Tensor Regression-based Model to Investigate Heterogeneous Spatial Radiosensitivity After I-125 Seed Implantation for Prostate Cancer

In Vivo. 2021 Jan-Feb;35(1):489-497. doi: 10.21873/invivo.12283.

Abstract

Background/aim: We established a data-driven method for extracting spatial patterns of dose distribution associated with radiation injuries, based on patients with prostate cancer who underwent iodine-125 (I-125) seed implantation.

Patients and methods: Seventy-five patients underwent I-125 seed implantation for prostate cancer. We modeled the severity of lower urinary tract symptoms (LUTS) to be estimated using a linear model, which is formulated as an inner product between the dose distribution D and voxel-wise radiosensitivity B inside the prostate. For the estimation, tensor regression based on a low-rank decomposition with generalized fused lasso penalty was applied.

Results: The spatial distribution of B was visually assessed. Positive parameters appeared dominantly in the region close to the urethra and the prostate base.

Conclusion: Our tensor regression-based model can predict intra-organ radiosensitivity in a data-driven manner, providing a compelling parameter distribution associated with the development of LUTS after I-125 seed implantation for prostate cancer.

Keywords: Prostate cancer; anatomical standardization; brachytherapy; heterogeneous intra-organ radiosensitivity; tensor regression.

MeSH terms

  • Brachytherapy*
  • Humans
  • Iodine Radioisotopes
  • Male
  • Prostatic Neoplasms* / radiotherapy
  • Radiation Tolerance
  • Radiotherapy Dosage

Substances

  • Iodine Radioisotopes
  • Iodine-125