The Long View
Intratumoral heterogeneity of the ER appears to double risk of fatal breast cancer for up to 25 years
A recent study suggests that the estrogen-receptor (ER)-positive subset of breast cancer may have deeper ramifications than previously suspected (1). “Women who develop ER-positive breast cancer have a remaining long-term risk of fatal disease for more than 20 years,” says study author Linda Lindström, Assistant Professor and Group Leader in the Department of Biosciences and Nutrition at the Karolinska Institutet, Sweden. “We and other researchers have shown that the ER can change when a breast cancer tumor spreads, which affects survival – patients with high intratumoral heterogeneity of the ER were twice as likely to die up to 25 years after diagnosis as patients with low heterogeneity.”
The clinical trial includes patients with low-risk, node-negative, ER-positive breast cancer and is independent of other known tumor markers. Lindström adds, “Patients with luminal A breast cancer and high intratumoral heterogeneity of the ER were also twice as likely to die of their disease.” This finding could help to identify patients at a high long-term risk within the luminal A breast cancer subtype for which patients usually have a good prognosis. Though there is currently no definitive explanation of the underlying mechanisms, the researchers suggest that, given that ER-positive disease is associated with an increased long-term risk of fatal disease, having dormant tumor cells with varying tumor characteristics, as compared with more homogeneous characteristics, may be beneficial for tumor progression and influence patient survival.
If validated, the researchers believe their findings could become actionable in the near future. Lindström says, “We are currently conducting several studies to further understand the long-term risk of fatal breast cancer as determined by patient and tumor characteristics, and we’re also continuing our studies on intratumoral heterogeneity in breast cancer.”
- LS Lindström et al., “Intratumor heterogeneity of the estrogen receptor and the long-term risk of fatal breast cancer”, J Natl Cancer Inst, [Epub ahead of print] (2018). PMID: 29361175.
My fascination with science, gaming, and writing led to my studying biology at university, while simultaneously working as an online games journalist. After university, I travelled across Europe, working on a novel and developing a game, before finding my way to Texere. As Associate Editor, I’m evolving my loves of science and writing, while continuing to pursue my passion for gaming and creative writing in a personal capacity.