Can neoadjuvant therapy influence other treatments for breast cancer?

This study aimed to investigate whether neoadjuvant systemic therapy (NST) influenced the eligibility of HER2 positive breast cancer patients to undergo breast conserving therapy (BCT).

This study concluded the use of NST can result in patients who are non-eligible for BCT converting to patients that are eligible for BCT. 

Neoadjuvant systemic therapy (NST) involves giving treatments, such as chemotherapy or targeted therapies, to patients before surgery in an attempt to reduce the size or extent of the cancer.

Breast conserving therapy (BCT) is a less extreme surgery than a mastectomy which involves removal of the breast. In BCT part of the breast tissue is removed rather than the entire breast. BCT is more likely to be carried out in patients who have NST rather than a surgery as their first treatment option.

It was unknown what percentage of patients converted from non-BCT eligible to BCT-eligible when treated with NST. 

This study involved 292 HER2 positive breast cancer patients. Patients were assessed before and after NST to class them as BCT-ineligible or BCT-eligible.

Of the 292 patients, 59% were non-BCT eligible before NST. Of this group, 43% converted to BCT-eligible when treated with NST. 67% of these patients opted for BCT as treatment while 23% chose a mastectomy.

The BCT eligibility rate increased from 41% to 64% after NST treatment.

A pathologic complete response (PCR) indicates that the treatment was completely successful. The PCR was 55% for patients BCT eligible before and after NST. The PCR was 44% for patients who were BCT ineligible before NST regardless of conversion to BCT eligible or not. 

This study concluded that many patients who are BCT ineligible can be converted to BCT eligible with NST treatment. It was also concluded that patients who were BCT eligible before NST have a higher PCR than those who were BCT ineligible before NST. 

Consult your physician about NST as a treatment and your BCT eligibility.