Sentinel Lymph Node Biopsy Group Research Articles

Abstract PS01-03: What to expect from the No axillary surgical treatment for lymph node-negative patients after ultra-sonography [NAUTILUS] trial (KBCSG-21): Clinicopathologic characteristics and axillary lymph node status of enrolled patients

Abstract Purpose: The primary role of sentinel lymph node biopsy (SLNB) for early breast cancer (BC) is axillary staging. In terms of clearance of axillary disease or prevention of recurrence, its role may be limited considering the low axillary recurrence rate of less than 2% even though false-negative rates are 5-10% and the 25% additional axillary lymph node (ALN) detection in the ALND arms of the ACOSOG Z0011 and AMAROS trials. The NAUTILUS trial (NCT04303715) randomized cT1-2/N0 BC patients planned for breast-conserving surgery to evaluate the non-inferiority of omitting SLNB regarding 5-year invasive disease-free survival. The secondary endpoints are overall survival, distant metastasis-free survival, axillary recurrence rate, and quality of life of the patients. We aimed to investigate the clinicopathologic characteristics and ALN status of the subjects enrolled in the NAUTILUS trial. Methods: NAUTILUS trial randomized 1,734 subjects into SLNB or no-SLNB arms from September 2020 to October 2022. Axillary ultrasonography was mandatory to determine clinical N0, defined as no suspicious ALN or no tumor on ultrasound-guided biopsy of suspicious ALN. Clinicopathologic variables and the ALN status of the SLNB arm were analyzed. Results: Among 1,734 enrolled subjects, 828 (50.3%) and 818 (49.7%) subjects in the SLNB and no-SLNB arms, respectively, were included for analysis. Clinical and pathologic T stage, hormonal receptor/HER2 status, histologic grade, age, menopausal status, and Ki-67 were evenly distributed between the two groups (p = 0.554, 0.350, 0.056, 0.369, 0.623, 0.725 and 0.214, respectively). Median age was 55.3 (range, 48.0-62.0) years, and 661 (40.2%) were premenopausal. Overall, 30 (1.8%), 1,382 (84.0%), and 229 (13.9%) subjects were pTmic, pT1, and pT2, respectively, and median tumor size was 1.3 cm (range, 0.1-5.0). In the SLNB group, 94 (11.4%) had ALN metastasis, of which 9 (1.1%), 78 (9.4%), and 5 (0.6%) were pN1mic, pN1, and pN2-3, respectively (Table 1). According to pathologic tumor size, 5.8% (16/279), 11.4% (48/421), and 23.8% (30/126) were ALN positive for ≤ 1.0 cm, >1.0cm & ≤ 2.0 cm, and > 2.0 & ≤ 5.0 cm, respectively. The clinical and pathologic tumor size distribution among subjects with ALN metastasis were 23 (24.5%), 43 (45.7%), 9 (9.6%) and 16 (17.0%), 48 (51.1%), 30 (31.9%), respectively, for ≤ 1.0 cm, >1.0cm & ≤ 2.0 cm, and > 2.0 & ≤ 5.0 cm (Table 2). Among them, 12 (12.8%) received subsequent ALND. There was no difference in ALN metastasis rate according to molecular subtype, histologic grade, age, menopausal status, and Ki-67 (p= 0.812, 0.204, 0.671, and 0.101, respectively). Conclusions: The NAUTILUS trial completed enrollment of 1,734 subjects, among which 1,646 are available to analyze basic clinicopathologic characteristics. The trial included 229 (13.9%) pT2 and 661 (40.2%) premenopausal subjects and is expected to show the impact of SLNB omission in these subgroups. Data lock is expected in October 2027. Patients characteristics SLNB, sentinel lymph node biopsy; LVI, lymphovascular invasion; IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; HER2, anti-human epidermal growth factor-2; BCS, breast conserving surgery; TM, total mastectomy; ALND, axillary lymph node dissection Basic characteristics for sentinel lymph node biopsy group a revealed no lymph node metastasis by fine needle aspiration or gun biopsy ALN, axillary lymph node; LN, lymph node Citation Format: Jai Min Ryu, Han-Byoel Lee, Sei Hyun Ahn, Il-Yong Chung, Seeyoun Lee, Seho Park, Woosung Lim, Joon Jeong, Jeong Eon Lee, Eunhye Kang, Ji Hyun Chang, Jung Min Chang, Woo Kyung Moon, Wonshik Han, Eun-Kyu Kim. What to expect from the No axillary surgical treatment for lymph node-negative patients after ultra-sonography [NAUTILUS] trial (KBCSG-21): Clinicopathologic characteristics and axillary lymph node status of enrolled patients [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 PS01-03.

Abstract PS01-02: Long-term outcomes of sentinel lymph node biopsy following neoadjuvant chemotherapy for initially node-positive breast cancer: A systematic review and meta-analysis

