MRI radiomics and biological correlations for predicting axillary lymph node burden in early-stage breast cancer.

BACKGROUND AND AIMS: Preoperative prediction of axillary lymph node (ALN) burden in patients with early-stage breast cancer is pivotal for individualised treatment. This study aimed to develop a MRI radiomics model for evaluating the ALN burden in early-stage breast cancer and to provide biological interpretability to predictions by integrating radiogenomic data. METHODS: This study retrospectively analyzed 1211 patients with early-stage breast cancer from four centers, supplemented by data from The Cancer Imaging Archive (TCIA) and Duke University (DUKE). MRI radiomic features were extracted from dynamic contrast-enhanced MRI images and an ALN burden-related radscore was constructed by the backpropagation neural network algorithm. Clinical and combined models were developed, integrating ALN-related clinical variables and radscore. The Kaplan-Meier curve and log-rank test were used to assess the prognostic differences between the predicted high- and low-ALN burden groups in both Center I and DUKE cohorts. Gene set enrichment and immune infiltration analyses based on transcriptomic TCIA and TCIA Breast Cancer dataset were used to investigate the biological significance of the ALN-related radscore. RESULTS: The MRI radiomics model demonstrated an area under the curve of 0.781-0.809 in three validation cohorts. The predicted high-risk population demonstrated a poorer prognosis (log-rank P < .05 in both cohorts). Radiogenomic analysis revealed migration pathway upregulation and cell differentiation pathway downregulation in the high radscore groups. Immune infiltration analysis confirmed the ability of radiological features to reflect the heterogeneity of the tumor microenvironment. CONCLUSIONS: The MRI radiomics model effectively predicted the ALN burden and prognosis of early-stage breast cancer. Moreover, radiogenomic analysis revealed key cellular and immune patterns associated with the radscore.

A 53-Year-Old Woman with Axillary Lymphadenopathy.

AbstractMorning Report is a time-honored tradition where physicians-in-training present cases to their colleagues and clinical experts to collaboratively examine an interesting patient presentation. The Morning Report section seeks to carry on this tradition by presenting a patient's chief concern and story, inviting the reader to develop a differential diagnosis and discover the diagnosis alongside the authors of the case. This report examines the story of a 53-year-old woman with a history of breast cancer who presented with abnormal axillary lymph nodes detected on surveillance imaging. Using history, physical examination, and diagnostic workup, an illness script for her presentation emerges. A differential diagnosis is developed and refined until a final diagnosis is confirmed.

Correlation between sentinel lymph node biopsy and non-sentinel lymph node metastasis in patients with cN0 breast carcinoma: comparison of invasive ductal carcinoma and invasive lobular carcinoma.

BACKGROUND: Some studies have suggested that axillary lymph node dissection (ALND) can be avoided in women with cN0 breast cancer with 1-2 positive sentinel nodes (SLNs). However, these studies included only a few patients with invasive lobular carcinoma (ILC), so the validity of omitting ALDN in these patients remains controversial. This study compared the frequency of non-sentinel lymph nodes (non-SLNs) metastases in ILC and invasive ductal carcinoma (IDC). MATERIALS METHODS: Data relating to a total of 2583 patients with infiltrating breast carcinoma operated at our institution between 2012 and 2023 were retrospectively analyzed: 2242 (86.8%) with IDC and 341 (13.2%) with ILC. We compared the incidence of metastasis to SLNs and non-SLNs between the ILC and IDC cohorts and examined factors that influenced non-SLNs metastasis. RESULTS: SLN biopsies were performed in 315 patients with ILC and 2018 patients with IDC. Metastases to the SLNs were found in 78/315 (24.8%) patients with ILC and in 460 (22.8%) patients with IDC (p = 0.31). The incidence of metastases to non-SLNs was significantly higher (p = 0.02) in ILC (52/78-66.7%) compared to IDC (207/460 - 45%). Multivariate analysis showed that ILC was the most influential predictive factor in predicting the presence of metastasis to non-SLNs. CONCLUSIONS: ILC cases have more non-SLNs metastases than IDC cases in SLN-positive patients. The ILC is essential for predicting non-SLN positivity in macro-metastases in the SLN. The option of omitting ALND in patients with ILC with 1-2 positive SLNs still requires further investigation.

