records of women with stage I-II, HR+, HER2-negative BC evaluated with the RS assay at a single institution since 2005. MS was defined as presence of ≥3 of the following within 2 years of diagnosis: body mass index ≥27.7 kg/m(2); hypertension; impaired fasting glucose; HDL <50 mg/dL; hypertriglyceridemia. Of 533 eligible women, 22 % had MS. MS was more common in post- vs premenopausal women (30 vs 9 %; P < 0.0001). There was no significant association between RS group and overall MS status or any individual criterion, controlling for stage, and no association after stratification by menopausal status. Postmenopausal status was associated with higher RS group (P = 0.039), independent of stage. With 4.2-year median follow-up, no association between disease recurrence and MS was identified. Although MS has been associated with worse BC outcomes, we were unable to identify associations between RS group and MS criteria. Identification of prognostic factors other than RS that underlie this higher risk will be important for optimizing breast cancer treatment decision-making in patients with MS.

BMI and Pathologic Complete Response to Neoadjuvant Chemotherapy in Breast Cancer: A Study and Meta-Analysis

INTRODUCTION

There is only limited data from clinical practice on the relevance of body mass index (BMI) on pathologic complete response (pCR) following neoadjuvant chemotherapy (NAC) in patients with breast cancer (BC).

PATIENTS AND METHODS

The impact of BMI on pCR and survival outcome was examined in 324 patients with primary non-metastatic BC. An additional meta-analysis was performed on the current data and relevant previously published studies in clinical practice.

RESULTS

Multivariable regression analysis identified lymph vascular invasion (odds ratio [OR], 0.05; 95% confidence interval [CI], 0.01-0.18; P = .0000), grading 3 (OR, 3.12; 95% CI, 1.59-6.12; P = .0009), and HER2/neu status (OR, 4.76; 95% CI, 1.86-12.18; P = .011) as independent factors for pCR after NAC. There was no association between pCR and continuous or categorical BMI. Various additional subgroup analyses of molecular BC subtypes (triple-negative, luminal-like, HER2-luminal, HER2-like) and BMI also showed no association. These findings were confirmed by the meta-analysis. Except for one subgroup analysis in which overweight and obese patients were combined as one group, no association between BMI and pCR as well as survival outcome was found.

CONCLUSIONS

BMI was not established as a relevant clinical factor. Only lymph vascular invasion, grading 3, luminal-like, and HER2/like BC subtype showed predictive and prognostic impact in patients with BC receiving NAC.

Obesity Suppresses Estrogen Receptor Beta Expression in Breast Cancer Cells via a HER2-Mediated Pathway

Obesity is associated with a worse breast cancer prognosis, while greater breast tumor estrogen receptor beta (ERβ) expression is correlated with improved therapy response and survival. The objective of this study was to determine the impact of obesity on breast cancer cell ERβ expression, which is currently unknown. We utilized an in vitro model of obesity in which breast cancer cells were exposed to patient serum pooled by body mass index category (obese (OB): ≥30 kg/m2; normal weight (N): 18.5-24.9 kg/m2). Four human mammary tumor cell lines representing the major breast cancer subtypes (SKBR3, MCF-7, ZR75, MDA-MB-231) and mammary tumor cells from MMTV-neu mice were used. ERβ expression, assessed by qPCR and western blotting, was suppressed in the two HER2-overexpressing cell lines (SKBR3, MMTV-neu) following OB versus N sera exposure, but did not vary in the other cell lines. Expression of Bcl-2 and cyclin D1, two genes negatively regulated by ERβ, was elevated in SKBR3 cells following exposure to OB versus N sera, but this difference was eliminated when the ERβ gene was silenced with siRNA. Herceptin, a HER2 antagonist, and siRNA to HER2 were used to evaluate the role of HER2 in sera-induced ERβ modulation. SKBR3 cell treatment with OB sera plus Herceptin increased ERβ expression three-fold. Similar results were obtained when HER2 expression was silenced with siRNA. OB sera also promoted greater SKBR3 cell viability and growth, but this variance was not present when ERβ was silenced or the cells were modified to overexpress ERβ. Based on this data, we conclude that obesity-associated systemic factors suppress ERβ expression in breast cancer cells via a HER2-mediated pathway, leading to greater cell viability and growth. Elucidation of the mechanism(s) mediating this effect could provide important insights into how ERβ expression is regulated as well as how obesity promotes a more aggressive disease.

