What dose/fractionation would you recommend?
I too have been faced with this dilemma as we attempt to lessen patient, staff exposure and consolidate and minimize resources such as our anesthesia and equipment we typically use for these procedures. While my experience has always been with 5 fractions, I am grateful for attending the ASTRO plenary some 3 yrs ago when the IAEA trial results were discussed. 2 vs 4 fractions, outcomes were measured and inferior in the 2 fractions. Toxicities were presented and appear tolerable. Therefore, I have also converted to 4 fractions in patients that I feel the OARs can achieve the set limits. There is also a Red Journal paper from the 90’s, my very capable resident, Rebecca Shulman found, which reviews toxicities and suggests a cutoff of 7.5gy or less per fx to limit the toxicities.
First author Orton, red journal 1991. Wayne state university: the paper has data both LDR & HDR data for 17,000 patients and discusses many points; however, I think most applicable to our situation is Table 10. Bear in mind however, that the mean fractionation on this review was 5 (although many cases of 4 fractions do exist and that patients were being planned to point A at this time).
Related Questions
We have been using 7gy x 4 instead of 5 fraction regimen in the past. A 2 fraction regimen showed lower local control in comparison to 4 fractions in the IAEA randomized trial.
Or use 8 Gy x 3 and spinal (not gen) anesthesia.
We have been using 8Gyx3, twice a week for many years. Previously our retrospective study showed no major difference between 6Gyx5 vs. 8Gyx3.
I trained with the "inventor" of 8 Gy x 3: if one searches Red J for Dr. T. N. Roman, one will see it.
Dr. Roman was a Ob-Gyn that left Ob-Gyn and went into rad onc (he is now R.I.P.); it was a privilege to train with him because being an Ob-Gyn + rad onc, he knew what he was talking about. I did so many T&O with him that was unbelievable.
Between 1984-1989, he did 187 cases of T&O using HDR, the first group in N. America using HDR for cervix ca. At ASTRO presentation in 1990s, he was criticized by many in the audience for using HDR because LDR was the standard of care! Some in the audience even said "High-Dose Rate" is "High-Risk"...
Dr Roman initially used 10 Gy x 3 but settled down at 8 Gy x 3.
All done under spinal anesthesia.
This is the seminal paper from 1993, 27 years ago:
https://www.redjournal.org/article/0360-3016(93)90452-2/fulltext
For a T&R patient who has gotten 7 Gy x 2 and is now COVID +, would you consider 1 high dose fraction of 9-10 Gy to minimize exposure to staff?
Two options:
outpatient 7 Gy in two separate fractions;
if not feasible, then we would consider one fraction of 9 Gy or so making sure d 90 is 85 Gy and OAR dose constraints are met.
It's important EQ2 dose to HRCTV is around 85 Gy and OAR doses are respected (2cc rectum 65 Gy, sigmoid 70 Gy and bladder 80 Gy or below).