Rassegna della letteratura – aprile 2019

Biologia, genetica, laboratorio e anatomia patologica

Mukhopadhyay UK, Oturkar CC et Al. – TP53 Status as a Determinant of Pro- versus Anti-tumorigenic Effects of Estrogen Receptor-beta in Breast Cancer – J Natl Cancer Inst. 2019 Apr 16. pii: djz051. doi: 10.1093/jnci/djz051.

Background: Anti-tumorigenic versus pro-tumorigenic roles of estrogen receptor-beta (ESR2) in breast cancer (BC) remain unsettled. We investigated the potential of TP53 status to be a determinant of the bi-faceted role of ESR2 and associated therapeutic implications for triple negative BC (TNBC).

Methods: ESR2-TP53 interaction was analyzed with multiple assays including in situ proximity ligation assay (PLA). Transcriptional effects on TP53-target genes and cell proliferation in response to knocking down or overexpressing ESR2 were determined. Patient survival according to ESR2 expression levels and TP53 mutation status was analyzed in the Basal-like/ TNBC subgroup in METABRIC (n = 308) and Roswell (n = 46) patient cohorts by univariate Cox regression and log-rank test. All statistical tests are two-sided.

Results: ESR2 interaction with WT and mutant TP53 caused pro-proliferative and anti-proliferative effects, respectively. Depleting ESR2 in cells expressing WT TP53 resulted in increased expression of TP53-target genes CDKN1A (control group mean = 1 [SD = 0.13] vs ESR2 depletion group mean =2.08 [SD = 0.24]; p=.003) and BBC3 (control group mean = 1 [SD = 0.06] vs ESR2 depleted group mean =1.92 [SD = 0.25]; p=.003); however expression of CDKN1A (control group mean = 1 [SD = 0.21] vs ESR2 depleted group mean =0.56 [SD = 0.12];p=.02) and BBC3 (control group mean = 1 [SD = 0.03] vs ESR2 depleted group mean =0.55 [SD = 0.09]; p = .008) was decreased in cells expressing mutant TP53. Overexpressing ESR2 had opposite effects. Tamoxifen increased ESR2-mutant TP53 interaction leading to reactivation of TP73 and apoptosis. High levels of ESR2 expression in mutant TP53- expressing Basal-like tumors is associated with better prognosis (METABRIC cohort: log-rank p = 0.001; HR = 0.26, 95% Confidence interval= 0.08 to 0.84, univariate Cox p = 0.02).

Conclusions: TP53 status is a determinant of the functional duality of ESR2. Our study suggests that ESR2-mutant TP53 combination prognosticates survival in TNBC revealing a novel strategy to stratify TNBC for therapeutic intervention potentially by repurposing tamoxifen

Tonellotto F, Bergmann A et Al – Impact of Number of Positive Lymph Nodes and Lymph Node Ratio on Survival of Women with Node-Positive Breast Cancer. – Eur J Breast Health. 2019 Apr 1;15(2):76-84. doi: 10.5152/ejbh.2019.4414.

Background: This study aimed to evaluate the association of axillary lymph node ratio (LNR) and number of positive lymph nodes (pN) with the risk of breast cancer recurrence and death.

Methods: A retrospective cohort study of node-positive stage II and III breast cancer patients diagnosed and treated between 2008 and 2009 at the Brazilian National Cancer Institute (INCA), Brazil. Overall and disease-free survival curves for number of positive lymph nodes (pN) and lymph node ratio (LNR) risk groups were constructed using the Kaplan-Meier method and compared by the log-rank test. Multivariate analysis was performed using stepwise forward Cox regression models

Results: In total, 628 women with node-positive breast cancer were included. Most patients (69.5%) had advanced clinical stage tumors (≥IIB). The median follow-up was 58 months (range: 3-92 months). The adjusted recurrence hazard of pN2 and pN3 patients was 2.47 (95% Confidence Interval [CI] 1.72-3.56) and 2.42 (1.62-3.60), respectively, compared to pN1 patients (p<0.001), while the hazard of intermediate (0.21-0.65) and high-risk (>0.65) LNR was 2.11 (1.49-3.00) and 3.19 (2.12-4.80), respectively, compared to low-risk LNR (≤0.20) patients (p<0.001). On the other hand, the hazard of death of pN2 and pN3 patients was 2.17 (1.42-3.30) and 2.41 (1.53-3.78), respectively (p<0.001), and the hazard of intermediate (0.21-0.65) and high-risk (>0.65) LNR patients was 1.70 (1.13-2.56) and 2.74 (1.75-4.28), respectively (p≤0.001).

