Do T1a breast cancers profit from adjuvant systemic therapy? A multicenter retrospective cohort study of 325 T1a-patients

A comparison of local therapy alone with local plus systemic therapy for stage I pT1aN0M0 HER2+ breast cancer: A National Cancer Database analysis

BACKGROUND

Small invasive breast cancers (BCs) with tumor sizes ≤5 mm (T1a) are associated with an excellent prognosis without systemic therapy. Although HER2 overexpression (HER2+) is associated with a higher risk of recurrence and poorer clinical outcomes, in the absence of HER2 directed therapy, it remains unclear whether adjuvant systemic therapy is necessary in node-negative patients diagnosed with HER2+ invasive BCs ≤5 mm (pT1aN0M0).

METHODS

The National Cancer Database was searched to identify patients diagnosed with HER2+ pT1aN0M0 BCs from 2004 to 2017. The cohort was stratified by treatment status: local therapy alone or local plus adjuvant systemic therapy. A 1:1 propensity match was performed. Overall survival (OS) was analyzed using stratified multivariable Cox proportional hazards regression analyses.

RESULTS

Of the 8948 patients found, 4026 (45.0%) underwent surgery alone, and 4922 (55.0%) received surgery plus systemic therapy. Patients with either moderately differentiated (odds ratio [OR], 2.053; P < .001) or poorly/undifferentiated tumors (OR, 3.780; P < .001) or with the presence of lymphovascular invasion (OR, 3.351; P < .001) were more likely to have received systemic therapy. Propensity matching generated 1162 pairs of patients who were hormone receptor positive (HR+) and 748 pairs who were hormone receptor negative (HR-). Propensity matching effectively reduced selection bias between study groups. In the matched cohort, the addition of systemic therapy was not associated with superior OS (hazard ratio for HR+, 1.613; P = .107, and hazard ratio for HR- 1.319; P = .369) compared with patients who received local therapy alone.

CONCLUSIONS

In pT1aN0M0 HER2+ BC, the addition of adjuvant systemic therapy after surgical excision was not associated with improved OS compared with local therapy alone.

The Role of Trastuzumab in Patients with HER2 Positive Small (pT1mi/a) Breast Cancers, a Multicenter Retrospective Study

Simple Summary

Treatment of small HER2+ breast cancers with adjuvant Trastuzumab is still controversial. This study aims to measure the effect of Trastuzumab in early stages of breast cancer (pT1mic/a pN0/1mi) in terms of disease recurrence and to identify which factors most affect the prognosis of small HER2+ tumors. We retrospectively selected and reviewed 100 HER2+ pT1mic-pT1a breast cancer patients with a median follow-up of 86 months. In our study the primary outcome was the disease recurrence rate, which appeared to be significantly lower among patients who received adjuvant Trastuzumab. Among the patients who did not receive adjuvant Trastuzumab, HR− HER2+ tumors showed a risk seven times higher of relapse. The results of our study indicate that adjuvant Trastuzumab reduces the risk of developing a disease recurrence even in small HER2+ tumors. Adjuvant targeted therapy should be considered in patients with HR− HER2+ tumors, the category with the highest risk of recurrence.

Abstract

The treatment with adjuvant Trastuzumab in patients diagnosed with HER2+ small breast cancers is controversial: limited prospective data from randomized trials is available. This study aims to measure the effect of Trastuzumab in the early stages of breast cancer (pT1mic/a pN0/1mi) in terms of disease recurrence and to identify which are the factors that most affect the prognosis of small HER2+ tumors. One hundred HER2+ pT1mic-pT1a breast cancer patients who were treated in three Turin Breast Units between January 1998 and December 2018 were retrospectively selected and reviewed. Trastuzumab was administered to 23 patients. Clinicopathological features and disease-free survival (DFS) were compared between different subgroups. The primary outcome was the disease recurrence rate. Median follow-up time was 86 months. Compared to pT1a tumors, pT1mic lesions had a higher tumor grade (84% of pT1mic vs. 55% of pT1a; p = 0.003), a higher Ki-67 index (81% vs. 46%; p = 0.007) and were more frequently hormone receptor (HR) negative (69% vs. 36%, p = 0.001). Disease recurrence rate was significantly lower among patients who received adjuvant Trastuzumab (p = 0.02), with this therapy conferring an 85% reduction in the risk of relapse (HR 0.15; p = 0.02). Among the patients who did not receive adjuvant Trastuzumab, the only factor significantly associated with an increased risk of developing a recurrence was the immunohistochemical (IHC) subtype: in fact, HR− HER2+ tumors showed a risk seven times higher of relapsing (HR 7.29; p = 0.003). Adjuvant Trastuzumab appears to reduce the risk of disease recurrence even in small HER2+ tumors. The adjuvant targeted therapy should be considered in patients with HR− HER2+ tumors since they have the highest risk of recurrence, independently from size and grade.

