Breast cancer recurrence following active treatment: determining its incidence in the NSW population

Long term risk of distant metastasis in women with non-metastatic breast cancer and survival after metastasis detection: a population-based linked health records study

OBJECTIVES

To estimate the long term risk of distant metastases (DM) for women with initial diagnoses of non-metastatic breast cancer; to estimate breast cancer-specific and overall survival for women with DM.

DESIGN

Population-based health record linkage study.

SETTING, PARTICIPANTS

Women diagnosed with localised or regional primary breast cancer recorded in the NSW Cancer Registry, 2001-2002.

MAJOR OUTCOME MEASURES

Time from breast cancer diagnosis to first DM, time from first DM to death from breast cancer.

SECONDARY OUTCOME

time to death from any cause.

RESULTS

6338 women were diagnosed with non-metastatic breast cancer (localised, 3885; regional, 2453; median age, 59 years [IQR, 49-69 years]). DM were recorded (to 30 September 2016) for 1432 women (23%; median age, 62 years [IQR, 51-73 years]). The 14-year cumulative DM incidence was 22.2% (95% CI, 21.1-23.2%; localised disease: 14.3% [95% CI, 13.2-15.4%]; regional disease: 34.7% [95% CI, 32.8-36.6%]). Annual hazard of DM was highest during the second year after breast cancer diagnosis (localised disease: 2.8%; 95% CI, 2.3-3.3%; regional disease: 9.1%; 95% CI, 7.8-10.3%); from year five it was about 1% for those with localised disease, from year seven about 2% for women with regional disease at diagnosis. Five years after diagnosis, the 5-year conditional probability of DM was 4.4% (95% CI, 3.7-5.1%) for women with localised and 10.4% (95% CI, 9.1-12.0%) for those with regional disease at diagnosis. Median breast cancer-specific survival from first DM record date was 28 months (95% CI, 25-31 months); the annual hazard of breast cancer death after the first DM record declined from 36% (95% CI, 33-40%) during the first year to 14% (95% CI, 11-18%) during the fourth year since detection.

CONCLUSIONS

DM risk declines with time from diagnosis of non-metastatic breast cancer, and the annual risk of dying from breast cancer declines with time from initial DM detection. These findings can be used to inform patients at follow-up about changes in risk over time since diagnosis and for planning health services.

Moving beyond the stage: how characteristics at diagnosis dictate treatment and treatment-related quality of life year losses for women with early stage invasive breast cancer

Background:Although evaluations of breast cancer screening programs frequently estimate quality-adjusted life-year (QALY) losses by stage, other breast cancer characteristics influence treatment and vary by mode of detection - i.e. whether the cancer is detected through screening (screen-detected), between screening rounds (interval-detected) or outside screening (community-detected). Here, we estimate the association between early-stage invasive breast cancer (ESIBC) characteristics and treatment-related QALY losses.Methods:Using clinicopathological and treatment information from 675 women managed for ESIBC, we estimated the average five-year treatment-related QALY loss by detection group. We then used regression analysis to estimate the extent to which known cancer characteristics and the detection mode, are associated with treatment and treatment-related QALY losses.Results:Community-detected cancers had the largest QALY loss (0.76 QALYs [95% CI 0.73;0.80]), followed by interval-detected cancers (0.75 QALYs [95% CI 0.68;0.82]) and screen-detected cancers (0.69 QALYs [95%CI 0.67;0.71]). Adverse prognostic factors more common in community-detected and interval-detected breast cancers (large tumours, lymph node involvement, high grade) were largely associated with QALY losses from mastectomies and chemotherapy. Receptor-positive subtypes, more common in screen-detected cancers, were associated with QALY losses related to endocrine therapy.Conclusions:The associations between ESIBC characteristics and treatment-related QALY losses should be considered when evaluating breast cancer screening and treatment strategies.

G0S2 represses PI3K/mTOR signaling and increases sensitivity to PI3K/mTOR pathway inhibitors in breast cancer

G0/G1 switch gene 2 (G0S2) is a direct retinoic acid target implicated in cancer biology and therapy based on frequent methylation-mediated silencing in diverse solid tumors. We recently reported that low G0S2 expression in breast cancer, particularly estrogen receptor-positive (ER+) breast cancer, correlates with increased rates of recurrence, indicating that G0S2 plays a role in breast cancer progression. However, the function(s) and mechanism(s) of G0S2 tumor suppression remain unclear. In order to determine potential mechanisms of G0S2 anti-oncogenic activity, we performed genome-wide expression analysis that revealed an enrichment of gene signatures related to PI3K/mTOR pathway activation in G0S2 null cells as compared to G0S2 wild-type cells. G0S2 null cells also exhibited a dramatic decreased sensitivity to PI3K/mTOR pathway inhibitors. Conversely, restoring G0S2 expression in human ER+ breast cancer cells decreased basal mTOR signaling and sensitized the cells to pharmacologic mTOR pathway inhibitors. Notably, we provide evidence here that the increase in recurrence seen with low G0S2 expression is especially prominent in patients who have undergone antiestrogen therapy. Further, ER+ breast cancer cells with restored G0S2 expression had a relative increased sensitivity to tamoxifen. These findings reveal that in breast cancer G0S2 functions as a tumor suppressor in part by repressing PI3K/mTOR activity, and that G0S2 enhances therapeutic responses to PI3K/mTOR inhibitors. Recent studies implicate hyperactivation of PI3K/mTOR signaling as promoting resistance to antiestrogen therapies in ER+ breast cancer. Our data establishes G0S2 as opposing this form of antiestrogen resistance. This promotes further investigation of the role of G0S2 as an antineoplastic breast cancer target and a biomarker for recurrence and therapy response.

Supportive care of women with breast cancer: key concerns and practical solutions

Patients diagnosed with breast cancer may have supportive care needs for many years after diagnosis. High quality multidisciplinary care can help address these needs and reduce the physical and psychological effects of breast cancer and its treatment. Ovarian suppression and extended endocrine therapy benefits are associated with vasomotor, musculoskeletal, sexual and bone density-related side effects. Aromatase inhibitor musculoskeletal syndrome is a common reason for treatment discontinuation. Treatment strategies include education, exercise, simple analgesia and a change to tamoxifen or another aromatase inhibitor. Chemotherapy-induced alopecia may be a constant reminder of breast cancer to the patient, family, friends, acquaintances and even strangers. Alopecia can be prevented in some patients using scalp-cooling technology applied at the time of chemotherapy infusion. The adverse impact of breast cancer diagnosis and treatment on sexual wellbeing is under-reported. Identification of physical and psychological impacts is needed for implementation of treatment strategies. Fear of cancer recurrence reduces quality of life and increases distress, with subsequent impact on role functioning. Identification and multidisciplinary management are key, with referral to psychosocial services recommended where indicated. The benefits of exercise include reduced fatigue, better mental health and reduced musculoskeletal symptoms, and may also include reduced incidence of breast cancer recurrence. Identification and management of unmet supportive care needs are key aspects of breast cancer care, to maximise quality of life and minimise breast cancer recurrence.