Use of Insulin and Mortality from Breast Cancer among Taiwanese Women with Diabetes

Background. To evaluate whether insulin use was predictive for mortality from breast cancer in Taiwanese women with diabetes mellitus. Methods. A total of 48,880 diabetic women were followed up to determine the mortality from breast cancer during 1995-2006. Cox models were used, considering the following independent variables: age, sex, diabetes type, diabetes duration, body mass index, smoking, insulin use, and area of residence. Insulin use was also considered for its duration of use at cutoffs of 3 years and 5 years. Results. Age was a significant predictor in all analyses. The multivariable-adjusted hazard ratio (95% confidence interval, P value) for insulin use without considering the duration of use was not statistically significant (1.339 [0.782-2.293, P = 0.2878]). Compared with nonusers, insulin users showed the following adjusted hazard ratios for insulin use <3 years, ≥3 years, <5 years, and ≥5 years: 0.567 (0.179-1.791, P = 0.3333), 2.006 (1.102-3.653, P = 0.0228), 1.045 (0.505-2.162, P = 0.9048), and 1.899 (0.934-3.860, P = 0.0763). Conclusions. Insulin use (mainly human insulin) for ≥3 years may be associated with a higher risk of breast cancer mortality.

Targeting the COX-2 Pathway to Improve Therapeutic Response in the Obese Breast Cancer Patient Population

Multiple studies have demonstrated that obesity is associated with a worse outcome for all breast cancer subtypes and that obese breast cancer patients do not respond as well as normal weight patients to aromatase inhibitor treatment and chemotherapy. While a number of mechanisms have been proposed to explain this link, recent studies have provided evidence that elevated local cyclooxygenase-2 (COX-2) expression and the resulting increase in prostaglandin E2 (PGE2) production may play an important role. COX-2 upregulation in breast tumors is associated with a poor prognosis, a connection generally attributed to PGE2's direct effects on apoptosis and invasion as well as its stimulation of pre-adipocyte aromatase expression and subsequent estrogen production. Research in this area has provided a strong foundation for the hypothesis that COX-2 signaling is involved in the obesity-breast cancer link, and further study regarding the role of COX-2 in this link is warranted.

Impact of body mass index on neoadjuvant treatment outcome: a pooled analysis of eight prospective neoadjuvant breast cancer trials

Obesity is associated with an increased risk of breast cancer (BC) and poorer outcome. We assessed the impact of body mass index (BMI) on pathological complete response (pCR), disease-free (DFS), and overall survival (OS), according to BC subtypes in patients with primary BC treated with neoadjuvant chemotherapy. 8,872 patients with primary BC from eight neoadjuvant trials were categorized according to BMI: underweight (<18.5 kg/m(2)), normal weight (18.5 to <25 kg/m(2)), overweight (25 to <30 kg/m(2)), obese (30 to <40 kg/m(2)), and very obese (≥40 kg/m(2)). BC subtypes were defined as luminal-like (ER/PgR-positive and HER2-negative), HER2/luminal (ER/PgR-positive and HER2-positive), HER2-like (ER/PgR-negative and HER2-positive), and triple-negative (TNBC; ER/PgR- and HER2-negative). pCR rate was higher in normal weight patients compared with all other BMI groups (P = 0.003). Mean DFS and OS were shorter in obese (87.3 months, P = 0.014 and 94.9 months, P = 0.001, respectively) and very obese (66.6 months, P < 0.001 and 75.3 months, P < 0.001, respectively) compared with normal weight patients (91.5 and 98.8 months, respectively) which was confirmed by subpopulation treatment effect pattern plot analyses and was consistent in luminal-like and TNBC. No interaction was observed between BMI and pCR. Normal weight patients experienced less non-hematological adverse events (P = 0.002) and were more likely to receive full taxane doses (P < 0.001) compared with all other BMI groups. In multivariable analysis, the dose of taxanes was predictive for pCR (P < 0.001). Higher BMI was associated with lower pCR and a detrimental impact on survival. Normal weight patients had the best compliance to chemotherapy and received the highest taxane doses, which seems to be related with treatment outcomes.

