Sentinel Lymph Node Detection After Neoadjuvant Chemotherapy for Large Operable Breast Cancer (GANEA2)

Evaluation of Sentinel Lymph Node Detection After Neoadjuvant Chemotherapy for Large Operable Breast Cancer

Neoadjuvant chemotherapy (NAC) is frequently proposed to patients with large tumours that can be operated in order to increase the chances of breast conservation. After NAC, patients are operated with systematic axillary lymph node dissection (ALND), although more than half of these patients do not have lymph node involvement. These results lead us to consider the indication of the sentinel lymph node (SLN) technique after NAC in order to avoid unnecessary ALND in patients whose SLN is free of involvement. We need to validate the SLN technique after NAC in patients who have proven lymph node involvement prior to NAC. GANEA2 is a new trial based on patient treated for a large breast tumor with proven axillary involved nodes. Patients enrolled in this trial will have first an axillary sonography with fine needle punction in case of suspected nodes before NAC. This primary evaluation allow to determine two groups of patients : group 1 (pN+) : patients with proven involved axillary nodes and group 2, patients without proven axillary involved nodes (cN0). Patients of group 1, will undergo SLNB and complete level I-II axillary lymphadenectomy. Patients of group 2 will undergo SLNB and a complete axillary level I-II lymphadenectomy only in the case of detection failure or involved SLN and a SLNB alone in the others cases. Patients of this last group will be followed 5 years in order to evaluate the risk of axillary relapse without lymphadenectomy.

Breast cancer, neoadjuvant chemotherapy, False negative rate, Axillary lymph node dissection, Sentinel lymph node

Early breast cancer patients treated with neo-adjuvant chemotherapy (NAC) were included. Before NAC, patients with cytologically proven node involvement were allocated into the pN1 group, other patient were allocated into the cN0 group. After NAC, pN1 group patients underwent sentinel lymph node (SLN) and axillary lymph node dissection (ALND); cN0 group patients underwent SLN and ALND only in case of mapping failure or SLN involvement.

Patients without proven axillary involved nodes will undergo SLN biopsy and a complete axillary level I-II lymphadenectomy only in the case of detection failure or involved SLN and a SLN biopsy alone in the others cases. Patients of this last group will be followed 5 years in order to evaluate the risk of axillary relapse without lymphadenectomy.

group 1 : patients with proven involved axillary nodes will undergo SLN biopsy and complete level I-II axillary lymphadenectomy.

Group 2 : Patients without proven axillary involved nodes will undergo SLNB and a complete axillary level I-II lymphadenectomy only in the case of detection failure or involved SLN and a SLNB alone in the others cases. Patients of this last group will be followed 5 years in order to evaluate the risk of axillary relapse without lymphadenectomy.

group 1 : patients with proven involved axillary nodes will undergo SLNB and complete level I-II axillary lymphadenectomy.

Ratio of the number of FN cases to the total number of patients with at least one lymph node involved, sentinel or not. a FN case was defined as a patient with a successful mapping, SLN(s) without any metastasis, and a metastasis in at least one node from the ALND

The Sataloff classification assesses the response of the NAC on the breast tissue. TA: total or almost total therapeutic effect. TB: therapeutic effect > 50%. TC: < 50% therapeutic effect but obvious effect. TD: no therapeutic effect

The Sataloff classification assesses the response of the NAC on the lymph nodes NA: clear therapeutic effect, no metastases. NB: no therapeutic effect, no metastases. NC: aspects of therapeutic effect, but presence of metastases. ND: no therapeutic effect, viable metastases.

Inclusion Criteria: T2-T3 operable infiltrating breast carcinoma No allergy to Patent Blue Pre-operative diagnosis of unifocal infiltrating breast carcinoma. Patient planned to be treated by NAC. Informed consent. Surgery available 4 to 6 weeks after the last chemotherapy course (radical or conservative surgery) Exclusion Criteria: pT4d (inflammatory breast cancer) Locally advanced or metastatic breast cancer Any previous chemotherapy of contra-lateral breast cancer. Breast cancer local relapse Previous surgical removal of breast Cancer. Inadequate biopsy for pathological analysis. Dementia or altered mental disorder Pregnant woman or breast feeding or without efficacious contraceptive method. Contra-indication to NAC NAC interrupted due to progressive disease. Neoadjuvant radiotherapy.