Conclusions: Higher pN and LNR were associated with shorter disease-free survival and overall survival times.

Zhao Y, Wang X et Al. – Response to immunohistochemical markers’ conversion after neoadjuvant chemotherapy in breast cancer patients: association between imaging and histopathologic analysis. – Clin Transl Oncol. 2019 Apr 20. doi: 10.1007/s12094-019-02112-z

Background: Breast ultrasound and mammography were used in the detection of residual tumor after neoadjuvant chemotherapy. The aim of this study was to evaluate the correlation between clinical and pathological responses with breast density and IHC marker conversion to understand how this information might be used in the future to direct treatment

Methods: We included 119 patients who underwent CNB and followed NACT. The breast density assessment was based on the mammography examination performed at the time of diagnosis. We evaluated the clinical and pathological responses to NACT by the UICC and Miller-Payne grading systems, respectively.

Results: Of 119 patients who met the inclusion criteria, patients with high pre-treatment IHC markers levels showed higher expression of IHC markers regardless of the post-treatment IHC marker level at baseline. However, breast and node tumor sizes before and after NACT were negatively correlated with hormone receptor conversion and positively correlated with Ki-67 conversion (P < 0.05). Patients with low BD were more likely to have a cCR, pCR, TNBC, and postmenopausal status than those with a high BD (P < 0.05). BD was significantly associated with PR and Ki67 conversion but not ER conversion.

Conclusions: Our prospective observational study demonstrated that IHC marker conversion could be used to identify lesion size changes and BD. We also found that a high BD was linked to clinical and pathological responses, molecular subtype, and menopausal status. In the future, additional studies are required to validate the predictive value identified by this research.

Caziuc A, Schlanger D et Al. – Can Tumor-Infiltrating Lymphocytes (TILs) Be a Predictive Factor for Lymph Nodes Status in Both Early Stage and Locally Advanced Breast Cancer? – J Clin Med. 2019 Apr 22;8(4). pii: E545. doi: 10.3390/jcm8040545.

Background: The status of axillary lymph nodes is an important prognostic factor in the outcome of breast cancer tumors. New trials changed the attitude towards axillary clearance. In the era of development of new immune therapies for breast cancer, it is important to identify a biomarker that can predict lymph node status. Tumor-infiltrating lymphocytes (TILs) are a valuable indicator of the immune microenvironment that plays the central role in new anticancer drugs. Although the correlation between TILs and response to chemotherapy was established by previous studies, our retrospective study investigated the correlation between TILs and lymph node status. We analyzed data on 172 patients. According to stage, patients were divided in two groups: patients who underwent primary surgical treatment (breast-conserving or mastectomy and sentinel lymph node (SLN) biopsy +/- axillary clearance in conformity with lymph node status) and patients who received chemotherapy prior to surgical treatment (breast-conserving or mastectomy + axillary clearance). We showed a good inverse correlation between TILs and lymph nodes status for both early stage and locally advanced breast cancers. Moreover, TILs are a predictor for positive lymph nodes in the axilla in patients undergoing axillary clearance after SLN biopsy, with no statistical difference between the intrinsic or histological subtype of breast cancers. We also obtained a significant correlation between TILs and response to chemotherapy with no significative difference according to histological subtype. Although further data have still to be gathered before meeting the criteria for clinical utility, this study demonstrates that TILs are one of the most accredited forthcoming biomarkers for breast cancer (BC) patients.

Leung SCY, Nielsen TO et Al. – Analytical validation of a standardized scoring protocol for Ki67 immunohistochemistry on breast cancer excision whole sections: an international multicenter collaboration. – Histopathology. 2019 Apr 24. doi: 10.1111/his.13880

Background: The nuclear proliferation marker Ki67 assayed by immunohistochemistry has multiple potential uses in breast cancer, but an unacceptable level of inter-laboratory variability has hampered its clinical utility. The International Ki67 in Breast Cancer Working Group has undertaken a systematic program to determine whether Ki67 measurement can be analytically validated and standardized across laboratories. This study addresses whether acceptable scoring reproducibility can be achieved on excision whole sections.

