Measuring the impact of the American College of Surgeons Oncology Group Z0011 trial on breast cancer surgery in a community health system

Update on Sentinel Lymph Node Methods and Pathology in Breast Cancer

Breast cancer stands out as the most commonly diagnosed cancer among women globally. Precise lymph node staging holds critical significance for both predicting outcomes in early-stage disease and formulating effective treatment strategies to control regional disease progression in breast cancer patients. No imaging technique possesses sufficient accuracy to identify lymph node metastases in the early stages (I or II) of primary breast cancer. However, the sentinel node procedure emerges as a valuable approach for identifying metastatic axillary nodes. The sentinel lymph node is the hypothetical first lymph node or group of nodes draining a cancer. In case of established cancerous dissemination, it is postulated that the sentinel lymph nodes are the target organs primarily reached by metastasizing cancer cells from the tumor. The utilization of the sentinel node technique has brought about changes in the assessment of lymph nodes. It involves evaluating the sentinel node during surgery, enabling prompt lymph node dissection when the sentinel node procedure is positive. Additionally, histological ultra-stratification is employed to uncover occult metastases. This review aims to provide an update of this valuable technique, with focus on the practical aspects of the procedure and the different histological protocols of sentinel node evaluation in breast cancer.

Update on sentinel node pathology in breast cancer

Pathologic examination of the sentinel lymph nodes (SLNs) in patients with breast cancer has been impacted by the publication of practicing changing trials over the last decade. With evidence from the ACOSOG Z0011 trial to suggest that there is no significant benefit to axillary lymph node dissection (ALND) in early-stage breast cancer patients with up to 2 positive SLNs, the rate of ALND, and in turn, intraoperative evaluation of SLNs has significantly decreased. It is of limited clinical significance to pursue multiple levels and cytokeratin immunohistochemistry to detect occult small metastases, such as isolated tumor cells and micrometastases, in this setting. Patients treated with neoadjuvant therapy, who represent a population with more extensive disease and aggressive tumor biology, were not included in Z0011 and similar trials, and thus, the evidence cannot be extrapolated to them. Recent trials have supported the safety and accuracy of sentinel lymph node biopsy (SLNB) in these patients when clinically node negative at the time of surgery. ALND remains the standard of care for any amount of residual disease in the SLNs and intraoperative evaluation of SLNs is still of value for real time surgical decision making. Given the potential prognostic significance of residual small metastases in treated lymph nodes, as well as the decreased false negative rate with the use of cytokeratin immunohistochemistry (IHC), it may be reasonable to maintain a low threshold for the use of cytokeratin IHC in post-neoadjuvant cases. Further recommendations for patients treated with neoadjuvant therapy await outcomes data from ongoing clinical trials. This review will provide an evidence-based discussion of best practices in SLN evaluation.

Analysis of a Trend Reversal in US Lumpectomy Rates From 2005 Through 2017 Using 3 Nationwide Data Sets

Importance

Rates of lumpectomy for breast cancer management in the United States previously declined in favor of more aggressive surgical options, such as mastectomy and contralateral prophylactic mastectomy (CPM).

Objective

To evaluate longitudinal trends in the rates of lumpectomy and mastectomy, including unilateral mastectomy vs CPM rates, and to determine characteristics associated with current surgical practice using 3 national data sets.

Design and Setting

Data from the National Surgical Quality Improvement Program (NSQIP), Surveillance, Epidemiology, and End Results (SEER) program, and National Cancer Database (NCDB) were examined to evaluate trends in lumpectomy and mastectomy rates from 2005 through 2017. Mastectomy rates were also evaluated with a focus on CPM. Longitudinal trends were analyzed using the Cochran-Armitage test for trend. Multivariate logistic regression models were performed on the NCDB data set to identify predictors of lumpectomy and CPM.

Results

A study sample of 3 467 645 female surgical breast cancer patients was analyzed. Lumpectomy rates reached a nadir between 2010 and 2013, with a significant increase thereafter. Conversely, in comparison with lumpectomy rates, overall mastectomy rates declined significantly starting in 2013. Cochran-Armitage trend tests demonstrated an annual decrease in lumpectomy rates of 1.31% (95% CI, 1.30%-1.32%), 0.07% (95% CI, 0.01%-0.12%), and 0.15% (95% CI, 0.15%-0.16%) for NSQIP, SEER, and NCDB, respectively, from 2005 to 2013 (P < .001, P = .01, and P < .001, respectively). From 2013 to 2017, the annual increase in lumpectomy rates was 0.96% (95% CI, 0.95%-0.98%), 1.60% (95% CI, 1.59%-1.62%), and 1.66% (95% CI, 1.65%-1.67%) for NSQIP, SEER, and NCDB, respectively (all P < .001). Comparisons of specific mastectomy types showed that unilateral mastectomy and CPM rates stabilized after 2013, with unilateral mastectomy rates remaining higher than CPM rates throughout the entire time period.

Conclusions

This observational longitudinal analysis indicated a trend reversal with an increase in lumpectomy rates since 2013 and an associated decline in mastectomies. The steady increase in CPM rates from 2005 to 2013 has since stabilized. The reasons for the recent reversal in trends are likely multifactorial. Further qualitative and quantitative research is required to understand the factors driving these recent practice changes and their associations with patient-reported outcomes.

