File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Conference Paper: SU‐E‐T‐293: A Radiobiological Model Based Approach to Evaluate Brain Radiotherapy Fractionation Regimens

TitleSU‐E‐T‐293: A Radiobiological Model Based Approach to Evaluate Brain Radiotherapy Fractionation Regimens
Authors
Issue Date2013
Citation
Medical Physics, 2013, v. 40, n. 6, p. 271 How to Cite?
AbstractPurpose: To evaluate various brain radiotherapy fractionation regimens by calculating relative damaged volume (RDV) of normal brain while giving the same biologically effective dose (BED) to tumor. Methods: The RDV was computed for 5 brain cases with the tumor sizes varying between 0.9–63.2 cm3 for 17 different fractionation regimens (1–8, 10, 12, 15, 20, 25, 30, 35, 40, and 50 fractions). A 20Gy single fraction regimen was used as the tumor control probability reference. The LQ model with correction for tumor regrowth effect (Tpot) was used to determine BED to tumor. The RDV was calculated from patients brain DVHs and a logistic local response function, which is characterized by DL50, the dose required to produce 50% local damage. Various Tpot (5 –30 days) and DL50 (20 – 50Gy) values were used to calculate RDV for each patient. Assuming a homogeneous brain structure, we used RDV as a surrogate for brain normal tissue complication probability (NTCP). A smaller RDV value represents lower NTCP and higher therapeutic ratio. Results: The minimum RDV among 17 studied fractionation regimens varied with Tpot, DL50, and tumor size. Stereotactic radiosurgery (SRS) is the favorable treatment regimen for low DL50 (20Gy). For a small sized tumor (<5.8 cm3, in this study), SRS is preferred up to medium DL50 (35Gy) and low Tpot (5 days). The optimal number of fractions (a regimen with minimum RDV) increases up to 35 fractions with increasing DL50, Tpot, and tumor size. Greater than 10% RDV reductions were achieved in some situations compared to reference fractionation. Conclusion: This study demonstrates that the RDV with the same tumor BED could be used to evaluate different fractionation regimens. An optimal fractionation regimen, such as SRS vs. hypofractionation, may be determined by the DVH, DL50, and Tpot of a patient to improve the therapeutic ratio. © 2013, American Association of Physicists in Medicine. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/266801
ISSN
2023 Impact Factor: 3.2
2023 SCImago Journal Rankings: 1.052
ISI Accession Number ID

 

DC FieldValueLanguage
dc.contributor.authorXiao, N.-
dc.contributor.authorKong, F.-
dc.contributor.authorRyu, S.-
dc.contributor.authorChetty, I.-
dc.contributor.authorBurmeister, J.-
dc.contributor.authorJoiner, M.-
dc.contributor.authorJin, J.-
dc.date.accessioned2019-01-31T07:19:38Z-
dc.date.available2019-01-31T07:19:38Z-
dc.date.issued2013-
dc.identifier.citationMedical Physics, 2013, v. 40, n. 6, p. 271-
dc.identifier.issn0094-2405-
dc.identifier.urihttp://hdl.handle.net/10722/266801-
dc.description.abstractPurpose: To evaluate various brain radiotherapy fractionation regimens by calculating relative damaged volume (RDV) of normal brain while giving the same biologically effective dose (BED) to tumor. Methods: The RDV was computed for 5 brain cases with the tumor sizes varying between 0.9–63.2 cm3 for 17 different fractionation regimens (1–8, 10, 12, 15, 20, 25, 30, 35, 40, and 50 fractions). A 20Gy single fraction regimen was used as the tumor control probability reference. The LQ model with correction for tumor regrowth effect (Tpot) was used to determine BED to tumor. The RDV was calculated from patients brain DVHs and a logistic local response function, which is characterized by DL50, the dose required to produce 50% local damage. Various Tpot (5 –30 days) and DL50 (20 – 50Gy) values were used to calculate RDV for each patient. Assuming a homogeneous brain structure, we used RDV as a surrogate for brain normal tissue complication probability (NTCP). A smaller RDV value represents lower NTCP and higher therapeutic ratio. Results: The minimum RDV among 17 studied fractionation regimens varied with Tpot, DL50, and tumor size. Stereotactic radiosurgery (SRS) is the favorable treatment regimen for low DL50 (20Gy). For a small sized tumor (<5.8 cm3, in this study), SRS is preferred up to medium DL50 (35Gy) and low Tpot (5 days). The optimal number of fractions (a regimen with minimum RDV) increases up to 35 fractions with increasing DL50, Tpot, and tumor size. Greater than 10% RDV reductions were achieved in some situations compared to reference fractionation. Conclusion: This study demonstrates that the RDV with the same tumor BED could be used to evaluate different fractionation regimens. An optimal fractionation regimen, such as SRS vs. hypofractionation, may be determined by the DVH, DL50, and Tpot of a patient to improve the therapeutic ratio. © 2013, American Association of Physicists in Medicine. All rights reserved.-
dc.languageeng-
dc.relation.ispartofMedical Physics-
dc.titleSU‐E‐T‐293: A Radiobiological Model Based Approach to Evaluate Brain Radiotherapy Fractionation Regimens-
dc.typeConference_Paper-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1118/1.4814727-
dc.identifier.scopuseid_2-s2.0-85024793907-
dc.identifier.volume40-
dc.identifier.issue6-
dc.identifier.spage271-
dc.identifier.epage-
dc.identifier.isiWOS:000336849901577-
dc.identifier.issnl0094-2405-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats