Using best-practices in triple negative breast cancer treatment; do deviations matter?

This paper studied how patients with triple negative breast cancer adhere to treatment guidelines, and whether this is associated to survival rates.

Triple negative breast cancer refers to cancers with the absence of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2).  It is associated with a poorer disease outcome compared to other subtypes of breast cancer, as cancers with these receptors present can be treated with specific drugs.

Currently, there is little evidence of the impact of age on survival among patients with triple negative breast cancer. It is also important to understand the link between receiving treatment as outlined by international best-practices (guideline-adherent) and survival. 

9,156 patients with breast cancer were analyzed. Information on the treatment received, type of breast cancer and characteristics of tumour were collected. The adherence of patients to evidence-based treatments (making treatment decisions based on the best evidence available) were studied.

Of the 9,156 patients, 9.2% had triple negative breast cancer. Triple negative breast cancer patients had a significant decrease in overall survival and disease free survival compared to patients without triple negative breast cancer.

Patients with triple negative breast cancer had lower adherence to treatment guidelines compared to patients without triple negative breast cancer. This was mostly due to either omitting or abandoning chemotherapy treatment.

In all age groups, patients with triple negative breast cancer who were treated according to guidelines had a better overall survival (percentage of people who are still alive) and a better disease free-survival (time without symptoms of cancer). This was more significant in younger and older patients. Patients aged 65 and above who were not treated according to guidelines had a 2.89 times reduced overall survival and a 2.72 times reduced disease-free survival. Patients younger than 50 years who were not treated according to guidelines had a 3.47 times overall survival and a 3.2 times reduced disease free survival.

Among triple negative breast cancer patients who adhered to guidelines, there was no significant differences in overall survival and disease free survival across the different age groups.

The authors concluded that adherence to treatment guidelines improved the survival of  triple negative breast cancer patients, especially those who were younger than 50 and older than 65 years. 

Comorbidities (presence of additional diseases) might affect guideline adherence and disease outcome.  

While each patient is different, and therefore your treatment will be specific to your breast cancer, ask your doctor about the international best-practices when it comes to treatment of triple negative breast cancer.