Prognosis and Outcome of Small (≤1 cm), Node-Negative Breast Cancer on the Basis of Hormonal and HER-2 Status

Abstract

Long-term outcomes and hence the role of adjuvant therapy in patients with small (<1 cm), node-negative breast cancer remain unclear. This study's objective was to evaluate whether human epidermal growth factor receptor (HER)-2 status is an independent, poor prognostic marker in patients with these tumors and to identify a subgroup of patients with these small tumors who might benefit from adjuvant systemic therapy. All patients with a diagnosis of a node-negative breast tumor measuring <1 cm and available HER-2 test results between January 1, 2001, and December 31, 2005, at the three Mayo Clinic sites were identified. Clinicopathologic data were compared in three groups: HER-2 ؊ , HER-2 ؉ , and triple-negative (TN) tumors. Of the 421 tumors identified, 364 (86.5%) were HER-2 ؊ , 28 (6.7%) were HER-2 ؉ , and 29 (6.9%) were TN. The median follow-up time was 1,015 days (range, 1-2,549 days). Groups were balanced in terms of patient age and tumor histology. Eleven patients with HER-2؊ tumors (3.0%), seven with HER-2 ؉ tumors (25.0%), and eight with TN tumors (27.6%) received adjuvant chemotherapy. Follow-up data were available for 357, 28, and 28 patients in the three groups, respectively. Death rates in the three groups were 6.4% (23 of 357) (one recurrencerelated death), 0% (0 of 28), and 7.1% (2 of 28) (one recurrence-related death), respectively. During followup, the tumor recurred in nine patients: four were HER-2 ؊ tumors (1.1%), two were HER-2 ؉ tumors (7.1%), and three were TN tumors (10.7%). Patients with small, node-negative breast tumors have an excellent prognosis, but HER-2 ؉ and TN tumors appear to have a higher recurrence rate, warranting consideration for broad use and optimization of systemic adjuvant treatments. The Oncologist

Chemotherapy Use and Surgical Treatment by Receptor Subtype in Node-Negative T1a and T1b Female Breast Cancers, Iowa SEER Registry, 2010- to 2012

“…The percent of HER2-positive and TNBC tumors seen are consistent with other series. 18,26,27 The majority of these small HER2-positive tumors in Iowa were also HR-positive. This is consistent with other series looking at T1a,bN0M0 tumors.…”

“…This is consistent with other series looking at T1a,bN0M0 tumors. 16,27,28 Broadly, treatment with chemotherapy correlated with factors associated with risk of systemic disease recurrence. Mastectomy rates for these small tumors were even higher than seen in other recent reported series.…”

Small breast cancers: When and how to treat

“…The efficacy of administering adjuvant systemic therapy, particularly CT, in 'small' node negative BC is still a controversial issue [3]. The crucial role of biological characteristics such as molecular phenotype must be taken into account for treatment decision making in this population.…”

“…Although adjuvant systemic therapy is now routinely recommended for patients with nodepositive breast cancer (BC) or node-negative tumors larger than 1 cm, its role in subcentimetric node-negative BC has to be better defined. Accumulating data from the use of biological markers and multi-gene prognosticators in treatment decision indicate that traditional clinical factors, such as size and nodal status, isolated are not enough to accurately prognosticate BC; additionally, these data raise the question whether patients with subcentimetric node-negative BC derive enough benefit from adjuvant chemotherapy (CT) to outweigh the risks of treatment [2,3].…”

“…Consequently, the benefits gained with newer adjuvant therapies have not been well defined for these BC patients. Recurrences and deaths do occur in some patients with T1N0M0 tumors [3]. Furthermore, accumulating evidence regarding the underlying biology of aggressive subtypes indicates that it has prognostic value independently from tumor burden (i.e.…”