Abstract Background: Sentinel lymph node biopsy (SLNB) alone is now frequently offered to women with initially node-positive breast cancer who convert to pathologically node negative (nodal pCR) following neoadjuvant chemotherapy (NAC), despite limited long-term data regarding the oncologic safety of this approach. The aim of this meta-analysis was to evaluate the long-term oncologic outcomes associated with SLNB alone following NAC for initially node-positive breast cancer. Methods: A systematic review and meta-analysis was conducted according to PRISMA guidelines. Medline (Ovid), Embase, and Cochrane Central Registry were systematically searched for studies comparing women undergoing SLNB or ALND following NAC for initially clinically node-positive breast cancer. Included studies reported one of the following outcomes: axillary recurrence (AR), locoregional recurrence (LRR), disease-free survival (DFS) or overall survival. A random effects meta-analysis was used to calculate weighted pooled effect estimates (risk ratios, RR) for all outcomes. Variability across studies due to heterogeneity was estimated using I2 statistics. Subgroup analysis was performed by length of follow-up for each study. Risk of bias within studies was assessed using the Newcastle-Ottawa Scale (NOS). Results: Data for participants undergoing treatment between 2004 and 2022 was captured across studies. The median age of women treated with NAC for initially node-positive breast cancer ranged from 46 to 60 years. The median follow-up time ranged from 19.5 to 108 months across included studies. Nine observational studies were eligible for meta-analysis. No studies were excluded from the analysis on the basis of quality: Newcastle-Ottawa Scale scores ranged from 6 to 9 (maximum possible score of 9). Rates of axillary recurrence (AR) were low across all included studies (range 0.0% to 5.6%). For AR, data for 2,882 patients from 7 studies was quantitatively synthesized (SLNB=1,964; ALND=917). For LRR, data for 2,629 patients from 7 studies was quantitatively synthesized (SLNB=1,857; ALND=771). No significant differences were observed in AR between patients undergoing SLNB alone versus ALND following NAC for initially node-positive breast cancer: pooled RR 1.02 (95% CI: 0.46-2.29, I2=0.0%). Similarly, no significant differences were observed in LRR (RR 0.70, 95% CI: 0.45-1.10, I2=0.0%), DFS (RR 0.77, 95% CI: 0.55-1.08, I2=0.0%), nor overall mortality (RR 0.66, 95% CI: 0.33-1.33, I2=0.0%) between the SLNB and ALND groups. Conclusions: Among patients who convert to node-negative following NAC, this meta-analysis suggests that SLNB alone does not result in significantly different oncologic outcomes compared to ALND, and that de-escalation of axillary surgery to SLNB alone in this context may be safely considered in this patient population. Citation Format: Mariam Rana, Anna Weiss, Alison Laws, Carol Mita, Tari King. Long-term outcomes of sentinel lymph node biopsy following neoadjuvant chemotherapy for initially node-positive breast cancer: A systematic review and meta-analysis [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 PS01-02.

Changes in lymph node surgery in breast cancer and preoperative drug prescription analysis for postoperative pain management: A retrospective, cross-sectional study.

This study aimed to investigate the changes in lymph node surgery types and prescription patterns of postoperative medications for pain management in patients with breast cancer using national health insurance claim data from South Korea. The study population comprised patients with at least one record of a principal diagnosis of breast cancer (ICD-10 code: C50) from the national health insurance claim database between 2010 and 2019. Patients who underwent mastectomy or lumpectomy only once were selected for the analysis. Patients who underwent axillary lymph node dissection (ALND) with mastectomy or lumpectomy on the day of surgery were included in the ALND group, whereas those who underwent sentinel lymph node biopsy (SLNB) were included in the SLNB group. Prescription records of opioids before, after and on the date of breast cancer surgery were collected and categorized according to the opioid type. Multivariate logistic regression modeling was used to compare postoperative opioid prescriptions. The proportion of those undergoing ALND among 3,080 patients decreased consistently after 2014, while the proportion undergoing SLNB increased. Although the rate of pain medication prescription on the day of surgery was similar between the two groups, the rate of prescription of postoperative pain medication and anticancer agents was lower in the SLNB group than in the ALND group. Logistic regression modeling showed that the SLNB group had lower odds of receiving opioids than did the ALND group (Odds ratio (OR) = 0.727, Confidence Interval (CI) = 0.546-0.970). A consistent trend was observed when the model was adjusted for neoadjuvant chemotherapy and the use of preoperative pain medications (OR = 0.718, CI = 0.538-0.959). To manage postoperative pain and prevent chronic pain with minimal side effects, sufficient discussion among clinicians, patients, and other healthcare professionals is imperative, along with adequate treatment planning.

Oncological Safety of Skipping Axillary Lymph Node Dissection in Patients with Clinical N0, Sentinel Node-Positive Breast Cancer Undergoing Total Mastectomy

ObjectiveThis study aimed to determine whether sentinel lymph node biopsy (SLNB) alone could afford oncological outcomes comparable with axillary lymph node dissection (ALND) in patients with early breast cancer without palpable lymphadenopathy who underwent total mastectomy (TM) and were SLN-positive.MethodsThis study analyzed clinical data of 6747 patients with breast cancer who underwent TM between 2014 and 2018 in two tertiary hospitals in Korea. Overall, 643 clinical stage T1-3 N0 patients who did not receive neoadjuvant therapy and had one to two metastatic SLNs at the time of surgery were included. Propensity score matching was performed between the SLNB alone and ALND groups, adjusting for clinical T stage and number of metastatic SLNs. In total, 237 patients were allocated to each group.ResultsMean number of metastatic SLNs was 1.2 for the SLNB group and 1.6 for the ALND group. With a median follow-up of 65.0 months, 5 year disease-free survival was 90.8% for the SLNB group and 93.9% for the ALND group (hazard ratio [HR] 1.35, 95% confidence interval [CI] 0.70–2.58; p = 0.36). 5 year ipsilateral locoregional recurrence-free survival (LRRFS) was not significantly different between the two groups (95.1% and 98.3% for the SLNB and ALND groups, respectively) [HR 1.86, 95% CI 0.69–5.04; p = 0.21]. In the SLNB group, patients who received radiation therapy (RT) showed superior 5 year LRRFS than patients who did not receive RT (100% vs. 92.9%; p = 0.02).ConclusionCollectively, our findings suggest that SLNB could afford comparable outcomes to ALND in patients with early breast cancer and one to two metastatic SLNs who underwent TM. Importantly, RT could decrease locoregional recurrence in patients who underwent SLNB alone.

