Triple negative breast cancer accounts for around 15% of breast cancers, and it is a more diagnosis common in younger women. This subtype of breast cancer tends to share similarities with BRCA-related disease, being more likely to be linked to faulty DNA repair and reprogrammed cellular metabolism. TNBC tumours don’t exhibit the over-expression of oestrogen and growth receptors found in other forms of breast cancer, and this lack of modifiable receptors tends to be seen as bad news. But all it really means is that we don’t currently have any specific adjuvant medical treatments, which makes it all the more important to look for other modifiable factors, such as diet and lifestyle.
In essence, triple negative breast cancer is a catch-all description for tumours that have no medically treatable receptors. In fact the TNBC label is a convenient description for a group of around six underlying breast cancer subtypes which tend to have widely varying cell mutations and behaviour. Just as there are no definitive treatments, there are no proven nutrition and lifestyle approaches, but researchers have identified several promising therapeutic targets and we can implement nutrition support that target the same areas.
The prevalence of triple negative cancers in younger women has prompted researchers to look at this group more closely to find modifiable diet and lifestyle factors. The negative factors are: positive energy balance (i.e. eating too many calories), overweight, and physical inactivity, Vitamin D deficiency, insulin resistance and inflammation. Positive factors that may improve disease outcomes include physical activity, sleep, Vitamin D adequacy (most people in UK are deficient), phytoestrogens, NSAIDs and aspirin (the effects of which can be simulated/augmented naturally by improving phytonutrient intake and omega balance). Alcohol intake is associated with a greater risk of recurrence. Women who implement and follow lifestyle modification after treatment tend to experience better results (Brenner, Brockton et al, 2016).
Like most cancers, TNBC tumour cells have reprogrammed metabolism that allows them to grow faster than healthy cells: they tend to have higher levels of glycolysis and thus use more glucose than other cancer types, but they can also use glutamine, an amino acid, to make energy via fermentation. TNBC cells are also capable of making their own fatty acids for structural or energy use via an enzyme called FASN. This makes it important to follow a carefully designed diet to manage these different factors. Interestingly, oestrogen is known to stimulate FASN expression so there may be a role for hormonal control in TNBC too (Long, Li, Zhang, 2016).
Nutrient density is important for all anti-cancer diets and especially so for TNBC. The potential for anti-cancer phytonutrients (plant chemicals) to inhibit cell invasion and migration has been demonstrated extensively in laboratory studies and animal experiments. There are also a handful of impressive case studies showing complete remission of triple negative breast cancer using an integrated approach (combined conventional and complementary protocols) published by Dr Ralf Kleef in Vienna and Dr Mehmet Ihikesici in Istanbul.
We still have a lot to learn about triple negative breast cancer and (as ever) our understanding of this area is limited by the lack of human studies, but the indications are that diet and lifestyle may be highly valuable in improving outcomes.
Brenner DR, Brockton NT, Kotsopoulos J, (2016) Breast cancer survival among young women: a review of the role of modifiable lifestyle factors. Cancer Causes Control; 27:459–72.
Jing-Pei Long, Xiao-Na Li, Feng Zhang, (2016) Targeting Metabolism in Breast Cancer: How far can we go? World J Clin Oncol. 2016 Feb 10; 7(1): 122–130.