ESTRO 2022 - Abstract Book

S1021

Abstract book

ESTRO 2022

The majority of patients survived after 6 years. The differences in Dmean thyroid did not influence in thyroid function. The increased Dmean contralateral breast, was not associated with radiation-induced second tumors on this location.

PO-1200 DIBH technique heart sparing In left breast Irradiation: benefits in comparison to FB technique

M. Caroprese 1 , C. Oliviero 1 , A. Barillaro 1 , A. Farella 1 , S. Clemente 1 , L. Goanta 1 , A. Russo 1 , L. Lo Conte 1 , R. Pacelli 1 , M. Conson 1

1 University “Federico II” School of Medicine, Department of Advanced Biomedical Sciences, Naples, Italy

Purpose or Objective Postoperative radiation therapy (RT) for left-sided breast cancer patients may be cause of heart toxicity. Deep inspiration breath hold (DIBH) technique reduces cardiac radiation exposure. The aim of this study Is to compare the dose distribution to cardiac substructures between DIBH and free breathing (FB) technique. Materials and Methods Cardiac substructures, cardiac chambers and coronary vessels, were delineated according to ESTRO guidelines on the simulation CT scans of ten left-sided breast cancer patients having undergone conserving surgery and breast RT. The plans were simulated in both, FB and DIBH CT scan in each patient to be equivalent for target coverage, namely 95% prescription dose (40 Gy In 15 fractions on whole breast plus 10 Gy In for fraction on tumor bed when appropriate) to 95% of target volume. Mean doses to the heart, cardiac substructures were retrieved and compared between DIBH and FB simulation plans. Results DIBH technique obtained a statistically significant decrease for all cardiac substructures evaluated, except for left circumflex artery. The average mean heart dose was reduced from 1.45 to 1.03 Gy (p 0.008). The mean dose to the LAD coronary artery was reduced from 5.56 to 2.89 Gy (p 0.009); the mean dose to the left ventricle was reduced from 2.13 to 1.42 Gy (p 0.016). Conclusion The dosimetric benefit of DIBH over FB therapy was consistently observed for all cardiac substructures. The DIBH technique promises a significant advantage in ameliorating the heart toxicity profile of left breast Irradiation. 1 Shaukat Khanum Memorial Cancer Hospital, Internal Medicine, LAHORE, Pakistan; 2 Shaukat Khanum memorial cancer hospital, Clinical and radiation oncology, LAHORE, Pakistan; 3 Shaukat Khanum memorial cancer hospital, Internal Medicine, LAHORE, Pakistan Purpose or Objective Breast cancer treatments bring adverse consequences that interfere with everyday functioning. Importantly, some of these treatments are associated with the reproductive health and child bearing potential. Tamoxifen is a selective estrogen receptor modulator and is a common endocrine therapy treatment for breast cancer. This study aims to find out the impact of tamoxifen on fertility in women who have been treated for breast cancer. Materials and Methods 331 female breast cancer survivors between ages 25 and 48 years, who were diagnosed between ages 20 and 42 and were at least 3 years post treatment ( average time 3 – 10 years post treatment) were interviewed telephonically, in the presence of a chaperone. The data was collected on a pre-selected questionnaire approved by the institutional review board and electronic entries of the interview were made in the patient’s medical record files. Results Women who were treated with tamoxifen after their diagnosis of breast cancer were less likely to conceive compared to women who did not receive tamoxifen. Out of the 331 patients, 21 were primarily infertile and another 20 had undergone either ovarian ablation or bilateral oophorectomy and hence, were excluded from the final analysis. Women who were treated with tamoxifen were substantially less likely to have a child post cancer diagnosis( CI 95%, P value 0.000). Out of the 163 patients on tamoxifen , 9.2 % were able to conceive as compared to 29.1% in the non tamoxifen arm. In order to further elucidate the link between tamoxifen and its late reproductive effects in cancer survivors, the patients were further cohorted based on their chemotherapy regimens , length of chemotherapy and adjuvant radiotherapy. Conclusion Our results suggest that breast cancer survivors who took tamoxifen were significantly less likely to have a child post treatment as compared to patients who did not receive tamoxifen. Similarly there was a significant delay in time to child bearing post treatment, in women who were receiving tamoxifen as compared to those who were not on tamoxifen. One of the most obvious reasons for this could be chalked upto the fact that patients on tamoxifen prophylaxis are advised against child bearing and conception keeping in view the fact that tamoxifen is a known teratogen. However, Many of the patients have reported not taking any extra precautions or contraceptive measures post their treatment. This was either PO-1201 Impact of tamoxifen on fertility and child bearing , in breast cancer survivors S. Khan 1 , S. Butt 2 , A. Faqah 3