Is it possible to avoid unnecessary axillary lymph node dissection (ALND) after neoadjuvant chemotherapy? This is the question researchers sought to answer through the GANEA 2 clinical trial.
Data from this study determined that patients with large, operable breast tumors and no clinical signs of the cancer in the axillary lymph nodes prior to neoadjuvant chemotherapy had a low risk for breast cancer recurrence in the axillary lymph nodes when a sentinel lymph node biopsy (SLNB) during surgery showed no signs of cancer (Abstract S2-07).
“Axillary lymph node dissection is often performed to check whether a patient's cancer has spread outside the breast after neoadjuvant chemotherapy,” said Jean-Marc Classe, MD, PhD, Head of Surgery at the Institut de Cancerologie de l'Ouest René Gauducheau in Nantes, France, in a statement. “ALND has a high risk for serious complications and long-term sequelae. So we wanted to assess the feasibility and safety of the less-invasive procedure of SLNB for patients treated with neoadjuvant chemotherapy for a large breast cancer.
“We found that for patients with no proof of cancer in the axillary lymph nodes before neoadjuvant chemotherapy, SLNB during the surgery after neoadjuvant chemotherapy was safe because those who had a negative SNLB and did not have an ALND had a very low risk of an axillary relapse at 3 years after surgery,” continued Classe, who is also Professor of Oncology at the Medical University in Nantes. “We had expected more axillary lymph node relapses than we observed, so this is very exciting and will hopefully mean that more patients are spared the potential complications of invasive ALND.”
GANEA 2 Methodology
From July 2010 to February 2014, researchers enrolled 590 patients in the trial who had large, operable breast tumors. The participants had no cancer in the lymph nodes, which was determined by axillary sonography with fine needle cytology. All of the patients in the trial underwent neoadjuvant chemotherapy followed by surgery and SLNB.
Patients with a proved axillary node involvement were allocated in group 1, and patients without any proved lymph node involvement were allocated in group 2, according to Classe.
Investigators found cancer cells in the SLNB samples of 139 patients; this group of patients then underwent ALND. No cancer cells were detected in 432 patients; among these patients, 416 were available for follow-up. The median follow-up for this group was 35.8 months.
Pathological analyses were carried out according to standard methods and classified according to the last American Joint Committee on Cancer staging system, researchers reported. Studies parameters included SLND detection rate, pathological results on breast specimen and nodes, rate of relapse, and survival.
At 3 years, disease-free survival for patients who did not receive ALND was 94.8 percent. Only one patient experienced axillary lymph node relapse, according to Classe. Additionally, there were nine other relapses: metastatic (n=3) or recurrences in the breasts (n=6). Overall survival was 98.7 percent.
In group 1, after neoadjuvant chemotherapy, the sentinel identification rate was 83.1 percent with a false-negative rate of 14.2 percent, reported Classe.
“This is the most important series of patients followed 2.3 years after SLND without auxiliary lymphadenectomy after neoadjuvant chemotherapy for an advanced breast cancer, showing acceptable results,” researchers concluded. “The current series validate the safety of this conservative strategy avoiding systematic lymphadenectomy to patients without initially involved axillary node treated with neoadjuvant chemotherapy.”
Classe noted that longer follow-up is needed to confirm the safety of SLNB for these patients.
Looking forward, Classe told Oncology Times, that “we must improve patient selection to avoid more unnecessary ALND for those patients with previous axillary involvement before neoadjuvant chemotherapy.”
“The disease-free and overall survival results we observed for the patients who underwent only an SLNB after neoadjuvant chemotherapy are comparable with the historical survival rates for patients in this situation who have ALND rather than SLNB,” Classe noted. “Therefore, an ALND could be avoided by patients who have no signs of cancer in the axillary lymph nodes following a sonographic axillary assessment prior to neoadjuvant chemotherapy and SLNB during surgery after neoadjuvant chemotherapy.”
Classe and colleagues are currently building a GANEA 3 trial to improve the “selection of patients who could avoid unnecessary ALND after neoadjuvant chemotherapy, even in the case of initially involved node before treatment.”
Catlin Nalley is associate editor.