Oncologic Outcome of Robotic-Assisted and Laparoscopic Sentinel Node Biopsy in Endometrial Cancer.

Recently, sentinel lymph node biopsy (SLNB) has been introduced in the surgical staging of endometrial cancer as an alternative to systematic lymph node dissection (LND). However, the survival impact of SLNB is not yet well characterised. We performed a retrospective study of 419 patients with endometrial cancer treated with SLNB alone or with pelvic and para-aortic LND. For SLNB mapping, indocyanine green was used. Median follow-up was 66 months. After exclusions, 337 patients were eligible for analysis. Of them, 150 underwent SLNB and 187 LND. During the follow-up time, 27 (24.7%) of the 150 who underwent SLNB and 54 (28.9%) of the 187 who underwent LND were diagnosed with recurrent disease (p = 0.459). The estimated 5-year disease-free survival (DFS) rate was 76.7% and 72.2% for patients in the SLNB and LND group, respectively (p = 0.419). The 5-year overall survival (OS) rates were 80.7% and 77.0% in the SLNB and LND group, respectively (p = 0.895). Survival rates were similar in both groups independent of lymph node status. Multivariable analysis confirmed that the staging approach was not associated with oncological outcome. For patients without lymph node metastases, patient outcome was worsened by advanced tumour stage and non-endometrioid tumour histology. In the group of patients with confirmed lymph node metastases, advanced tumour stage and inadequate adjuvant treatment significantly reduced DFS and OS. Our data suggested that SLNB did not compromise the oncological outcome of patients with endometrial cancer compared to LND.

The Impact of Sentinel Lymph Node Biopsy on Female Patients With T3-4c Breast Cancer and 1-2 Positive Lymph Nodes: A Population-Based Cohort Study

PurposeThis study aimed to evaluate the efficacy of sentinel lymph node biopsy (SLNB) in patients diagnosed with cT3-4c breast cancer with no more than 2 positive sentinel lymph nodes. MethodsUsing data from the Surveillance, Epidemiology, and End Results (SEER) database, this retrospective study identified patients diagnosed with T3-4c breast cancer between 2010 and 2015. These patients were then categorized into 2 groups: the SLNB group, which underwent examination of 1-5 regional lymph nodes and the axillary lymph node dissection (ALND) group, which underwent examination of ≥10 regional lymph nodes. Propensity score matching analysis was used to assess the efficacy of SLNB in cT3-4c patients. ResultsA total of 1139 patients were included in the analysis, with 423 and 716 patients in the SLNB and ALND groups, respectively. The 10-year overall survival (OS) and breast cancer-specific survival (BCSS) rates in the SLNB group were 66.1% and 76.3%, respectively, compared with 66.0% and 73.8%, respectively. Statistical analysis revealed no significant differences between the 2 groups in terms of OS (HR = 1.00, 95% CI = 0.80-1.25, P = .997) and BCSS (HR = 1.08, 95% CI = 0.83-1.41, P = .551). Even after 1:1 propensity score matching, there were no significant differences in OS (HR = 0.87, 95% CI = 0.65-1.16, P = .341) and BCSS (HR = 0.82, 95% CI = 0.59-1.16, P = .266) between the 2 groups. ConclusionThis study demonstrates that SLNB does not adversely affect the survival of cT3-4c breast cancer patients with 1-2 sentinel lymph node metastases.

The incidence and cost implications of surgical site infection following lymph node surgery for skin malignancy

Lymph node surgery is commonly performed in the staging and treatment of metastatic skin cancer. Previous studies have demonstrated sentinel lymph node biopsy (SLNB) and, particularly, lymph node dissection (LND) to be plagued by high rates of wound complications, including surgical site infection (SSI) and seroma formation. This study evaluated the incidence of wound complications following lymph node surgery and provided the first published cost estimate of SSI associated with lymph node surgery in the UK. A retrospective cohort study of 169 patients with a histological diagnosis of primary skin malignancy who underwent SLNB or LND of the axilla and/or inguinal region at a single tertiary centre over a 2 year period was conducted. Demographic, patient risk factor, and operation characteristics data were collected and effect on SSI and seroma formation was analysed. Cost-per-infection was estimated using National Health Service (NHS) reference and antibiotic costs. A total of 146 patients underwent SLNB with a SSI rate of 4.1% and a seroma incidence of 12.3%. Twenty-three patients underwent LND with a SSI rate of 39.1% and a seroma incidence of 39.1%. Seroma formation was strongly associated with the development of SSI in both the SLNB (odds ratio (OR) =18.0, p<0.001) and LND (OR = 21.0, p=0.007) group. The median additional cost of care events and treatment of SSI in the SLNB and LND groups was £199.46 and £5187.04, respectively. SSI remains a troublesome and costly event following SLNB and LND. Further research into perioperative care protocols and methods of reducing lymph node surgery morbidity is required and could result in significant cost savings to the NHS.

