Genomics and Applied Biology 2016, Vol.7, No.2, 1-7
1
Research Article Open Access
Influence of Radiotherapy on Frequency of Sister Chromatid Exchange,
Micronuclei and Binuclear Cells in Breast Cancer Patients
Turaçlar N.
1,
, KoçM.
2
, Yurdakul H.
3
, Tezcan Y.
2
, Vural H.
4
1 Vocational School of Health Services, Selcuk University, Konya, Turkey
2 Department of Radiation Oncology, Meram Medical Faculty of Necmettin Erbakan University, Konya, Turkey
3 Genetikon Lab, Konya, Turkey
4 Department of Medical Biology, Meram Medical Faculty of Necmettin Erbakan University, Konya, Turkey
Corresponding author email
Genomics and Applied Biology, 2016, Vol.7, No.2 doi
Received: 14 Jun., 2016
Accepted: 06 Sep., 2016
Published: 20 Oct., 2016
Copyright
© 2016 Turaçlar et al., This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Turaçlar N
.
, KoçM., Yurdakul H., Tezcan Y., and Vural H., 2016, Influence of Radiotherapy on Frequency of Sister Chromatid Exchange, Micronuclei and
Binuclear Cells in Breast Cancer Patients, Genomics and Applied Biology, 7(2): 1-7 (doi
Abstract
The aim of this study was to evaluate any cytogenetic change in sister chromatid exchange (SCE), micronuclei (MN) and
binuclear cell (BNC) of peripheral blood lymphocytes in breast cancer patients treated with postoperative radiation therapy (RT).
Frequency of the SCE, MN and BNC were examined in 22 breast cancer patients received RT and 10 healthy individuals. All
parameters were measured before (RT-a), at the completion of (RT-b) and three months after the completion of (RT-c) RT. A
significant difference emerged in SCE (p=0.008) and MN (p=0.004) between RT-a and control groups. There was not any statistically
significant difference in the SCE frequencies between RT-b and RT-c measurements.
The frequencies of MN were also significantly
higher in RT-b (p=0.005) and RT-c (p=0.005) than in control group. MN levels decreased to pre-RT levels three months after
completion of treatment.
Increasing MN and SCE frequencies following radiotherapy is an expected situation. Decrease in MN
frequency at 3-month after the completion of RT suggests that expected repair continues. Persistent SCE at the same period suggests
that recovery in SCE has not completed yet and a longer period of time is needed.
Keywords
MN; SCE; RT; Breast ca
Introduction
Breast cancer is the most prevalent malignant tumor among women across the world with the exception of skin
cancers and constitutes about 30% of all cancers seen in women (Aslan and Gürkan, 2007;
).
Breast cancer also comes second after lung cancer in women in terms of mortality rate. Radiotherapy (RT) has an
important place in invasive and non-invasive breast cancer therapy. In ductal carcinoma in situ (DCIS) treatment,
the goal is minimal recurrence risk, optimal cosmetic result and treatment of the breast by conserving it. In
prospective studies conducted, rates of > 10% local recurrence risk are reported in breast-conserving surgery
(BCS) even among low-risk patients in a five-year follow-up period. Invasive recurrence is observed in 31-64% of
the cases exhibiting local recurrence. Today, RT following breast conserving surgery is considered to be a standard
approach in DCIS treatment. On the other hand, in invasive breast cancer treatment, adjuvant RT is considered to
be a standard approach in early stage after BCS and after local mastectomy in advanced stage. It was shown in
phase III studies that compared only BCS and tamoxifen and BCS+RT+tamoxifen combination in cases having
positive prognostic factors and having positive hormone receptors that tamoxifen could not replace RT. RT after
BCS takes place in the form of whole breast 45-50 Gy followed by 10-15 Gy in tumor bed. In a European study
that investigated the effect of additional dose to tumor bed on local control, it was shown that treatment with
additional dosage made a contribution to local control in all age groups. There is a consensus on the need for
adjuvant RT if post-mastectomy 4 axillary lymph node (LN) metastasis is >5 cm tumor, and there is skin-facia
involvement. In recent years, as a consequence of the publication of the long-term results of Canadian and Danish
studies and their demonstration of local control and survival advantages through adjuvant RT, increasing rates of
adjuvant RT have been indicated in cases of with 1-3 LN metastasis (Yıldız, 2008).
