Breast cancer sentinel node identification and classification after neoadjuvant chemotherapy-systematic review and meta analysis

Sentinel lymph node biopsy before and after neoadjuvant chemotherapy in cN0 breast cancer patients: impact on axillary morbidity and survival-a propensity score cohort study

PURPOSE

In patients with clinically lymph node-negative (cN0) breast cancer, performing sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NACT) has been preferentially embraced in comparison to before NACT. However, survival outcomes associated with both strategies remain understudied. We aimed to compare the axillary lymphadenectomy (ALND) rate, disease-free survival (DFS), and overall survival (OS), between two strategies.

METHODS

We included 310 patients in a retrospective observational study. SNLB was performed before NACT from December 2006 to April 2014 (107 cases) and after NACT from May 2014 to May 2020 (203 patients). An inverse probability of treatment weighting (IPTW) method was applied to homogenize both groups. Hazard ratios (HR) and odd ratios (OR) are reported with 95% confidence intervals (95%CI).

RESULTS

The lymphadenectomy rate was 29.9% before NACT and 7.4% after NACT (p < 0.001), with an OR of 5.35 95%CI (2.7-10.4); p = .002. After 4 years of follow-up, SLNB after NACT was associated with lower risk for DFS, HR 0.42 95%CI (0.17-1.06); p = 0.066 and better OS, HR 0.21 CI 95% (0.07-0.67); p = 0.009 than SLNB before NACT. After multivariate analysis, independent adverse prognostic factors for OS included SLNB before NACT, HR 3.095 95%CI (2.323-4.123), clinical nonresponse to NACT, HR 1.702 95% CI (1.012-2.861), and small tumors (cT1) with high proliferation index, HR 1.889 95% (1.195-2.985).

CONCLUSION

Performing SLNB before NACT results in more ALND and has no benefit for patient survival. These findings support discontinuing the practice of SLNB before NACT in patients with cN0 breast cancer.

The use of blue dye alone for sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with initially node-positive breast cancer

INTRODUCTION

False-negative sentinel lymph node biopsy (SLNB) rates following neoadjuvant chemotherapy (NACT) in initially node-positive (cN1/2) breast cancer patients are high, but decrease when lymph nodes are clipped, ≥3 sentinel lymph nodes (SLN) are removed or dual-tracer localization (radioisotope and blue dye) is used. Radiotracer, however, is often unavailable and outcomes with blue dye alone are unknown.

MATERIALS AND METHODS

Initially cT1-4, cN1/2 patients treated with NACT in 2013-2023 who underwent SLNB using blue dye alone were evaluated regarding SLN identification, axillary recurrence, disease-free and overall survival rates.

RESULTS

Of 119 patients included, 19 remained cN1/2 after NACT. SLNB was performed using blue dye alone in 100 ycN0 cases (84%), with an identification rate of 96%. The SLN was negative in 70/119 cases (i.e. 59% avoided axillary dissection). The number of SLN detected was ≥3 in 55/70 cases (78%) (median 3.1; 1-6). Median age was 49 years (25-84). Most were T2 (n = 40, 57.1%), N1 (n = 64, 91.4%). Predominant subtypes were ERBB2 (52.9%) and triple-negative (20%). No axillary recurrence occurred over a median 36-month period. Five-year disease-free and overall survival were, respectively, 85.9% (95%CI: 74-99.8) and 96.3% (95%CI: 89.4-100). The ERBB2 subtype (1.99, 95%CI: 1.02-3.85, p = 0.04) and N1 lymph node status (2.58, 95%CI: 1.54-9.10, p = 0.03) were associated with a greater likelihood of undergoing SLNB alone without axillary dissection.

CONCLUSIONS

SLNB with blue dye alone following NACT in initially cN1/2 patients avoided axillary dissection in almost 60% of cases, with no recurrences during the period evaluated. Longer follow-up studies are necessary.

Changes in Surgical Management of the Axilla Over 11 Years - Report on More Than 1500 Breast Cancer Patients Treated with Neoadjuvant Chemotherapy on the Prospective I-SPY2 Trial

BACKGROUND

Axillary surgery after neoadjuvant chemotherapy (NAC) is becoming less extensive. We evaluated the evolution of axillary surgery after NAC on the multi-institutional I-SPY2 prospective trial.

METHODS

We examined annual rates of sentinel lymph node (SLN) surgery with resection of clipped node, if present), axillary lymph node dissection (ALND), and SLN and ALND in patients enrolled in I-SPY2 from January 1, 2011 to December 31, 2021 by clinical N status at diagnosis and pathologic N status at surgery. Cochran-Armitage trend tests were calculated to evaluate patterns over time.

RESULTS

Of 1578 patients, 973 patients (61.7%) had SLN-only, 136 (8.6%) had SLN and ALND, and 469 (29.7%) had ALND-only. In the cN0 group, ALND-only decreased from 20% in 2011 to 6.25% in 2021 (p = 0.0078) and SLN-only increased from 70.0% to 87.5% (p = 0.0020). This was even more striking in patients with clinically node-positive (cN+) disease at diagnosis, where ALND-only decreased from 70.7% to 29.4% (p < 0.0001) and SLN-only significantly increased from 14.6% to 56.5% (p < 0.0001). This change was significant across subtypes (HR-/HER2-, HR+/HER2-, and HER2+). Among pathologically node-positive (pN+) patients after NAC (n = 525) ALND-only decreased from 69.0% to 39.2% (p < 0.0001) and SLN-only increased from 6.9% to 39.2% (p < 0.0001).

CONCLUSIONS

Use of ALND after NAC has significantly decreased over the past decade. This is most pronounced in cN+ disease at diagnosis with an increase in the use of SLN surgery after NAC. Additionally, in pN+ disease after NAC, there has been a decrease in use of completion ALND, a practice pattern change that precedes results from clinical trials.

