48P - Different tumor biology in Russian and Dutch patients with breast cancer stage I

Date 08 May 2014
Event IMPAKT 2014
Session Welcome reception and Poster Walk
Topics Breast Cancer, Early Stage
Cancer Aetiology, Epidemiology, Prevention
Pathology/Molecular Biology
Presenter Irina Kolyadina
Citation Annals of Oncology (2014) 25 (suppl_1): i8-i16. 10.1093/annonc/mdu066
Authors I.V. Kolyadina1, P.J.K. Kuppen2, C.J.H. Van De Velde2, I.V. Poddubnaya3, N.G. Dekker-Ensink2, A. Sajet2, E. Bastiaannet2, B.E.M. Prinse2, C.C. Engels2, D.V. Komov1
  • 1Oncology Chair, Russian Medical Academy of Postgraduate Education; N.N. Blokhin Russian Cancer Research Center, 115409 - Moscow/RU
  • 2Surgery, LUMC, P.O. Box 9600 - Leiden/NL
  • 3Oncology Chair, Russian Medical Academy of Postgraduate Education, 115409 - Moscow/RU

Abstract

Material and methods:

In our analyses we included Russian (n = 315) and Dutch (n = 203) women with breast cancer stage I; Russian patients treated in RCRC, RMAPE (1985-2009), Dutch patients in LUMC (1985-1994). Primary treatment included radical surgery (mastectomy or breast-conserving surgery) ± adjuvant radiotherapy or systemic therapy. A Tissue Micro Array (TMA), with triplicate 1 mm tumor tissue punches taken from formalin-fixed paraffin-embedded tumor tissue of patients was constructed. Subsequently, sections were immunohistochemically stained for expression of ER, PR, HER2, Ki67, and immune markers (HLA-E, -G, and HLA-A, -B, -C (HC10-HCA2) and Foxp3). ER, PR, HLA-E and HLA-G were scored using the proportion of cells with nuclear (ER, PR) or membranous (HLA-E and G) staining, which was multiplied by the intensity of staining (0, 1, 2, or 3) to provide a score of 0–300. HC10, HCA2 and Ki-67 immunohistochemical stainings were scored using the percentage positive tumor. FoxP3 was scored by counting the number of positive cells. HER2 staining intensity was graded in accordance with the HercepTest protocol system. We used median expression for evaluation of expression results as positive (>median) or negative (< median) and compared histological data and immune marker expression in two independent geographic populations in statistic analyses made using SPSS 20,0.

Results:

The percentage of patients with ductal cancer was significantly lower in Russian compared to Dutch patients (66 vs 94%, p = 0,0001); but G1-tumors were more often diagnosed in Dutch (27%) than in Russian patients (7%, p = 0,0001). The percentage of ER-negative tumors was very similar in Russian and Dutch patients (34% vs 37%, p = 0,506) as well as the percentage of PR-negative tumors (49% vs 43%, p = 0,168). HER2-overexpression found some higher in Russian patients (11%) than Dutch (6%), p = 0,122. It was interesting that HLA-E expression was absent in 52% of the Dutch patients (median expression was 0) and in only 1% of the Russian patients (median expression was 180), p = 0,0001. In contrast, HLA-G expression present in 47% (Dutch) and in 26% (Russian) cases, p = 0,0001. Any other marker expression (HC10, HCA2 and Foxp3) was very similar in Russian and Dutch women.

Conclusion:

Russian and Dutch women with breast cancer stage I had different biology of tumors.

Disclosure:

All authors have declared no conflicts of interest.