Axillary Lymph Node Dissection Can Be Omitted in Breast Cancer Patients With Mastectomy and False-Negative Frozen Section in Sentinel Lymph Node Biopsy

Background

The IBCSG 23-01 and AMAROS trials both reported that axillary lymph node dissection (ALND) did not change survival rates in breast cancer patients with positive nodes detected by sentinel lymph node biopsy (SLNB). The aim of this study was to determine whether breast cancer patients with mastectomy and false-negative frozen section (FS) in SLNB could forgo ALND.

Materials and Methods

This was a retrospective study of cN0 patients diagnosed with primary invasive breast cancer treated by mastectomy and SLNB at our institute between January 2010 and December 2014. Patients with false-negative FS in SLNB were separated by the following management of axillary lymph node dissection in the non-ALND group (nonprocess or axillary radiation only) and ALND group (with or without radiation).

Results

A total of 212 patients were included, 86 and 126 patients in the non-ALND and ALND groups, respectively. The positive rate of non-sentinel lymph nodes (SLNs) was 15.87% (20/126) in the ALND group. In multivariate analysis, we found that patients with larger tumor size (>2 cm) (OR, 1.989; p = 0.030) and multifocal lesions (OR, 3.542; p = 0.029) tended to receive ALND. The positivity of non-SLNs in the ALND group was associated with SLN macrometastasis (OR, 3.551; p = 0.043) and lymphovascular invasion (OR, 6.158; p = 0.003). Also, removing more SLNs (≥3) was related to negativity in non-SLNs (OR, 0.255; p = 0.016). After a median follow-up of 59.43 months, RFS and OS of the two groups were similar (p = 0.994 and 0.441). In subgroup analysis, we found that 97 patients who met the inclusive criteria of the IBCSG 23-01 trial had similar RFS and OS between the non-ALND and ALND groups (p = 0.856 and 0.298). The positive rate of non-SLNs was 9.62% (5/52). Also, in 174 patients who met the criteria of the AMAROS trial, RFS and OS in the non-ALND and ALND groups were similar (p = 0.930 and 0.616). The positive rate of non-SLNs was 18.27% (19/104).

Conclusion

ALND can be carefully omitted in selected breast cancer patients with mastectomy and false-negative FS in SLNB. SLNB is relatively sufficient in the IBCSG 23-01-eligible patients, and axillary radiation was an effective option in the AMAROS-eligible patients.

Variation in Deescalated Axillary Surgical Practices in Older Women with Early-Stage Breast Cancer

BACKGROUND

Randomized controlled trials show that certain axillary surgical practices can be safely deescalated in older adults with early-stage breast cancer. Hospital volume is often equated with surgical quality, but it is unclear whether this includes performance of low-value surgeries. We sought to describe how utilization of two low-value axillary surgeries has varied by time and hospital volume.

METHODS

Women aged ≥ 70 years diagnosed with breast cancer from 2013 to 2016 were identified in the National Cancer Database. The outcomes of interest were sentinel lymph node biopsy (SLNB) in cT1N0 hormone receptor-positive cancer patients and axillary lymph node dissection (ALND) in cT1-2N0 patients undergoing breast-conserving surgery with ≤ 2 pathologically positive nodes. Time trends in procedure use and multivariable regression with restricted cubic splines were performed, adjusting for patient, disease, and hospital factors.

RESULTS

Overall, 83.4% of 44,779 women eligible for omission of SLNB underwent SLNB and 20.0% of 7216 patients eligible for omission of ALND underwent ALND. SLNB rates did not change significantly over time and remained significantly different by age group (70-74 years: 93.5%; 75-79 years: 89.7%, 80-84 years: 76.7%, ≥ 85 years: 48.9%; p < 0.05). ALND rates decreased over the study period across all age groups included (22.5 to 16.9%, p < 0.001). In restricted cubic splines models, lower hospital volume was associated with higher likelihood of undergoing SLNB and ALND.

CONCLUSIONS

ALND omission has been more widely adopted than SLNB omission in older adults, but lower hospital volume is associated with higher likelihood of both procedures. Practice-specific deimplementation strategies are needed, especially for lower-volume hospitals.

Choice of Mastectomy May Increase the Extent of Axillary Surgery in Women with Breast Cancer

INTRODUCTION

Based on the ACOSOG Z0011 trial, women who undergo breast conservation therapy (BCT) and have limited disease in the axilla on sentinel lymph node (SLN) biopsy do not require axillary lymph node dissection (ALND). In this study we investigate the incidence of ALND in patients undergoing elective mastectomy with limited disease in the axilla to identify how many women may have been spared additional axillary surgery if they chose BCT.

METHODS

All women with invasive breast cancer treated at a single tertiary care breast center from 2010-2018 who were candidates for BCT but elected mastectomy and underwent SLN biopsy were identified through retrospective review of a prospectively maintained database. The primary outcome of interest was the incidence of ALND in women found to have a limited burden of disease in the axilla (1-2 positive SLNs).

RESULTS

The study population comprised 151 patients with invasive breast cancer eligible for BCT who chose mastectomy. On final pathology, 34 patients had 1-2 positive SLNs, and 16 of these patients underwent completion ALND. These 16 patients out of 151 overall lumpectomy candidates electing mastectomy (10.6%) could have been spared ALND if they did not elect mastectomy.

DISCUSSION

BCT candidates electing mastectomy have a 10.6% chance of undergoing more extensive axillary surgery than would have been recommended with BCT alone. The increased risk of undergoing additional axillary surgery should be incorporated into the preoperative discussion for patients choosing between BCT and mastectomy.