Feasibility of Sentinel Lymph Node Biopsy in Breast Cancer Patients with Axillary Conversion after Neoadjuvant Chemotherapy-A Single-Tertiary Centre Experience and Review of the Literature

(1) Introduction: Sentinel lymph node biopsy (SLNB) is widely used in breast cancer patients who undergo neoadjuvant chemotherapy (NAC), replacing axillary lymph node dissection. While commonly accepted for cN0 patients, its role in cN1/2 patients remains controversial. Our study aims to investigate the role of SLNB in BC patients who underwent prior NAC and compare our results to those of other studies presented in the literature. (2) Materials and methods: Our retrospective study included 102 breast cancer patients who received NAC before 99mTc-albumin Nanocolloid SLN mapping and SLNB was performed, completed or not with axillary dissection. A review based on the PRISMA statement was also carried out, encompassing 20 studies. (3) Results: The lymphoscintigraphy performed after the administration of NAC presented an identification rate (IR) of 93.13%. IR for SLNB was 94.11%, with a false-negative rate (FNR) of 7.4%. After a median follow-up of 31.3 months, we obtained a distant disease-free survival rate of 98%. The results obtained by other groups were similar to those of our study, presenting IR in the range 80.8-96.8%, with FNR varying from 0 to 22%. (4) Conclusions: on conclusion, SLNB can accurately determine the lymph node status, with an acceptable FNR and maintain its expected prognostic role with low recurrence rates, and our results are comparable to those obtained by other studies.

Outcomes of a Multidisciplinary Team in the Management of Patients with Early-Stage Breast Cancer Undergoing Neoadjuvant Chemotherapy at a Community Cancer Center

Background: The utilization of neoadjuvant chemotherapy (NAC) remains highly variable in clinical practice. The implementation of NAC requires coordination of handoffs between a multidisciplinary team (MDT). This study aims to assess the outcomes of an MDT in the management of early-stage breast cancer patients undergoing neoadjuvant chemotherapy at a community cancer center. Methods: We conducted a retrospective case series on patients receiving NAC for early-stage operable or locally advanced breast cancer coordinated by an MDT. Outcomes of interest included the rate of downstaging of cancer in the breast and axilla, time from biopsy to NAC, time from completion of NAC to surgery, and time from surgery to radiation therapy (RT). Results: Ninety-four patients underwent NAC; 84% were White and mean age was 56.5 yrs. Of them, 87 (92.5%) had clinical stage II or III cancer, and 43 (45.8%) had positive lymph nodes. Thirty-nine patients (42.9%) were triple negative, 28 (30.8%) were human epidermal growth factor receptor (HER-2)+, and 24 (26.2%) were estrogen receptor (ER) +HER-2-. Of 91 patients, 23 (25.3%) achieved pCR; 84 patients (91.4%) had downstaging of the breast tumor, and 30 (33%) had axillary downstaging. The median time from diagnosis to NAC was 37.5 days, the time from completion of NAC to surgery was 29 days, and the time from surgery to RT was 49.5 days. Conclusions: Our MDT provided timely, coordinated, and consistent care for patients with early-stage breast cancer undergoing NAC as evidenced by time to treatment outcomes consistent with recommended national trends.

The value of sentinel lymph-node biopsy in women with node-positive breast cancer at diagnosis and node-negative tumour after neoadjuvant therapy: a systematic review

PURPOSE

To conduct a systematic review to analyse the performance of the sentinel lymph-node biopsy (SLNB) in women with node-positive breast cancer at diagnosis and node-negative tumour after neoadjuvant therapy, compared to axillary lymph-node dissection.

METHODS

The more relevant databases were searched. Main outcomes were false-negative rate (FNR), sentinel lymph-node identification rate (SLNIR), negative predictive value (NPV), and accuracy. We conducted meta-analyses when appropriate.

RESULTS

Twenty studies were included. The pooled FNR was 0.14 (95% CI 0.11-0.17), the pooled SLNIR was 0.89 (95% CI 0.86-0.92), NPV was 0.83 (95% CI 0.79-0.87), and summary accuracy was 0.92 (95% CI 0.90-0.94). SLNB performed better when more than one node was removed and double mapping was used.

CONCLUSIONS

SLNB can be performed in women with a node-negative tumour after neoadjuvant therapy. It has a better performance when used with previous marking of the affected node and with double tracer.

Estimating the Benefit of Preoperative Systemic Therapy to Reduce the Extent of Breast Cancer Surgery: Current Standard and Future Directions

Once reserved for locally advanced tumors which were deemed inoperable at presentation, preoperative systemic therapy (PST) is nowadays increasingly used to treat early breast cancer. PST allows for in vivo assessment of tumor response, for tailoring of adjuvant systemic therapy and for de-escalation of breast and the axillary surgery. Increased rates of pathological complete response together with more accurate response assessment and surgical planning have led to a significant reduction in surgical morbidity. While surgical assessment remains the standard of care, ongoing studies are evaluating whether surgery can be omitted in patients who achieve a complete pathological response. In this chapter, I will review the impact of PST on surgical de-escalation and the data supporting the safety of this approach.

ACR Appropriateness Criteria® Imaging of the Axilla

This publication reviews the current evidence supporting the imaging approach of the axilla in various scenarios with broad differential diagnosis ranging from inflammatory to malignant etiologies. Controversies on the management of axillary adenopathy results in disagreement on the appropriate axillary imaging tests. Ultrasound is often the appropriate initial imaging test in several clinical scenarios. Clinical information (such as age, physical examinations, risk factors) and concurrent complete breast evaluation with mammogram, tomosynthesis, or MRI impact the type of initial imaging test for the axilla. Several impactful clinical trials demonstrated that selected patient's population can received sentinel lymph node biopsy instead of axillary lymph node dissection with similar overall survival, and axillary lymph node dissection is a safe alternative as the nodal staging procedure for clinically node negative patients or even for some node positive patients with limited nodal tumor burden. This approach is not universally accepted, which adversely affect the type of imaging tests considered appropriate for axilla. This document is focused on the initial imaging of the axilla in various scenarios, with the understanding that concurrent or subsequent additional tests may also be performed for the breast. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

The value of sentinel lymph-node biopsy after neoadjuvant therapy: an overview

PURPOSE

We conducted a systematic review to analyse the performance of the sentinel lymph-node biopsy (SLNB) after the neoadjuvant chemotherapy, compared to axillary lymph-node dissection, in terms of false-negative rate (FNR) and sentinel lymph-node identification rate (SLNIR), sensitivity, negative predictive value (NPV), need for axillary lymph-node dissection (ALND), morbidity, preferences, and costs.

METHODS

MEDLINE, Embase, Scopus, and The Cochrane Library were searched. We assessed the quality of the included systematic reviews using AMSTAR2 tool, and estimated the degree of overlapping of the individual studies on the included reviews.

RESULTS

Six systematic reviews with variable quality were selected. We observed a very high overlapping degree across the included reviews. The FNR and the SLNIR were quite consistent (FNR 13-14%; SLNIR ~ 90% or higher). In women with initially clinically node-negative breast cancer, the FNR was better (6%), with similar SLNIR (96%). The included reviews did not consider the other prespecified outcomes.