Sentinel Lymph Node Biopsy vs No Axillary Surgery in Patients With Small Breast Cancer and Negative Results on Ultrasonography of Axillary Lymph Nodes

Sentinel lymph node biopsy (SLNB) is the standard of care for axillary node staging of patients with early breast cancer (BC), but its necessity can be questioned since surgery for examination of axillary nodes is not performed with curative intent. To determine whether the omission of axillary surgery is noninferior to SLNB in patients with small BC and a negative result on preoperative axillary lymph node ultrasonography. The SOUND (Sentinel Node vs Observation After Axillary Ultra-Sound) trial was a prospective noninferiority phase 3 randomized clinical trial conducted in Italy, Switzerland, Spain, and Chile. A total of 1463 women of any age with BC up to 2 cm and a negative preoperative axillary ultrasonography result were enrolled and randomized between February 6, 2012, and June 30, 2017. Of those, 1405 were included in the intention-to-treat analysis. Data were analyzed from October 10, 2022, to January 13, 2023. Eligible patients were randomized on a 1:1 ratio to receive SLNB (SLNB group) or no axillary surgery (no axillary surgery group). The primary end point of the study was distant disease-free survival (DDFS) at 5 years, analyzed as intention to treat. Secondary end points were the cumulative incidence of distant recurrences, the cumulative incidence of axillary recurrences, DFS, overall survival (OS), and the adjuvant treatment recommendations. Among 1405 women (median [IQR] age, 60 [52-68] years) included in the intention-to-treat analysis, 708 were randomized to the SLNB group, and 697 were randomized to the no axillary surgery group. Overall, the median (IQR) tumor size was 1.1 (0.8-1.5) cm, and 1234 patients (87.8%) had estrogen receptor-positive ERBB2 (formerly HER2 or HER2/neu), nonoverexpressing BC. In the SLNB group, 97 patients (13.7%) had positive axillary nodes. The median (IQR) follow-up for disease assessment was 5.7 (5.0-6.8) years in the SLNB group and 5.7 (5.0-6.6) years in the no axillary surgery group. Five-year distant DDFS was 97.7% in the SLNB group and 98.0% in the no axillary surgery group (log-rank P = .67; hazard ratio, 0.84; 90% CI, 0.45-1.54; noninferiority P = .02). A total of 12 (1.7%) locoregional relapses, 13 (1.8%) distant metastases, and 21 (3.0%) deaths were observed in the SLNB group, and 11 (1.6%) locoregional relapses, 14 (2.0%) distant metastases, and 18 (2.6%) deaths were observed in the no axillary surgery group. In this randomized clinical trial, omission of axillary surgery was noninferior to SLNB in patients with small BC and a negative result on ultrasonography of the axillary lymph nodes. These results suggest that patients with these features can be safely spared any axillary surgery whenever the lack of pathological information does not affect the postoperative treatment plan. ClinicalTrials.gov Identifier: NCT02167490.

Strict versus Liberal Use of Sentinel Node Biopsy in Breast Cancer Surgery: Any Clinical Outcome Differences? A 20-Year Clinical Experience

Introduction: As applied to early breast cancer (BC) patients, sentinel node biopsy (SNB) has undergone major changes over the years, especially concerning the widening of indication criteria or skipping systematic axillary lymph node dissection (ALND) after a positive SN. We aimed to ascertain whether a strict versus a more liberal use of SNB resulted in different clinical outcomes in our clinical experience. Methods: We studied consecutive BC patients undergoing SNB between January 1, 2000, and March 31, 2020. There were 1,587 patients and 1,634 SNB procedures. Cases were divided into two study groups: the “strict” SNB group (unifocal tumors up to 35 mm in which ALND was always performed for a positive SN, amounting to 1,183 SNBs), and the “liberal” SNB group (extended tumor size up to selected T3 cases, as well as multifocal or bilateral disease, and patients with previous contralateral BC, not always followed by ALND after a positive SN, amounting to 451 SNBs). Patients were closely followed up to the end of the study. Results: Clinico-pathological variables were strikingly different between study groups, with the liberal group showing a higher risk profile. Cox regression analysis for disease recurrence did not show significant differences in axillary, lymph node, or locoregional recurrence rates or distant relapse. There were no differences in survival between groups. Conclusion: It seems reasonable to adopt the liberal SNB approach, as the goal of surgical management in early BC patients must be attaining optimal locoregional disease control, no matter the differences in distant metastatic spread rates across different BC risk profiles.

The Efficacy of Axillary Reverse Mapping for the Prevention of Lymphedema.

Lymphedema (LE) is the most notable complication of axillary surgery. The axillary reverse mapping (ARM) technique was created to decrease LE. This study aims to evaluate a single surgeon's experience with ARM in patients undergoing sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND) for breast cancer. We retrospectively analyzed patients who underwent SLNB or ALND. Tumor characteristics and treatments received were evaluated. Surgical intervention and use of ARM were compared to assess LE rates. A subgroup analysis was also performed of patients who underwent NAC. LE was initially reported in 7.1% (n = 10) of patients; 3.3% (n = 4) with SLNB and 35% (n = 6) with ALND. At initial follow-up, LE was reported 16.4% more often in patients who underwent ALND with no ARM, and 38.8% more often in patients who underwent ALND plus ARM. An increased risk of LE was found in patients treated with ALND (OR = 16.0, P < .001). All patients who underwent ARM were 12.75% more likely to develop LE if they received NAC (P < .05). Patients in the ALND group who also received NAC were more likely to undergo ARM as compared with patients in the SLNB group (P < .01). Our study showed that ARM failed to decrease the incidence of LE. Until better surgical outcomes are shown for the prevention of LE using ARM, other approaches should be utilized. However, larger prospective studies are needed to evaluate ARM.

Survival benefit of sentinel lymph node biopsy in Asian melanoma patients.

