sbrt/srs +/- sensitizers/protectors

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anyone aware of ongoing research/trials using radiation sensitizers or protectors concurrently with the delivery of SBRT/SRS?

Since both SRS and SBRT give near ablative doses which not only destroy the target but the vasculature as well, there is not a particularly good scientific rationale for radiosensitizers. When your radiation doses alone are not sufficient for LC (locally advanced H&N cancer, cervical cancer, GI cancers) then you toss in chemo for increased cell kill.

Protectants are a bit more interesting. It seems only amifostine has panned out to administer during conventionally fractionated XRT. Since SRS and SBRT has strict size criteria however the chances of side effects (parenchymal necrosis, pneumonitis, RILD) are quite a bit lower.

Can't think of any with true chemo on board, but a few with targeted agents come to mind

BJU Int. 2011 Sep;108(5):673-8. doi: 10.1111/j.1464-410X.2010.09895.x. Epub 2010 Dec 13.
Simultaneous anti-angiogenic therapy and single-fraction radiosurgery in clinically relevant metastases from renal cell carcinoma.

Staehler M, Haseke N, Nuhn P, Tüllmann C, Karl A, Siebels M, Stief CG, Wowra B, Muacevic A.
Source

Department of Urology, University of Munich, Klinikum Grosshadern, Munich, Germany. michael.staehler@med.unimuenchen.de

A Phase II Trial of Stereotactic Body Radiation Therapy (SBRT) Combined with Erlotinib for Patients with Recurrent Non-small Cell Lung Cancer (NSCLC)

• B. Kavanagh
  • Affiliations
    
  • University of Colorado School of Medicine, Aurora, CO
  ,
• R. Abdulrahman
  • Affiliations
    
  • University of Texas Southwestern, Dallas, TX
  ,
• D.R. Camidge
  • Affiliations
    
  • University of Colorado School of Medicine, Aurora, CO
  ,
• D.E. Gerber
  • Affiliations
    
  • University of Texas Southwestern, Dallas, TX
  ,
• P.A. Bunn
  • Affiliations
    
  • University of Colorado School of Medicine, Aurora, CO
  ,
• J. Schiller
  • Affiliations
    
  • University of Texas Southwestern, Dallas, TX
  ,
• H. Choy
  • Affiliations
    
  • University of Texas Southwestern, Dallas, TX
  ,
• L. Gaspar
  • Affiliations
    
  • University of Colorado School of Medicine, Aurora, CO
  ,
• R. Doebele
  • Affiliations
    
  • University of Colorado School of Medicine, Aurora, CO
  ,
• R.D. Timmerman

When I was a resident, my institution ran an investigator-initiated trial looking at concurrent erlotinib with SRS from NSCLC brain mets. All study endpoints negative.

Originally Posted by Gfunk6

Since both SRS and SBRT give near ablative doses which not only destroy the target but the vasculature as well, there is not a particularly good scientific rationale for radiosensitizers. When your radiation doses alone are not sufficient for LC (locally advanced H&N cancer, cervical cancer, GI cancers) then you toss in chemo for increased cell kill.

Protectants are a bit more interesting. It seems only amifostine has panned out to administer during conventionally fractionated XRT. Since SRS and SBRT has strict size criteria however the chances of side effects (parenchymal necrosis, pneumonitis, RILD) are quite a bit lower.

does anybody still use amifostine? just curious

Originally Posted by Wallachia

does anybody still use amifostine? just curious

I've seen it used in some private practices. It's such a pain to use, especially with infusion-associated reactions that happen, especially the hypotension. I don't really see the point anymore, especially with IMRT for H&N.

Originally Posted by medgator

I've seen it used in some private practices. It's such a pain to use, especially with infusion-associated reactions that happen, especially the hypotension. I don't really see the point anymore, especially with IMRT for H&N.

Agreed. Haven't really seen a large need for it with IMRT.