Top Line: Is post-treatment PET prognostic of treatment outcomes for anal cancer?
The Study: FDG-PET is often used in the initial staging of anal cancer. However, it’s less clear how to use PET to assess treatment response. In fact, the NCCN guidelines don’t specifically recommend post-treatment PET. This prospective study sought to evaluate the prognostic value of post-treatment PET for anal cancer. The study enrolled 78 patients with anal cancer receiving definitive radiation (83% received concurrent chemotherapy). They had a pretreatment PET and then another PET 2 months after completing treatment in addition to standard clinical examination. At that 2 months scan, 47.4% had a complete metabolic response whereas 84.6% had a complete clinical response. Though metabolic response was significantly associated with disease-free and local recurrence-free survival, it was not as strong a predictor of outcome as clinical response. Of the 7 (9%) patients with what appeared to be progression on PET, 6 had a complete response on clinical exam.
TBL: In this prospective study, a PET/CT 2 months after treatment of rectal cancer was prognostic of treatment outcomes, however it did not perform as well as clinical exam and detected fewer complete responses. | Bailleux, Radiother Oncol 2023
The Study: FDG-PET is often used in the initial staging of anal cancer. However, it’s less clear how to use PET to assess treatment response. In fact, the NCCN guidelines don’t specifically recommend post-treatment PET. This prospective study sought to evaluate the prognostic value of post-treatment PET for anal cancer. The study enrolled 78 patients with anal cancer receiving definitive radiation (83% received concurrent chemotherapy). They had a pretreatment PET and then another PET 2 months after completing treatment in addition to standard clinical examination. At that 2 months scan, 47.4% had a complete metabolic response whereas 84.6% had a complete clinical response. Though metabolic response was significantly associated with disease-free and local recurrence-free survival, it was not as strong a predictor of outcome as clinical response. Of the 7 (9%) patients with what appeared to be progression on PET, 6 had a complete response on clinical exam.
TBL: In this prospective study, a PET/CT 2 months after treatment of rectal cancer was prognostic of treatment outcomes, however it did not perform as well as clinical exam and detected fewer complete responses. | Bailleux, Radiother Oncol 2023