Sentinel lymph node biopsy (SLNB) provides important prognostic information for early-stage melanomas. However, statistics regarding the survival comparison between SLNB and nodal observation in Asia, where acral lentiginous melanoma (ALM) predominates, are limited. This study aimed to identify if SLNB offered survival benefits over nodal observation in early-stage melanomas in Taiwan. The retrospective study included 227 patients who met the SLNB criteria according to the National Comprehensive Cancer Network guidelines and were treated at National Taiwan University Hospital from June 1997 to June 2021. Survival analysis was performed using Kaplan-Meier curves and Cox proportional hazards regression models. Of the study population, ALM accounted for 73.1%; 161 patients (70.9%) underwent SLNB and 66 patients (29.1%) were under nodal observation. Multivariate analysis showed significantly improved melanoma-specific survival (hazard ratio [HR], 0.6; p = .02) in the SLNB group. Among those who underwent completion lymph node dissection (CLND), the non-sentinel node positivity rate was 44.4%. Immediate CLND resulted in significantly longer melanoma-specific survival and distant-metastasis-free survival (DMFS) compared to nodal observation. (HR, 0.2; p = .01 for melanoma-specific survival. HR, 0.3; p = .046 for DMFS). In conclusion, SLNB may provide survival benefits of cutaneous melanoma over nodal observation in the Taiwanese population.

Eccrine Porocarcinoma: Clinical and Histopathological Study of 14 Patients with Special Emphasis on Sentinel Lymph Node Biopsy.

Eccrine porocarcinoma is a rare skin adnexal tumour that affects elderly people. Most eccrine porocarcinomas are stage I or II according to the American Joint Committee on Cancer. The prognosis is good in early stages, but worsens when advanced. Since information on the use of sentinel lymph node biopsy in these patients is scarce, this study examined the records of all patients with eccrine porocarcinoma treated at Helsinki University Hospital during a 17-year period and focused on sentinel lymph node biopsy patients. The study identified 14 patients (9 male, 5 female). There were 2 metastases to the lymph nodes and 2 recurrences at initial referral to our institution. All primary tumours had wide local excision and 6 patients also had sentinel lymph node biopsy, of whom none had positive lymph nodes. There were no new metastases or recurrences during follow-up. Three patients died of causes other than eccrine porocarcinoma. When comparing the wide local excision only and wide local excision with sentinel lymph node biopsy groups, no parameters reached statistical significance. The decision process of the multidisciplinary tumour board meeting on whether to perform sentinel lymph node biopsy was not clear, perhaps due to the limited knowledge of eccrine porocarcinoma. Further studies and international collaboration are warranted.

Lymphatic Complications Following Sentinel Node Biopsy or Pelvic Lymphadenectomy for Endometrial Cancer.

Sentinel node biopsy (SNB) is performed worldwide in patients with endometrial cancer (EC). The aim of this study was to evaluate and compare the occurrence rate of lymphatic complications between SNB and pelvic lymphadenectomy (LND) for EC. The medical records of women who underwent SNB or pelvic LND for EC between September 2012 and April 2022 were assessed. A total of 388 patients were enrolled in the current study. Among them, 201 patients underwent SNB and 187 patients underwent pelvic LND. The occurrence rates of lower-extremity lymphedema (LEL) and pelvic lymphocele (PL) were compared between the patients who underwent SNB and those who underwent pelvic LND. The SNB group had a significantly lower occurrence rate of lower-extremity LEL than the pelvic LND group (2.0% vs. 21.3%, p < 0.01). There were no patients who had PL in the SNB group; however, 4 (2.1%) patients in the pelvic LND group had PL. The occurrence rates of lower-extremity LEL and PL were significantly lower in patients who underwent SNB than those who underwent pelvic LND. SNB for EC has a lower risk of lymphatic complications compared to systemic LND.

Axillary surgery efficacy for patients with breast cancer receiving neoadjuvant chemotherapy on NSABP B40 and B41.

524 Background: Alliance A011202 is evaluating the efficacy of axillary lymph node dissection (ALND) compared to regional nodal irradiation (RNI) for patients with cN1 breast cancer who receive neoadjuvant chemotherapy (NCTX) that becomes ycN0 but remains pN+. In the absence of its publication, level I guidance does not exist regarding the optimal axillary surgery for patients receiving NCTX. We sought to evaluate outcomes across two national contemporary clinical NCTX trials based on axillary and breast response to NCTX, particularly if more aggressive surgery was associated with more favorable outcomes. Methods: With IRB approval (IRB201802781), we obtained data from NCTX trials NSABP B40 and B41. B40 enrolled women with HER2- disease, and B41 enrolled those with HER2+ disease. RNI and axillary surgery were selected at physician discretion and not protocolled. Patients received sentinel lymph node biopsy (SLNB), SLNB+ALND (S+ALND), or ALND. We examined outcomes of locoregional recurrence (LRR), distant recurrence (DR), disease free survival (DFS), and overall survival (OS). Univariable and multivariable analyses of B40 and B41 data were performed to evaluate the associations of axillary surgery with the outcomes above, adjusting for age, tumor subtype, mastectomy or not, breast pathologic complete response (pCR), axillary pCR, tumor subtype, regional nodal irradiation, and grade. Kaplan-Meier estimation was used for OS and DFS, with cumulative incidence function for LRR and DR. Results: Median follow-up for studies B40 and B41 were 4.5 and 5.1 years, respectively, including 1154 and 504 patients for analysis. A total of 786 (47%) patients were cN+, and of those, 377 had a pcR (48%). 440 (27%), 505 (31%), and 663 (41%) patients had SLNB, S+ALND, and ALND respectively. 855 (52%) and 803 (48%) patients had mastectomy and lumpectomy, respectively. 783 (51%) received RNI. For the 518 ypN+ patients on B40, 7/25 (SLNB), 69/234 (S+ALND), and 107/259 (ALND) experienced an event. DFS at 5 years was 71%, 68%, and 56% for the SLNB, S+ALND, and ALND groups respectively with ypN+ on B40. For the 112 ypN+ patients on B41, 3/6, 15/43, and 27/63 experienced an event. DFS at 5 years was 50%, 64%, and 55% for the SLNB, S+ALND, and ALND groups, respectively, with ypN+ on B41. In multivariable analyses for the combined population of B40 and B41 for LRR, DR, DFS, and OS, SLNB was never associated with a higher chance of relapse or inferior survival (HR &gt; 1) compared to S+ALND or ALND. Conclusions: Among women prospectively treated on national trials with NCTX and axillary surgery and RNI selected at physician discretion, receipt of SLNB alone was not associated with a higher likelihood of recurrence compared to S+ALND or ALND. Anticipated results of A011202 will provide level I guidance on axillary surgery for patients with cN1 disease converting to cN0 post-NCTX.

