Comment on 'Renewed interest in the progesterone receptor in breast cancer'

Can Estrogen Receptor, Progesterone Receptor, and Proliferative Index be Considered as Isolated Prognostic Factors of Overall Survival in Early luminal Breast Cancer?

BACKGROUND: There are a number of proven molecular and pathological markers important for the prognosis for OS of early luminal type breast cancer, but there are still some deficiencies mainly due to the non-linear relationship between the markers and the outcome of the disease. METHODS AND PATIENTS: In this retro-prospective study, clinical and pathological data were provided from 336 patients with breast cancer who underwent breast surgery and treatment between January 2010 and December 2013, and followed until December 2018. The aim of the study was an evaluation of ER, PR, and Ki-67 as independent prognostic factors for OS of early luminal breast cancer. RESULTS: Early luminal breast cancers were not predictive of ER expression status (p = 0.699, p = 0.356), whereas only early Luminal B was predictive for PR expression (>10%: 72.2%). Ki-67 in most of the cases of early Luminal B was with expression of >14–20% (p = 0.056). Patients with ER of 1–10% survived over 80 months (p = 0.0020) in early Luminal A, but ER expression status did not show prognostic significance for OS of early Luminal B (p = 0.775). PR status did not show prognostic significance for OS in early luminal types (p = 0.257, p = 0.622). ER >1%/PR >1% was protective in early Luminal B (p = 0.00043), but not in early Luminal A. CONCLUSION: Our results suggest ER, but not PR as independent prognostic factor for OS but only of early Luminal A. We did not prove Ki-67 as independent prognostic factor for OS of highly proliferative early breast cancer.

Biomarker phenotyping drives clinical management in axillary sentinel node: A retrospective study on women with primary breast cancer in 2002

The current study examined if cancer biomarker phenotyping could predict the clinical/pathological status of axillary nodes in women with primary breast cancer. Primary breast cancers from 2002 were analyzed for tumor size, estrogen receptor (ER), progesterone receptor (PgR), Ki-67MIB expression and Her2/neu amplification. Relationships between the clinical and pathological status of the axilla and the biological subtypes classification were analyzed using univariate, multivariate and regression tree analysis. A total of 65% of women with axillary nodes clinically involved had complete axillary node dissection (ALND) while 705 women with clinically negative axillary underwent sentinel lymph node biopsy (SLNB), 18.5% of the latter had at least one pathologically SLNB involved node. Multivariate analysis revealed that the Luminal A subtype was significantly associated (OR 0.62; P<10^-9) with clinical negative axilla while HER2pos/not Luminal was associated with clinical positivity (OR 1.71; P<0.01). No significant association between biological subtypes and SLNB status was demonstrated. Regression tree analysis revealed that subgroups with significantly different probability of SLNB status were separated according to tumor size and PgR values. In conclusion, the current study demonstrated that biomarker breast cancer phenotyping is significantly associated with clinical status of axillary nodes but not with pathological involvement of nodes at SLNB. Regression tree analysis could represent a valid attempt to individualize some patients subgroups candidate to different surgical axilla approaches.

The impact of progesterone receptor expression on prognosis of patients with rapidly proliferating, hormone receptor-positive early breast cancer: a post hoc analysis of the IBIS 3 trial

Background

In the Italian Breast Cancer Intergroup Studies (IBIS) 3 phase III trial, we compared cyclophosphamide, methotrexate, 5-fluorouracil (CMF) alone to sequential epirubicin/CMF regimens in patients with rapidly proliferating early breast cancer (RPEBC). We performed a post hoc analysis in the subgroup of patients with hormone-receptor-positive RPEBC on the prognostic role of progesterone receptor (PgR) status.

Methods

RPEBC was defined by thymidine labeling index (TLI) >3% or grade 3 or S-phase >10% or Ki67 >20%. We analyzed 466 patients with hormone-receptor-positive RPEBC receiving sequential epirubicin/CMF regimens followed by tamoxifen, and for whom the status of ER and PgR was available.

Results

Considering both cut-off values of 10% and 20%, PgR expression was significantly associated with age, menopausal status, and ER expression; HER2 status was associated with PgR status only at a cutoff value of 20% PgR. Upon univariate analysis, tumor size, nodal status, and PgR were significantly associated with disease-free survival (DFS) and overall survival (OS), while age class and local treatment type were associated only with DFS. Patients with PgR <20% showed lower 5- and 10-year DFS [hazard ratio (HR) = 1.48; 95%CI: 1.01-2.18; p = 0.044] and OS (HR = 1.85; 95%CI: 1.08-3.19, p = 0.025) rates compared with patients with PgR ⩾20%. Upon multivariate analysis, only tumor size, nodal status, and PgR were independent prognostic factors.

Conclusions

Our results highlight the independent prognostic relevance of PgR expression in patients with hormone-receptor-positive RPEBC treated with adjuvant chemotherapy and endocrine therapy, where the definition of prognostic subgroups is still a major need.