Methods: Adjacent sections from 30 primary ER+ breast cancers were centrally stained for Ki67 and sections were circulated among 23 pathologists in 12 countries. All pathologists scored Ki67 by two methods: (a) global: 4 fields of 100 tumor cells each were selected to reflect observed heterogeneity in nuclear staining; (b) hot-spot: the field with highest apparent Ki67 index was selected and up to 500 cells scored. The intraclass correlation coefficient (ICC) for the global method (0.87; 95%CI: 0.799-0.93) marginally met the prespecified success criterion (lower 95%CI ≥ 0.8) while the ICC for the hot-spot method (0.83; 95%CI: 0.74-0.90) did not. Visually, inter-observer concordance in location of selected hot-spots varies between cases. The median times for scoring were 9 and 6 minutes for global and hot-spot methods, respectively.

Conclusions: The global scoring method demonstrates adequate reproducibility to warrant next steps toward evaluation for technical and clinical validity in appropriate cohorts of cases. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between laboratories further. This article is protected by copyright. All rights reserved

Kim JY, Lee DW et Al. – Prognostic role of body mass index is different according to menopausal status and tumor subtype in breast cancer patientsBreast Cancer Res Treat. 2019 Apr 26. doi: 10.1007/s10549

Background: Although controversial, obesity and underweight may have a negative impact on breast cancer outcome. However, the relationship between body mass index (BMI) and breast cancer outcomes according to tumor subtype and menopausal status remains unclear.

Methods: This study investigated the association between BMI and breast cancer outcome in stage I-III breast cancer patients. The relationships were further evaluated according to tumor subtype and menopausal status.

Results: A total of 5919 patients, 3475 (58.7%) hormone receptor (HR)(+) human epidermal growth factor receptor 2 (HER2)(-), 608 (10.3%) HR(+)HER2(+), 621 (10.5%) HR(-)HER2(+), and 1079 (18.2%) HR(-)HER2(-) were included. Underweight and obesity had a negative impact on relapse-free survival but did not affect overall survival. Importantly, the prognostic role of BMI was different according to tumor subtype and menopausal status. In HR(+)HER2(-) patients, underweight was associated with poor relapse-free survival and overall survival in pre-menopausal women. In contrast, obesity had negative impact on relapse-free survival and overall survival in HR(+)HER2(-) post-menopausal patients. Underweight may have a negative prognostic role in HR(+)HER2(+) patients. However, BMI did not impact the outcome of HR(-)HER2(+) and HR(-)HER2(-) patients.

Conclusions: The impact of BMI on breast cancer outcome was dependent on tumor subtype and menopausal status. In HR(+)HER2(-) patients, underweight and obesity had a negative prognostic role in pre-menopausal and post-menopausal women, respectively. These findings in Asian population should be further evaluated and compared in Western population.

Lu L et Al. – BRCA1 mRNA expression modifies the effect of T cell activation score on patient survival in breast cancer. – BMC Cancer. 2019 Apr 25;19(1):387. doi: 10.1186/s12885

Background: Effector CD8+ T cell activation and its cytotoxic function to eradicate tumor cells depend on the T cell recognition of tumor neoantigens, and are positively associated with improved survival in breast cancer. Tumor suppressor BRCA1 and cell cycle regulator CCND1 play a critical role in maintaining genome integrity and tumorigenesis, respectively. However, it is still unclear how BRCA1 and CCND1 expression levels affect the effect of T cell activation on breast cancer patient survival.

Methods: The interactions between T cell activation status and either BRCA1 or CCND1 expression were evaluated using Kaplan-Meier survival curves and multivariate Cox regression models in a public dataset with 1088 breast cancer patients.

Results: Among the patients with low BRCA1 or CCND1 expression, the Activation group showed better overall survival than the Exhaustion group. Adjusted hazards ratios were 0.43 (95% CI: 0.20-0.93) in patients with a low BRCA1 level, and 0.39 (95% CI: 0.19-0.81) in patients with a low CCND1 level, respectively. There was a significant trend in both subgroups (p-trend = 0.011 in the low BRCA1 group, and p-trend = 0.009 in the low CCND1 group). In contrast, there is no significant association in patients with either high BRCA1 or high CCND1 levels. There is a significant interaction between T cell activation status and BRCA1 level (p = 0.009), but not between T cell activation status and CCND1 level (p = 0.135).

Conclusions: BRCA1 expression modified the effect of T cell activation status on patient survival in breast cancer, suggesting that the existence of neoantigens and the enhancement of neoantigen presentation in combination with immune checkpoint blockade may have synergistic effects on patient outcome

Pan B, Xu Y et AL. – The prognostic comparison among unilateral, bilateral, synchronous bilateral, and metachronous bilateral breast cancer: A meta-analysis of studies from recent decade (2008-2018). – Cancer Med. 2019 Apr 30. doi: 10.1002/cam4.2198.