De-escalation of axillary treatment in the event of a positive sentinel lymph node biopsy in cT1-2 N0 breast cancer treated with mastectomy: nationwide registry study (BOOG 2013-07).

BACKGROUND: Trials have demonstrated the safety of omitting completion axillary lymph node dissection in patients with cT1-2 N0 breast cancer operated with breast-conserving surgery who have limited metastatic burden in the sentinel lymph node. The aim of this registry study was to provide insight into the oncological safety of omitting completion axillary treatment in patients operated with mastectomy who have limited-volume sentinel lymph node metastasis. METHODS: Women diagnosed in 2013-2014 with unilateral cT1-2 N0 breast cancer treated with mastectomy, with one to three sentinel lymph node metastases (pN1mi-pN1a), were identified from the Netherlands Cancer Registry, and classified by axillary treatment: no completion axillary treatment, completion axillary lymph node dissection, regional radiotherapy, or completion axillary lymph node dissection followed by regional radiotherapy. The primary endpoint was 5-year regional recurrence rate. Secondary endpoints included recurrence-free interval and overall survival, among others. RESULTS: In total, 1090 patients were included (no completion axillary treatment, 219 (20.1%); completion axillary lymph node dissection, 437 (40.1%); regional radiotherapy, 327 (30.0%); completion axillary lymph node dissection and regional radiotherapy, 107 (9.8%)). Patients in the group without completion axillary treatment had more favourable tumour characteristics and were older. The overall 5-year regional recurrence rate was 1.3%, and did not differ significantly between the groups. The recurrence-free interval was also comparable among groups. The group of patients who did not undergo completion axillary treatment had statistically significantly worse 5-year overall survival, owing to a higher percentage of non-cancer deaths. CONCLUSION: In this registry study of patients with cT1-2 N0 breast cancer treated with mastectomy, with low-volume sentinel lymph node metastasis, the 5-year regional recurrence rate was low and comparable between patients with and without completion axillary treatment.

Comparison of the effect of ultrasounic-harmonic scalpel and electrocautery in the treatment of axillary lymph nodes during radical surgery for breast cancer.

OBJECTIVE: To compare the efficacy of ultrasounic-harmonic scalpel and electrocautery in the treatment of axillary lymph nodes during radical surgery for breast cancer. METHODS: A prospective study was conducted in the Department of Breast Surgery, Zhongda Hospital Affiliated to Southeast University. A total of 128 patients with pathologically confirmed breast cancer who were treated by the same surgeon from July 2023 to November 2023 were included in the analysis. All breast operations were performed using electrocautery, and surgical instruments for axillary lymph nodes were divided into ultrasounic-harmonic scalpel group and electrocautery group using a random number table. According to the extent of lymph node surgery, it was divided into four groups: sentinel lymph node biopsy, lymph node at station I, lymph node at station I and II, and lymph node dissection at station I, II and III. Under the premise of controlling variables such as BMI, age and neoadjuvant chemotherapy, the effects of ultrasounic-harmonic scalpel and electrocautery in axillary surgery were compared. RESULTS: Compared with the electrosurgical group, there were no significant differences in lymph node operation time, intraoperative blood loss, postoperative axillary drainage volume, axillary drainage tube indwelling time, postoperative pain score on the day after surgery, and the incidence of postoperative complications (p>0.05). CONCLUSION: There is no significant difference between ultrasounic-harmonic scalpel and electrocautery in axillary lymph node treatment for breast cancer patients, which can provide a basis for the selection of surgical energy instruments.

Anatomical variants of the intercostobrachial nerve and its preservation during surgery, a systematic review and meta-analysis.

