Cost-effectiveness of Choosing Wisely guidelines for axillary observation in women older than age 70 years with hormone receptor-positive, clinically node-negative, operable breast tumors

Recent Advances in the Upfront Surgical Management of the Axilla in Patients with Breast Cancer

Nodal status is an important prognostic indicator. Upfront axillary surgery for patients with breast cancer has historically been both diagnostic and therapeutic-serving to determine nodal status and inform adjuvant therapies, and to remove clinically significant disease. However, trials of de-escalation or omission of axillary surgery altogether consistently demonstrate noninferior oncologic outcomes in a wide variety of patient subsets. These strategies also reduce the morbidity associated with either sentinel lymphadenectomy or axillary lymph node dissection. Here we will briefly review landmark trials that have shaped upfront axillary surgery as well as recent advances, and discuss areas of ongoing investigation and future needs.

Physician-level variation in axillary surgery in older adults with T1N0 hormone receptor-positive breast cancer: A retrospective population-based cohort study

INTRODUCTION

We sought to determine how considerations specific to older adults impact between- and within-surgeon variation in axillary surgery use in women ≥70 years with T1N0 HR+ breast cancer.

MATERIALS AND METHODS

Females ≥70 years with T1N0 HR+/HER2-negative breast cancer diagnosed from 2013 to 2015 in SEER-Medicare were identified and linked to the American Medical Association Masterfile. The outcome of interest was axillary surgery. Key patient-level variables included the Charlson Comorbidity Index (CCI) score, frailty (based on a claims-based frailty index score), and age (≥75 vs <75). Multilevel mixed models with surgeon clusters were used to estimate the intracluster correlation coefficient (ICC) (between-surgeon variance), with 1-ICC representing within-surgeon variance.

RESULTS

Of the 4410 participants included, 6.1% had a CCI score of ≥3, 20.7% were frail, and 58.3% were ≥ 75 years; 86.1% underwent axillary surgery. No surgeon omitted axillary surgery in all patients, but 42.3% of surgeons performed axillary surgery in all patients. In the null model, 10.5% of the variance in the axillary evaluation was attributable to between-surgeon differences. After adjusting for CCI score, frailty, and age in mixed models, between-surgeon variance increased to 13.0%.

DISCUSSION

In this population, axillary surgery varies more within surgeons than between surgeons, suggesting that surgeons are not taking an "all-or-nothing" approach. Comorbidities, frailty, and age accounted for a small proportion of the variation, suggesting nuanced decision-making may include additional, unmeasured factors such as differences in surgeon-patient communication.

A Prospective Study of Sentinel Node Biopsy Omission in Women Age ≥ 65 Years with ER+ Breast Cancer

BACKGROUND

National guidelines recommend omitting SNB in older patients with favorable invasive breast cancer. However, there is a lack of prospective data specifically addressing this issue. This study evaluates recurrence and survival in estrogen receptor-positive/Her2- (ER+) breast cancer patients, aged ≥ 65 years who have breast-conserving surgery (BCS) without SNB.

METHODS

This is a prospective, observational study at a single institution where 125 patients aged ≥ 65 years with clinical T1-2N0 ER+ invasive breast cancer undergoing BCS were enrolled. Patients were treated with BCS without SNB. Primary outcome measure was axillary recurrence. Secondary outcome measures include recurrence-free survival (RFS), disease-free survival (DFS), breast cancer-specific survival (BCSS), and overall survival (OS).

RESULTS

From January 2016 to July 2022, 125 patients were enrolled with median follow-up of 36.7 months [95% confidence interval (CI) 35.0-38.0]. Median age was 77.0 years (range 65-93). Median tumor size was 1 cm (range 0.1-5.0). Most tumors were ductal (95/124, 77.0%), intermediate grade (60/116, 51.7%), and PR-positive (117/123, 91.7%). Radiation therapy was performed in 37 of 125 (29.6%). Only 60 of 125 (48.0%) who were recommended hormonal therapy were compliant at 2 years. Chemotherapy was administered to six of 125 (4.8%) patients. There were two of 125 (1.6%) axillary recurrences. Estimated 3-years rates of regional RFS, DFS, and OS were 98.2%, 91.2%, and 94.8%, respectively. Univariate Cox regression identified hormonal therapy noncompliance to be significantly associated with recurrence (p = 0.02).

CONCLUSIONS

Axillary recurrence rates were extremely low in this cohort. These results provide prospective data to support omission of SNB in this patient population TRIAL REGISTRATION: ClinicalTrials.gov ID NCT02564848.

Sentinel lymph node biopsy in women over 70: Evaluation of rates of axillary staging and impact on adjuvant therapy in elderly women

BACKGROUND

The 2016 Society of Surgical Oncology Choosing Wisely guidelines recommended against routine sentinel lymph node biopsy in women ≥70 years old with favorable, early-stage breast cancer, as sentinel lymph node biopsy does not decrease recurrence or mortality in these patients. This study's objective was to evaluate the use of sentinel lymph node biopsy and its effect on management in elderly patients.

METHODS

A retrospective analysis of female patients ≥70 years old with stage I-II, clinically node-negative, hormone-receptor positive, HER2-negative disease undergoing upfront breast cancer surgery between 2017 and 2019. Primary outcome was rate of sentinel lymph node biopsy. Secondary outcome was effect of sentinel lymph node biopsy on adjuvant therapy.

RESULTS

In total, 142 patients were included. Median age was 76 (interquartile range 73-81), and 71.8% underwent lumpectomy. On final pathology, 57.7% had invasive ductal carcinoma, and median tumor size was 15 mm (interquartile range 10-24.3). A total of 118 patients (83.1%) underwent sentinel lymph node biopsy; of these, 27 (22.9%) were positive for N1mi (7 patients) or N1a disease (20 patients). On multivariate regression analysis, patients undergoing sentinel lymph node biopsy were more likely to be younger (odds ratio 0.87, 95% confidence interval 0.78-0.95). The major risk factor for sentinel lymph node biopsy positivity was lymphovascular invasion (odds ratio 13.4, 95% confidence interval 4.57-40.1). Patients with sentinel lymph node biopsy positivity were more likely to receive local adjuvant radiation therapy (odds ratio 4.66, 95% confidence interval 1.49-16.8) and tended to receive more adjuvant regional radiation therapy (75.0% if sentinel lymph node biopsy positive compared with 15.3% if sentinel lymph node biopsy negative, P < .001).

CONCLUSION

Despite the 2016 Choosing Wisely guidelines, more than 80% of patients ≥70 years old underwent sentinel lymph node biopsy at our institution. If sentinel lymph node biopsy was positive, this is associated with over 4-fold higher rates of adjuvant radiation therapy.