| Abstract [eng] |
The master’s final degree project focuses on using a reference delineation plan according to the recommendations of the European Society Radiation Oncology (ESTRO) in a left breast without lymph node cancer patient who has been diagnosed with a high grade of polymorphism “in situ” invasive ductal carcinoma. Breast cancer is the leading cause of cancer-related death in women (87.2 women per 100,000 population), although most patients are diagnosed with a malignancy that has not spread to other organs. Modern modelling of radiotherapy treatment is a complex procedure. Ultrasound, mammography, magnetic resonance imaging (MRI), and breast biopsy tests are used to diagnose cancer, surgical treatment, hormone therapy, chemotherapy, biological therapy, and radiation therapy are used for treatment, which can be used alone and achieve better survival results, also different treatments can be combined in between. During the implementation of the final project, patient delineation plans were developed by the head of the Radiotherapy department (Hospital of Lithuanian University of Health Sciences Kaunas Clinics) dr. Laimonas Jaruševičius and 15 other radiation-oncologists working in a department. These plans were evaluated with a reference delineation plan (developed according to ESTRO recommendations) using the treatment planning system “Eclipse” and the open-source software “EvaluateSegmentation”. The volumes of the clinical structures – CTV_WB, PTV_WB, and PTV_WB_dvh and the critical organs – Heart, Lung_ipsilat, and Spinal_cord were evaluated using the “Eclipse” system. DICE similarity coefficient was calculated in the “Eclipse” and “EvaluateSegmentation” software. Mathematical models were found using the “Origin 2021b”. The volumes of structures were analysed – CTV_WB (641.0 – 834.0 cm3), PTV_WB (934.4 – 1381.4 cm3), PTV_WB_dvh (761.4 – 908.3 cm3), Heart (399.7 – 636.5 cm3), Lung_ipsilat (1879.4 – 2057.3 cm3), and Spinal_cord (26.3 – 48.5 cm3). The ratio of PTV/CTV can explain the difference between the volumes of CTV_WB and PTV_WB; this ratio is 1.34 – 1.85 a. u. The values of the DICE coefficient were found to be the following: CTV_WB (0.88 – 0.96 a. u. (software) | 0.91 – 0.96 a. u. (“Eclipse”)), PTV_WB (0.86 – 0.96 a. u. (software) | 0.85 – 0.97 a. u. (“Eclipse”)). It has been observed that the open-source “EvaluateSegmentation” software gives very similar results to “Eclipse”. Therefore the “EvaluateSegmentation” software (differently than “Eclipse”) additionally can be calculated other coefficients, like Jaccard coefficient, area under the ROC curve, Cohen Kappa coefficient, Rand index, and adjusted Rand index. The value of covered the PTV_WB_dvh volume when the clinical goal – V24.70 ≥ 95% is 75.30 – 96.18%, the value of Heart is 6.35 – 18.31% (V1.50 <30%), the value of Lung_ipsilat is 14.39 – 15.75% (V8.00 <15%), the dose value of Spinal_cord was 1.38 – 1.77 Gy (Dmax <23.64 Gy). The dependence of the covered volume PTV_WB_dvh on the volume of the structure is 8-order polynomial (R2 = 0.6504), Heart is the inverse polynomial with centre (R2 = 0.9511), Lung_ipsilat has a linear dependence (R2 = 0.9994), and Spinal_cord is a Chesler-Cram maximal function (R2 = 0.9478). |