High Compliance With Choosing Wisely Breast Surgical Guidelines at a Safety-Net Hospital

BACKGROUND

Professional organizations recently set guidelines for avoiding surgeries of low utility and overutilization for the Choosing Wisely campaign. These include re-excision for invasive cancer close to margins, double mastectomy in patients with unilateral breast cancer, axillary lymph node dissection in patients with limited nodal disease, and sentinel lymph node biopsy (SLNB) in patients ≥70 years with early-stage breast cancer. Variable adherence to these recommendations led us to evaluate implementation rates of low-value surgical guidelines at a safety-net hospital.

METHODS

We retrospectively analyzed breast cancer patients who underwent surgery from 2015 to 2020. Each patient was assessed for eligibility for omission of the listed surgeries. Trends were evaluated by cohorts before and after a fellowship-trained breast surgeon joined the faculty in 2018. Outcomes were compared using Fisher's exact test.

RESULTS

Among 195 patients, none underwent re-excision for close margins of invasive cancer. Only 6.7% of patients (3/45) received contralateral mastectomy and 1.8% of eligible patients (3/169) received axillary lymph node dissection. Overall, 60% of patients ≥ 70 years with stage 1 hormone-positive breast cancer (9/15) received SLNB. There was a downward trend from 71% of eligible patients receiving SLNB in 2015-2018 to 50% in 2019-2020.

CONCLUSIONS

De-implementation of traditional surgical practices, deemed as low-value care, toward newer guidelines is achievable even at community hospitals serving a low socioeconomic community. By avoiding overtreatment, hospitals can achieve effective resource allocation which allow for social distributive justice among patients with breast cancer and ensure strategic use of scarce health economic resources while preserving patient outcomes.

Predictive factors of lymph node metastasis and effectiveness of intraoperative examination of sentinel lymph node in breast carcinoma: A retrospective Belgian study

Recently, several trials demonstrated the safety of omitting axillary lymph node dissection in clinically N0 patients with positive sentinel nodes in select subgroups. However, this fact is still troublesome to clarify to surgeons and clinicians, as they used to perform intraoperative examination of the sentinel node and axillary dissection for many years. Hence, we decided to review our practice. This is to firstly highlight the predictive factors of node metastasis and secondly, to evaluate the effectiveness of intraoperative examination of the sentinel node. There were 406 total procedures. The rate of positive lymph nodes in the final diagnosis was 27%. Factors associated with metastasis were age, tumour size, TNM classification, tumour grade, vascular invasion, molecular classification and KI-67 index. The rate of reoperation was 6.2% in cases with final positive nodes, however, the complementary ALND was justified in only 2.7%. Forty-nine percent of SLN were examined during surgery (IOESLN), whereby the false negative rate was 11.8%. Sixty-three intraoperative examinations were necessary to prevent a second operation on a patient. We recommend changing the clinical management of the axilla, resulting in fewer ALNDs in selected cN0, SLN-positive patients. In keeping with recent large clinical trial (ACOSOG Z0011, AMAROS and OTOASOR) data, our results support that intraoperative exam in selected cN0, SLN-positive Belgian patients is no longer effective.

Deimplementation of the Choosing Wisely Recommendations for Low-Value Breast Cancer Surgery

Importance

Overtreatment of early-stage breast cancer results in increased morbidity and cost without improving survival. Major surgical organizations participating in the Choosing Wisely campaign identified 4 breast cancer operations as low value: (1) axillary lymph node dissection for limited nodal disease in patients receiving lumpectomy and radiation, (2) re-excision for close but negative lumpectomy margins for invasive cancer, (3) contralateral prophylactic mastectomy in patients at average risk with unilateral cancer, and (4) sentinel lymph node biopsy in women 70 years or older with hormone receptor-positive cancer.

Objective

To evaluate the extent to which these procedures have been deimplemented, determine the implications of decreased use, and recognize possible barriers and facilitators to deimplementation.

Evidence Review

A systematic review of published literature on use trends in breast surgery was performed in accordance with PRISMA guidelines. The Ovid, Embase, Cumulative Index to Nursing and Allied Health Literature, and Cochrane databases were searched for original research with relevance to the Choosing Wisely recommendations of interest. Eligible studies were examined for data about use, and any patient-level, clinician-level, or system-level factors associated with use.

Findings

Concordant with recommendations, national rates of axillary lymph node dissection for patients with limited nodal disease have decreased by approximately 50% (from 44% in 2011 to 30% to 34% in 2012 and 25% to 28% in 2013), and national rates of lumpectomy margin re-excision have decreased by nearly 40% (from 16% to 34% before to 14% to 18% after publication of a consensus statement). Conversely, national rates of contralateral prophylactic mastectomy continue to rise each year, accounting for up to 30% of all mastectomies for breast cancer (range in all mastectomy cases: 2010-2012, 28%-30%; 1998, <2%), and rates of sentinel lymph node biopsy in women 70 years or older with low-risk breast cancer are persistently greater than 80% (range, 80%-88%). Factors associated with high rates of contralateral prophylactic mastectomy use are younger age, white race, increased socioeconomic status, and the availability of breast reconstruction; limited data exist on factors associated with high rates of sentinel lymph node biopsy in women 70 years or older. Successful deimplementation of axillary lymph node dissection and lumpectomy margin re-excision were associated with decreased costs and improved patient-centered outcomes.

Conclusions and Relevance

This review demonstrates variable deimplementation of 4 low-value surgical procedures in patients with breast cancer. Addressing specific patient-level, clinician-level, and system-level barriers to deimplementation is necessary to encourage shared decision-making and reduce overtreatment.

