Several grading systems are used to evaluate TRG, each with its criteria and classification:
1. Mandard System: Grades range from TRG 1 (complete response) to TRG 5 (no response). 2. Dworak System: Grades range from TRG 0 (no regression) to TRG 4 (complete regression). 3. AJCC System: This system is more complex and includes a combination of pathological and clinical factors to classify the tumor response.
