Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy.

Importance: Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown. Objective: To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node. Design, Setting, and Participants: In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis. Exposure: Omission of ALND after SLNB or TAD. Main Outcomes and Measures: The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed. Results: A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55). Conclusions and Relevance: The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

Avaliaçäo da resposta do câncer de mama localmente avançado em pacientes submetidas à quimioterapia neoadjuvante / Evaluation of te response of locally advanced breast cancer in patients submitted to neoadjuvant chemotherapy

Este trabalho tem como objetivo avaliar a resposta do câncer de mama, estádio III, em pacientes submetidas à quimioterapia neoadjuvante, estudar os fatores relacionados à resposta e verificar a acurácia do exame físico como método de avaliaçäo da resposta do tumor à quimioterapia. Em um período de 6 anos, 71 pacientes com carcinoma de mama, E III, foram submetidas à quimioterapia neoadjuvante com o esquema FACV (ciclofosfamida 400 mg/m2, 5-fluorouracil 400 mg/m, doxorrubicina 10 mg/m2 e vincristina 1 mg/m2). Foram realizados 6 ciclos semanais antes da cirurgia e 11 ciclos quinzenais, após o tratamento cirúrgico. Na avaliaçäo clínica após o 6§ ciclo, houve reduçao completa do tumor em 9 por cento dos casos; reduçäo maior que 50 por cento em 59 por cento das pacientes e, em 32 por cento dos casos houve reduçäo menor que 50 por cento ou progressäo. Apenas o tamanho do tumor inicial esteve significativamente associado à resposta tumoral, sendo que tumores maiores mostraram-se mais responsivos. Dentre os 57 casos apontados como tendo tumor residual ao exame físico, 52 foram confirmados histologicamente. Dos 6 casos sem tumor ao exame físico, dois foram confirmados histologicamente. A acurácia total do exame clínico foi de 86 por cento, a sensibilidade de 93 por cento, a especificidade de 29 por cento, o valor preditivo positivo de 91 por cento e o valor preditivo negativo de 33 por cento. Concluiu-se que a quimioterapia neoadjuvante proporcionou boa reduçäo dos tumores, sendo que os maiores apresentaram uma melhor resposta. O exame físico apresenta baixa acurácia no estudo da resposta tumoral e, isoladamente, näo é um bom método de avaliaçäo.