Sentinel node theory helps tracking of primary lesions of cancers of unknown primary

Background

Sentinel lymph node is the first stop of lymphatic spreading of cancer with known primary. The lymph node metastasis pattern of cancer of unknown primary (CUP) is unclear and has been presumed to follow the same pathway. To test this hypothesis, data of all 716 patients clinically diagnosed as CUP in our center were collected.

Methods

Diagnoses of lymph node metastasis were established by ¹⁸F-FDG PET-CT and/or biopsy pathology. Three hundred and forty-seven cases meeting the criteria were divided into three groups: pathology-confirmed primary with invasive biopsy or surgery of the suspicious lesion (group A, n = 64), primary still unknown even with invasive biopsy or surgery of the suspicious lesion (group B, n = 204), and others with no suspicious lesion or lesions who had not been sampled due to medical or other reasons (group C, n = 79). We assessed the clinicopathological features between these groups, and the relationship between lymph node metastasis pattern and confirmed primary site.

Results

In group A, the primary sites of 61 cases were compatible with sentinel node theory, resulting in a positive predictive value of 95%. No significant differences in age, sex, bone metastasis, or visceral metastasis observed between group A and group B, except that group A had a higher ratio of differentiated carcinoma (94% vs. 77%, P = 0.003).

Conclusion

To our knowledge, this is the first evidence indicating that the majority of clinical CUP cases follow the sentinel node theory to spread in lymph nodes, which helps tracking the primary, especially for differentiated carcinoma.

Assessment of Technical Skills in Axillary Lymph Node Dissection

OBJECTIVE

A simulator to enable safe practice and assessment of ALND has been designed, and face, content and construct validity has been investigated.

SUMMARY AND BACKGROUND DATA

The reduction in the number of ALNDs conducted has led to decreased resident exposure and confidence.

METHODS

A cross-sectional multicenter observational study was carried out between July 2017 and August 2018. Following model development, 30 surgeons of varying experience (n = "experts,' n = 11 "senior residents,' and n = 10 "junior residents") were asked to perform a simulated ALND. Face and content validity questionnaires were administered immediately after ALND. All ALND procedures were retrospectively assessed by 2 attending breast surgeons, blinded to operator identity, using a video-based assessment tool, and an end product assessment tool.

RESULTS

Statistically significant differences between groups were observed across all operative subphases on the axillary clearance assessment tool (P < 0.001). Significant differences between groups were observed for overall procedure quality (P < 0.05) and total number of lymph nodes harvested (P < 0.001). However, operator grade could not be distinguished across other end product variables such as axillary vein damage (P = 0.864) and long thoracic nerve injury (P = 0.094). Overall, participants indicated that the simulator has good anatomical (median score >7) and procedural realism (median score >7).

CONCLUSIONS

Video-based analysis demonstrates construct validity for ALND assessment. Given reduced ALND exposure, this simulation is a useful adjunct for both technical skills training and formative Deanery or Faculty administered assessments.

The value and practical utility of intraoperative touch imprint cytology of sentinel lymph node(s) in patients with breast cancer: A retrospective cytology-histology correlation study

Objective:

Intraoperative evaluation of sentinel lymph nodes (SLNs) for patients with breast cancer is widely performed with frozen section (FS), cytology, or a combination of both. Touch imprint cytology (TIC) reportedly has an equivalent sensitivity to FS. We studied its diagnostic utility to detect SLN metastases.

Materials and Methods:

Cases of 367 patients with breast cancer who underwent intraoperative valuation of SLNs (507 LNs) were evaluated. All FS and corresponding TIC slides of SLNs of each case were reviewed microscopically for the presence of metastases of any size. If present, the metastatic focus was measured on the FS.

Results:

Of these 507 SLNs, 82 LNs (16.2%) from 69 women were found to have metastases in the FS and consisted of 5 LNs of isolated tumor cells, 15 of micrometastasis, and 62 of macrometastasis. TIC identified metastases in 69 of these 82 SLNs (sensitivity: 84.1%, specificity: 100%, and accuracy: 97.4%). All macrometastases could be detected by TIC, whereas TIC identified approximately 50% of micrometastases and none of isolated tumor cells. The size detection limit of metastatic foci, defined as the smallest dimension of metastasis detected without false negatives, was 2 mm. The smallest metastatic focus identified was 0.8 mm.

Conclusions:

TIC of SLNs is of great use given its negative predictive value of 100% for identification of macrometastasis in our study. For intraoperative evaluation of SLNs, based on our data, a practical two-step approach is proposed: SLN evaluation should be initially performed by TIC and then proceed to FS histological analysis only when cytologically positive to determine the size of metastatic focus.

Clinical relevance of total choline (tCho) quantification in suspicious lesions on multiparametric breast MRI

Purpose

To assess the additional value of quantitative tCho evaluation to diagnose malignancy and lymph node metastases in suspicious lesions on multiparametric breast MRI (mpMRI, BI-RADS 4, and BI-RADS 5).

Methods

One hundred twenty-one patients that demonstrated suspicious multiparametric breast MRI lesions using DCE, T2w, and diffusion-weighted (DW) images were prospectively enrolled in this IRB-approved study. All underwent single-voxel proton MR spectroscopy (¹H-MRS, point-resolved spectroscopy sequence, TR 2000 ms, TE 272 ms) with and without water suppression. The total choline (tCho) amplitude was measured and normalized to millimoles/liter according to established methodology by two independent readers (R1, R2). ROC-analysis was employed to predict malignancy and lymph node status by tCho results.