Oncologic outcomes for different axillary staging techniques in nodal positive breast cancer undergoing neoadjuvant systematic treatment: A cancer registry study.

e12571 Background: The optimal axillary staging technique for patients with nodal positive breast cancer undergoing neoadjuvant systemic treatment (NAST) is unclear. Less invasive, targeted approaches like targeted axillary dissection (TAD) or sentinel-lymph node biopsy (SLNB) recently showed false-negative rates &lt; 10% compared to axillary lymph node dissection (ALND). Oncologic outcomes, however, are unknown. Methods: We identified nodal positive breast cancer patients undergoing NAST from 2016 to 2021 with at least 1-year follow-up and available information regarding axillary staging from the state cancer registry of Baden-Wuerttemberg, Germany. Invasive disease-free survival (iDFS) was assessed using Kaplan-Meier statistics and multivariate cox regression models (adjusted for age, pN stage, pT stage, and tumor biologic subtype). Results: A total of 2403 patients with a median follow-up of 23.2-months after surgery were identified: 1963 underwent ALND, 407 underwent SLNB (in 230 cases, three or more sentinel nodes (SLNs) were removed and in 177 cases, 1-2 SLNs were removed), and 33 underwent TAD. The proportion of patients with pN+ stage within these four groups was 54%, 31%, 26%, and 35%, respectively ( P &lt; 0.001). Significant differences in iDFS between the ALND, SLNB, and TAD groups were observed (log rank P = 0.046): iDFS 2 years after surgery was 74.5% (ALND), 80.2% (SLNB ≥3 removed SLNs), 85.6% (SLNB &lt; 3 removed SLNs), and 88.4% (TAD), respectively. iDFS after 4 years was 61.5% (ALND), 69.1% (SLNB ≥3 removed SLNs), and 74.6% (SLNB &lt; 3 removed SLNs), respectively. Multivariate cox regression analysis showed no significant influence of different axillary staging techniques on iDFS: HR 0.91 (95% CI 0.55 to 1.52) for SLNB with ≥3 removed SLNs, HR 0.99 (95% CI 0.59 to 1.67) for SLNB with &lt; 3 removed SLNs (reference = ALND). Conclusions: This data suggests that ALND provides no benefit in terms of iDFS compared to targeted approaches like TAD or SLNB for patients with nodal positive breast cancer undergoing NAST. Future studies with longer-term follow-up are welcomed to fully inform this discussion.

Sentinel Lymph Node Impact on the Quality of Life of Patients with Endometrial Cancer.

Given the improvement in the surgical treatment of endometrial cancer with the inclusion of sentinel lymph node biopsy (SLNB), our aim was to evaluate the impact of this minimally invasive and tailored nodal assessment on patients' quality of life (QoL). This was a cross-sectional study conducted in a single-centre, tertiary-level hospital. Patients diagnosed with preoperative early-stage endometrial cancer, who underwent primary surgical treatment between August 2015 and November 2021, were included. The enrolled patients were divided into two cohorts according to the nodal staging performed: the first group underwent only SLNB (SLNB group); the second group underwent pelvic and/or para-aortic lymphadenectomy (LND group). We evaluated the overall QoL using the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life core 30-item questionnaire (EORTC QLQ-C30) and a sexual health questionnaire (EORTC SHQ-C20). The scores were compared between the groups. Ninety patients were enrolled in the study: 61 (67.8%) in the SLNB group and 29 (32.2%) in the LND group. In the LND group, 24 (82.7%) patients underwent pelvic and para-aortic LND, while 5 (17.3%) patients underwent pelvic LND. The assessment of the functional scales showed better results for the SLNB group than for the LND group, with a significantly lower impact on physical status (8.2% vs. 25%, respectively; p = 0.031). In terms of the symptom scales, the SLNB group reported a significantly lower negative impact on sleep quality (4.9% vs. 27.6%, respectively; p < 0.01), pain (1.6% vs. 13.8%, respectively; p = 0.019), and dyspnoea (0% vs. 10.3%, respectively; p = 0.011) than the LND group. The SLNB group had better results for all analysed items regarding sexual QoL. The implementation of a surgical technique with SLNB improved patients' overall QoL by increasing their well-being in the functional and symptom spheres.

Survival After Sentinel Lymph Node Biopsy Compared with Axillary Lymph Node Dissection for Female Patients with T3-4c Breast Cancer.

