BackgroundHigh triglycerides and low levels of high density lipoprotein (HDL)-cholesterol are observed to promote tumor growth. However, whether breast cancer heterogeneity may explain the contradictory influence of triglycerides and cholesterol observed on breast cancer prognosis remains unclear.MethodsA population-based survival study among 464 breast cancer cases identified within the Tromsø study was conducted. Pre-diagnostic triglycerides, total-cholesterol and HDL-cholesterol were measured, and detailed clinical and histopathological data were obtained. Using tissue microarray, all breast cancer cases were reclassified into the following subtypes: Luminal A, Luminal B, HER2-enriched, and triple negative breast cancer (TNBC). Multivariable Cox proportional hazards regression models were used to study the associations between pre-diagnostic lipids and breast cancer recurrence, mortality, and survival.ResultsA total of 464 breast cancer patients, with mean age at diagnosis of 57.9 years, were followed for a mean 8.4 years. TNBC patients in the highest tertile of triglycerides (≥ 1.23 mmol/l) had 3 times higher overall mortality compared to TNBC patients in the lowest tertile (≤ 0.82 mmol/l) (HR 2.99, 95% CI 1.17–7.63), and the 5-year overall survival was 19% lower for TNBC patients in the highest vs. lowest tertile of triglycerides (65% vs. 84%). TNBC patients in the highest tertile of the HDL-cholesterol/total-cholesterol ratio (≥0.35), compared to those in the lowest tertile (≤0.27), had a 67% reduced overall mortality risk (HR 0.33, 95% CI 0.12–0.89). No associations were observed between lipids and prognostic outcome among breast cancer patients overall, or among patients with luminal A and luminal B subtypes. Among HER2-enriched patients, pre-diagnostic triglyceride level was inversely associated with overall mortality.ConclusionOur study suggests that pre-diagnostic triglycerides and the HDL-cholesterol/total-cholesterol ratio may independently provide unique information regarding prognostic outcome among triple negative breast cancer patients. However, a small sample size underlines the need for additional studies.Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4568-2) contains supplementary material, which is available to authorized users.

Inflammation may initiate and promote breast cancer development, and be associated with elevated circulating levels of inflammation markers. A total of eight 130 initially healthy women, participated in the population-based Tromsø study (1994-2008). Pre-diagnostic high-sensitivity C-reactive protein (hs-CRP) was assessed. During 14.6 years of follow-up, a total of 192 women developed invasive breast cancer. These cases were followed for additional 7.2 years. Detailed medical records were obtained. We observed an overall positive dose-response relationship between pre-diagnostic hs-CRP and breast cancer risk (hazard ratio (HR) = 1.06, 95 % CI 1.01-1.11). Postmenopausal women with above median levels of hs-CRP (>1.2 mg/l) had a 1.42 (95 % CI 1.01-2.00) higher breast cancer risk compared to postmenopausal women with hs-CRP below median. Postmenopausal women, who were hormone replacement therapy non-users, and were in the middle tertile (0.8-1.9 mg/l), or highest tertile of hs-CRP (>1.9 mg/l), had a 2.31 (95 % CI 1.31-4.03) and 2.08 (95 % CI 1.16-3.76) higher breast cancer risk, respectively, compared with women in the lowest tertile. For each unit increase in pre-diagnostic hs-CRP levels (mg/l), we observed an 18 % increase in disease-free interval (95 % CI 0.70-0.97), and a 22 % reduction in overall mortality (95 % CI 0.62-0.98). Our study supports a positive association between pre-diagnostic hs-CRP and breast cancer risk. In contrast, increased pre-diagnostic hs-CRP was associated with improved overall mortality, but our findings are based on a small sample size, and should be interpreted with caution.

Purpose Whether an unfavorable lifestyle not only affects breast cancer risk, but also influences age at onset of breast cancer and survival, is under debate. Methods In a population-based cohort, the Energy Balance and Breast Cancer Aspects throughout life (EBBA-Life) study, a total of 17,145 women were included. During follow-up, 574 women developed invasive breast cancer. Breast cancer cases were followed for an additional 9.1 years. Detailed medical records were obtained. Cox's proportional hazard regression models were used to study the association between pre-diagnostic lifestyle factors (weight, physical activity, alcohol use, smoking, and hypertension), breast cancer risk, age at diagnosis, and survival. Results At study entry, 34.3% of the participating women were overweight and 30.7% were physically inactive. Mean age at breast cancer diagnosis was 58.0 years, and 78.9% of the tumors were estrogen receptor positive. Among menopausal women who did not use hormone therapy and had an unfavorable lifestyle (3-5 unfavorable factors), compared with women who had a favorable lifestyle, we observed a twofold higher risk for postmenopausal breast cancer (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.23-3.69), and they were 3.4 years younger at diagnosis (64.8 versus 68.2 years, P = 0.032). Breast cancer patients with an unfavorable lifestyle, compared with patients with a favorable lifestyle, had almost a two times higher overall mortality risk (HR 1.96, 95% CI 1.01-3.80). Conclusions Our study supports a healthy lifestyle improving breast cancer prevention, postponing onset of disease, and extending life expectancy among breast cancer patients.