Results

One hundred three patients with 74 malignant and 29 benign lesions had full ¹H-MRS data. The area under the ROC curve (AUC) for prediction of malignancy was 0.816 (R1) and 0.809 (R2). A cutoff of 0.8 mmol/l tCho could diagnose malignancy with a sensitivity of > 95%. For prediction of lymph node metastases, tCho measurements achieved an AUC of 0.760 (R1) and 0.788 (R2). At tCho levels < 2.4 mmol/l, no metastatic lymph nodes were found.

Conclusion

Quantitative tCho evaluation from ¹H-MRS allowed diagnose malignancy and lymph node status in breast lesions suspicious on multiparametric breast MRI. tCho therefore demonstrated the potential to downgrade suspicious mpMRI lesions and stratify the risk of lymph node metastases for improved patient management.

Key Points

• Quantitative tCho evaluation can distinguish benign from malignant breast lesions suspicious after multiparametric MRI assessment.

• Quantitative tCho levels are associated with lymph node status in breast cancer.

• Quantitative tCho levels are higher in hormonal receptor positive compared to hormonal receptor negative lesions.

Electronic supplementary material

The online version of this article (10.1007/s00330-020-06678-z) contains supplementary material, which is available to authorized users.

[Strategies in case of metastatic sentinel lymph node in breast cancer]

Management strategy of micro or macro metastatic sentinel lymph node(s) (SLNs) in breast cancer has dramatically changed over the past ten years and the publication of five randomized trials results: ACOSOG Z0011, IBCSG 23-01, and AATRM comparing axillary lymph node dissection (ALND) versus SLNs biopsy alone; and AMAROS and OTOASOR comparing ALND versus axillary radiotherapy. Despite methodological limitations of several of these trials, notably ACOSOG Z0011, the international recommendations (ASCO, NCCN) and the expert consensus of St Gallen do not recommend the performance of a complementary ALND in case of macro or micro metastatic SLN, if all ACOSOG Z0011 inclusion criteria are met. Moreover, in the context of a mastectomy, with one or two positive SLN and a wall irradiation indication, an axillary radiotherapy can be proposed as an alternative to ALND. Additionally, ALND is also indicated in extracapsular involvement or when three or more SLNs are metastatic. This change in strategy led to a significant decrease on the number of ALNDs performed and resulted on the abandon of SLNs extemporaneous examination. In France, there are no national recommendations on axillary management in the context of SLN involvement. Moreover, a multitude of different local guidelines, led to very heterogeneous practices in our country. The next evolution on axillary management strategy will be the implementation of a SLNs procedure after neoadjuvant chemotherapy (NAC) for patients with lymph node involvement proven before NAC and for whom NAC has allowed axillary downstaging.

Axillary dissection in sentinel lymph node positive breast cancer: Is the staging information worthwhile for patients?

AIMS

The Z0011 randomized trial demonstrated no significant difference in axillary recurrence rate or survival with or without axillary dissection in patients with a positive sentinel node biopsy. However, there is continuing controversy regarding the generalizability of its results, and axillary dissection provides additional pathologic staging information that may guide adjuvant therapy. Thus, axillary dissection after positive sentinel node biopsy is being further investigated in an actively recruiting randomized trial. We elicited patients' preferences for axillary dissection versus no axillary dissection after positive sentinel node biopsy for early breast cancer.

METHODS

Patients who had undergone axillary dissection after positive sentinel node biopsy as part of breast conserving therapy were provided with a validated, self-rated questionnaire. The questionnaire comprised two trade-off questions to determine the maximum chance of developing arm side-effects from axillary dissection to justify the benefit of additional axillary staging information. Social, demographic, and clinical details were collected.

RESULTS

Ninety-nine of the 126 eligible patients returned the questionnaire and 76 completed the trade-off assessment. The median age of participants was 62 years. The median numbers of sentinel and axillary nodes removed were 2 and 12, respectively. Forty-seven percent of participants had arm swelling or tenderness of any severity. Seventy-five percent of participants would have axillary dissection even if the chance of arm side-effects like they had experienced was 100%.

CONCLUSION

Most patients with early breast cancer preferred axillary dissection after positive sentinel node biopsy for the additional staging information even though there was no survival benefit from axillary dissection.

NSQIP Analysis of Axillary Lymph Node Dissection Rates for Breast Cancer: Implications for Resident and Fellow Participation

INTRODUCTION

Management of the axilla in invasive breast cancer (IBC) has shifted away from more radical surgery such as axillary lymph node dissection (ALND), towards less invasive procedures, such as sentinel lymph node biopsy. Because of this shift, we hypothesize that there has been a national downward trend in ALND procedures, subsequently impacting surgical trainee exposure to this procedure using the ACS-NSQIP database to evaluate this.

METHODS

Women with IBC were identified in the ACS-NSQIP database from 2007 to 2014. Procedures including ALND were identified using CPT codes. This number was divided by total cases, given a varying number of participating institutions each year. Next, cases involving resident participation were identified and divided by training level: junior (post graduate year-[PGY] 1-2), senior (PGY 3-5) and fellow (PGY ≥ 6). Two tailed z tests were used to compare proportions, with significance determined when p < 0.05.

RESULTS

A total of 128,372 women were identified with IBC with 36,844 ALND. ALND rates decreased by an average of 2.43% yearly from 2007 to 2014. Resident participation significantly drops in 2011, from 49.3% before to 29.4% after (p < 0.01). Junior residents experienced a significant decrease in participation rate (43.3%-32.2%, p < 0.05). Senior residents and fellows experienced an upward trend in their participation, although not significant (51.2%-56.3%, p = 0.35, and 5.6%-11.6%, p = 0.056, respectively).

