Author: Adebayo Abe, Samuel Olaolu Adeneye, Bidemi I. Akinlade, Inioluwa Damilola Ariyo, Sylvester Entonu, Muhammad Habeebu, Adedayo O. Joseph, Oluwaseyi Oderinde, Oluwadara Ojediran, Margaret Dideolu Taiwo 👨🔬
Affiliation: University of Ibadan, University of Lagos, Missouri University of Science and Technology, Purdue University, NSIA-LUTH Cancer Center, University of Lagos, NSIA-LUTH Cancer Centre 🌍
Purpose:
Spatially Fractionated Radiation Therapy (SFRT) is an advanced radiotherapy technique designed to deliver highly heterogeneous radiation doses, aiming to optimize tumor control while minimizing toxicity to surrounding healthy tissues. This study evaluated the dosimetric planning performance of SFRT in prostate cancer (PCa) cases treated with intensity-modulated radiotherapy (IMRT).
Methods:
Ten PCa patients, with an average age of 68 years, were re-planned using Varian Eclipse treatment planning system. Hot and cold spots with a 2 mm diameter, spaced 3 mm apart, were delineated within the gross tumor volume (GTV) using the MAAS-SFRThelper platform. The treatment prescription of SFRT plans are 60 Gy/5 fractions, compared to the 60 Gy/20 fractions for IMRT plans. Key dosimetric parameters, including dose-volume histograms, maximum and mean doses to organs at risk (OARs), and target volume coverage, were analyzed.
Results:
Results demonstrated that SFRT significantly reduced the maximum doses to critical OARs compared to IMRT. The maximum bladder dose was reduced to 56.69 ± 2.49 Gy with SFRT versus 62.58 ± 1.11 Gy with IMRT (p <0.05), and rectal doses decreased from 62.51 ± 0.98 Gy to 53.89 ± 4.14 Gy (p <0.05). Doses to the left and right femoral heads were also significantly lower with SFRT (p <0.05). These improvements in OAR sparing did not compromise target volume coverage, with SFRT achieving comparable conformity indices to IMRT.
Conclusion:
This preliminary study demonstrated that SFRT plans can achieve reduced dose distributions to OARs in PCa patients. Further research will calculate the biological effective dose in comparison with IMRT plans to confirm that SFRT reduces radiotoxicity to OARs in PCa patients. This study underscores the potential of SFRT to enhance precision in radiotherapy, redefining treatment paradigms in PCa management.