Breast cancer, one of the most prevalent malignant tumors among women, poses a significant threat to their health. Surgery is an essential localized treatment for these patients, and dealing with axillary lymph nodes, breast conservation, and reconstruction are crucial components in transitioning to individualized treatment. At the 18th St. Gallen International Breast Cancer Conference (SGBCC 2023), Oncology Frontier approached Dr. Monica Morrow of the Memorial Sloan Kettering Cancer Center (MSKCC) to discuss axillary treatment, breast conservation, and reconstruction, inviting her to share her clinical experiences and views.
Oncology Frontier：What kinds of patients need cavity shaving margin (CSM)？
Dr. Monica Morrow：The Cavity Shave Margins (CSM) approach is generally used to lower the incidence of false-positive margins. When marking for lumpectomy, the dye can infiltrate small crevices, which might lead to false-positive outcomes. We apply CSM to all patients. The evident primary tumor is initially removed, then the tumor’s distinct margins are extracted, and new margin sites are marked. Only if tumors are present in the new margins do we classify them as positive.
Oncology Frontier：Is the extent of breast conservation after neoadjuvant therapy always assessed based on the post-treatment tumor size?
Dr. Monica Morrow：Concerning how much breast tissue to remove post-neoadjuvant chemotherapy, it’s unnecessary to excise the entire tumor bed. The very essence of neoadjuvant treatment lies in enabling the removal of a smaller amount of breast tissue.
Oncology Frontier: Are tattoos or marking clips indispensable for breast conservation post-neoadjuvant therapy?
Dr. Monica Morrow：The MRI is the most precise imaging technique following neoadjuvant treatment. If abnormalities appear in post-treatment MRI results, the initially placed breast localization clip must be extracted. If patients achieve complete clinical and radiological remission, then the localization clip and adjacent samples of tissue with a normal appearance are removed. A localization clip should be placed at each site of malignancy, especially when considering neoadjuvant treatment or when the tumor is small. Even after a complete excision of the primary tumor based on biopsy, placing a localization clip to mark the malignancy remains necessary.
Oncology Frontier :Do you agree with the pattern of the optimal combination of neoadjuvant chemotherapy, preoperative radiotherapy and deep inferior epigastric perforator (DIEP) flap reconstruction in the PRADA study?
Dr. Monica Morrow：The PRADA study and preoperative radiation results are notably intriguing. It’s evident that postoperative radiation can influence breast reconstruction outcomes. This research suggests that initial tumor treatments can be concluded, and commendable results achieved through reconstruction. Presently, our institution is duplicating this research in treatments for locally advanced breast cancer patients, aspiring to attain a comparably low incidence of complications as in the PRADA study.
Oncology Frontier : Is axillary lymph node dissection mandatory?
Dr. Monica Morrow：The question is expansive. In the debate surrounding axillary lymph node dissection, for patients showing residual sentinel lymph node lesions post-neoadjuvant chemotherapy, including micro-metastases, axillary lymph node dissection in conjunction with radiation is standard. The American Alliance trial and the European TAXIS trial offer some direction, aiming to determine if we can achieve a heightened rate of local lesion control without resorting to axillary lymph node dissection. However, results might diverge depending on the patient’s ER, PR, and HER2 status. Until forward-looking trial results emerge, axillary lymph node dissection coupled with radiation remains the standard practice.
Monica Morrow
Chief of Breast Surgery, Memorial Sloan Kettering Cancer Center