CONCLUSIONS

It would be reasonable to suggest performing an SLNB in patients treated with NACT, adjusting the procedure to the previous marking of the affected lymph node, using double tracer, and biopsy of at least three sentinel lymph nodes. More well-designed research is needed. PROSPERO registration number: CRD42020114403.

Sentinel Lymph Node Methods in Breast Cancer

Breast cancer is the most frequent cancer diagnosed in women worldwide. Accurate lymph node staging is essential for both prognosis (of early-stage disease) and treatment (for regional control of disease) in patients with breast cancer. The sentinel lymph nodes are the regional nodes that directly drain lymph from the primary tumor. No imaging modality is accurate enough to detect lymph node metastases when a primary breast cancer is at an early stage (I or II), but sentinel lymph node biopsy is a highly reliable method for screening axillary nodes and for identifying metastatic (including micro-metastatic) disease in regional lymph nodes. Despite the widespread use of sentinel lymph node biopsy for early-stage breast cancer, relevant variations have been described regarding practical aspects of the procedure, and some variability has initially been reported regarding the rates of intraoperative sentinel lymph node identification and of false-negative findings, most likely because of differences in the size of the populations being investigated and in lymphatic mapping techniques. Nevertheless, using adequate learning curves and once a multidisciplinary team is experienced with the procedure, improved levels of accuracy are achieved.

Lymph nodal radiotherapy in breast cancer: what are the unresolved issues?

Introduction: Sentinel lymph node biopsy (SLNB) is the gold standard in invasive breast cancer. Axillary dissection (ALND) is controversial in some presentations.Areas covered: Key questions were formulated and explored focused on four different scenarios in adjuvant axillary radiation management in early and locally advanced breast cancer. Answers to these questions were searched in MEDLINE, PubMed from June 1946 to August 2020. Clinical trials, retrospective studies, international guidelines, meta-analysis, and reviews were explored.Expert opinion: Analysis according to biological disease characteristics is necessary to establish the impact of ALND avoidance in unexpectedly positive SLNB (pN1) in cN0 patients. A low-risk probability of axillary recurrence was observed if axillary radiotherapy (ART) or ALND were offered without impact on outcomes. Adjuvant RNI in pT1-3 pN1 treated with mastectomy or BCS should be proposed in unfavorable disease and risk factors. In ycN0 after NACT, SLNB can be offered in selected cases or ALND should be performed. After SLNB post-NACT (ypN1), ALND and adjuvant radiotherapy are mandatory.

Does the false-negative rate for 1 or 2 negative sentinel nodes after neo-adjuvant chemotherapy translate into a high local recurrence rate?

Prospective trials demonstrate that sentinel node (SN) biopsy after neo-adjuvant chemotherapy (NACT) has a significant false-negative rate (FNR) when only 1 or 2 SNs are removed. It is unknown whether this increased FNR correlates with an elevated risk of recurrence. Tumor Registry data at an NCI-Designated Comprehensive Cancer Center were reviewed from 2004 to 2018 for patients having a negative SN biopsy after NACT. Among 190 patients with histologically negative nodes after NACT having 1 (n = 42), 2 (n = 46), and ≥3 (n = 102) SNs, axillary recurrences occurred in 7.14%, 0%, and 1.96% (p = 0.09), breast recurrences occurred in 2.38%, 6.52%, and 0.98% (p = 0.12), and distance recurrences occurred in 16.67%, 8.70%, and 7.84% (p = 0.27), respectively. Time to first recurrence did not differ by SN count (p = 0.41). After adjustment for age, race, clinical stage, and receptor status, there were no differences in the rates of axillary (p = 0.26), breast (p = 0.44), or distance recurrence (p = 0.24) by numbers of SNs harvested. Median follow-up was 46.8 months. Despite higher post-NACT FNRs reported in randomized trials for patients having <3 sentinel nodes, recurrence rates were not significantly different for 1 versus 2 versus ≥3 SNs. This suggests that patients having 1 or 2 post-NACT SNs identified may not necessitate axillary dissection.

Less Axillary Lymphadenectomy is More Beneficial: 27-Year Follow-up of Patients with Breast Cancer

Background: One of the most important alterations in breast cancer treatment is the change of view in axillary lymph node management. At the moment, sentinel lymph node biopsy (SLNB) is the standard care in axillary lymph node management. However, in patients with clinically positive lymph nodes or in patients, who have no willingness to receive radioactive drugs, axillary lymph node dissection (ALND) must be done. To the best of our knowledge, there is no overall survival (OS) benefit in ALND, especially at the early stage of breast cancer, during which this procedure is not justified. Objectives: Herein, we have reported the results of 27 years of experiments in limited axillary lymph node dissection (LALND) in comparison to ALND as well as the relationship among the number of removed lymph nodes, OS, and disease-free survival (DFS) at the early stage of breast cancer. Methods: OS and DFS for 588 cases, who were at the early stage of breast cancer and treated by LALND between 1984 and 2019, were compared with 1026 patients, who were treated by ALND during the same interval in this study. Notably, SLNB cases were excluded. Results: The results revealed no significant difference among the groups in terms of DFS (P = 0.268, 0.123, and 0.333). Also, there was no difference in terms of OS between the LALND group (1 - 4 nodes, 5 - 6 nodes, and 7 - 8 nodes) and ALND group (≥ 9 nodes) in patients without lymph node involvement (AHR less than 2). However, in the patients with axillary lymph node metastasis (N1, N2), similar results were obtained. Correspondingly, in this group, the best results were observed in those patients, whose 7 - 8 lymph nodes were removed. Conclusions: Regarding the results of the current study; it can be concluded that performing the LALND in the defined anatomic range and removing 7 - 8 lymph nodes instead of removing 10 lymph nodes are not inferior when it is not possible to do SLNB (there is no access to it) and/or being a contraindication to do it for evaluating the status of axillary lymph nodes in the patients at the early stage of breast cancer.

