Pembrolizumab and Chemotherapy Treatment or no Treatment Guided by the Level of TILs in Resected Early-stage TNBC

This research is looking into how we treat a specific type of breast cancer called triple-negative breast cancer (TNBC). This type of cancer tends to affect younger women and can be more aggressive than other types. Currently, most people with early-stage TNBC have surgery, often followed by chemotherapy and sometimes radiotherapy. While chemotherapy is very effective, it can also have long-lasting side effects that affect a person's quality of life.

Doctors have noticed that some patients with early-stage TNBC, especially those with small tumours and no spread to lymph nodes, seem to do very well, even without extensive chemotherapy. This study focuses on a key factor: 'tumour-infiltrating lymphocytes' (TILs). These are immune cells that have entered the tumour, suggesting the body's immune system is already trying to fight the cancer. The idea is that if a tumour has many TILs, it might not need as much chemotherapy, or perhaps none at all.

The ETNA study is designed to explore this idea. It aims to find out if it's safe and effective to reduce or even skip chemotherapy for certain patients with early-stage TNBC who have high levels of TILs. The study will divide patients into different groups based on their TIL levels and age. Some groups might receive a combination of Pembrolizumab (a new type of immune-boosting drug) and Paclitaxel (a chemotherapy drug), while others with very high TILs might just be monitored closely without any active cancer treatment, to see if they still achieve excellent outcomes. This could help tailor treatments more precisely, potentially reducing side effects for many patients.