Impact of weight change during neoadjuvant chemotherapy on pathologic response in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an uncommon but aggressive subtype of breast cancer. Obesity has been associated with an increased risk of breast cancer and worse prognosis. Some studies suggest that obese patients are less likely to achieve pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) and experience worse overall survival. Ki-67 is a proliferation marker that correlates with tumor aggressiveness. The goal of this study was to examine the impact of weight change during NCT for TNBC on pathologic response and Ki-67 reduction. Retrospective review identified 173 TNBC patients treated between 2004 and 2011. Data were collected on patient demographics, pre- and post-NCT body mass index (BMI), Ki-67, and pCR. Data analysis was performed using the two-tailed Student's t-test, analysis of variance (ANOVA), and Fisher's exact test. Sixty-six patients met final study criteria. Forty-three patients lost weight during chemotherapy and 23 gained weight. Patients in the weight gain group were significantly younger (P = 0.0013). There was no significant difference between the two groups in terms of Ki-67 reduction (P = 0.98) or pCR (P = 0.58). When patients were separated into normal weight (BMI<25 kg/m(2) ), overweight (BMI ≥ 25 and <30 kg/m(2) ), and obese (BMI ≥ 30 kg/m(2) ), there was no significant difference in Ki-67 among those groups either before or after NCT. The degree of obesity did not have a significant impact on Ki-67 reduction. Weight change during NCT does not appear to correlate with Ki-67 change or achieving pCR in TNBC. This may reflect the nature of this subtype of breast cancer that is less responsive to the hormonal effects that adipose tissue exerts on cancer cell proliferation.

Association of Body Mass Index Changes during Neoadjuvant Chemotherapy with Pathologic Complete Response and Clinical Outcomes in Patients with Locally Advanced Breast Cancer

The purpose of this study was to determine the association between body mass index (BMI) measurements (baseline BMI and changes in BMI during neoadjuvant systemic treatment [NST]) and clinical efficacy (pathologic complete response [pCR] rate and survival outcomes) in locally advanced breast cancer (LABC). We hypothesized that high baseline BMI and increases in BMI during NST are associated with lower pCR rates and poorer clinical outcomes in LABC.

We retrospectively reviewed the medical records of 1002 patients, 204 with primary inflammatory breast cancer (IBC) and 798 with stage III non-IBC, who underwent standard NST and definitive surgery between November 1, 2006, and December 31, 2012.

The median follow-up time for the survivors was 19.6 months (0.4 - 67.8 months). The pCR rates of patients whose BMI increased or decreased were 23.2% and 18.1%, respectively, (p=0.048). The unadjusted overall survival (OS) was significantly better in the group with increased BMI (p=0.006). However, increased BMI was not an independent predictor of pCR and clinical outcomes (recurrence-free survival and OS) after adjusting for other clinical variables. In subset analyses, increased BMI as a continuous variable was an independent predictor of higher pCR rates in the normal BMI/underweight group (odds ratio [OR]=1.35, 95% confidence interval [CI]: 1.06-0.71, p=0.015). Increased BMI (BMI change ≥0 vs. <0) was also an independent predictor of pCR (OR=1.65, 95% CI: 1.00-2.72, p=0.049) in the postmenopausal group.