Background: Migrant studies have shown an increase in breast cancer incidence rates among immigrants moving from a breast cancer low-incidence to a high-incidence country. However, 30 years after immigration, it remains equivocal to what degree metabolic factors and ethnic disparities affect breast cancer development and treatment. Methods: Using Cox regression models, we examined the association between ethnicity and breast cancer development, and whether this association varied by pre-diagnostic metabolic profiles among 13 802 women, aged 20-75 years, participating in the population-based Oslo Ethnic Breast Cancer Study. Ethnicity was categorized into: women of Western European descent (reference population) and women of non-western ethnicity (ethnic minority). The ethnic minority women were further subclassified into three groups: 1) South Asian, 2) Middle East and North African, and 3) all other non-western origin women. We defined four pre-diagnostic unfavorable metabolic factors (above median body mass index (>24.6 kg/m2), waist:hip ratio (>0.79), triglyceride:HDL-cholesterol ratio (>0.73), and blood pressure (>96.5 mmHg)), which were combined to define three metabolic profiles: (0-2, 3, and 4 unfavorable metabolic factors). A total of 557 women developed invasive breast cancer during a mean 16.5 years of follow-up. Detailed medical records were obtained. Results: Among women with an unfavorable metabolic profile, South Asian women, compared with Western European women, had a 2.3 times higher breast cancer risk (HR 2.30, 95% CI 1.18-4.49). Furthermore, the ethnic minority women, compared with the Western European women, were suggestively more likely to present with triple-negative breast cancer (OR 2.11, 95% CI 0.97-4.61), and less likely to complete all courses of planned taxane treatment (OR 0.26, 95% CI 0.08-0.82). No differences by ethnicity were observed in physicians’ decisions of planned breast cancer treatment, Conclusions: Our results support that metabolic factors, including body composition, serum lipids and blood pressure, are important when balancing breast cancer prevention and disease management among non-western women migrating from a breast cancer low-incidence to a high-incidence country. However, larger studies are needed. Citation Format: Trygve Lofterød, Hanne Frydenberg, Marit Veierød, Anne Karen Jenum, Jon B Reitan, Erik Wist, Inger Thune. The influence of metabolic factors, migration, and ethnic disparities on breast cancer risk and treatment [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-14-08.

e23043 Serum metabolism during breast cancer treatment Background: Breast cancer treatment may include surgery, systemic therapy and radiation, often involving side-effects. Many patients experience weight gain during treatment, which is associated with decreased survival rates1. The purpose of this study was to describe serum metabolic alterations in breast cancer patients undergoing treatment, and relate these alterations to weight gain during treatment. Methods: This pilot study includes 60 breast cancer patients, aged 35-75 years, with histologically verified stage I/II disease. All patients underwent tumor surgery, and were treated according to national guidelines. Samples were collected before and 6 months after surgery, and analyzed by MR spectroscopy (MRS) and mass spectrometry (MS). 170 metabolites and 105 lipoprotein subfractions were quantified by combined MRS and MS analyses. Results: Multilevel PLS-DA showed significant alterations in serum metabolite profiles post-treatment, both in patients receiving (n = 35) and not receiving (n = 25) chemotherapy (classification accuracy: 86.7% and 77.0%, resp., p < 0.001). Lipoprotein profiles were also significantly altered in both groups (p < 0.001). Chemotherapy recipients had decreased levels of citrate, ornithine, and methionine after treatment, while non-recipients had increased levels of glutamate, alanine, proline and two biogenic amines, and decreased levels of acylcarnitines. 17/52 patients (32.7%) gained weight (≥ 1.5 kg) during treatment. Weight gain was predicted from pre-treatment samples with accuracy 67.0% (p = 0.020). Weight gain patients had lower levels of three acylcarnitines and 20 phosphocholines, and higher levels of lysine and isoleucine, suggesting aberrant lipid and amino acid metabolism. Weight gain was also reflected in the post-treatment samples (accuracy 66.8%, p = 0.015), with weight gain patients having higher levels of five acylcarnitines, and lower levels of glycine, isoleucine and valine. Conclusions: This study indicates that treatment induces changes in serum metabolite levels. Patients gaining weight had significantly different metabolite profiles than those not gaining weight both before and after treatment. 1. Chan et al, Ann Oncol 25: 1901-14, 2014.