Common Response Definitions Used in Clinical Trials
| Response criterion | Brief definition | Expected effect on viable tumor cell mass |
|---|---|---|
| Pathologic complete response (ypT0) | No viable residual tumor tissue on thorough histopathologic analysis | 100% |
| Pathologic response | <10% viable tumor cells in residual tumor mass | <−90% |
| Objective response | >30% decrease in maximum diameter of tumor | <−65% |
| Stable disease | <30% decrease and <20% increase in maximum diameter of tumor | >−65% and <+20% |
| Biologic response | Inhibition of drug target as assessed by ex vivo analysis of tumor tissue | Undefined |