Clinicopathologic features of unexpectedly HER2 positive breast carcinomas: An institutional experience

Human epidermal growth factor receptor 2 (HER2) overexpression occurs in 15-20 % of all breast carcinomas. These tumors are usually high-grade which often correlates with reduced overall survival and increased rates of recurrence. In a retrospective review, we identified 19 cases of unexpectedly HER2 positive (by immunohistochemistry and/or fluorescence in-situ hybridization) invasive breast carcinomas on core needle biopsies from a registry at Northwestern Memorial Hospital. These cases included low-grade tumors, invasive lobular carcinomas, classic type, and invasive carcinomas with special subtype features. Twelve of the tumors were histologic grade 1 and 7 were histologic grade 2. One of the grade 1 tumors had tubular features (8 %), 1 had cribriform features (8 %), 2 had mucinous features (17 %), 2 were invasive lobular carcinomas, classic type (17 %), and the rest were invasive carcinoma, no special type (50 %). The histologic grade 2 tumors included 5 invasive lobular carcinomas, classic type (71 %) and 2 invasive ductal carcinomas with mucinous features (29 %). By immunohistochemistry, 13 (65 %) were HER2 score 3+, 7 were score 2+ (35 %), and reflex fluorescence in-situ hybridization (FISH) testing showed amplification in 6 cases, with 1 equivocal case amplified on excision. Despite the HER2 positive status in the selected cases, no unique morphologic features that would indicate aggressive behavior were identified. In clinical follow up, two patients were found to have recurrences, five had lymph node metastasis, and one had distant metastasis. None of the patients with recurrent disease were treated with trastuzumab, despite their positive HER2 results. These findings support that our population of HER2 positive carcinomas showed a similar rate of lymph node metastases and recurrence as poorly-differentiated tumors, supporting HER2 positivity as a poor prognostic indicator, irrespective of morphologic features. We recommend continuing to test all breast cancers, regardless of grade or special subtype features, to provide the most comprehensive treatment and prognostic information for both clinicians and patients.

Characteristics and clinical outcome of pT1a-b node-negative breast cancer

OBJECTIVE:

Tumor size, along with other clinicopathological characteristics, has a prognostic role in breast cancer. Recurrence risk tends to rise as tumor size increases. Early T-stage portends a good prognosis. We aimed to investigate the recurrence-free interval rates of T1abN0 group of early breast cancer.

METHODS:

Patients diagnosed with pT1a and T1b, lymph node metastasis-negative breast cancer were included in the study. Clinicopathologic characteristics including recurrence, distant metastasis, and final status of the patients were obtained retrospectively from the patient files.

RESULTS:

A total of 84 patients included. Twenty-six patients (31%) had T1a and 58 patients (69%) had T1b tumors. The 5-year distant relapse-free survival (DRFS) rate of T1ab tumors was 95.2%. The DRFS rate of T1a tumors was 96.2%, while the rate of T1b tumors was 94.8% (p=0.555). The 5-year RFS rate of T1ab tumors was 90.5%. The RFS rate of T1a tumors was 84.6%, whereas the rate of T1b tumors was 93.1% (p=0.359). The 5-year DRFS rate of hormone receptor positive group was 97%, Her-2 positive group was 81.8%, and triple negative group was 100% (p=0.041). The 5-year RFS rate of the hormone receptor positive group was 97%, Her-2 positive group was 72.7%, and triple negative group was 57.1% (p=0.001).

CONCLUSION:

The results of the study provided that both T1a and T1b tumors have a good and similar prognosis.

T1a triple negative breast cancer has the worst prognosis among all the small tumor (<1 cm) of TNBC and HER2-rich subtypes

Background

Triple negative breast cancer (TNBC), accounting for 15% of all breast cancer cases, was usually considered as the most aggressive subtype. The present study evaluated the prognosis of T1a TNBC and the impact of tumor size on T1 TNBC survival in large-scale population.

Methods

This retrospective study enrolled T1a/T1b/T1c TNBC and HER2⁺/hormone receptor (HoR)^- patients diagnosed between 2010 to 2012 from the Surveillance, Epidemiology, and End Results database. The following information was extracted for further analyses: demographic variables including age at diagnosis, race, marital status, laterality, histological grade, T/N stage, American Joint Committee on Cancer (AJCC) stage, radiation therapy, survival and cause of death. Kaplan-Meier method and Cox regression were engaged for breast cancer specific survival (BCSS) and overall survival (OS) analyses.