Management of the axilla with sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer: A single-center study

The neoadjuvant chemotherapy (NAC) is the gold standard initial treatment of the locally advanced breast cancer (LABC). However, the reliability of methods that used to assess response the NAC is still controversial. In this study, patients with LABC who underwent NAC were evaluated retrospectively. The assessment of response to NAC and the effect of axillary approach were investigated on LABC course.The study comprised 94 patients who received NAC with an LABC diagnosis between 2008 and 2020. In our center, magnetic resonance imaging, ultrasonography, and F-flouro deoxyglucose positron emission tomography/computed tomography, and, for some patients, fine-needle aspiration biopsy of suspicious axillary lymph nodes have been performed to assess the effects of NAC. Patients with positive hormone receptor status received adjuvant hormonotherapy, and those with human epidermal growth factor receptor 2 gene expression were treated with trastuzumab. Adjuvant radiotherapy was applied to all patients undergoing breast conserving surgery. Radiotherapy was applied to the peripheral lymphatic areas in the clinical N1 to N3 cases regardless of the response to NAC.The clinical response to the NAC was found that partial in 59% and complete in 19% of the patients. However, 21.2% of the patients were unresponsive. The mean of lymph nodes that excised with the procedure of sentinel lymph node biopsy (SLNB) was 2.4 (range 1-7). In 22 of the 56 patients who underwent SLNB, axillary dissection (AD) was added to the procedure upon detection of metastasis in frozen section examinations. There was no difference between the SLNB and AD groups regarding overall survival (OS; P = .472) or disease-free survival (DFS) rates (P = .439). However, there were differences in the OS (P < .05) and DFS (P = .05) rates on the basis of the LABC histopathological subtypes.The study found that a relationship between molecular subtypes and LABC survival. However, the post-NAC axillary approach had no effect on OS or DFS. Therefore, multiple imaging and interventional methods are needed for the evaluation of NAC response. In addition, morbidity can be avoided after AD by the use of SLNB in cN0 patients.

Axillary management after neoadjuvant treatment

Since its introduction nearly 30 years ago, sentinel lymph node biopsy (SLNB) has become the standard technique to stage the axilla for the great majority of patients with early breast cancer. While the accuracy of SLNB in clinically node-negative patients who undergo neoadjuvant chemotherapy (NAC) is similar to the upfront surgery setting, modifications of the technique to improve the false negative rate are necessary in node-positive patients at presentation. Currently, patients who present with matted nodes, cN1 patients who fail to downstage to cN0 with NAC and those with pathological residual disease have an indication to undergo axillary lymph node dissection. Ongoing trials will confirm if extensive nodal irradiation can replace surgery in patients with residual nodal disease after NAC and if nodal radiotherapy can be omitted in patients who achieve nodal pathological complete response. The aim of this review was to focus on the open questions on the management of the axilla after NAC.

Role of gamma probe-assisted intraoperative sentinel lymph node evaluation in predicting axillary breast cancer metastasis after neoadjuvant chemotherapy

OBJECTIVE

Intraoperative sentinel lymph node biopsy is a universally accepted technique to identify patients who are candidates for axillary lymph node dissection during breast cancer surgery. However, there is controversy over its use in patients who underwent preoperative neoadjuvant chemotherapy. This study aimed to examine the diagnostic value of gamma probe-assisted intraoperative sentinel lymph node examination with frozen section in breast cancer patients who had undergone preoperative neoadjuvant chemotherapy.

METHODS

This retrospective study included 94 tumors diagnosed with stage IIA, IIB or IIIA invasive breast cancer with locoregional lymph node metastasis who underwent surgical treatment after neoadjuvant chemotherapy. Intraoperatively, axillary sentinel lymph node sampling was done using radioactive colloid and gamma probe and materials were examined with frozen section method. Patients with positive sentinel nodes underwent axillary resection. Histopathological examination of all surgical samples was done postoperatively.

RESULTS

In 87 of 94 tumors (92.6%), a sentinel lymph node could be identified using the method. The sensitivity, specificity and accuracy of the method for predicting axillary macro metastasis were 85.7, 86.5 and 86.2%, respectively, with 5.7% false negative rate.

CONCLUSIONS

Sentinel lymph node identification using preoperative scintigraphy and intraoperative use of gamma probe seems to be a feasible and efficient method in terms of differentiating patients that require axillary lymph node dissection during breast cancer surgery, even when they have received neoadjuvant chemotherapy. Further large prospective studies allowing subgroup analyses are warranted.

Sentinel Lymph Node Biopsy is a Reliable Method for Lymph Node Evaluation in Neoadjuvant Chemotherapy-treated Patients with Breast Cancer

Sentinel lymph node (SLN) mapping in patients with breast cancer treated with neoadjuvant chemotherapy has been debated by surgeons as a result of potential compromise of lymphatic drainage. Whether clinicopathologic variables traditionally associated with SLN positivity differ in patients who have been treated with neoadjuvant chemotherapy has not been well studied. Patients diagnosed with breast carcinoma who underwent neoadjuvant chemotherapy, definitive breast surgery, sentinel node biopsy (SNB), and axillary lymph node dissection (ALND) were retrospectively identified over a 75-month period. Clinicopathologic parameters including age, clinical tumor and node stage, neoadjuvant chemotherapy regimen, pathological tumor and node stage, lymphovascular invasion (LVI), SLN and non-SLN involvement, and extranodal extension were recorded. Ninety-seven patients met inclusion criteria. Ninety-eight per cent had successful SLN mapping. Eight patients with negative SLNs had positive ALND (false-negative rate, 8.3%). Clinicopathological variables associated with SLN status included clinical axillary status ( P = 0.038), pathologic tumor size, and nodal status and LVI ( P < 0.001). Extranodal extension was significantly associated with non-SLN status ( P = 0.004). In patients achieving a pathologic complete response (PCR), SNB remained feasible and accurate (false-negative rate, 11.6%). Successful SLN mapping in patients who have undergone neoadjuvant chemotherapy is highly accurate with a low false-negative rate even in patients who have a PCR.

Does 'fast - track' axillary node clearance following positive core biopsy lead to overtreatment of axilla?

AIMS

Sentinel lymph node biopsy (SLNB) is the preferred axillary staging procedure, although axillary node clearance (ANC) is still indicated in subgroups of patients. This study aims to review our practice of axillary treatment in node positive cancer, to determine the proportion of patients requiring ANC and to identify if this can be avoided in some patients.

METHODS

Retrospective data for all breast cancer patients who underwent surgery between 1 January 2017 and 31 December 2018 were included in this study. The histopathology results of ANC were correlated with axillary ultrasound findings, axillary biopsy or SLNB results and effect of neoadjuvant treatment. These were analysed against the available guidelines to evaluate the current practice.

RESULTS

82 patients out of 520 had ANC (15.7%). Four groups were identified: Group A included 45 patients with nodal infiltration on preoperative biopsy; Group B included 24 patients with nodal infiltration who had neoadjuvant chemotherapy (NACT); Group C included 11 patients with involved nodes on SLNB; Group D included 2 patients with axillary recurrence. 35.5% of patients in Group A had only 1-2 positive nodes following ANC. Complete pathological response was observed in 37.5% patients following NACT. No further nodes were subsequently found in a majority of patients who underwent ANC following positive SLNB (63.6%).

