Expanding Criteria for Prognostic Stage IA in Hormone Receptor-Positive Breast Cancer

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

INTRODUCTION

With the increasing utilization of genomic assays, such as the Oncotype DX recurrence score (RS), the relevance of anatomic staging has been questioned for select older patients with breast cancer. We sought to evaluate differences in chemotherapy receipt and/or survival among older patients based on RS and sentinel lymph node biopsy (SLNB) receipt/result.

METHODS

Patients aged ≥ 65 diagnosed with pT1-2/cN0/M0 hormone-receptor-positive (HR+)/HER2-breast cancer (2010-2019) were selected from the National Cancer Database. Logistic regression was used to identify factors associated with chemotherapy receipt. Cox proportional hazards models were used to estimate the association of RS/SLNB group with overall survival. A cost-benefit study was also performed.

RESULTS

Of the 75,428 patients included, the majority had an intermediate RS (58.2% versus 27.9% low, 13.8% high) and were SLNB- (85.1% versus 11.6% SLNB+, 3.3% none). Chemotherapy was recommended for 13,442 patients (17.8%). After adjustment, chemotherapy receipt was more likely with higher RS and SLNB+. After adjustment, SLNB receipt/result was only associated with overall survival among those with an intermediate RS. However, returning to the OR for SLNB is not cost-effective.

CONCLUSIONS

SLNB receipt/result was associated with survival for those with an intermediate RS, but not a low or high RS, suggesting that an SLNB may indeed be unnecessary for select older patients with breast cancer.

Is routine axillary lymph node dissection needed to tailor systemic treatments for breast cancer patients in the era of molecular oncology? A position paper of the Italian National Association of Breast Surgeons (ANISC)

BACKGROUND

De-escalation of axillary surgery in breast cancer (BC) management began when sentinel lymph node biopsy (SLNB) replaced axillary lymph node dissection (ALND) as standard of care in patients with node-negative BC. The second step consolidated ALND omission in selected subgroups of BC patients with up to two macrometastases and recognized BC molecular and genomic implication in predicting prognosis and planning adjuvant treatment. Outcomes from the recent RxPONDER and monarchE trials have come to challenge the previous cut-off of two SLN in order to inform decisions on systemic therapies for hormone receptor-positive (HR+), human epidermal growth factor receptor type-2 (HER2) negative BC, as the criteria included a cut-off of respectively three and four SLNs. In view of the controversy that this may lift in surgical practice, the Italian National Association of Breast Surgeons (Associazione Nazionale Italiana Senologi Chirurghi, ANISC) reviewed data regarding the latest trials on this topic and proposes an implementation in clinical practice.

MATERIAL AND METHODS

We reviewed the available literature offering data on the pathological nodal status of cN0 breast cancer patients.

RESULTS

The rates of pN2 status in cN0 patients ranges from 3.5 % to 16 %; pre-surgical diagnostic definition of axillary lymph node status in cN0 patients by ultrasound could be useful to inform about a possible involvement of ≥4 lymph nodes in this specific sub-groups of women.

CONCLUSIONS

The Italian National Association of Breast Surgeons (ANISC) considers that for HR + HER2-/cN0-pN1(sn) BC patients undergoing breast conserving treatment the preoperative workup should be optimized for a more detailed assessment of the axilla and the technique of SLNB should be optimized, if considered appropriate by the surgeon, not considering routine ALND always indicated to determine treatment recommendations according to criteria of eligibility to RxPONDER and monarch-E trials.

Effectiveness of post-mastectomy adjuvant chemotherapy for the treatment of patients with prognostic stage IB breast cancer: A SEER-based study

BACKGROUND

Adjuvant chemotherapy (AC) is an important, effective treatment for breast cancer. This study evaluates the effectiveness of post-mastectomy AC in treating patients with prognostic stage IB breast cancer.

METHOD

We conducted a retrospective cohort-based study using Surveillance, Epidemiology, and End-Results database. Overall survival (OS) and breast cancer-specific survival (BCSS) were calculated using the Kaplan-Meier method. Multivariate Cox risk models were used to identify the impact of AC. Stratified analysis was performed according to molecular subtypes, anatomic stages, and other risk factors to evaluate the effect of AC on survival.

RESULTS

28,825 women diagnosed with prognostic stage IB breast cancer were included. The 5-year OS was significantly higher in AC group than in non-adjuvant chemotherapy (NAC) group (P < 0.0001); however, the 5-year BCSS in AC group was significantly lower than in NAC group (P = 0.039). Multivariate analysis revealed that AC was a favorable prognostic factor for OS (P < 0.001), but not BCSS (P = 0.407). AC was not an independent prognostic factor for BCSS in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR[+]/HER2[-]) subtype or pT1a-1b/N0-1 stage with HER2 overexpression (HER2[+]) subtype, regardless of whether HR was positive or negative (P > 0.05). Meanwhile, AC is not an independent prognostic factor for OS and BCSS in patients with lymph node micrometastases.