BACKGROUND: The anatomic variants of the intercostobrachial nerve (ICBN) represent a potential risk of injuries during surgical procedure such as axillary lymph node dissection and sentinel lymph node biopsy in breast cancer and melanoma patients. The aim of this systematic review and meta-analysis was to investigate the different origins and branching patterns of the intercostobrachial nerve also providing an analysis of the prevalence, through the analysis of the literature available up to September 2023. MATERIALS AND METHODS: The protocol for this study was registered on PROSPERO (ID: CRD42023447932), an international prospective database for reviews. The PRISMA guideline was respected throughout the meta-analysis. A systematic literature search was performed using PubMed, Scopus and Web of Science. A search was performed in grey literature through google. RESULTS: We included a total of 23 articles (1,883 patients). The prevalence of the ICBN in the axillae was 98.94%. No significant differences in prevalence were observed during the analysis of geographic subgroups or by study type (cadaveric dissections and in intraoperative dissections). Only five studies of the 23 studies reported prevalence of less than 100%. Overall, the PPE was 99.2% with 95% Cis of 98.5% and 99.7%. As expected from the near constant variance estimates, the heterogeneity was low, I2 = 44.3% (95% CI 8.9%-65.9%), Q = 39.48, p = .012. When disaggregated by evaluation type, the difference in PPEs between evaluation types was negligible. For cadaveric dissection, the PPE was 99.7% (95% CI 99.1%-100.0%) compared to 99.0% (95% CI 98.1%-99.7%). CONCLUSIONS: The prevalence of ICBN variants was very high. The dissection of the ICBN during axillary lymph-node harvesting, increases the risk of sensory disturbance. The preservation of the ICBN does not modify the oncological radicality in axillary dissection for patients with cutaneous metastatic melanoma or breast cancer. Therefore, we recommend to operate on these patients in high volume center to reduce post-procedural pain and paresthesia associated with a lack of ICBN variants recognition.

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.

Use of axillary ultrasound to guide breast cancer management in the genomic assay era.

INTRODUCTION: Chemotherapy is conventionally offered to non-stage IV breast cancer patients with metastatic nodes. However, the RxPONDER trial showed that chemotherapy can be omitted in selected patients with 1-3 metastatic nodes if the 21-gene assay recurrence score is ≤25. We aimed to investigate if axillary ultrasound can identify this group of patients with limited nodal burden so that they can undergo upfront surgery followed by gene assay testing, to potentially avoid chemotherapy. METHODS: T1-3, node positive, hormone receptor-positive and HER2-negative breast cancer patients ≥50 years old with axillary lymph node dissection (ALND) were reviewed from 2 centres. Patients with neoadjuvant chemotherapy and bilateral cancers were excluded. Number of ultrasound-detected abnormal axillary nodes, demographic and histological parameters were correlated with the number of metastatic nodes found on ALND. RESULTS: 138 patients were included, 59 (42.8%) and 79 (57.2%) patients had 1-3 and >3 metastatic nodes on ALND respectively. On logistic regression and ROC analysis, the number of ultrasound-detected abnormal nodes was significant (p < 0.001) for predicting limited nodal burden (ROC AUC = 0.7135). Probabilities of <4 metastatic nodes with ultrasound cut-offs of 5, 6 and 8 abnormal nodes were 0.057, 0.026 and 0.005 respectively, with 100% specificity. CONCLUSION: A cut-off of ≤5 ultrasound-detected abnormal nodes can distinguish between patients with limited versus high nodal burden, with high specificity. Hence, incorporating the number of abnormal ultrasound-detected nodes into clinical practice may prove useful in guiding between upfront surgery and gene assay testing or neoadjuvant chemotherapy in this group of patients.

Surgical treatment of breast cancer.

Surgical treatment of breast cancer has changed towards less invasive procedures as summarised in this review. Breast conserving surgery (BCS) and radiotherapy (RT) are now recommended as standard of care. Several flexible marking methods for removal of non-palpable tumours have gradually replaced wire-guided localisation. Neoadjuvant systemic treatment increases tumour shrinkage and BCS and may lead to omission of axillary clearance (AC). The prognostic significance of AC in patients with metastases to 1-2 sentinel nodes at primary surgery is questioned. Results from the SENOMAC trial are expected to change guidelines from AC to axillary RT.

Axillary ultrasonography for early-stage invasive breast cancer.