CONCLUSIONS

15.7% of breast cancer patients required ANC. Few patients now require ANC following positive SLNB. The practice of direct (fast-track) ANC after axillary biopsy may lead to overtreatment of the axilla, which needs re-evaluation. Targeted axillary dissection could avoid unnecessary axillary dissection in patients with abnormal nodes and in patients who have received NACT.

The Adventure of Axillary Treatment in Early Stage Breast Cancer

Axillary lymph node dissection (ALND) which was an essential part of breast cancer treatment and the gold standard in evaluation of the status of axillary lymph node had notorious with increased arm morbidity and reduction of quality of life. Sentinel lymph node biopsy (SLNB) accurately stages the axilla in early breast cancer and ALND is omitted in SLNB negative patients. In patients with positive SLNB the omission of ALND with or without replacement of axillary radiotherapy has also been recommended by guidelines. The neoadjuvant chemotherapy (NAC) which has been increasingly used for large breast cancers to downstage the tumours for allowing breast conserving surgery and decreasing mastectomy rate has also been used in axillary node positive patients to reduce the need for ALND. The issues surrounding the treatment of axilla in patients treated with NAC; application and false negative rate of SLNB, number of identified sentinel lymph nodes, and axillary radiotherapy instead of ALND are currently the discussed and practiced hot topics. The quests for decreasing arm morbidity without compromising outcome in breast cancer treatment which have begun with the invention of SLNB continue for axilla conserving surgery. This article reviews the adventure of axillary treatment in breast cancer patients treated with or without NAC.

Management of the clinically positive axilla

Axillary dissection has been the standard of care for any patient with clinically positive lymph nodes at initial breast cancer presentation. However, modern neo-adjuvant therapies can convert positive nodes to negative nodes, especially in the setting of HER2-positive disease. Accurate axillary staging can be achieved after neo-adjuvant therapy in initially node-positive patients using dual tracer lymphatic mapping, removal of three or more lymph nodes, and confirmation of excision of the previously biopsied and clipped lymph node. Currently accruing clinical trials are designed to determine which patients can safely avoid axillary dissection and/or axillary radiation.

Breast MRI and tumour biology predict axillary lymph node response to neoadjuvant chemotherapy for breast cancer

BACKGROUND

In patients who have had axillary nodal metastasis diagnosed prior to neoadjuvant chemotherapy for breast cancer, there is little consensus on how to manage the axilla subsequently. The aim of this study was to explore whether a combination of breast magnetic resonance imaging (MRI) assessed response and primary tumour pathology factors could identify a subset of patients that might be spared axillary node clearance.

METHODS

A retrospective data analysis was performed of patients with core biopsy-proven axillary nodal metastasis prior to commencement of neoadjuvant chemotherapy (NAC) who had subsequent axillary node clearance (ANC) at definitive breast surgery. Breast tumour and axillary response at MRI before, during and on completion of NAC, core biopsy tumour grade, tumour type and immunophenotype were correlated with pathological response in the breast and the number of metastatic nodes in the ANC specimens.

RESULTS

Of 87 consecutive patients with MRI at baseline, interim and after neoadjuvant chemotherapy who underwent ANC at time of breast surgery, 33 (38%) had no residual macrometastatic axillary disease, 28 (32%) had 1-2 metastatic nodes and 26 (30%) had more than 2 metastatic nodes. Factors that predicted axillary nodal complete response were MRI complete response in the breast (p < 0.0001), HER2 positivity (p = 0.02) and non-lobular tumour type (p = 0.015).

CONCLUSION

MRI assessment of breast tumour response to NAC and core biopsy factors are predictive of response in axillary nodes, and can be used to guide decision making regarding appropriate axillary surgery.

Node positive breast cancer: Concordance between baseline PET/CT and sentinel node assessment after neoadjuvant therapy

INTRODUCTION

Sentinel node biopsy for axillary staging in node positive patients after neoadjuvant treatment is controversial, mainly due to high false negative rates. We examined the concordance between the location of the hot nodes identified on PET-CT at presentation with the location of the sentinel nodes.

MATERAILS AND METHODS

Fifty-eight breast cancer patients undergoing neoadjuvant treatment between January 2013 and September 2018 who had positive regional lymph nodes on PET/CT, and a SPECT/CT lymphoscintigraphy completed before sentinel node biopsy were included. Patient, tumor and treatment characteristics were collected. Images of PET/CT were compared to images of SPECT/CT lymphoscintigraphy post treatment and concordance between location of the hot nodes on PET/CT with the sentinel nodes visualized on SPECT/CT was assessed. Association between patient, tumor and treatment characteristics and concordance between the sentinel node and the hot nodes was determined.

RESULTS

Sentinel nodes were identified in 53 (91%) of the cases in surgery. In 25 (43%) patients, axillary nodes were positive after treatment. In 16 (28%; 95% CI 18, 40) the sentinel node was not one of the hot nodes seen on PET/CT at presentation. Twenty-three (40%) patients had excision of additional axillary nodes. In two patients with non-concordant sentinel nodes, the sentinel node was falsely negative.

CONCLUSIONS

In node positive patients who undergo neoadjuvant treatment, the sentinel node visualized on lymphatic mapping is not necessarily one of the hot nodes identified on PET/CT at presentation. These findings underline the importance of marking the pathologically proven lymph node and excising it as well as the sentinel nodes after treatment.

The Sentinel Lymph Node Biopsy Using Indocyanine Green Fluorescence Plus Radioisotope Method Compared With the Radioisotope-Only Method for Breast Cancer Patients After Neoadjuvant Chemotherapy: A Prospective, Randomized, Open-Label, Single-Center Phase 2 Trial

BACKGROUND

This study aimed to compare the sentinel lymph node (SLN) identification rates for breast cancer patients after neoadjuvant chemotherapy (NAC) between the dual method (DM) of indocyanine green fluorescence (ICG-F) plus a radioisotope (RI) and RI alone.

METHODS

This randomized study enrolled 130 patients who received NAC for breast cancer and 122 patients who received SLN biopsy (SLNB) using either DM (n = 58) or RI only (n = 64). The study compared the identification rate, number of SLNs, and detection time of SLNB.

