So if i’m reading this study correctly, then Swedish researchers found through DNA sequencing of tumors, etc that breast cancer metastases are NOT spread from the axillary lymph nodes.

“In the new study, the researchers have looked at the DNA in cancer tissue from 20 patients with  and metastases in both their axillary lymph nodes and other organs. By means of a technique called next-generation sequencing they were able to map the relationship between the cancer cells in the breast and those in metastases in other organs. This enabled them to show the cancer’s spread routes.

The study showed that tumour cells are spread from the breast tumour to the axillary lymph nodes and to other organs such as the skeleton and the brain. Metastases then often spread from the first organ to other organs in the next stage.

Our most important finding, however, was that the metastases in the axillary lymph nodes do not seem to spread further to other organs, so even if these metastases can show how aggressive the cancer is, it is not they that cause the spread,” says Johan Hartman, Associate Professor at Karolinska Institutet’s Department of Oncology-Pathology and one of the researchers who led the study.”

Wow, that’s actually big news with huge impact on treatment and care if its true. I don’t think I ever even questioned the spread route of breast tumor — lymph nodes– organs. This would explain why some women who have (like me) micrometastases in only one or two lymph nodes that are removed surgically then go on to have organ metastases. it would also explain the opposite– when women with multiple large lymph node metastases are spared organ metastases.

I wonder if oncologists/surgeons will change their recommendations over this……

I can’t help thinking about the history of mastectomy I first encountered in Emperor of All Maladies that described the amount of tissue that used to be removed in the good old Halsted days. I am grateful everyday for a) anesthesia and b) I don’t live in the good old Halsted days.