CONCLUSION

Our study demonstrates that patients with prognostic stage IB do not fully benefit from AC. Individualized treatment management is required for patients with pT1a-1b/N0-1 tumors, lymph node micrometastases, or HR(+)/HER2(-) subtypes.

Expanding the Staging Criteria for T1-2N0 Hormone-Receptor Positive Breast Cancer Patients Enrolled in TAILORx

BACKGROUND

The American Joint Committee on Cancer (AJCC) 8th edition pathologic prognostic staging (PPS) incorporates anatomic and biologic factors. The OncotypeDX Breast Recurrence Score (RS) was included based on the initial report of the TAILORx trial, with T1-2N0 hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer patients who had a RS < 11 staged as PPS 1A. This study examined whether the RS criteria for PPS 1A can be further expanded using patients enrolled in the TAILORx trial.

METHODS

The TAILORx trial enrolled 10,273 HR+HER2- T1-2N0 patients. Those with incomplete HR-status/grade and T3 disease were excluded for analysis. The recurrence-free interval (RFI) was compared between the patients who did and those who did not fall into the current PPS 1A category using the Kaplan-Meier method.

RESULTS

The study enrolled 9535 patients for analysis. The RS was < 11 in 16.1%, 11-17 in 35.9%, 18-25 in 32.4%, and > 25 in 15.6% of the patients. The majority (91.2%) of the patients (including all the T1N0 patients regardless of RS) were PPS 1A, and 8.8% were not-PPS 1A. The median follow-up time was 95 months. The PPS 1A patients had an 8-year RFI of 94.2%, which was similar to that of the patients with a RS of 11-17 who were not-PPS 1A (91.7%; p = 0.07) and better than that of the patients with a RS ≥ 18 who were not-PPS 1A (85.4% for a RS of 18-25, 76.0% for a RS > 25; both p < 0.01). Similar RFI trends were seen in patients who received endocrine therapy or chemotherapy followed by endocrine therapy.

CONCLUSIONS

Patients with T1-2N0 HR+HER2- breast cancer and a RS < 18 have an RFI similar to that of patients staged as PPS 1A by the current AJCC staging system, regardless of treatment, suggesting that the criteria for PPS 1A can be expanded to include a RS < 18.

Sentinel Lymph Node Biopsy Alone is Adequate for Chemotherapy Decisions in Postmenopausal Early-Stage Hormone-Receptor-Positive, HER2-Negative Breast Cancer with One to Three Positive Sentinel Lymph Nodes

BACKGROUND

The RxPONDER trial randomized patients with cT1-3N0 hormone receptor-positive, HER2-negative (HR⁺HER2^-) breast cancer and one to three positive nodes and Recurrence Score (RS) < 26 to endocrine therapy (ET) or chemoendocrine therapy (CET) with equivalent survival in postmenopausal women. In current practice, cN0 patients with one or two positive sentinel lymph nodes (SLN) do not undergo axillary lymph node dissection (ALND), raising concerns about applying these data in patients who may have additional nodal disease.

METHODS

We identified institutional [Dana-Farber Brigham Cancer Center (DF/BCC), 2016-2020] and national [National Cancer Database (NCDB), 2012-2017] cohorts of women aged 50-75 years with cT1-3N0 HR⁺HER2^- breast cancer and RS < 26 treated with upfront surgery with one to three positive SLN. Axillary nodal burden and outcomes were assessed on the basis of the number of positive nodes and CET use.

RESULTS

A total of 197 and 13,499 HR⁺HER2^- eligible patients with one to three positive SLN and RS < 26 were identified in the DF/BCC and NCDB databases, respectively, and 12.7% of DF/BCC and 32.4% of NCDB patients had ALND. Of these, only 12.0 and 4.9% had more than three total positive nodes, respectively. Rates of CET were 6.6% in DF/BCC and 20.9% in NCDB patients. In the NCDB, similar adjusted 4-year overall survival was seen between patients treated with CET or ET for any number of positive nodes (98.1-99.9%, all p > 0.05).

CONCLUSIONS

Postmenopausal women with cT1-3N0 HR⁺HER2^- breast cancer and RS < 26 with one to three positive SLN are unlikely to have more than three total positive nodes. CET decisions should continue to be based on SLN biopsy as ALND is unlikely to change treatment recommendations or outcomes.