RESULTS

Among the 122 patients, 113 (92.6%) were clinically node-positive before NAC. The SLN identification rate was 98.3% in the DM group and 93.8% in the RI group (p = 0.14). The DM group and the RI group were similar in the average number of SLNs (2.2 ± 1.13 vs. 1.9 ± 1.33; p = 0.26) and the time to detection of the first SLN (8.7 ± 4.98 vs. 8.3 ± 4.31 min; p = 0.30). In the DM group, transcutaneous lymphatic drainage was visualized by fluorescence imaging for 65.5% (38 of 58) of the patients. The SLN identification rate was 94.7% using ICG-F and 93% using RI (p = 0.79). During and after the operation, no complications, including allergic reactions or skin necrosis, occurred.

CONCLUSIONS

This study is the first randomized trial to use ICG-F for SLNB in breast cancer patients after NAC. The DM including ICG-F could be a feasible and safe method for SLNB in initially node-positive breast cancer patients with NAC.

Meta-analysis of sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with initial biopsy-proven node-positive breast cancer

BACKGROUND

Neoadjuvant chemotherapy for breast cancer has the potential to achieve a pathological complete response in up to 40 per cent of patients, converting disease that was initially node-positive to node-negative. This has raised the question of whether sentinel lymph node biopsy could be an alternative to axillary lymph node dissection in these patients. The aim was to undertake a systematic review and meta-analysis of the accuracy and reliability of sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with initial biopsy-proven node-positive breast cancer.

METHODS

A literature search was conducted using PubMed, Ovid MEDLINE, Embase and Web of Science databases up to 30 April 2017. Inclusion criteria for studies were pathological confirmation of initial node-positive disease, and sentinel lymph node biopsy performed after neoadjuvant chemotherapy followed by axillary lymph node dissection.

RESULTS

A total of 13 studies met the inclusion criteria and were included in the analysis (1921 patients in total). The pooled estimate of identification rate was 90 (95 per cent c.i. 87 to 93) per cent and the false-negative rate was 14 (11 to 17) per cent. In subgroup analysis, the false-negative rate with use of dual mapping was 11 (6 to 15) per cent, compared with 19 (11 to 27) per cent with single mapping. The false-negative rate was 20 (13 to 27) per cent when one node was removed, 12 (5 to 19) per cent with two nodes removed and 4 (0 to 9) per cent with removal of three or more nodes.

CONCLUSION

Sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with biopsy-proven node-positive breast cancer is accurate and reliable, but requires careful patient selection and optimal surgical techniques.

Overview of Breast Cancer Therapy

Breast cancer treatment is multidisciplinary. Most women with early stage breast cancer are candidates for breast-conserving surgery with radiotherapy or mastectomy. The risk of local recurrence and the chance of survival does not differ with these approaches. Sentinel node biopsy is used for axillary staging, and individualized approaches are minimizing the need for axillary dissection in women with positive sentinel nodes. Adjuvant systemic therapy is used in most women based on proven survival benefit, and molecular profiling to individualize treatment based on risk is now a clinical reality for patients with hormone receptor-positive cancers.

Possibility of avoiding axillary lymph node dissection by immune microenvironment monitoring in preoperative chemotherapy for breast cancer

Background

The diagnosis of metastasis by sentinel lymph node biopsy (SLNB) in early breast cancer surgery provides an accurate view of the state of metastases to the axillary lymph nodes, and it has now become the standard procedure. In the present study, whether omission of axillary lymph node dissection (ALND) after neoadjuvant chemotherapy (NAC) is possible by evaluation of tumor-infiltrating lymphocytes (TILs) before NAC in cases without metastasis on diagnostic imaging, but with metastasis on SLNB, was retrospectively investigated.

Methods

A total of 91 patients with resectable, early-stage breast cancer, diagnosed as cT1–2, N0, M0, underwent SLNB and were treated with NAC. A semi-quantitative evaluation of lymphocytes infiltrating the peritumoral stroma as TILs in biopsy specimens of primary tumors prior to treatment was conducted.

Results

In cases with a low number of TILs, estrogen receptor expression was significantly higher (p = 0.044), and human epidermal growth factor receptor 2 (HER2) expression was significantly lower than in other cases (p = 0.019). The number of TILs was significantly lower in cases in which the intrinsic subtype was hormone receptor-positive breast cancer (HRBC) (p = 0.044). Metastasis to axillary lymph nodes was significantly more common in HER2-negative cases and cases with a low number of TILs (p = 0.019, p = 0.005, respectively).

Conclusions

Even if macrometastases are found on SLNB in cN0 patients, it appears that ALND could be avoided after NAC in cases with a good immune tumor microenvironment of the primary tumor.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1692-3) contains supplementary material, which is available to authorized users.

Management of the axilla after neo-adjuvant chemotherapy for breast cancer: Sentinel node biopsy and radiotherapy considerations

Preoperative or neo-adjuvant chemotherapy in the management of breast cancer is a treatment approach that has gained in popularity in recent years. However, it is unclear if the treatment paradigms often employed for patients treated with surgery first hold true for those treated with preoperative chemotherapy. The role of sentinel node biopsy and the data supporting its use is different for those with clinically negative and clinically positive nodes prior to chemotherapy. For clinically node-negative patients, sentinel node biopsy after neo-adjuvant chemotherapy may be appropriate. For those node-positive patients whose axillary disease resolves clinically, the false-negative rate of the sentinel node biopsy is high. However, there are measures that can reduce that rate. After surgery, the radiation oncologist is often faced with complicated decisions surrounding the optimal radiotherapy in this setting. Tailoring radiation plans based on chemotherapy response holds promise and is the subject of ongoing clinical trials. In the accompanying article, we review the current literature on both surgery and radiation in axillary management and describe the interplay between these two treatment modalities. This highlights the need for multidisciplinary management in making treatment decisions for patients treated in this manner.

Surgical Standards for Management of the Axilla in Breast Cancer Clinical Trials with Pathological Complete Response Endpoint

Advances in the surgical management of the axilla in patients treated with neoadjuvant chemotherapy, especially those with node positive disease at diagnosis, have led to changes in practice and more judicious use of axillary lymph node dissection that may minimize morbidity from surgery. However, there is still significant confusion about how to optimally manage the axilla, resulting in variation among practices. From the viewpoint of drug development, assessment of response to neoadjuvant chemotherapy remains paramount and appropriate assessment of residual disease—the primary endpoint of many drug therapy trials in the neoadjuvant setting—is critical. Therefore decreasing the variability, especially in a multicenter clinical trial setting, and establishing a minimum standard to ensure consistency in clinical trial data, without mandating axillary lymph node dissection, for all patients is necessary. The key elements which include proper staging and identification of nodal involvement at diagnosis, and appropriately targeted management of the axilla at the time of surgical resection are presented. The following protocols have been adopted as standard procedure by the I-SPY2 trial for management of axilla in patients with node positive disease, and present a framework for prospective clinical trials and practice.

