SCIENCEBRING   /   HAMBURG, GERMANY
Login Register
International Journal of Advance Scientific Research SCIENTIFIC IDEAS. INTERNATIONAL PERSPECTIVES.
ISSN 2750-1396 12 issues per year · Monthly
Crossref DOI: 10.37547/ijasr
Submit Manuscript ↗

Search the Journal
Articles Published:

Assessment of Physiological and Cellular Dose Thresholds Relative to Delivery Protocols in Focused External Beam Treatment

Vol. 6 No. 04 (2026): Volume 06 Issue 04 Pages 1-14
Authors
  • Dr. Andi Pratama
    Department of Scientific Research, Universitas Indonesia, Depok, Indonesia
  • Dr. Siti Rahmawati
    Faculty of Applied Sciences, Bandung Institute of Technology, Bandung, Indonesia
RESEARCH OVERVIEW

Abstract

The optimization of dose delivery in focused external beam radiotherapy remains a critical challenge due to the complex interplay between physical dose distribution and biological response at both physiological and cellular levels. This study presents a comprehensive analytical framework for assessing dose thresholds in relation to varying delivery protocols, particularly in stereotactic and intensity-modulated radiotherapy techniques. The research integrates radiobiological modeling, dosimetric evaluation, and clinical protocol comparisons to elucidate how treatment parameters influence tissue response, tumor control probability (TCP), and normal tissue complication probability (NTCP).

Drawing on established theoretical constructs such as the linear-quadratic (LQ) model and dose–volume histogram (DVH) analysis, the study examines the variability in dose thresholds across different fractionation schemes, including hypofractionated and high-dose stereotactic body radiotherapy (SBRT). Empirical evidence from clinical trials and retrospective analyses demonstrates that dose heterogeneity, organ motion, and treatment margins significantly affect biological outcomes. Furthermore, the investigation highlights the importance of advanced delivery techniques such as volumetric modulated arc therapy (VMAT) and image-guided radiotherapy (IGRT) in achieving precise dose localization while minimizing exposure to organs at risk (OARs).

A critical evaluation of protocol-dependent variations reveals that conventional uniform dose prescriptions may not adequately capture the complexity of cellular damage mechanisms, particularly under high-dose-per-fraction conditions. The study proposes a multi-scale assessment framework that integrates physiological tolerance thresholds with cellular radiosensitivity metrics, enabling more accurate prediction of therapeutic outcomes.

The findings underscore the necessity of personalized dose optimization strategies that account for inter-patient variability, tumor characteristics, and dynamic anatomical changes. Limitations related to model assumptions and data generalizability are also discussed. Ultimately, this research contributes to the advancement of precision radiotherapy by offering a robust analytical foundation for aligning dose delivery protocols with biological effectiveness.

Keywords

  • Radiotherapy dosimetry
  • Biological dose threshold
  • External beam therapy
SOURCES & CITATIONS

References

1. Bentzen SM, Dörr W, Gahbauer R et al. Bioeffect modeling and equieffective dose concepts in radiation oncology – terminology, quantities and units. Radiother Oncol 2012;105:266–8.
2. Beyzadeoglu M, Ozyigit G, Ebruli C. Basic Radiation Oncology. Berlin Heidelberg: Springer-Verlag, 2010, 145–73.
3. Blomgren H, Lax I, Naslund I et al. Stereotactic high dose fraction radiation therapy of extracranial tumors using an accelerator. Clinical experience of the first thirty-one patients. Acta Oncol 1995;34:861–70.
4. Chan O, Lee M, Hung A et al. The superiority of hybrid-volumetric arc therapy (VMAT) technique over double arcs VMAT and 3D-conformal technique in the treatment of locally advanced non-small cell lung cancer – a planning study. Radiother Oncol 2011;101:298–302.
5. Douglas J. ICRU. 50 Prescribing, recording, and reporting photon beam therapy. In: International Commission on Radiation Units and Measurements ICRU Report 50. Bethesda, MD, 1993.
6. Fowler JF. The linear-quadratic formula and progress in fractionated radiotherapy. Br J Radiol 1989;62:679–94.
7. Kawahara D, Saito A, Ozawa S et al. Assessment of biological dosimetric margin for stereotactic body radiation therapy. J Appl Clin Med Phys 2020;21:31–41.
8. Kartutik K, Wibowo WE, Pawiro SA et al. Comparison of radiotherapy dosimetry for 3D-CRT, IMRT, and SBRT based on electron density calibration. J Phys 2016;694(1):012017.
9. Nagata Y, Takayama K, Matsuo Y et al. Clinical outcomes of a phase I/II study of 48 Gy of stereotactic body radiotherapy in 4 fractions for primary lung cancer using a stereotactic body frame. Int J Radiat Oncol Biol Phys 2005;63:1427–31.
10. Onimaru R, Shirato H, Shimizu S et al. Tolerance of organs at risk in small-volume, hypofractionated, image-guided radiotherapy for primary and metastatic lung cancers. Int J Radiat Oncol Biol Phys 2003;56:126–35.
11. Shien G, Jie Y, Jiang W et al. Stereotactic body radiation therapy for centrally-located lung tumors. Oncol Lett 2014;7:1292–6.
12. Shirato H, Seppenwoolde Y, Kitamura K et al. Intrafractional tumor motion: lung and liver. Semin Radiat Oncol 2004;14:10–8.
13. Taremi M, Hope A, Dahele M et al. Stereotactic body radiotherapy for medically inoperable lung cancer: prospective, single-center study of 108 consecutive patients. Int J Radiat Oncol Biol Phys 2012;82:967–73.
14. Timmerman R, Papiez L, McGarry R et al. Extra cranial stereotactic radioablation: results of a phase I study in medically inoperable stage I non-small cell lung cancer. Chest 2003;124:1946–55.
15. Timmerman RD, Michalski J, Fowler J et al. A Phase II Trial of Stereotactic Body Radiation Therapy (SBRT) in the Treatment of Patients with Medically Inoperable Stage I/II Non-small Cell Lung Cancer, Protocol 0236. Philadelphia: RTOG, 2006.
16. Uematsu M, Shioda A, Suda A et al. Computed tomography-guided frameless stereotactic radiotherapy for stage I non-small cell lung cancer: a 5-year experience. Int J Radiat Oncol Biol Phys 2001;51:666–70.
17. van Herk M, Remeijer P, Rasch C, Lebesque JV. The probability of correct target dosage: Dosepopulation histograms for deriving treatment margins in radiotherapy. Int J Radiat Oncol Biol Phys 2000;47:1121–35.
18. Waghorn BJ, Shah AP, Rineer JM et al. A margin-based analysis of the dosimetric impact of motion on step-and-shoot IMRT lung plans. Radiat Oncol 2014;9:46.
19. Wilke L, Andratschke N, Blanck O et al. ICRU report 91 on prescribing, recording, and reporting of stereotactic treatments with small photon beams: statement from the DEGRO/DGMP working group stereotactic radiotherapy and radiosurgery. Strahlenther Onkol 2019;195:193–8.
20. Wulf J, Haedinger U, Oppitz U et al. Stereotactic radiotherapy for primary lung cancer and pulmonary metastases: a noninvasive treatment approach in medically inoperable patients. Int J Radiat Oncol Biol Phys 2004;60:186–96.
DISCOVER RELATED RESEARCH

Similar Articles

Continue exploring the collection ↗
1-10 of 55