BACKGROUND: Among women with early invasive breast cancer and 1-2 positive sentinel nodes, sentinel lymph node biopsy (SLNB) is non-inferior to axillary lymph node dissection (ALND).1-3 However, preoperative axillary ultrasonography (AxUS) may not be sensitive enough to discriminate burden of nodal metastasis in these patients, potentially leading to overtreatment.4-6 This study compares axillary operation rates in patients who did and did not receive preoperative AxUS, assessing its utility and risks for overtreatment. METHODS: This is a retrospective cohort study of patients with clinical T1/T2 breast tumors who were clinically node negative and underwent an axillary operation. RESULTS: Patients who had preoperative AxUS received more ALND compared to patients who did not (5.6% vs. 1.4%, p â€‹< â€‹0.001). There was no significant difference in the number of additional axillary operations following SLNB (2.1% vs. 2.3%, p â€‹= â€‹0.77). CONCLUSION: Eliminating preoperative AxUS is associated with fewer invasive ALND procedures, without increased rate of axillary reoperations.

Clipping a Positive Lymph Node Improves Accuracy of Nodal Staging After Neoadjuvant Chemotherapy for Breast Cancer Patients, but Does It Drive Management Changes?

BACKGROUND: Sentinel lymph node (SLN) biopsy for cN+ breast cancer patients after neoadjuvant chemotherapy (NAC) is controversial because the false-negative rate (FNR) is high. Identification of three or more SLNs with a dual tracer improves these results, and inclusion of a clipped lymph node (CLN) (targeted axillary dissection [TAD]) may be even more effective. METHODS: A retrospective, single-institution analysis of consecutive cN+ patients undergoing NAC from 2019 to 2021 was performed. Patients routinely underwent placement of a clip in the positive lymph node before NAC, and TAD was performed after completion of therapy. RESULTS: The study analyzed 73 patients, and the identification rate for CLN was 98.6% (72/73). A complete response in the lymph nodes was achieved for 43 (59%) of the 73 patients. Overall, the CLN was not a SLN in 18 (25%) of 73 cases, and for women who had one or two and those who had three or more SLNs identified, this occurred in 11 (32%) and 7 (21%) of 34 cases, respectively. Failure of SLN or TAD to identify a positive residual lymph node status after NAC occurred in 10 (15%) of 69 and 2 (3%) of 73 cases, respectively (p = 0.01). In four cases, a SLN was not retrieved (5.5%), and two of these cases had a positive CLN. In three cases, the CLN was the only positive node and did not match with a SLN, directing lymphadenectomy and oncologic management change in two cases. Therefore, 7 (10%) of 73 cases had a change in surgical or oncologic management with TAD. CONCLUSIONS: For a conservative axillary treatment in this setting, TAD is an effective method. It is more accurate than SLN alone and allows management changes. Further studies are warranted.

Evaluation of traditional targeted axillary dissection eligibility criteria for node-positive breast cancer after neoadjuvant chemotherapy in a prospective multicenter registry.

INTRODUCTION: Targeted axillary dissection (TAD) is performed after neoadjuvant systemic therapy (NST) to decrease the rate of non-therapeutic axillary dissection (ALND) for patients with node-positive breast cancer. In order to ensure the oncologic safety of TAD, eligibility criteria resulting in a low false negative rate (FNR) have been proposed. The purpose of this study was to evaluate the utility of the traditional criteria. METHODS: Data was collected from a prospective multicenter registry. In order to ascertain FNRs, pathologic findings in the sentinel lymph nodes (LN)s, malignant clipped LN, and axillary contents were determined. The FNRs within TAD eligibility criterion groups were compared. RESULTS: A total of 110 patients underwent TAD and ALND, and were therefore eligible for analysis. TAD retained a low FNR in advanced clinical T-N stage compared with earlier disease (T stage: 95% CI 0.00-11.93, p = 0.42; N stage: 95% CI 0.00-8.76, p = 0.31). Presentation with ≥4 abnormal LNs on axillary ultrasound did not predict a high TAD FNR (95% CI 0.00-5.37, p = 0.16). No significant differences were noted in TAD FNR when single was compared with dual tracer (blue dye vs dual tracer 95% CI 0.72-52.49, p = 0.13; radiotracer vs dual tracer 0.04-20.11, p = 0.51). Excision of the clipped LN and only one SLN was as accurate as excision of the clipped LN and ≥2 SLNs (95% CI 0.00-10.61, p = 0.38). CONCLUSIONS: TAD retained a low FNR among patients traditionally considered ineligible for this technique. However, excision of the clipped LN and at least one SLN remained essential to a low FNR.