A new model to predict risk of nonsentinel lymph node status in Chinese sentinel lymph node-positive patients after neoadjuvant chemotherapy

There is no previous predictive model to assess risk of nonsentinel lymph node metastases (NSLN) in sentinel lymph node (SLN)-positive breast cancer patients after neoadjuvant chemotherapy (NAT). Our goal was to develop a new predictive model for SLN-positive patients after NAT, and validate this new model. A series of 513 patients with metastases in SLN who received NAT were used to evaluate factors affecting NSLN status. Logistic regression analysis was performed to develop a predictive model, which was validated by a subsequent prospective 138 patients. There were 115 (22.4%) patients with metastases in NSLN followed by axillary lymph node dissection (ALND). Multivariate analysis indicated that tumor (T) stage, number of positive SLN,micrometastases, extracapsular extension (ECE), and clinical response of primary tumor after NAT were significant independent predictors for the NSLN metastases. Area under the curve (AUC) of the model was 0.795 (95% CI, 0.734-0.861). When applied to the prospective series, the model accurately predicted the risk of NSLN disease, AUC was 0.772 (95% CI, 0.653-0.845). We present a new predictive model to assess the risk of NSLN status in Chinese SLN-positive breast cancer patients after NAT. The predictive model performed well in prospective validation but needs to be further studied in external center patients before application to clinical use.

Total pathological complete response versus breast pathological complete response in clinical trials of reference and biosimilar trastuzumab in the neoadjuvant treatment of breast cancer

INTRODUCTION

Trastuzumab is a key drug in the neoadjuvant treatment of breast cancers that overexpress the human epidermal growth factor receptor 2 (HER2). Pathological complete response (pCR) is commonly used as an endpoint in neoadjuvant clinical trials of trastuzumab as evidence suggests it may be a surrogate for long-term survival. Several biosimilar candidates of originator or 'reference' trastuzumab are in development and have used pCR as a primary endpoint to assess therapeutic equivalence between treatments. The exact definition of pCR has varied across studies. Areas covered: Here we look at the clinical relevance of pCR and compare rates of total pCR (defined as ypT0/is ypN0) and breast pCR (defined as ypT0/is) in clinical trials of reference and biosimilar trastuzumab. Expert commentary: In order to evaluate the efficacy of neoadjuvant systemic therapies in a uniform way, standardization of trial endpoints is necessary. Future studies in HER2-positive breast cancer should include full assessment of the breast and lymph node basin before and after neoadjuvant systemic therapy, and the use of total pCR as the primary outcome.

Sentinel Lymph Node Biopsy in Breast Cancer: A Clinical Review and Update

Sentinel lymph node biopsy has become a standard staging tool in the surgical management of breast cancer. The positive impact of sentinel lymph node biopsy on postoperative negative outcomes in breast cancer patients, without compromising the oncological outcomes, is its major advantage. It has evolved over the last few decades and has proven its utility beyond early breast cancer. Its applicability and efficacy in patients with clinically positive axilla who have had a complete clinical response after neoadjuvant chemotherapy is being aggressively evaluated at present. This article discusses how sentinel lymph node biopsy has evolved and is becoming a useful tool in new clinical scenarios of breast cancer management.

Current approach of the axilla in patients with early-stage breast cancer

The surgical approach of the axilla in patients with early-stage breast cancer has witnessed considerable evolution during the past 25 years. The previously undisputed gold standard of axillary-lymph-node dissection for staging has now been replaced by sentinel-lymph-node biopsy for patients with clinically negative axilla. For selected patients with limited sentinel-lymph-node involvement, completion axillary-lymph-node dissection can be omitted or replaced by axillary radiotherapy, reducing morbidity. The clinical interest of axillary staging after neoadjuvant chemotherapy is increasing and this approach might contribute to morbidity reduction, and to the further tailoring of future systemic and locoregional treatment decisions by response assessment. Refinement of the sentinel-lymph-node biopsy technique might overcome the slightly impaired success rates in this setting. New techniques for lymphatic mapping attempt to further simplify the procedure. In view of the declining influence of axillary nodal status on adjuvant therapy decision-making, ongoing clinical trials will evaluate whether sentinel-lymph-node biopsy can be avoided altogether in selected patients.

The Optimal Treatment Plan to Avoid Axillary Lymph Node Dissection in Early-Stage Breast Cancer Patients Differs by Surgical Strategy and Tumor Subtype

BACKGROUND

Strategies to reduce the likelihood of axillary lymph node dissection (ALND) include application of Z0011 or use of neoadjuvant chemotherapy (NAC). Indications for ALND differ by treatment plan, and nodal pathologic complete response rates after NAC vary by tumor subtype. This study compared ALND rates for cT1-2N0 tumors treated with upfront surgery versus those treated with NAC.

METHODS

The ALND rates for cT1-2N0 breast cancer patients were compared by tumor subtype among women undergoing upfront surgery to NAC. Multivariable analysis with control for age, cT stage, and lymphovascular invasion, and stratification by subtype was performed.

RESULTS

The study identified 1944 cancers in 1907 women who underwent sentinel lymph node (SLN) biopsy with or without ALND (669 upfront breast-conserving surgeries [BCSs], 1004 upfront mastectomies, 271 NACs). Compared with the NAC group, the ALND rates in the BCS group were lower for estrogen receptor (ER), progesterone receptor-positive (PR⁺), human epidermal growth factor 2-negative (HER2^-) tumors (15 vs 34%; p < 0.001). The ALND rates in the upfront mastectomy group were higher than in the NAC group for HER2⁺ or TN tumors. In the multivariable analysis, receipt of NAC compared with upfront BCS remained significantly associated with higher odds of ALND in the ER/PR⁺ HER2^- subtype (hazard ratio [HR], 3.35; p < 0.001), whereas NAC versus upfront mastectomy remained significantly associated with lower odds of ALND in the HER2⁺ and TN subtypes (HR for HER2⁺, 0.19, p < 0.001; HR for TN, 0.25, p = 0.007).

CONCLUSION

The study showed that ALND rates differ according to surgery type and tumor subtype secondary to differing ALND indications and nodal response to NAC. These factors can be used to personalize treatment planning to minimize ALND risk for patients with early-stage breast cancer.