For patients with cN0 and T1-2 breast cancer, sentinel lymph node biopsy (SLNB) can provide survival results equivalent to axillary lymph node dissection (ALND). However, whether it can be performed on T3-4c patients is still controversial. Female patients diagnosed with cN0, T3-4c, and M0 breast cancer from 2004 to 2019 were identified using the surveillance, epidemiology and end results (SEER) database and divided into 2 groups, the SLNB group (1-5 regional lymph nodes examined) and the ALND group (≥10 regional lymph nodes examined). Finally, only those with pN0 disease were included in the SLNB group. The baseline differences in clinicopathological characteristics between groups were eliminated by propensity score matching (PSM). We also conducted subgroup analyses according to age, overall TNM stage, breast cancer subtypes, surgical approaches, radiation therapy, and chemotherapy. The primary endpoint was survival. With a mean follow-up of 75 months, a total of 186 deaths were reported among 864 patients. The overall survival (OS) and breast cancer-specific survival (BCSS) in the SLNB group were 78.2% and 87.5%, respectively, and that in the ALND group were 78.7% and 87.3%, respectively. The unadjusted hazard ratio (HR) for OS and BCSS in the SLNB group (vs. the ALND group) was 0.922 (95% CI, 0.691-1.230, P = .580) and 0.874 (95% CI, 0.600-1.273, P = .481), respectively. Besides, the OS and BCSS between the 2 groups were also similar in all subgroup analyses. SLNB may be performed on female patients with cN0, T3-4c, and M0 breast cancer.

Abstract PD15-02: PD15-02 Long Term Outcome in Patients with Nodal-Positive Breast Cancer Treated with Sentinel Lymph Node Biopsy Alone After Neoadjuvant Chemotherapy

Abstract Importance: The use of neoadjuvant chemotherapy (NAC) in the clinical care of breast cancer patients has increased considerably over recent years especially in node positive cases. For patients who have axillary nodal metastases prior to NAC, the prevailing standard of care is to undergo an axillary lymph node dissection (ALND), regardless of response to therapy. Sentinel lymph node biopsy (SLNB) has yet to be accepted as the standard staging procedure in patients who had clinical complete response in the axilla following NAC. This is due to the presumed high false negative rate associated with SLNB in such scenario. But there are limited data on the long term outcome of these patients who are only treated with SLNB alone. Aim: A retrospective cohort study comparing the long term outcome of breast cancer patients with clinically node positive disease (N1) but turned clinically node negative (N0) following NAC, receiving SLNB alone versus ALND. Methods: Patients who had pathologic proven N1 breast cancer (before NAC) treated with NAC and turned clinically N0 from January 2009 to December 2014 were identified from Asan Medical Center breast cancer database in South Korea. Primary endpoint was axillary recurrence rate (ARR) and secondary endpoints were disease-free survival (DFS) and overall survival (OS). These outcomes were reported for patients who had SLNB alone versus ALND. Results: 561 patients with clinically stage N1 (cN1) cancer treated with NAC and turned clinically stage N0 (cN0) were identified. 253 (45.1%) patients received SLNB only while 308 (54.9%) patients had ALND. The clinicopathological features of these patients were illustrated in Table 1. Majority of these patients received adjuvant radiotherapy, 81.2% in the SLNB group and 76.5% in the ALND group. In the pathologically stage N0 (ypN0) group, at a median follow up of 69 months, ARR was 3.0% in the SLNB only group and 1.7% in the ALND group (p=0.704). DFS and OS were not significantly different between patients with SLNB alone versus ALND (p= 0.561 and 0.810 respectively). Median number of SLN harvested in the SLNB only group is 5 (range 1 -17). In the pathologically stage N1 (ypN1) group with only 1-2 lymph node positive for metastasis, at a median follow up of 66 months, ARR was 5.8% in the SLNB group and 4.7% in the ALND group (p=0.768). There was no significant difference in DFS and OS between the SLNB and ALND group (p=0.537 and 0.645). In the SLNB only group, the median number of positive lymph node was 1 (range 1-2), the median number of sentinel lymph node was 6 (range 2-18). Conclusion: In cN1 breast cancer patients who were converted to cN0 following NAC, axillary recurrences were rare. No statistically significant differences were noted in DFS and OS between patients with SLNB or ALND. Our findings suggest that these patients may be safely treated with SLNB only, even when there are up to 2 positive SLNs. Table 1 Clinicopathological features of breast cancer patients with nodal disease and NAC Citation Format: Sue Zann Lim, Tae-Kyung Yoo, Sae Byul Lee, Jisun Kim, Il-Yong Chung, Beom Seok Ko, Jong Won Lee, Byung Ho Son, Sei Hyun Ahn, Hee Jeong Kim. PD15-02 Long Term Outcome in Patients with Nodal-Positive Breast Cancer Treated with Sentinel Lymph Node Biopsy Alone After Neoadjuvant Chemotherapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD15-02.

Abstract P2-14-15: Comparison of recurrence-free survival according to axillary surgery extent for clinical N0, sentinel node(s) positive, primary breast cancer patients who underwent total mastectomy