An ultrasound-based nomogram for predicting axillary node pathologic complete response after neoadjuvant chemotherapy in breast cancer: Modeling and external validation.

INTRODUCTION: The staging and treatment of axillary nodes in breast cancer have become a focus of research. For breast cancer patients with fine-needle aspiration-or core needle biopsy-confirmed positive nodes, axillary lymph node dissection (ALND) after neoadjuvant chemotherapy (NAC) is still a standard treatment. However, some patients achieve an axillary pathologic complete response (pCR) after NAC. In this study, the authors sought to construct a model to predict axillary pCR in patients with positive axillary lymph nodes (cN+) breast cancer. METHODS: Data from patients with pathologically proven cN+ breast cancer treated with NAC followed by ALND between January 2010 and April 2019 at the Peking University Cancer Hospital were reviewed. Axillary lymph node status was assessed using ultrasonography before and after NAC. The patient cohort was assigned to the construction and internal validation cohorts according to admission time. A nomogram was constructed based on the significant factors associated with axillary pCR. The predictive performance of the model was externally validated using data from Peking University First Hospital. RESULTS: This study included 953 and 267 patients from Peking University Cancer Hospital and Peking University First Hospital, respectively. In the construction cohort, 39.7% (238 of 600) of patients achieved axillary pCR after NAC. The result of multivariate logistic regression analysis showed that tumor grade, clinical nodal response, NAC regimen, tumor pCR, lymphovascular invasion, and tumor biologic subtype were significant independent predictors of ypN0 (p < 0.05). The areas under the receiver operating characteristic curves for the construction, validation, and independent testing cohorts were 0.87 (95% confidence interval [CI], 0.84-0.90), 0.83 (95% CI, 0.79-0.87), and 0.84 (0.79-0.89), respectively. CONCLUSIONS: A nomogram was constructed to predict the pCR of axillary lymph nodes after NAC for breast cancer. Validation of both the internal and external cohorts achieved good predictive performance, indicating that the model has preliminary clinical application prospects.

Primary breast sarcomas: A 13 case-series study treated in university hospital in central Tunisia over a 25-year period.

AIM: To retrospectively study the therapeutic modalities of primary breast sarcomas in view of the data of a local Tunisian experience. METHODS: It is a monocentric, descriptive, retrospective study including 13 cases of primary breast sarcoma treated over a period of 25 years (1995-2020) in the oncological radiotherapy department of a university hospital in Sousse, Tunisia. RESULTS: In our study, 13 cases of non-metastatic breast sarcomas that has been identified, divided into ten cases of phyllodes sarcomas and three cases of non-phyllodes sarcomas.Surgically, all our patients had a mastectomy. Among them, seven underwent a lymph node procedure: five underwent axillary lymph node dissection, and two others had primary axillary lymph node biopsy. For the adjuvant treatment, all the patients included in our study received radiotherapy and seven received chemotherapy. Local recurrence occurred on the operative scar in one patient after completion of radiation therapy. Metastatic relapse was described in five patients. The time to onset of metastases varied between two months and five years. Nevertheless, a complete remission was noted in 6 patients with a follow-up varying from four years to 20 years. Two patients were lost to follow-up. CONCLUSION: Breast sarcomas remain a very rare entity of aggressive tumors.The therapeutic approach is poorly codified. For this reason, the therapeutic decision should always be discussed in a multidisciplinary assessment.

