Webbläsaren som du använder stöds inte av denna webbplats. Alla versioner av Internet Explorer stöds inte längre, av oss eller Microsoft (läs mer här: * https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Var god och använd en modern webbläsare för att ta del av denna webbplats, som t.ex. nyaste versioner av Edge, Chrome, Firefox eller Safari osv.

Default user image.

Katarina Sjögreen Gleisner

Professor

Default user image.

Dosimetric quantities of neuroendocrine tumors over treatment cycles with 177Lu-DOTA-TATE

Författare

  • Daniel Roth
  • Johan Gustafsson
  • Carl Fredrik Warfvinge
  • Anna Sundlöv
  • Anna Åkesson
  • Jan Tennvall
  • Katarina Sjögreen Gleisner

Summary, in English

Tumor dosimetry was performed for 177Lu-DOTA-TATE with the aims of better understanding i) the range and variation of the tumor absorbed doses (ADs), ii) how different dosimetric quantities evolve over the treatment cycles, and iii) whether this evolution differs depending on the tumor grade. Such information is important for radiobiological interpretation and may inform the design of alternative administration schemes. Methods: Data come from 41 patients with neuroendocrine tumors (NETs) of grade 1 (n = 23) or 2 (n = 18), that had received between 2 and 9 treatment cycles. Dosimetry was performed for 182 individual lesions, giving in total 880 individual AD assessments across all cycles. Hybrid planar-SPECT/CT imaging was used, including quantitative SPECT reconstruction, voxel-based absorbed-dose-rate calculation, semi-automatic image segmentation, and partial-volume correction. Linear mixed-effect models were used to analyze changes over cycles in tumor ADs, absorbed-dose rates and activity concentrations at day-1, effective half-times, and tumor volumes. Tumors smaller than 8 ml were excluded from analyses. Results: Tumor ADs ranged between 2 and 77 Gy per cycle. On average the AD decreased over the cycles, with significantly different rates (P < 0.05) for grade 1 and 2 NETs of 6% and 14% per cycle, respectively. The absorbed-dose rates and activity concentrations at day-1 decreased by similar amounts. The effective half-times were less variable but shorter for grade 2 than grade 1 (P < 0.001). For grade 2 NETS the tumor volumes decreased, with a similar tendency in grade 1. Conclusion: The tumor AD, absorbed-dose rate and activity uptake decrease, in parallel with tumor volumes, between 177Lu-DOTA-TATE treatment cycles, particularly for grade 2 NETs. The effective half-times vary less but are lower for grade 2 than grade 1 NETs. These results may indicate the development of radiation-induced fibrosis and could have implications for the design of future treatment and dosimetry protocols.

Avdelning/ar

  • Forskningsgruppen för Systemisk strålterapi
  • Medicinsk strålningsfysik, Lund
  • Nuclear Medicine Physics
  • Medicinsk onkologi

Publiceringsår

2022-03

Språk

Engelska

Sidor

399-405

Publikation/Tidskrift/Serie

Journal of Nuclear Medicine

Volym

63

Issue

3

Dokumenttyp

Artikel i tidskrift

Förlag

Society of Nuclear Medicine

Ämne

  • Radiology, Nuclear Medicine and Medical Imaging
  • Cancer and Oncology
  • Other Physics Topics

Status

Published

Forskningsgrupp

  • Systemic Radiation Therapy Group
  • Nuclear Medicine Physics

ISBN/ISSN/Övrigt

  • ISSN: 0161-5505