Chemotherapy: before or after surgery?

Surgical oncologist Professor Andrew Spillane explains why some people have neoadjuvant chemotherapy – chemotherapy before surgery.

Traditionally, neoadjuvant chemotherapy (NACT) has been used for inoperable and inflammatory breast cancer. However, increasingly NACT is being used in patients with earlier operable breast cancer.

When breast cancer is first diagnosed, it is often already clear that chemotherapy will need to be part of the person’s treatment, even without the full results of surgery. Factors that may influence this include the person’s age, the grade and subtype of the tumour, the tumour size, and whether the cancer has spread to lymph nodes. For example, younger women with high grade, non-hormonal breast cancers inevitably benefit from chemotherapy, even when the tumour is quite small.

Clinical trials comparing NACT with chemotherapy after surgery showed they were equal in terms of survival. The advantage of NACT is that it helps reduce the extent of surgery. Even if the tumour is suitable for breast conserving surgery, if it becomes smaller with NACT this reduces the amount of breast tissue that needs to be removed and results in better cosmetic outcomes (see article about radiotherapy and reconstruction here).

NACT also reduces the chance of having cancer cells in the lymph node at the time of surgery. This is beneficial, as lymph node removal increases the risk of developing lymphoedema.

When surgery is done first, we can see exactly how big the tumour was before treatment and whether the lymph nodes were involved. These factors give a guide to the prognosis and help to determine the need for chemotherapy. With NACT, the decision about chemotherapy is already made, and the surgery shows how the person’s tumour responded to chemotherapy.

However, NACT isn’t effective for all tumours, especially the subtype of breast cancer called Luminal A tumours that are low-grade and strongly oestrogen and progesterone receptor positive.

Clinical trials are now assessing the benefits of giving new drugs before surgery. For people with less sensitive subtypes of breast cancer or tumours that don’t respond well to standard drug combinations, these clinical trials can identify treatments that are likely to be superior. These trials can lead to faster introduction of new drugs into standard care than much larger post-surgery trials that take years to give results.

NACT is an important option that health professionals should be talking to their patients about if they believe chemotherapy will definitely be part of the treatment recommendation at the time of the first diagnosis of breast cancer.

Issue 83
Spring 2018