- Turkish Journal of Medical Sciences
- Vol: 45 Issue: 1
- Is there any impact of PET/CT on radiotherapy planning in rectal cancer patients undergoing preopera...
Is there any impact of PET/CT on radiotherapy planning in rectal cancer patients undergoing preoperative IMRT?
Authors : Diclehan Kiliç, Serap Çatli, Şükran Ülger, Lütfiye Özlem Kapucu
Pages : 129-135
Doi:10.3906/sag-1312-149
View : 17 | Download : 6
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :To investigate the effect of positron emission tomography-computed tomography (PET/CT)-based contouring on dosimetric parameters in rectal cancer patients undergoing preoperative intensity-modulated radiation therapy (IMRT). Materials and methods: Preoperative radiation therapy plans with conformal radiotherapy (CRT) or IMRT were created and examined according to the CT- and PET/CT-based contouring of 20 rectal cancer patients, retrospectively. Results: The target volumes delineated with PET/CT were significantly larger than the volumes created by CT (P = 0.043). Dose delivered to 98% of the planning target volume was high in IMRT planning contouring with CT and PET/CT compared with CRT planning, but the difference was not statistically significant (P = 0.056). Percent volumes receiving 105% of dose and 110% of dose were low in IMRT planning when compared with CRT (P < 0.0001 and P = 0.044, respectively). The volumes receiving 45 Gy for the small intestine, femur heads, and bladder and the maximum dose received by the bladder were significantly lower in IMRT. Conclusion: We showed that the target volumes created with PET/CT are significantly larger than the target volumes created with CT and that IMRT provides lower radiation exposure to the tumor-free tissues compared to the CRT planning. The dosimetric results primarily favor IMRT planning in rectal cancer patients and consequently present the significant alteration in target volumes.Keywords : Intensity-modulated radiation therapy, PET/CT, rectal cancer, conformal radiotherapy, computed tomography