Factors influencing the number of sentinel lymph nodes identified in patients with breast cancer

Decreased Survival of Invasive Ductal Breast Cancer Patients With Two Macrometastatic Lymph Nodes Among Few Resected Ones: Should Current Sentinel-Lymph-Node Guidelines Be Revised?

Purpose

Sentinel-lymph-node (SLN) biopsy (SLB) is an efficient and safe axillary surgical approach with decreased morbidity than total axillary lymph node dissection (ALND) in initial patients (T1–T2). Current guidelines strongly suggest avoiding completion of ALND in patients with one or two positive SLNs that will be submitted to whole-breast radiation therapy, but must be done when three SLNs are affected.

Methods

We performed a SEER-based study with breast invasive ductal carcinoma patients treated between 2010 and 2015. Optimal cutoffs of positive LNs predictive of survival were obtained with ROC curves and survival as a continuous variable. Bias was reduced through propensity score matching. Cox regression was employed to estimate prognosis. Nomograms were constructed to analyze the predictive value of clinicopathological factors for axillary burden.

Results

Of 43,239 initial patients that had one to three analyzed LNs, only 425 had two positive LNs and matched analysis demonstrated no survival difference versus pN2 patients [HR: 0.960 (0.635–1.452), p = 0.846]. The positive-to-analyzed LN proportion demonstrated a strong prognostic factor for a low rate (1 positive to ≤1.5 analyzed) [HR = 1.567 (1.156–2.126), p = 0.004], and analysis derived from the results demonstrated that a “negative LN margin” improves survival. Nomograms shows that tumor size is the main factor of axillary burden.

Conclusion

Macrometastasis of two LNs is a poor prognostic factor, similar to pN2, in SLNB (-like) patients; more extensive studies including preconized therapies must be done in order to corroborate or refute the resistance of this prognostic difference in patients with two macrometastatic lymph nodes within few resected.

Number of nodes in sentinel lymph node biopsy for breast cancer: Are surgeons still biased?

BACKGROUND AND OBJECTIVES

The purpose of this study was to assess the number of lymph nodes removed at SLNB, and what factors might bias a surgeon's decision to remove additional nodes.

METHODS

A prospectively maintained database was reviewed. All patients that had SLNB for primary treatment of breast cancer between January 2012 and March 2016 were identified. Clinicopathologic factors were used to compare the number of LNs and rates of node positivity.

RESULTS

One thousand six hundred and three patients were included. The average number of SLNs, non-SLNs, and total LNs was 2.53, 0.54, 3.08, respectively. Significantly more LNs were removed in age <40 versus age >40 (3.73, 3.04 P < 0.01), invasive versus DCIS (3.13, 2.73 P < 0.001), Grade III versus Grade II (3.42, 2.99 P < 0.01), T2 versus T1 (3.40, 2.96 P < 0.01), and ER- versus ER+ (3.45, 3.05 P < 0.05). SLN positivity was significantly higher (P < 0.05) in invasive versus DCIS (27%, 4%), T2 versus T1 (30%. 17%), Grade II versus Grade I (42%, 18%), and ILC versus IDC (38%, 26%).

CONCLUSIONS

There was a significant difference in the number of lymph nodes removed at SLNB in certain groups however; node positivity was not necessarily higher in these groups. Surgeons must be cognizant of potential bias when performing SLNB.

Do the ACOSOG Z0011 Criteria Affect the Number of Sentinel Lymph Nodes Removed?

INTRODUCTION

We sought to determine if adoption of the Z0011 criteria was associated with removal of more sentinel lymph nodes (SLNs).

METHODS

In a retrospective review of a prospective database of breast cancer patients treated at our institution from 2006 to 2013, we identified 5213 eligible patients who elected to undergo breast-conserving surgery; 2372 were treated pre-Z0011 and 2841 post-Z0011. Clinicopathologic factors were collected, and univariate and multivariate models were fit to identify variables associated with number of SLNs removed.

RESULTS

Median patient age, 60 years, did not differ between groups. Median tumor size was similar in both groups: 1.1 (0.05-5.0) cm in the pre-Z0011 group and 1.2 (0.1-5.2) cm in the post-Z0011 group. The mean number of SLNs excised in the pre-Z0011 patients was 2.8 compared with 2.9 in post-Z0011 patients (p = 0.01). Three or fewer lymph nodes were removed in 1771 (75 %) pre-Z0011 patients compared with 2006 (71 %) post-Z0011 patients (p = 0.01). Factors associated with the removal of more SLNs on multivariate analysis included adoption of ACOSOG Z0011 criteria (p = 0.03), young age (p ≤ 0.0001), and large tumor size (p = 0.0005). Axillary lymph node dissection (ALND) was performed in 379 (16 %) patients pre-Z0011 compared with 68 (2 %) node-positive post-Z0011 patients (p < 0.0001).

CONCLUSIONS

Since the adoption of Z0011 criteria, we found significantly fewer patients undergoing ALND for positive SLNs. We noted a significant, slight shift in the removal of ≥4 SLNs. The Z0011 criteria were not associated with a clinically significant increase in the number of SLNs removed.