Our results show that increasing BMI shows improved clinical outcome in terms of better pCR rates in normal BMI/underweight group and in the postmenopausal group. These results contradict previously reported findings on the association between high BMI and poor clinical efficacy regarding pCR rate and survival outcomes in early-stage breast cancer. Thus, the role of BMI in breast cancer may depend on patients' clinical characteristics such as advanced stage.

Myelotoxicity of carboplatin is increased in vivo in db/db mice, the animal model of obesity-associated diabetes mellitus

PURPOSE

Some authors observed increased carboplatin-associated myelotoxicity in obese patients which was exclusively attributed to elevated AUC. To investigate the potential contribution of functional changes of cells primarily responsible for myelopoiesis, granulocyte-macrophage progenitors (CFU-GM) were studied in obesity-associated diabetes mellitus (DMT2).

METHODS

The most frequently used animal model of human obesity with DMT2 is db/db mouse. Cellularity, frequency of CFU-GM and total CFU-GM content of femoral bone marrow were measured after 100 mg/kg dose of carboplatin in vivo. To exclude influence of pharmacokinetic changes, direct toxicity of carboplatin on CFU-GM was also determined in vitro and was compared with other anticancer agents, namely doxorubicin, 5-fluorouracil and 4-thiouridylate.

RESULTS

After intraperitoneal administration of carboplatin, each measured characteristics of bone marrow function was more significantly suppressed and the induced neutropenia was more serious in db/db mice than in the controls. The increased myelotoxicity seemed to be a direct effect on myeloid progenitor cells since their increased in vitro sensitivity was found in db/db mice. This was not specific for carboplatin, a similar double to fivefold increase in myelotoxicity of each cytotoxic drug with different mechanism of action was observed. Four-thiouridylate, a promising antileukemic molecule with good therapeutic index, was by far the least toxic for CFU-GM of db/db mice.

CONCLUSIONS

A serious disorder of CFU-GM progenitors was suggested in obese mice with DMT2, which eventually might lead to more severe myelotoxicity and neutropenia. Weight loss and normalization of glucose homeostasis may be important before chemotherapy of malignant diseases in obesity with DMT2.

The association between the 844ins68 polymorphism in the CBS gene and breast cancer

INTRODUCTION

The cystathionine beta synthase (CBS) gene plays an important role in homocysteine metabolism because it catalyzes the first step of the transsulfuration pathway, during which homocysteine is converted to cystathionine. Polymorphisms of CBS have been associated with cancer.

MATERIAL AND METHODS

We examined the role of the 844ins68 polymorphism by comparing the genotypes of 371 healthy Mexican women with the genotypes of 323 Mexican women with breast cancer (BC).

RESULTS

The observed genotype frequencies for controls and BC patients were 1% and 2% for Ins/Ins, 13% and 26% for W/Ins, and 86% and 72% for W/W, respectively. We found that the odds ratio (OR) was 2.2, with a 95% confidence interval (95% CI) of 1.5-3.3, p = 0.0001. The association was also evident when comparing the distribution of the W/Ins-Ins/Ins genotypes in patients in the following categories: 1) menopause and high γ-glutamyltransferase (GGT) levels (OR of 2.17, 95% CI: 1.17-4.26, p = 0.02), 2) chemotherapy response and high lactate dehydrogenase (LDH) levels (OR 2.2, 95% CI: 1.08-4.4, p = 0.027), 3) chemotherapy response and high GGT levels (OR 2.46, 95% CI: 1.2-4.8, p = 0.007), and 4) body mass index (BMI) and III-IV tumor stage (OR 3.2, 95% CI: 1.2-8.3, p = 0.013).

CONCLUSIONS

We conclude that the genotypes W/Ins-Ins/Ins of the 844ins68 polymorphism in the CBS gene contribute significantly to BC susceptibility in the analyzed sample from the Mexican population.