CONCLUSIONS

Using the ACS-NSQIP database, we demonstrate the downward trend in rate of ALND for IBC with subsequent decrease in resident participation. Junior residents experienced a significant decrease in their participation with no significant change for senior or fellow-level trainees. Awareness of this trend is important when creating future surgical curriculum changes for general surgery and fellowship training programs.

The impact of axillary ultrasound with biopsy in overtreatment of early breast cancer

PURPOSE

(a) To compare the axillary tumor burden detected by fine-needle aspiration cytology (FNAC) versus sentinel lymph node biopsy (SLNB). (b) To evaluate the relationship between axillary tumor burden and the number of suspicious lymph nodes detected by axillary ultrasonography (US). (c) To calculate the false-positive and false-negative rates for FNAC in patients fulfilling ACOSOG Z0011 criteria.

METHODS

Retrospective multicenter cross-sectional study of 355 pT1 breast cancers. SLNB and axillary lymph node dissection (ALND) were gold standards. Low axillary burden (≤2 positive lymph nodes); high burden (>2 positive lymph nodes). Patients ACOSOG Z0011: false-positive (positive FNAC+low burden), false-negative (negative FNAC+high burden).

RESULTS

High axillary burden: in entire series 38.5% FNAC+ vs. 5.7% SLNB+ (p<0.0001). In subgroup fulfilling ACOSOG Z0011 criteria: 45.5% vs 6.7%, respectively (p<0.001). 61 positive axillary US. With 1 suspicious node on axillary US: 95.6% had ≤2 involved nodes (including pN0); with 2 suspicious nodes: 60% had >2 involved nodes. In ACOSOG Z0011 patients, with 1 suspicious node, 93.7% had ≤2 involved nodes. Of the 37 FNAC in ACOSOG Z0011patients: 54.5% false-positives for high burden; 3.8% false-negatives.

CONCLUSIONS

FNAC-positive tumors have greater axillary burden, even in patients fulfilling ACOSOG Z0011 criteria. Using axillary US/FNAC to triage patients meeting Z0011 criteria may result in axillary overtreatment. The number of suspicious nodes seen in axillary US is related with the final axillary burden and should be taken into account when deciding to do FNAC in patients fulfilling ACOSOG Z0011 criteria.

Application of ACOSOG Z1071: Effect of Results on Patient Care and Surgical Decision-Making

BACKGROUND

The ACOSOG (American College of Surgeons Oncology Group) Z1071 assessed the feasibility of performing sentinel lymph node biopsy (SLNB) in node-positive patients who completed neoadjuvant chemotherapy (NACT). Historically, adoption of clinical research into practice takes years. The goal of this study was to determine the effect of Z1071 on our practice.

MATERIALS AND METHODS

This is a retrospective review of Z1071's influence on a single institution's practice. Patients with biopsy-proven positive axillary lymph nodes before NACT were eligible for the study. After NACT, patients with nodal response according to imaging and exam were candidates for SLNB. Two cohorts were stratified according to diagnosis date before and after Z1071 results were presented on December 5, 2012 at the San Antonio Breast Cancer Symposium. Fisher exact tests and nonparametric rank tests were used to compare cohorts.

RESULTS

The pre-Z1071 cohort included 74 patients and the post-Z1071 cohort 56 for a total of 130 patients. Post-Z1071, 73% (41/56) underwent a SLNB with an average of 4 nodes removed. Moreover, 27% (15/56) of patients had an axillary lymph node dissection as first intervention post-Z1071, compared with 99% (73/74) pre-Z1071. Axillary pathologic complete response pre-Z1071 was 35% (26/74) and post-Z1071 was 27% (15/56) (P = .35).

CONCLUSION

This report shows that meaningful practice changes can be implemented rapidly. Changes in practice generated by clinical trial results should be monitored and outcomes followed.

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.

Development of nomograms to predict axillary lymph node status in breast cancer patients

BACKGROUND

Prediction of axillary lymph node (ALN) status preoperatively is critical in the management of breast cancer patients. This study aims to develop a new set of nomograms to accurately predict ALN status.

METHODS

We searched the National Cancer Database to identify eligible female breast cancer patients with profiles containing critical information. Patients diagnosed in 2010-2011 and 2012-2013 were designated the training (n = 99,618) and validation (n = 101,834) cohorts, respectively. We used binary logistic regression to investigate risk factors for ALN status and to develop a new set of nomograms to determine the probability of having any positive ALNs and N2-3 disease. We used ROC analysis and calibration plots to assess the discriminative ability and accuracy of the nomograms, respectively.

RESULTS

In the training cohort, we identified age, quadrant of the tumor, tumor size, histology, ER, PR, HER2, tumor grade and lymphovascular invasion as significant predictors of ALNs status. Nomogram-A was developed to predict the probability of having any positive ALNs (P_any) in the full population with a C-index of 0.788 and 0.786 in the training and validation cohorts, respectively. In patients with positive ALNs, Nomogram-B was developed to predict the conditional probability of having N2-3 disease (P_con) with a C-index of 0.680 and 0.677 in the training and validation cohorts, respectively. The absolute probability of having N2-3 disease can be estimated by P_any*P_con. Both of the nomograms were well-calibrated.

CONCLUSIONS

We developed a set of nomograms to predict the ALN status in breast cancer patients.

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.