Results

In all, the present study enrolled 6,953 TNBC and 2,648 HER2⁺/HoR^- patients. T1a TNBC which generally omitted adjuvant chemotherapy had worse prognosis than T1a HER2⁺/HoR^- [BCSS: hazard ratio (HR) 3.23, 95% confidence interval (CI): 1.05-9.09, P=0.03; OS: HR 2.63, 95% CI: 1.25-5.56, P=0.01] and T1b HER2⁺/HoR^- (BCSS: HR 5.26, 95% CI: 1.61-16.7, P=0.006; OS: HR 3.03, 95% CI: 1.27-7.14, P=0.013) tumors which both were recommended by the National Comprehensive Cancer Network (NCCN) guideline to have chemotherapy. T1a TNBC also showed a trend with poorer prognosis than T1b TNBC, but did not reach statistical significance.

Conclusions

T1a TNBC had the worst prognosis among all small tumors (<1 cm) of TNBC and HER2⁺/HoR^- subtypes, indicating the necessity of more intensive adjuvant treatment.

The Evolving Complexity of Treating Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor-2 (HER2)-Negative Breast Cancer: Special Considerations in Older Breast Cancer Patients-Part I: Early-Stage Disease

The median age for breast cancer diagnosis is 62 years, but a disproportionate number of patients are over the age of 75 years and the majority of those have hormone receptor-positive, human epidermal growth factor receptor-2 (HER2)-negative cancers. This review provides a logical algorithm to guide providers through the many complicated issues involved in adjuvant systemic therapy decisions in older patients with hormone receptor-positive, HER2-negative breast cancer. For this subtype of breast cancer, the mainstay of treatment is surgery and adjuvant endocrine therapy with tamoxifen or an aromatase inhibitor (AI). Adjuvant chemotherapy is added to the treatment regimen when the benefits of treatment are deemed to outweigh the risks, making the risk-benefit discussion particularly important in older women. Traditional tools for cancer risk assessment and genomic expression profiles (GEPs) are under-utilized in older patients, but yield equally useful information about cancer prognosis as they do in younger patients. Additionally, there are tools that estimate life-limiting toxicity risk from chemotherapy and life expectancy, which are both important issues in the risk-benefit discussion. For very low-risk cancers, such as non-invasive and small lymph node (LN)-negative cancers, the benefits of any adjuvant therapy is likely outweighed by the risks, but endocrine therapy might be considered to prevent future new breast cancers. For invasive tumors that are > 5 mm (T1b or larger) or involve LNs, adjuvant endocrine therapy is recommended. Generally, AIs should be included, though tamoxifen is effective and should be offered when AIs are not tolerated. Bone-preserving agents and high-dose vitamin D are options to preserve bone density or treat osteoporosis, especially in older women who are taking AIs. Where the risk-reducing benefit from adjuvant chemotherapy outweighs the toxicity risk, adjuvant chemotherapy should be considered. Adjuvant chemotherapy has similar benefits in older and younger patients and standard regimens are preferred. Several exciting clinic trials are underway and have included older patients, including those adding molecularly targeted agents, cyclin-dependent kinase (CDK) 4/6 inhibitors and everolimus, to endocrine therapy in the adjuvant setting. The high incidence of breast cancer in older women should drive us to design clinical trials for this population and emphasize their inclusion in ongoing trials as much as possible.

Does the number of removed axillary lymphnodes in high risk breast cancer patients influence the survival?

Background

The decision making process for axillary dissection has changed in recent years for patients with early breast cancer and positive sentinel lymph nodes (LN). The question now arises, what is the optimal surgical treatment for patients with positive axillary LN (pN+). This article tries to answer the following questions:

Is there a survival benefit for breast cancer patients with 3 or more positive LN (pN3+) and with more than 10 removed LN?

Is there a survival benefit for high risk breast cancer patients (triple negative or Her2 + breast cancer) and with 3 or more positive LN (pN3+) with more than 10 removed LN?

In pN + patients is the prognostic value of the lymph node ratio (LNR) of pN+/pN removed impaired if 10 or less LN are removed?

Methods

A retrospective database analysis of the multi center cohort database BRENDA (breast cancer under evidence based guidelines) with data from 9625 patients from 17 breast centers was carried out. Guideline adherence was defined by the 2008 German National consensus guidelines.

Results

2992 out of 9625 patients had histological confirmed positive lymph nodes. The most important factors for survival were intrinsic sub types, tumor size and guideline adherent chemo- and hormonal treatment (and age at diagnosis for overall survival (OAS)). Uni-and multivariable analyses for recurrence free survival (RFS) and OAS showed no significant survival benefit when removing more than 10 lymph nodes even for high-risk patients. The mean and median of LNR were significantly higher in the pN+ patients with ≤10 excised LN compared to patients with > 10 excised LN. LNR was in both, uni-and multivariable, analysis a highly significant prognostic factor for RFS and OAS in both subgroups of pN + patients with less respective more than 10 excised LN. Multivariable COX regression analysis was adjusted by age, tumor size, intrinsic sub types and guideline adherent adjuvant systemic therapy.

Conclusion

The removal of more than 10 LN did not result in a significant survival benefit even in high risk pN + breast cancer patients.