Impact of neoadjuvant chemotherapy on surgical outcomes among patients with hormone receptor positive breast cancer

BACKGROUND

Pathologic complete response (pCR) after neoadjuvant chemotherapy (NACT) is a surrogate for outcome, but not necessarily conversion to BCT eligibility. We sought to examine the impact of NACT on surgical decision making among HR+ patients.

METHODS

Our IRB-approved breast cancer database was queried for patients who underwent NACT, including the clinicopathologic data and surgeon's pre- and post-NACT assessment. Surgical conversion rate (SCR) was defined as patients ineligible for BCT prior to NACT, who were given the choice following NACT.

RESULTS

Among 289 patients, pCR rates were highest among patients with HER2-enriched subtype (60%) and lowest in patients with luminal A disease (4%). Overall, the BCT rate was 41%, while 28% opted for bilateral mastectomy across subtypes. Despite a low pCR, the SCR was still high (54%) among patients with the luminal A subtype.

CONCLUSION

Despite poor pCR rates, NACT still has potential to improve surgical outcomes among hormone receptor positive patients. The surgical conversion rate is a superior measure of the impact of NACT on surgical decision making than examining BCT rates.

The intraoperative assessment of sentinel nodes - Standards and controversies

Intraoperative assessment of sentinel lymph nodes (SLNs) has the advantage of allowing breast cancer patients with tumor-positive SLNs to avoid a second surgery by immediately proceeding to axillary lymph node dissection (ALND). However, there are several reasons why the use of intraoperative assessment should be questioned. Whereas ALND was traditionally advised for all breast cancer patients with tumor-positive lymph nodes for axillary staging and locoregional control, more recent studies have demonstrated safety of omitting ALND in a substantial number of patients. In addition, there are concerns about the accuracy of intraoperative assessment methods including frozen section analysis, touch preparation cytology and one-step nucleic acid amplification. Moreover, intraoperative assessment of SLNs denies patients the opportunity to contribute to their treatment planning. In our opinion, intraoperative assessment of axillary lymph nodes should be reserved for patients who still have a strict indication for ALND. Patients with clinical node negative disease (cN0) and one or two positive SLNs can be safely treated with breast conserving surgery and radiotherapy. There has been more controversy for cN0 patients who are treated with mastectomy since radiotherapy is not routinely administered in these patients. However, there is increasing evidence that ALND may be omitted in patients undergoing mastectomy who have a low tumor-burden in their SLNs. Therefore, we defend the position that in cN0 patients undergoing mastectomy, SLNB should be performed and full pathologic evaluation of the SLN should be awaited. In cN0 patients undergoing neoadjuvant systemic therapy (NST) intraoperative assessment of SLNs can be omitted since ALND will not provide therapeutic benefit. It is being hypothesized that patients with limited axillary disease prior to NST who remain node-positive after NST could be treated safely with axillary radiotherapy instead of ALND. In these patients, omitting intraoperative assessment might be a reasonable option. In patients with extensive nodal disease prior to NST intraoperative assessment of axillary lymph nodes should be performed.

New challenges in multimodal workout of locally advanced breast cancer

The term "locally advanced breast cancer" (LABC) encompasses a heterogeneous group of breast neoplasms that represent an extremely variable percentage of newly diagnosed breast cancers (4-90%, depending of world regions). These cancers may have different clinical and biological characteristics that can be managed by primary surgery or neoadjuvant integrated treatments. In this paper we review the updated guidelines and discuss most recently reported evidence related to LABC multidisciplinary workout, in order to maximize results of combined systemic therapies, modern surgical procedures and radiotherapy.

Novel rapid-immunohistochemistry using an alternating current electric field for intraoperative diagnosis of sentinel lymph nodes in breast cancer

Axillary lymph node status and pathological diagnosis of sentinel lymph nodes (SLNs) is a prognostic factor that influences management of postoperative therapy. Recent reports indicate that one-step nucleic acid amplification and hematoxylin and eosin (HE)-stained frozen sections are effective for intraoperative diagnosis of SLNs. In the present study, we report a rapid-immunohistochemical staining (R-IHC) method that enables intraoperative detection of SLN metastases within 16 min using an anti-cytokeratin antibody. This is the first report on SLN diagnosis using R-IHC in patients with breast cancer. We prospectively examined 160 dissected SLNs from 108 breast cancer patients who underwent surgery at our institute. The dissected SLNs were sectioned and conventionally stained with HE or immunohistochemically labeled with anti-cytokeratin antibody using R-IHC procedures. Intraoperative R-IHC analyses were completed within 16 min, after which diagnoses were made by two pathologists. The total time required for intraoperative diagnosis was about 20 min. In this study series, R-IHC detected four metastatic SLNs that were undetected using conventional HE staining (4/20, 20.0%). Compared with subsequent permanent diagnosis, R-IHC offered 95.2% sensitivity and 100% specificity. These findings indicate R-IHC is a clinically applicable technique that enables precise and quick intraoperative detection of micro- and macrometastasis in breast cancer.

Combined PET-CT and axillary lymph node marking with radioactive iodine seeds (MARI procedure) for tailored axillary treatment in node-positive breast cancer after neoadjuvant therapy

BACKGROUND

The treatment of axillary lymph node metastases after neoadjuvant systemic therapy (NST) remains debatable and axillary lymph node dissection (ALND) is still the standard of care. Marking axillary lymph nodes with radioactive iodine seeds (MARI procedure) is accurate in restaging the axilla after NST (false-negative rate 7 per cent). Here, the potential of tailored axillary treatment, determined by combining the results of PET-CT before NST with those of the MARI procedure after NST, was analysed.

METHODS

A cohort of axillary node-positive patients was used to construct a hypothetical treatment algorithm based on a combination of PET-CT and the MARI procedure. In the algorithm, the number of fluorodeoxyglucose (FDG)-avid axillary lymph nodes (1-3 versus 4 or more) before NST and the tumour status of the MARI node (positive versus negative) after NST were used to tailor axillary treatment. All patients in the cohort underwent ALND, allowing estimation of potential overtreatment and undertreatment.

RESULTS

A total of 93 patients were included in the study. Between one and three FDG-avid axillary lymph nodes were observed in 59 patients, and four or more in 34 patients. The MARI node was tumour-negative in 32 patients and showed residual disease in 61. Treatment according to the constructed algorithm would have resulted in 74 per cent of patients avoiding an ALND, with potential undertreatment in three patients (3 per cent) and overtreatment in 16 (17 per cent).

CONCLUSION

Tailored axillary treatment after NST in node-positive patients, by combining PET-CT before NST and the MARI procedure after NST, has the potential for ALND to be avoided in 74 per cent of patients.