Abstract Purpose We investigated the recurrence-free survival difference between limited axillary node surgery and axillary node dissection (ALND) in clinical N0 primary breast cancer patients with one to three sentinel node metastasis who underwent total mastectomy. Method We retrospectively analyzed clinical data of 579 primary breast cancer patients who underwent total mastectomy between 2014 and 2018 from Seoul National University Hospital and Asan Medical Center. All included patients had clinical T1-2, N0 disease at the time of diagnosis based on physical exam, radiologic evaluation, and pathologic assessment if needed. The patients had one to three metastatic sentinel node(s) at the time of surgery. The patients received sentinel lymph node biopsy (SLNB) with result of one to three metastatic node(s) and either proceeded to ALND or not. We performed propensity score matching between the SLNB and ALND group with baseline clinical factors including clinical T stage and number of metastatic sentinel node(s). Finally, 208 patients were matched 1:1 for each group respectively for further analysis. Also, we stratified the eligible patients based on radiation therapy for subgroup analysis. We examined disease-free survival, regional recurrence-free survival, distant metastasis-free survival and compared the results between the groups. Result The median follow-up period was 64.7 months. Among matched cohorts, mean number of metastatic nodes on final pathology result was 1.2 for SLNB group and 1.7 for ALND group. Also, mean number of total removed nodes was 8.3 for SLNB group and 17.4 for ALND group. The disease-free survival [DFS] at 7 years was 89.7% for SLNB group and 91.1% for ALND group with no statistically significant difference. (hazard ratio [HR] 1.43, 95% confidence interval [CI] 0.70 to 2.92, p=0.32) Among patients who were treated with radiation, the DFS was 94.1% in the SLNB group and 94.4% in the ALND group. (HR, 0.82, 95% CI 0.17 to 4.0, p=0.81) For the subgroup without radiation, the DFS was 87.7% in the SLNB group and 89.4% in the ALND group. (HR, 1.68, 95% CI 0.75 to 3.75, p=0.19) We observed no statistically significant differences in the regional recurrence-free survival at 7 years (95.8% in the SLNB vs. 95% in the ALND, HR 0.62, 95% CI 0.53-4.95, p=0.39), and in the distant metastasis-free survival at 7 years (95.8% in the SLNB vs. 95% in the ALND, HR 1.28, 95% CI 0.59 to 2.73, p=0.52) Conclusion Our results suggest that limited axillary surgery with sentinel node biopsy may be as effective as axillary node dissection in terms of recurrence-free survival, for clinically node negative, primary breast cancer patients with limited metastatic sentinel node(s) who are candidates for total mastectomy. Key words: Breast cancer, Total mastectomy, Axillary lymph node dissection, Sentinel lymph node biopsy. Citation Format: Jung Whan Chun, Hong-Kyu Kim, Han-Byoel Lee, Hyeong-Gon Moon, Jong Won Lee, Wonshik Han. Comparison of recurrence-free survival according to axillary surgery extent for clinical N0, sentinel node(s) positive, primary breast cancer patients who underwent total mastectomy. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-14-15.

Abstract P5-08-11: Objective Comparison of Post-operative Activity after Sentinel Lymph Node Biopsy versus Axillary Lymph Node Dissection Using Wearable Activity Monitors – The ‘BRACELET’ Study

Abstract Introduction Axillary de-escalation is driven by both a desire to minimize injury and a growing awareness of the oncological safety of axillary conservation. However, the evidence of the impact of axillary procedures is largely subjective and based on patient questionnaires. Sensing technologies such as Wearable Activity Monitors (WAM) can acquire functional postoperative data, enabling objective analysis of patients’ physical activity (PA) levels. This technology implementation would help surgeons better comprehend the post-operative recovery phase and provide individualized interventions for patients. We aimed to use WAMs in order to investigate differences in physical recovery between axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB) – with a hypothesis that the ALND group has slower recovery compared to SLNB. Methods A single centre, prospective non-randomized observational study was conducted from September 2019 to May 2022. Consecutive patients undergoing breast and axillary surgery were identified from theatre lists. Patients with movement disorders or upper limb impairment and those using mobility devices or aids were excluded. Eligible consented patients wore WAMs (AX3, Axivity, UK – triaxial accelerometer) on both wrists at least one day pre- and up to two weeks post-operatively. The Mann-Whitney U test and the Wilcoxon Signed Rank Test were performed to analyze the PA levels between arms and surgeries. Patient demographics and potential confounders such as concomitant breast/reconstruction surgery were recorded. Results A total of 53 patients were recruited. Greater PA level was observed in the control arm compared to the surgically treated side in both SLNB and ALND groups in week 1 (SLNB: 69.6% vs 61.1%, p=0.006; ALND: 75.3% vs 60.4%, p&amp;lt; 0.001) and 2 (SLNB: 77.6% vs 71.1%, p=0.113; ALND: 81.9% vs 70.2%, p&amp;lt; 0.001) respectively. When comparing activities of the surgically treated side only, the ALND patients had significantly lower PA level compared to SLNB group in post-operative day 7-9 (65.4% vs 72.5%, p=0.035). Subgroup analysis was performed to compare surgically treated side of ‘Mastectomy Only and SLNB’ versus ‘Mastectomy Only and ALND’. PA level was significantly lower in the latter than the former in week 2 (78.5% vs 83.5%, p=0.027). There were no significant differences in demographics between the 2 groups. Conclusion ALND consistently results in decreased PA level compared to SLNB. The findings also demonstrate the longitudinal impact of SLNB, which impacts PA levels, even up to 2 weeks after surgery. Monitoring recovery objectively after breast cancer surgery provides patients and surgeons with more information about the likely outcomes of their treatment and may help them choose the best option, particularly where oncological outcomes are equivocal. This information could also be used to improve outcomes by identifying vulnerable patients who would benefit from early exercise intervention, encouraging physical activity, and keeping track of individualised PA that could be added to the feedback rehabilitation care plan. Citation Format: Nur Amalina Che Bakri, Richard Kwasnicki, Luqman Tenang, Emmanuel Giannas, Kieran Dhillon, Ara Darzi, Daniel Leff. Objective Comparison of Post-operative Activity after Sentinel Lymph Node Biopsy versus Axillary Lymph Node Dissection Using Wearable Activity Monitors – The ‘BRACELET’ Study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-08-11.