Comparison of [(99m)Tc]tilmanocept and filtered [(99m)Tc]sulfur colloid for identification of SLNs in breast cancer patients

Background

The efficacy of sentinel lymph node (SLN) surgery requires targeted removal of first-draining nodes; however, frequently more nodes are removed than necessary. [^99mTc]tilmanocept (TcTM) is a molecular-targeted radiopharmaceutical specifically designed for SLN mapping. We evaluated technical outcomes of SLN biopsy in breast cancer patients mapped with TcTM + vital blue dye (VBD) versus filtered [^99mTc]sulfur colloid (fTcSC) + VBD.

Methods

There were 84 versus 115 patients in the TcTM versus fTcSC cohorts, respectively. Main measures were the number of SLNs removed per patient and factors influencing number of nodes removed. We also evaluated whether the radiotracer injected affected the proportion of positive nodes removed in node-positive patients.

Results

Fewer nodes were removed among patients mapped with TcTM compared to fTcSC (mean TcTM: 1.85 vs. fTcSC: 3.24, p < 0.001). Logistic regression analysis adjusted for tumor characteristics showed that injection of fTcSC (p < 0.001) independently predicted removal of greater than 3 nodes. A similar proportion of patients was identified as node-positive, whether mapped with TcTM or with fTcSC (TcTM: 24 % vs. fTcSC: 17 %, p = 0.3); however, TcTM detected a greater proportion of positive nodes among node-positive patients compared with fTcSC (0.73 vs. 0.43, p = 0.001).

Conclusions

Patients undergoing SLN biopsy with TcTM required fewer SLNs to identify the same rate of node-positive patients compared with fTcSC in breast cancer patients with similar risk of axillary metastatic disease. These data suggest that a molecularly targeted mechanism of SLN identification may reduce the total number of nodes necessary for accurate axillary staging.

Assessing second echelon lymph nodes during sentinel lymph node biopsy: can we have more accurate axillary treatment for breast cancer patients?

Sentinel lymph node biopsy (SLNB) is the standard treatment for breast cancer patients with clinically negative axilla. For patients with positive sentinel lymph nodes, axillary lymph node dissection (ALND) was required. However, approximately a half of the SLNs-positive patients were found to have clear axillary lymph nodes after ALND, indicating that they had received unnecessary ALND without therapeutic benefit. Therefore, we propose a hypothesis for solution of this clinical problem. We defined the second echelon lymph nodes (SELNs) as those nodes receiving lymphatic drainage directly from the SLNs. For patients with positive-SLNs, SELNs can be biopsy and assessed. If SELNs are negative, no more ALND was needed in these patients even if their SLNs are positive. If our hypothesis were confirmed to be true, we can tailored our axillary treatment to more breast cancer patients, avoiding unnecessary ALND and its complications.

Sentinel node biopsy for breast cancer patients: issues for discussion and our practice

Sentinel node biopsy has been established for several years now as a standard procedure of breast cancer surgery, but there are several variations of the indications and the technique used. This paper provides information regarding several issues of debate for its application as are the selection criteria, the application to patients with multifocal/multicentric breast cancer or DCIS, postneoadjuvant chemotherapy, the necessary number of nodes to be biopsied, the need for lymphoscintigraphy, the technique for frozen section, the factors that may predict nonsentinel nodes (NSNs) involvement, the value of micrometastasis and isolated tumour cells, the internal mammary chain sentinel nodes, and finally the axillary recurrence after SLNB. Our view for these issues is included together with our experience of 430 SLNBs.

Optimal number of radioactive sentinel lymph nodes to remove for accurate axillary staging of breast cancer

BACKGROUND

Although sentinel lymph node (SLN) biopsy is the standard technique for staging the axilla of clinically node-negative breast cancer, the optimal number of radioactive SLNs to remove to ensure accuracy and minimize morbidity is still actively debated. The purpose of this study was to determine the minimum number of SLNs to excise to ensure accurate axillary staging of SLN-positive patients.

METHODS

A total of 126 patients with invasive breast cancer underwent SLN biopsy by periareolar injection of radiolabeled technetium sulfur colloid on the day of surgery. The sequence in which SLNs were removed and the corresponding ex vivo radioactive counts were recorded. SLNs were removed until radioactive counts in the axilla were less than 10% of the ex vivo counts of the hottest SLN.

RESULTS

A radioactive SLN was identified in every patient. The mean number of SLNs identified was 2.86 (range, 1-8). Clinicopathologic features associated with a positive SLN included a palpable tumor (P = .0035), increasing tumor size (P = .0039), increasing histologic grade (P = .0234), and angiolymphatic invasion (P < .001). The highest radioactive counts were found in the first node in 100 patients (79.4%), the second node in 15 (11.9%), and the third or later node in 11 patients (8.7%). Among the 38 patients with a positive SLN (30.2%), the hottest node was the first positive SLN in 27 patients (71.1%). The first positive SLN was the first node removed in 31 patients (81.6%) and after the second node in 37 patients (97.4%); it was removed in all patients by the third SLN.

CONCLUSION

These data support the trend of limiting SLN biopsy to 3 lymph nodes. Removing all SLNs with radioactive counts greater than 10% of the ex vivo counts of the hottest SLN did not increase accuracy.