Cancer in post-menopausal women; determining outlook

The authors aimed to assess the prognostic (treatment outlook) factors associated with breast cancer in post-menopausal women with specific tumor characteristics.

Lymph nodes are tiny bean shaped organs and are often the first site to which cancer will spread. This is known as lymph node involvement.

Adjuvant endocrine therapy (hormone therapy given after surgery to lower the risk of the cancer returning) is often given to patients with node-positive breast cancer who are hormone receptor positive (hormone receptors including estrogen receptor [ER] and/or progesterone receptor [PR] present on cancer cells).

While the outlook of patients with node-positive breast cancer is can be less favorable that for those with node-negative cancer, distinct prognostic factors involving specific lymph node characteristics have not been well explained.

The aim of this study was to evaluate the prognosis of postmenopausal patients with early breast cancer. 

A total of 2,197 patients were evaluated for a disease prognosis. Patients were split into three groups based on low-, intermediate- and high-risk of cancer recurring based on an evaluation of 58 genes. Patients were then further divided based on the number of lymph nodes present and the ten year risk of cancer returning was evaluated. All patients were taking some form of hormone therapy. 

In those patients deemed to be low-risk by the genetic score, those with no positive lymph nodes had a 5% risk of cancer returning within 10 years, compared to 7% for those with 1 positive lymph node. In those patients deemed to be intermediate-risk by the genetic score, those with no positive lymph nodes had a 15% risk of cancer returning within 10 years, compared to 15.5% for those with 1 positive lymph node. Due to the small number of low-and intermediate-risk patients with 2 – 3 positive lymph nodes, these two groups were put together and the risk of cancer returning within 10 years was estimated to be 12.5%.

In those patients deemed to be high-risk by the genetic score, those with no positive lymph nodes had 20% risk of cancer returning within 10 years compared to 26% for those with 1 positive lymph node and 34% for those with 2 – 3 positive lymph nodes. 

Patients were also split into groups based on whether they had luminal A (positive for ER and PR but negative for the HER2 protein) or luminal B cancer (positive for ER and HER2 but negative for PR). In general, regardless of how many lymph nodes were involved, those with luminal B cancer were more at risk of cancer returning within 10 years, including a 40% risk of cancer returning in those with luminal B cancer and 2 -3 positive lymph nodes. 

The authors concluded that lymph node involvement in breast cancer in post-menopausal women negatively affected prognosis by increasing the risk of cancer recurrence.