[Preventive axillary lymphovenous anastomoses simultaneously with lymph node dissection in the treatment of breast cancer for prevention of lymphedema of the upper limb (LYMPHA technique)]. / Preventivnoe nalozhenie limfovenoznykh anastomozov v podmyshechnoi oblasti odnomomentno s limfaticheskoi dissektsiei pri lechenii raka molochnoi zhelezy dlya profilaktiki limfedemy verkhnei konechnosti (metodika LYMPHA).

OBJECTIVE: To analyze the effect the LYMPHA technique on the incidence of upper limb lymphedema in patients with breast cancer after complete axillary lymph node dissection. MATERIAL AND METHODS: There were 89 patients with breast cancer and signs of metastatic lesion of axillary lymph nodes who underwent complete axillary lymph dissection. In group 1 (41 patients), the LYMPHA technique was used simultaneously with lymph node dissection; in group 2 (48 patients) - lymph node dissection alone. RESULTS: The follow-up period was 1 year. The LYMPHA technique prolonged surgery and decreased duration of postoperative lymphorrhea. The incidence of upper limb lymphedema was 9.8% and 22.9%, respectively. CONCLUSION: The LYMPHA technique was effective for prevention of upper limb lymphedema after complete axillary lymph node dissection in the treatment of breast cancer.

Understanding Treatment Decision-Making in Older Women With Breast Cancer: A Survey-Based Study.

INTRODUCTION: For women ≥70 y old with early-stage hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer, the national guidelines recommend the omission of sentinel lymph node biopsy (SLNB) and post-lumpectomy radiotherapy. However, national-level data suggest these treatments remain common. We utilized a survey-based approach to explore patient-level factors driving overutilization. METHODS: We recruited women ≥70 y old with early-stage hormone receptor-positive/human epidermal growth factor receptor 2-negative breast cancer within 6 mo of surgery. An exploratory cross-sectional survey captured information on offered and pursued treatments, the importance of patient-centered outcomes, and the influence of each outcome on treatment decision-making. Descriptive statistics were used for analysis. RESULTS: 31/51 patients completed the survey with a response rate of 61%. Most patients (86%) received a lumpectomy. Twenty-eight percent of patients received SLNB, and 56% of lumpectomy patients underwent adjuvant radiotherapy. When considering treatment options, the patient-centered outcomes, most important for decision-making, were overall survival, breast-specific survival, and preventing local recurrence, while breast appearance, financial costs, and avoiding the need for pills (endocrine therapy) were the least important. CONCLUSIONS: Patients' treatment decisions align with their values. The correlation between patient-stated values and treatment decisions suggests a perceived mortality benefit of low-value SLNB and radiotherapy. These findings can inform targeted efforts to deimplement low-value care in breast cancer through patient-focused tools and education.

Anatomy Versus Biology: What Guides Chemotherapy Decisions in Older Patients With Breast Cancer?

INTRODUCTION: With the increasing utilization of genomic assays, such as the Oncotype DX recurrence score (RS), the relevance of anatomic staging has been questioned for select older patients with breast cancer. We sought to evaluate differences in chemotherapy receipt and/or survival among older patients based on RS and sentinel lymph node biopsy (SLNB) receipt/result. METHODS: Patients aged ≥ 65 diagnosed with pT1-2/cN0/M0 hormone-receptor-positive (HR+)/HER2-breast cancer (2010-2019) were selected from the National Cancer Database. Logistic regression was used to identify factors associated with chemotherapy receipt. Cox proportional hazards models were used to estimate the association of RS/SLNB group with overall survival. A cost-benefit study was also performed. RESULTS: Of the 75,428 patients included, the majority had an intermediate RS (58.2% versus 27.9% low, 13.8% high) and were SLNB- (85.1% versus 11.6% SLNB+, 3.3% none). Chemotherapy was recommended for 13,442 patients (17.8%). After adjustment, chemotherapy receipt was more likely with higher RS and SLNB+. After adjustment, SLNB receipt/result was only associated with overall survival among those with an intermediate RS. However, returning to the OR for SLNB is not cost-effective. CONCLUSIONS: SLNB receipt/result was associated with survival for those with an intermediate RS, but not a low or high RS, suggesting that an SLNB may indeed be unnecessary for select older patients with breast cancer.