The effect of modifiable risk factors on breast cancer aggressiveness among black and white women

The impact of high intensity interval training in a diverse group of cancer survivors: CAPABLE, a pilot study

Purpose

Given the well-documented benefits of regular exercise to cancer survivors, current American Cancer Society guidelines recommend that patients engage in a minimum of 150 min per week of moderate-to-vigorous physical activity with a minimum of two days of strength training. However, few survivors meet this goal, particularly among minorities.

Methods

The CAPABLE study is a single-arm, pilot exercise intervention that introduced 48 cancer survivors to a high intensity interval and strength training program three days a week for 12 weeks. We evaluated the impact of this unique training method on bodyweight, % body fat, serum markers correlated with an adverse cardiometabolic profile and health-related quality of life (HRQoL). Measures were summarized at baseline and program exit. Paired t-tests were used to assess change in each of these measures over time.

Results

We observed losses in weight, body mass index, and % body fat, and glycosylated hemoglobin (HbA1c) levels over 12-weeks. There were also clinically meaningful improvements in reported overall HRQoL (FACTG total change +9.5 (95% CI, 4.6, 14.4)) and in each one of the individual domains (physical, social, emotional, and functional well-being).

Conclusions

We observed meaningful improvements in body composition, HbA1c and quality of life over 12 weeks among cancer survivors participating in a high-intensity interval training program. Future work will include a control arm for comparison and address barriers to participation and adherence which will be important in using this intervention and others like it to improve outcomes and reduce cancer health disparities.

Associations between Pre-Diagnostic Physical Activity with Breast Cancer Characteristics and Survival

Physical activity (PA) is known to reduce breast cancer (BC) risk and improve patient prognosis. However, the association between pre-diagnostic PA and the aggressiveness of BC is unclear. We investigated the associations between PA, BC tumour characteristics, and survival. This retrospective observational study included 7688 BC patients from the Singapore Breast Cancer Cohort (2010−2016). PA information from the questionnaire included intensity (light/moderate/vigorous) and duration (<1 h/1−2 h/>2 h per week). A PA score (1−5) incorporating intensity and duration was calculated. Associations between PA score and tumour characteristics such as stage, histological grade, nodal and hormone receptor status were examined using multinomial regression. Moreover, 10-year overall survival was estimated using Cox regression analysis in 6572 patients after excluding patients with invalid survival data and stage IV disease. Breast tumours associated with higher PA score were more likely to be non-invasive (ORinvasive vs. non-invasive(reference) [95% CI]: 0.71 [0.58−0.87], p-trend = 0.001), of lower grade (ORpoorly vs. well differentiated(reference): 0.69 [0.52−0.93], p = 0.014), ER-positive (ORER-negative vs. ER-positive(reference): 0.94 [0.89−1.00], p-trend = 0.049), PR-positive (ORPR-negative vs. PR-positive(reference): 0.82 [0.67−0.99], p = 0.041), HER2-negative (ORHER2-negative vs. HER2-positive(reference): 1.29 [1.02−1.62], p-trend = 0.002), and less likely to be of HER2-overexpressed subtype (ORHER2-overexpressed vs. Luminal A(reference): 0.89 [0.81−0.98], p-trend = 0.018). These associations (odds ratios) were more pronounced among post-menopausal patients. A higher PA score did not improve survival. Higher levels of pre-diagnostic PA were associated with less aggressive tumours in BC patients. This illustrated another benefit of PA in addition to its known role in BC risk reduction.

Association of Insulin Resistance and Higher Oncotype DX™ Recurrence Score

BACKGROUND

Black women with breast cancer have a worse overall survival compared with White women; however, no difference in Oncotype DX™ (ODX) recurrence scores has been observed to explain this health disparity. Black women are also disproportionately affected by insulin resistance. We evaluated whether insulin resistance is associated with a higher ODX recurrence score and whether there is a difference between White and Black women to explain disparate clinical outcomes.

METHODS

A subgroup analysis of patients in a multi-institutional cross-sectional study evaluating differences in insulin resistance between White and Black women was performed. Women diagnosed with a new hormone receptor-positive, HER2/neu-negative breast cancer with an ODX recurrence score were identified. Fasting blood glucose and insulin measurements were used to calculate the homeostatic model assessment of insulin resistance (HOMA-IR) score, a method for assessing insulin resistance, and compared against ODX scores.

RESULTS

Overall, 412 women (358 White women, 54 Black women) were identified. Compared with White women, Black women had a higher body mass index (30 vs. 26 kg/m², p < 0.0001), higher HOMA-IR score (2.4 vs. 1.4, p = 0.004), and more high-grade tumors (30% vs. 16%, p = 0.01). There was a direct positive association with an increasing ODX score and HOMA-IR (p = 0.014). On subset analysis, this relationship was seen in White women (p = 0.005), but not in Black women (p = 0.55).

CONCLUSION

In women with newly diagnosed breast cancer, increasing insulin resistance is associated with a higher recurrence score; however, this association was not present in Black women. This lack of association may be due to the small number of Black women in the cohort, or possibly a reflection of a different biological disease process of the patient's tumor.

Impact of molecular subtypes on metastatic behavior and overall survival in patients with metastatic breast cancer: A single-center study combined with a large cohort study based on the Surveillance, Epidemiology and End Results database

Breast cancer is a highly heterogeneous disease at the molecular level and >90% of mortalities are due to metastasis and its associated complications. The present study determined the impact of molecular subtypes on metastatic behavior and overall survival (OS) of patients with metastatic breast cancer. The influence of molecular subtypes on the sites and number of metastases in 166 patients with metastatic breast cancer from a single center were assessed; and the influence of molecular subtypes on the sites and number of metastases and OS in 15,322 metastatic cases among 329,770 patients with primary breast cancer from the Surveillance, Epidemiology and End Results database were assessed. Analysis of both datasets revealed that different molecular subtypes exhibited differences in the prevalence of different metastatic sites and number of metastases. A larger proportion of bone metastasis was observed in the hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)+ subtype than in other subtypes, more lung metastasis was observed in the HR-/HER2+ subtype and more liver metastasis occurred in the HR+/HER2+ and HR-/HER2+ subtypes. Single-site metastasis was more common for the HR+/HER2- subtype than in other subtypes, while 2-3 sites of metastases were more common for the HR+/HER2+ subtype and ≥4 sites of metastases were more frequent in the HR-/HER2+ and HR-/HER2- subtypes. The mean OS of patients with primary breast cancer in the HR+/HER2- subtype group was the longest (78.5 months), while the HR-/HER2- group had the shortest mean OS (69.1 months). The mean OS of the metastatic HR+/HER2+ group was the longest (46.0 months), while the mean OS of the metastatic HR-/HER2- group was the shortest (18.5 months). In conclusion, the results of the present study suggested that different molecular subtypes of breast cancer have different metastatic behavior, as well as mean OS.