Küemmel, Sherko

Abstract Background: In patients with micro- and macrometastases in the sentinel lymph node (SLN) after neoadjuvant chemotherapy (NAC), additional positive nodes are found in >60% of cases and axillary lymph node dissection (ALND) is currently considered standard of care. The likelihood of finding additional positive lymph nodes in patients with residual isolated tumor cells (ITCs) is unknown, and the benefit of ALND is unclear. As a consequence, surgical management of the axilla in these patients is not standardized. We sought to evaluate how often additional positive lymph nodes are found, to determine factors associated with ALND, and to compare oncological outcomes in patients treated with and without ALND after identification of residual ITCs in the SLN. Methods: Data were collected from 42 centers: 20 in the Oncoplastic Breast Consortium (OPBC) and EUBREAST networks, and 22 in North and South America. We included patients with cT1-4 N0-3 breast cancer at diagnosis who underwent NAC followed by axillary staging with either SLN biopsy (SLNB) or targeted axillary dissection (TAD) and were found to have residual ITCs [ypN0(i+)]. Single-tracer mapping was allowed for cN0 patients, while dual mapping or TAD was required for cN+ cases. Axillary treatment included completion ALND and/or nodal radiotherapy (RT). Competing risk analysis was performed to assess the cumulative incidence rates of any axillary recurrence (AR), locoregional recurrence (LRR), and any invasive (locoregional or distant) recurrence. Five-year cumulative incidence rates were compared between patients who underwent ALND and those who did not using the Gray’s test. Type I error rate was set to 0.05 (α). Results: We included 412 patients treated with NAC followed by surgery from 01/2009-05/2022. 146 (35.4%) had completion ALND and 266 (64.6%%) did not. Median patient age was 48 years. The majority (57%) of patients had clinical T2 tumors, and 68% had biopsy-proven N1 disease. Most were HR+/HER2- (41%) or HER2+ (39%). Most patients (80%) received anthracycline and taxane-based chemotherapy regimens. Nodal RT was administered to 83% of patients. The median number of SLNs with ITCs was 1. Patients treated with ALND were more likely to have ITCs detected on frozen section (61% v 6.7%, p< 0.001), to have N2/3 disease at presentation (15.1% v 5.6%, p=0.001) and to have LVI (40% v 26%, p=0.004) (Table 1). There was no significant trend over time in the proportion of patients undergoing completion ALND during the study period (p=0.5). In the ALND group, additional positive nodes were found in 43/146 (29.5%) of cases, and consisted of macrometastases in 11/146 (7.5%), micrometastases in 9/146 (6.2%), and ITCs in 23/146 (15.8%). 5-year rates of any AR, LRR, and any invasive recurrence in the entire cohort were 2.7% (95% CI 1.2-5.4), 2.8% (95% CI 1.2-5.4) and 16% (95% CI 11-21), respectively. There was no statistical difference between patients who underwent ALND and those who did not in any of the 3 endpoints (2.2% v 3.1%, p=0.6), (2.6% v 3.0%, p=0.4) and (14% v 18%, p=0.12), respectively. Conclusion: The likelihood of finding additional positive lymph nodes in patients with ITCs after NAC is lower than in patients with residual micro- and macrometastases, and in the majority of cases, they contain ITCs. Nodal recurrence after omission of ALND is rare in this population. Overall, these results do not support routine ALND in patients with residual ITCs. Table 1. Clinicopathological Features of the Study Cohort, Stratified by Type of Axillary Surgery Frequency (row percent) reported for categorical variables, and median (IQR) reported for continuous variables. SLNB sentinel lymph node biopsy; TAD targeted axillary dissection; SLNs sentinel lymph nodes; LNs lymph nodes; pCR pathologic complete response; ACT anthracycline and taxane; AC anthracycline; H Herceptin, HP, Herceptin and Perjeta; TC taxol (or Taxotere) and carboplatinum; LVI lymphovascular invasion; BCS breast-conserving surgery. ^ Applied to HER2- tumors only (n=252). ^^ Applies to HER2+ tumors only (n=160). # LVI was present on core biopsy or final pathology. * Applies to BCS patients only (n=175). ** Applies to mastectomy patients only (n=237). Citation Format: Giacomo Montagna, Alison Laws, Massimo Ferrucci, Mary Mrdutt, Natália Polidorio, Varadan Sevilimedu, Tracy-Ann Moo, Andrea Barrio, Marissa K. Boyle, Flavia Vidal Cabero, Daniela Cocco, Fabio Corsi, Angelena Crown, Meghan R. Flanagan, Mehmet Ali Gulcelik, Callie Hlavin, Justyna Jelinska, Hasan Karanlik, Susan Kesmodel, Henry Kuerer, Sherko Küemmel, Cornelia Leo, Tehillah Menes, Melissa Pilewskie, Nina Pislar, Nicola Rocco, Jai Min Ryu, Leonardo Soares, Christoph Tausch, M. Umit Ugurlu, CICERO URBAN, Astrid Botty van de Bruele, Denise Vorburger, Fredrik Wärnberg, Anna Weiss, Austin Williams, Stephanie Wong, Steven G. Woodward, Susie X. Sun, Jennifer Q. Zhang, M. Firdos Ziauddin, Guldeniz Karadeniz Cakmak, Nuran Bese, Thorsten Kühn, Judy Boughey, Tari King, Nina Ditsch, Maggie Banys-Paluchowski, Monica Morrow, Walter Weber. Are nodal ITCs after neoadjuvant chemotherapy an indication for axillary dissection? The OPBC05/EUBREAST-14R/ICARO study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr GS02-02.

