Comparison of point a based plans with clinical target volume-based three-dimensional plans using dose–volume parameters in small lesion of cervical cancer brachyterapy


Ozer E. E., Bagci M., KOÇAK UZEL E., Soydemir G. P., Figen M., Bolukbas M. K.

European Journal of Gynaecological Oncology, cilt.42, sa.5, ss.936-942, 2021 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 42 Sayı: 5
  • Basım Tarihi: 2021
  • Doi Numarası: 10.31083/j.ejgo4205141
  • Dergi Adı: European Journal of Gynaecological Oncology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE
  • Sayfa Sayıları: ss.936-942
  • Anahtar Kelimeler: Intracavitary brachytherapy, Cervical cancer, Point A, HR-CTV, Tumor size, Three-dimensional treatment plan, CT scan
  • Sağlık Bilimleri Üniversitesi Adresli: Evet

Özet

Objective: Intracavitary brachytherapy (ICBT) is the most critical part of cervical cancer treatment which contains a combination of external and intracavitary radiotherapy. We aimed to compare two different plans normalized to point A and the high-risk clinical target volume (HR-CTV) in terms of the target volume and doses for organs at risk (OARs). Methods: Twenty-eight patients with small-residue cervical tumor volume who received CT-based brachytherapy treatment with uterus tandem and double ovoid applicators were included in the study. 3D-ICBT treatment plans normalized to HR-CTV and point A were applied separately to five fractions. We made a total of 280 plans for the two treatment techniques. The patients were given a dose of 5.5 Gy per fraction for a total of 27.5 Gy in 5 fractions. The doses to OAR (rectum, sigmoid, and bladder) and HR-CTV were compared between HR-CTV and point A - based plans. Results: In the brachytherapy treatment planning, the mean doses of HR-CTV D90 and IR-CTV D100 were significantly lower in each fraction and in the total doses when normalized to HR-CTV than when normalized to point A (p < 0.001). D1cc, D2cc, and Dmax values of OAR doses obtained from the brachytherapy treatment planning were significantly lower in each fraction and in the total doses when normalized to HR-CTV than when normalized to point A (p < 0.001). Conclusion: Our findings revealed that, particularly in small-volume HR-CTV after EBRT, plans normalized to HR-CTV can reduce overdose in the target tissue and avoid unnecessary OAR irradiation compared to the plans normalized to point A.