A. Johansson (Stockholm, Sweden)
Author Of 1 Presentation
15P - The combined influence of receptor subtype, grade and TN status on breast cancer survival in recently treated women with non-metastatic disease in Norway
Abstract
Background
Receptor subtypes of breast cancer, as defined by immunohistochemistry, are surrogates for molecular subtypes. Despite new emerging molecular tumour classifications, these receptor subtypes are well-known independent predictors of breast cancer death and remain widely used in clinics. Few studies have disentangled the combined influence of receptor subtypes, grade, size (T) and nodal status (N) on breast cancer survival in large groups of recently treated patients.
Methods
From the Cancer Registry of Norway, we obtained detailed clinical information on 24137 women with invasive breast cancer aged 20 to 74 between 2005 and 2015. Of these, 17204 had non-metastatic breast cancer with known receptor status. Receptor subtype was defined by estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status. Hazard ratios for breast cancer death up to 13 years after diagnosis were estimated using flexible parametric survival models and comparing combinations of receptor subtype, grade and TN status with adjustments for age, year and surgery type. Additional adjustment for adjuvant treatment was done on a subset of women with known treatment information.
Results
Receptor subtype, grade and TN status were strong predictors for breast cancer death, both independently and in combination. The combined effect of all factors was a 20- to 40-fold higher breast cancer mortality rate when comparing to women with the best outcome (ER+PR+HER2-, low grade, T1N0). In women with ER+HER2- subtypes and no nodal spread, a larger tumour size was associated with a significantly higher risk of breast cancer death. Women with ER+HER2- tumours also had an increased late (>5 years) mortality which was largely explained by intermediate/high grade and nodal spread. Women with ER+PR-HER2-, high grade, N+ tumours had particularly high mortality similar to triple negative breast cancer.
Conclusions
These results highlight the importance of thoroughly combining well-known tumour factors to describe the wide range of risks of dying from breast cancer, also among small, node negative tumours.
Legal entity responsible for the study
Cancer Registry of Norway.
Funding
Norwegian Cancer Society under Grant 161326.
Disclosure
All authors have declared no conflicts of interest.
Presenter Of 1 Presentation
15P - The combined influence of receptor subtype, grade and TN status on breast cancer survival in recently treated women with non-metastatic disease in Norway
Abstract
Background
Receptor subtypes of breast cancer, as defined by immunohistochemistry, are surrogates for molecular subtypes. Despite new emerging molecular tumour classifications, these receptor subtypes are well-known independent predictors of breast cancer death and remain widely used in clinics. Few studies have disentangled the combined influence of receptor subtypes, grade, size (T) and nodal status (N) on breast cancer survival in large groups of recently treated patients.
Methods
From the Cancer Registry of Norway, we obtained detailed clinical information on 24137 women with invasive breast cancer aged 20 to 74 between 2005 and 2015. Of these, 17204 had non-metastatic breast cancer with known receptor status. Receptor subtype was defined by estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status. Hazard ratios for breast cancer death up to 13 years after diagnosis were estimated using flexible parametric survival models and comparing combinations of receptor subtype, grade and TN status with adjustments for age, year and surgery type. Additional adjustment for adjuvant treatment was done on a subset of women with known treatment information.
Results
Receptor subtype, grade and TN status were strong predictors for breast cancer death, both independently and in combination. The combined effect of all factors was a 20- to 40-fold higher breast cancer mortality rate when comparing to women with the best outcome (ER+PR+HER2-, low grade, T1N0). In women with ER+HER2- subtypes and no nodal spread, a larger tumour size was associated with a significantly higher risk of breast cancer death. Women with ER+HER2- tumours also had an increased late (>5 years) mortality which was largely explained by intermediate/high grade and nodal spread. Women with ER+PR-HER2-, high grade, N+ tumours had particularly high mortality similar to triple negative breast cancer.
Conclusions
These results highlight the importance of thoroughly combining well-known tumour factors to describe the wide range of risks of dying from breast cancer, also among small, node negative tumours.
Legal entity responsible for the study
Cancer Registry of Norway.
Funding
Norwegian Cancer Society under Grant 161326.
Disclosure
All authors have declared no conflicts of interest.