TURKISH JOURNAL OF ONCOLOGY 2022 , Vol 37 , Num 2
Early Effect of Radiotherapy on Serum Levels of HSP70 and S100B in Patients with Breast Cancer
Elif Eda ÖZER1,Nilgün IŞIKSAÇAN2,Gülşen Pınar SOYDEMİR1,Gülçin ŞAHİNGÖZ ERDAL3,Asuman GEDİKBAŞI4,Meltem KIRLI BÖLÜKBAŞ1
1Department of Radiation Oncology, University of Health Sciences, Bakırköy Dr. Sadi Konuk Training and Research Hospital, Istanbul-Turkey
2Department of Biochemistry, University of Health Sciences, Bakırköy Dr. Sadi Konuk Training and Research Hospital, Istanbul-Turkey
3Department of Medical Oncology, University of Health Sciences, Bakırköy Dr. Sadi Konuk Training and Research Hospital, Istanbul-Turkey
4Department of Biochemistry, Istanbul University Faculty of Medicine, Istanbul-Turkey
DOI : 10.5505/tjo.2022.3335 OBJECTIVE
This study aimed to evaluate the difference between serum levels of S100B and HSP70 in the non-metastatic, Luminal A breast cancer (BC) patients with the healthy population, and determine the impact of post-operative radiotherapy (RT) on serum markers.

METHODS
21 BC patients who underwent chest wall/breast±axillary RT after adjuvant chemotherapy and twentyone healthy individuals were included in the study group. The changes in serum HSP70 and S100B levels were observed in the study and control groups.

RESULTS
A total of 42 participants were included. A significant difference was found between the HSP70 and S100B measurements of the study and control groups before and after RT (P=0.001 and p<0.01, respectively). At the same time, the increase in HSP70 after RT was statistically significant (p=0.025 and p<0.05, respectively). However, the change in S100B measurements after RT was not statistically significant in the study group patients compared to before RT (p>0.627).

CONCLUSION
S100B and HSP70 levels are higher than the healthy population before and after RT in non-metastatic, luminal A BC patients. The significant increase in Hsp70 after RT may be due to the release from dying tumor cells in the microenvironment. Therefore, HSP70 levels in the blood may be useful for microscopic tumor focus detection or evaluation of treatment response. Keywords : Breast cancer; HSP70; radiotherapy; S100B