ImportanceData 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.ObjectiveTo 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 ParticipantsIn 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.ExposureOmission of ALND after SLNB or TAD.Main Outcomes and MeasuresThe 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.ResultsA 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 RelevanceThe 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.

Abstract Background: The level of immune suppression in an individual breast cancer (BC) patient is relevant for having a major benefit from treatments that act via or are directed to the immune response, such as anti-HER2 agents and immune checkpoint molecules, respectively. The link(s) between the tumor immune microenvironment and treatment responses has been investigated in HER2-positive BC. This study analyzed the association between baseline expression of genes regulating T cell activities (PD1, CTLA4, LAG3, TIM3, PDL1, PDL2, FOXP3, IL10, TGFβ (1-3), FOXP1 and other related genes) and pathologic complete response (pCR) rates in the NeoALTTO trial. Methods: NeoALTTO randomized early-stage HER2-positive BC patients to neoadjuvant trastuzumab (T), lapatinib (L) or T+L for 6 weeks followed by 12 weeks of concurrent paclitaxel. Anthracyclines were given after surgery (FEC). Patients with RNA sequencing data from their baseline tumor samples (N=254 patients out of 455 from the original cohort) were included in the current study. The primary endpoint, pCR, was defined as ypT0/is ypN0. Logistic regression was used for analysis of pCR. Cox regression univariate and multivariate (adjusted for clinicopathological parameters and treatment arms) analyses were performed. Results: In the total cohort analyzed, high PD1 (odds ratio, OR: 1.4, P=0.03), PDL2 (OR: 1.4, P=0.04), CTLA4 (OR: 1.4, P=0.03) and TGFβ3 (OR: 1.4, P=0.02) expression was associated with an increased probability of achieving pCR at the multivariate analysis. ERBB2 (HER2) expression was associated with pCR in the three arms (T: OR: 2.7, P=0.02; L: OR: 2.3, P=0.01; T+L: OR: 5, P<0.001). Additionally in the T+L arm, PAM50 HER2-enriched subtype (OR: 2.9, P=0.03), as well as immune genes PD1 (OR: 2.1, P=0.01), PDL1 (OR: 1.8, P=0.03) and CTLA4 (OR: 2; P=0.01), were also associated with pCR. Conclusions: In the NeoALTTO population examined, PD1, PDL2, CTLA-4 and TGFβ3 expression at diagnosis were all associated with improved pCR rates after anti-HER2 treatment. The effect of these treatments seemed to be dependent on HER2 expression levels, which was particularly relevant in the T+L arm. These observations confirm previous findings that link immune infiltrates to higher pCR rates, demonstrate the clinical significance of the PD-1 pathway and additionally show that CTLA-4 and TGFβ3 could also be important in early stage HER2-positive BC. The association of tumors linked with immune regulatory gene expression with positive responses to neoadjuvant anti-HER2 agents suggests that they act in a way that reinvigorates the antitumor immunity in the face of tumor-mediated suppression. Patients whose tumors highly express these genes may be good candidates for immunotherapy before the start or after the neoadjuvant treatment when residual disease is detected at surgery, although these hypotheses require further confirmation. Citation Format: Cinzia Solinas, Pushpamali De Silva, David Venet, Soizic Garaud, Chunyan Gu-Trantien, Florentine Hilbers, Evandro de Azambuja, Olena Werner, Lorena De la Peña, Amylou Dueck, Serena Di Cosimo, Istvan Lang, Jens Huober, Sherko Küemmel, Carsten Denkert, Roberto Salgado, Christos Sotiriou, Martine Piccart-Gebhart, Debora Fumagalli, Karen Willard-Gallo. Immune regulatory gene expression and clinical outcome in the NeoALTTO trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3132.