Half Beam Technique in Patient with Left Breast Cancer and Evaluate its Dosimetry Parameters from Dosevolume Histograms
Keywords:Radiotherapy, breast cancer, tolerance doses
Using of 3DCRT for the treatment of left breast cancer by a single isocenter with half beam in the junction
of tangential and supraclavicular fields is an important method. The purpose was to evaluate the outcome of
Radiation Treatment Plans (RTP) that includes planning target volume (PTV) dose, conformity index (CI),
homogeneity index (HI), organs at risk (OAR), and compared with tolerance doses of left-sided whole breast
irradiation by half beam technique. Thirteen patients with left breast cancer who had received radiotherapy
by using 6, 10, and 18 MV photons. The clinical target volume [CTV] was contoured as a target volume, and
left lung, right lung, heart, and spinal cord tissues as OAR planning technique was analyzed at Zhianawa
cancer center (ZCC), Sulaimany-KR-Iraq. There was No risk for 12 patients CI (<1), accept patient No.
(6) CI>1. the PTV was under coverage (4060±32.116 cGy), was close to 4005 Gy volume. The left lung,
and right lung mean dose was (33.923, 1018.231cGy < tolerance mean Dose (4000 cGy), and for Lt lung
Dose V20 < 30 cGy. Heart Dose V35 (2.354) <20Gy, and Heart mean Dose (cGy)Dose was (358.308 cGy)
< tolerance mean Dose (2600 cGy). Cord Max dose was (682.692cGy) < 2000. the Dose mean value of
esophagus was (29,077)cGy was <3400 (Esophagus Tolerance mean dose (cGy). The application of left
breast cancer provides significant advantages especially in PTV and OAR dosages.