Sentinel Lymph Nodes for Breast Carcinoma: A Paradigm Shift

CONTEXT

-Sentinel lymph node biopsy has been established as the new standard of care for axillary staging in most patients with invasive breast carcinoma. Historically, all patients with a positive sentinel lymph node biopsy result underwent axillary lymph node dissection. Recent trials show that axillary lymph node dissection can be safely omitted in women with clinically node negative, T1 or T2 invasive breast cancer treated with breast-conserving surgery and whole-breast radiotherapy. This change in practice also has implications on the pathologic examination and reporting of sentinel lymph nodes.

OBJECTIVE

-To review recent clinical and pathologic studies of sentinel lymph nodes and explore how these findings influence the pathologic evaluation of sentinel lymph nodes.

DATA SOURCES

-Sources were published articles from peer-reviewed journals in PubMed (US National Library of Medicine) and published guidelines from the American Joint Committee on Cancer, the Union for International Cancer Control, the American Society of Clinical Oncology, and the National Comprehensive Cancer Network.

CONCLUSIONS

-The main goal of sentinel lymph node examination should be to detect all macrometastases (>2 mm). Grossly sectioning sentinel lymph nodes at 2-mm intervals and evaluation of one hematoxylin-eosin-stained section from each block is the preferred method of pathologic evaluation. Axillary lymph node dissection can be safely omitted in clinically node-negative patients with negative sentinel lymph nodes, as well as in a selected group of patients with limited sentinel lymph node involvement. The pathologic features of the primary carcinoma and its sentinel lymph node metastases contribute to estimate the extent of non-sentinel lymph node involvement. This information is important to decide on further axillary treatment.

A Population-Based Study of the Effects of a Regional Guideline for Completion Axillary Lymph Node Dissection on Axillary Surgery in Patients with Breast Cancer

INTRODUCTION

Evidence from the American College of Surgeons Oncology Group (ACOSOG) Z0011 trial suggests completion axillary lymph node dissection (cALND) after positive sentinel lymph node biopsy (+SLNB) does not improve outcomes in select patients, leading to practice variation. A multidisciplinary group of surgeons, oncologists, and pathologists developed a regional guideline for cALND which was disseminated in August 2012. We assessed the impact of Z0011 and the regional guideline on cALND rates.

METHODS

Consecutive invasive breast cancer cases undergoing SLNB were reviewed at 12 hospitals. Patient, tumor, and process measures were collected for three time periods: TP1, before publication of Z0011 (May 2009-August 2010); TP2, after publication of Z0011 (March 2011-June 2012); and TP3, after guideline dissemination (January 2013-April 2014). Cases were categorized by whether they met the guideline criteria for cALND (i.e. ≤50 years, mastectomy, T3 tumor, three or more positive sentinel lymph nodes [SLNs]) or not (e.g. age > 50 years, breast-conserving surgery, T1/T2 tumor, and one to two positive SLNs).

RESULTS

The SLNB rate increased from 56 % (n = 620), to 70 % (n = 774), to 78 % (n = 844) in TP1, TP2, and TP3, respectively. Among cases not recommended for cALND using the guideline criteria, cALND rates decreased significantly over time (TP1, 71 %; TP2, 43 %; TP3, 17 %) [p < 0.001]. The cALND rate also decreased over time among cases recommended to have cALND using the guideline criteria (TP1, 92 %; TP2, 69 %; TP3, 58 %) [p < 0.001]. Based on multivariable analysis, age and nodal factors appeared to be significant factors for cALND decision making.

CONCLUSION

Publication of ACOSOG Z0011 and regional guideline dissemination were associated with a marked decrease in cALND after +SLNB, even among several cases in which the guideline recommended cALND.

Impact of American College of Surgeons Oncology Group Z11 on surgical training at an academic cancer center

BACKGROUND

The application of the American College of Surgeons Oncology Group Z0011 trial (Z11) has resulted in fewer completion axillary lymph node dissections (ALNDs) for select patients. We hypothesize that the application of Z11 may result in fewer ALND cases for surgeons in training.

METHODS

In the setting of an academic cancer center incorporating Z11 into routine practice, we compared the total number of ALND performed in a pre-Z11 period (January 2007-April 2011, 52 mo) and post-Z11 period (April 2011-February 2014, 34 mo). We also identified the number of patients in the post-Z11 era in whom ALND was omitted as a result of Z11. Clinical and pathologic characteristics among these groups were analyzed.

RESULTS

A total of 279 and 191 ALNDs were performed in the pre-Z11 and post-Z11 groups, respectively. Variables were similar among these groups with respect to demographics, tumor characteristics, and surgeries performed. There was no difference in the monthly rates of ALND between groups-5.37 cases/mo (pre-Z11) and 5.62 cases/mo (post-Z11), P = 0.52. We identified a total of 53 patients for whom ALND was omitted due to Z11 application in the post-Z11 period, representing a potential 21.7% decrease (53/191 + 53) in the number of ALNDs in this period.

CONCLUSIONS

Although the application of Z11 could potentially impact surgical training with a 21.7% decrease in ALND cases (53/191 + 53), the surgical case volume at an academic cancer center absorbs this decrease and maintains consistent levels of training for ALND.

Preoperative axillary lymph node evaluation in breast cancer patients by breast magnetic resonance imaging (MRI): Can breast MRI exclude advanced nodal disease?

OBJECTIVES

To evaluate the diagnostic performance of breast magnetic resonance imaging (MRI) in preoperative evaluation of axillary lymph node metastasis (ALNM) in breast cancer patients and to assess whether breast MRI can be used to exclude advanced nodal disease.

