Image guidance guidance.

Pretty much everyone agrees that definitive radiation for prostate cancer deserves image guidance. Turns out, that’s a loose term. More than two decades after “image-guided radiotherapy” (aka IGRT for those of you following along in your billing code manual) came on the scene for prostate cancer, ESTRO final has consensus guidelines on when and how it should be used. There’s lots of fodder for a practical journal club here, but we’ll try to boil it down. Everyone can agree that images should be used to align the prostate, not skeleton. Ok but what that really means is that you shouldn’t be billing for IGRT without prostate fiducials or, at the very least, a kV-CT scan. How often, you ask? CT guidance should be performed daily even with the gentlest of fractionation. If not, planning margins on the prostate should be no less than 7 mm—compare that to no less than 4 mm with daily pre-treatment kV-CT and no less than 2 mm with fiducials. For this reason, fiducials are strongly encouraged for extreme hypofractionation. Patients may be frustrated to hear the realized advantages of full bladders remain unclear, but they'll walk away happy since routine bowel regimens are frowned upon. TBL: Check out the summary ESTRO guidelines on prostate IGRT for a sanity check. | Ghadjar, Radiother Oncol 2019