Background: The incidence of bilateral breast cancer (BBC) is increasing nowadays comprising 2%-11% of all breast cancer (BC). According to the interval time between the first and second cancer, BBC could be divided into synchronous (SBBC) and metachronous (MBBC). However, this interval time is quite different across studies. It remains controversial whether the survival of BBC, SBBC, and MBBC is similar or worse compared to that of unilateral breast cancer (UBC), and whether the survival of SBBC is similar or worse compared to MBBC. To better understand the survival of UBC, BBC, SBBC, and MBBC and how the interval time would influence the prognosis of SBBC and MBBC, we performed this meta-analysis on studies from recent 10 years (2008-2018).

Methods: Databases of PubMed, Embase, and Web of Science were searched for relevant studies within recent 10 years. Hazard ratio (HR) was adopted to evaluate the difference of overall survival (OS) of UBC, BBC, SBBC, and MBBC. HR of OS comparisons were performed between BBC vs UBC, SBBC vs UBC, MBBC vs UBC, and SBBC vs MBBC with 3, 6, 12 months as the interval time, respectively.

Results: There were 15 studies of 72 302 UBC and 2912 BBC included in the meta-analysis. The summary HR of OS comparison between BBC vs UBC was 1.68 (95% CI: 1.28-2.20), SBBC vs UBC was 2.01 (95% CI: 1.14-3.55), MBBC vs UBC was 3.22 (95% CI: 0.75-13.78). When 3, 6, 12 months were used as the interval time, the summary HR of the OS comparison between of SBBC vs MBBC were 0.64 (95% CI: 0.44-0.94), 1.17 (95% CI: 0.84-1.63) and 1.45 (95% CI: 1.10-1.92), respectively.

Conclusions: BBC and SBBC showed worse prognosis in terms of OS compared to UBC while MBBC manifested similar or non-superior survival as UBC. The OS comparison between SBBC and MBBC changed with different interval time used. The longer the interval time used, the worse the survival of SBBC. SBBC with interval of 3-12 months between the two cancers had the worst prognosis. When 6 months was used to differentiate SBBC from MBBC, these two clinical entities showed similar OS.

Ji F, Xiao WK, Yang CQ – Tumor location of the central and nipple portion is associated with impaired survival for women with breast cancer. – Cancer Manag Res. 2019 Apr 9;11:2915-2925. doi: 10.2147/CMAR.S186205. eCollection 2019.

Background: Tumor location in the breast varies, with the highest frequency in the upper outer quadrant and lowest frequency in the lower inner quadrant. Nevertheless, tumors in the central and nipple portion (TCNP) are poorly studied types of breast cancer; therefore, we aimed to clarify the clinicopathological characteristics and prognostic features of TCNP.

Methods: Using the Surveillance, Epidemiology, and End Results database, we identifed 105,037 patients diagnosed with tumor in the breast peripheral quadrant (TBPQ) (n=97,046) or TCNP (n=7,991). The chi-squared test was used to compare categorical variables across TCNP and TBPQ. Cox proportional hazard models with hazard ratios were applied to estimate the factors associated with prognosis.

Results: The median follow-up was over 43 months. Compared with TBPQ, TCNP patients were signifcantly older (age ≥66 years: 40.4% vs 34.1%, P<0.001), with larger tumor sizes (>20 mm size: 46.9% vs 37.3%, P<0.001), higher proportions of TNM stage II-III (18.6% vs 9.9%, P<0.001), and more mastectomies (58.1% vs 37.8%, P<0.001). The breast cancer-specifc survival (BCSS)/overall survival (OS) rate was signifcantly worse for TCNP than for TBPQ. Multivariate Cox analysis showed a higher hazard ratios for TCNP over TBPQ (BCSS: hazard ratios =1.160, P=0.005, 95% CI: 1.046-1.287; OS: hazard ratios =1.301, P<0.001, 95% CI: 1.211-1.398). A subgroup analysis revealed inferior outcomes for TCNP in TNM stage II-III and breast subtype subgroup. Multivariate logistic regression indicated that TCNP was an independent contributing factor to LN metastasis.

Conclusions: TCNP was associated with older age, larger tumor size, higher TNM stage, and lymph node metastasis. Compared with TBPQ, TCNP had adverse impacts on BCSS and OS