METHODS

A total of 425 patients were included in this study and breast MRI findings were retrospectively reviewed. The diagnostic performance of breast MRI for diagnosis of ALNM was evaluated in all patients, patients with neoadjuvant chemotherapy (NAC), and those without NAC (no-NAC). We evaluated whether negative MRI findings (cN0) can exclude advanced nodal disease (pN2-pN3) using the negative predictive value (NPV) in each group.

RESULTS

The sensitivity and NPV of breast MRI in evaluation of ALNM was 51.3 % (60/117) and 83.3 % (284/341), respectively. For cN0 cases on MRI, pN2-pN3 manifested in 1.8 % (6/341) of the overall patients, 0.4 % (1/257) of the no-NAC group, and 6 % (5/84) of the NAC group. The NPV of negative MRI findings for exclusion of pN2-pN3 was higher for the no-NAC group than for the NAC group (99.6 % vs. 94.0 %, p = 0.039).

CONCLUSIONS

Negative MRI findings (cN0) can exclude the presence of advanced nodal disease with an NPV of 99.6 % in the no-NAC group.

KEY POINTS

• Breast MRI can be used to exclude advanced nodal disease (pN2-3). • Negative MRI allows breast cancer patients to avoid unnecessary axillary surgery (98.2 %). • Negative MRI findings exclude 99.6 % of pN2-pN3 in the no-NAC group. • Negative MRI findings exclude 96.0 % of pN2-pN3 in the NAC group.

Sentinel lymph nodes for breast carcinoma: an update on current practice

Sentinel lymph node (SLN) biopsy has been established as the standard of care for axillary staging in patients with invasive breast carcinoma and clinically negative lymph nodes (cN0). Historically, all patients with a positive SLN underwent axillary lymph node dissection (ALND). The ACOSOG Z0011 trial showed that women with T1-T2 disease and cN0 who undergo breast-conserving surgery and whole-breast radiotherapy can safely avoid ALND. The main goal of SLN examination should be to detect all macrometastases (>2 mm). Gross sectioning of SLNs at 2-mm intervals and microscopic examination of one haematoxylin and eosin-stained section from each SLN block is the preferred method for pathological evaluation of SLNs. The role and timing of SLN biopsy for patients who have received neoadjuvant chemotherapy is controversial, and continues to be explored in clinical trials. SLN biopsies from patients with invasive breast carcinoma who have received neoadjuvant chemotherapy pose particular challenges for pathologists.

Decline in Frozen Section Diagnosis for Axillary Sentinel Lymph Nodes as a Result of the American College of Surgeons Oncology Group Z0011 Trial

CONTEXT

-Results of the American College of Surgeons Oncology Group Z0011 trial showed that patients with early-stage breast cancer and limited sentinel node metastasis treated with breast conservation and systemic therapy did not benefit from axillary lymph node dissection. Subsequently, most pathology departments have likely seen a decrease in frozen section diagnosis of sentinel lymph nodes.

OBJECTIVE

-To determine the effect of the Z0011 trial on pathology practice and to examine the utility of intraoperative sentinel lymph node evaluation for this subset of patients.

DESIGN

-Pathology reports from cases of primary breast cancer that met Z0011 clinical criteria and were initially treated with lumpectomy and sentinel lymph node biopsy from 2009 to 2015 were collected. Clinicopathologic data were recorded.

RESULTS

-Sentinel lymph node biopsies sent for frozen section diagnosis occurred in 22 of 22 cases (100%) in 2009 and 15 of 22 cases (68%) in 2010 during the pre-Z0011 years, and in 3 of 151 cases (2%) collected in 2011 through 2015, considered to be post-Z0011 years. Of the 151 post-Z0011 cases, 28 (19%) had sentinel lymph nodes with metastasis, and 147 (97%) were spared axillary lymph node dissection.

CONCLUSIONS

-Following Z0011, intraoperative sentinel lymph node evaluation has significantly decreased at our institution. Prior to surgery, all patients had clinically node-negative disease. After sentinel lymph node evaluation, 97% (147 of 151) of the patients were spared axillary lymph node dissection. Therefore, routine frozen section diagnosis for sentinel lymph node biopsies can be avoided in these patients.

Two decades of axillary management in breast cancer

Background

Axillary lymph node dissection (ALND) in patients with breast cancer provides prognostic information. For many years, positive nodes were the most important indication for adjuvant systemic therapy. It was also believed that regional control could not be achieved without axillary clearance in a positive axilla. However, during the past 20 years the treatment and staging of the axilla has undergone many changes. This large population-based study was conducted in the south-east of the Netherlands to evaluate the changing patterns of care regarding the axilla, including the introduction of sentinel lymph node biopsy (SLNB) in the late 1990s, implementation of the results of the American College of Surgeons Oncology Group Z0011 study, and the initial effects of the European Organization for Research and Treatment of Cancer AMAROS study.

Methods

Data from the population-based Eindhoven Cancer Registry of all women diagnosed with invasive breast cancer in the south of the Netherlands between January 1993 and July 2014 were used.

Results

The proportion of 34 037 women staged by SLNB without completion ALND increased from 0 per cent in 1993–1994 to 69·0 per cent in 2013–2014. In the same period the proportion undergoing ALND decreased from 88·8 to 18·7 per cent. Among women with one to three positive lymph nodes, the proportion undergoing SLNB alone increased from 10·6 per cent in 2011–2012 to 37·6 per cent in 2013–2014.

Conclusion

This population-based study demonstrated the radical transformation in management of the axilla since the introduction of SLNB and following the recent publication of trials on management of the axilla with a low metastatic burden.

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.