progressive disease
Tumor response category indicating cancer growth or spread despite treatment.
Full Definition
Progressive disease (PD) is defined as at least a 20% increase in the sum of longest diameters of target lesions, taking as reference the smallest sum longest diameters recorded since treatment started, or the appearance of new lesions. This classification represents treatment failure and typically triggers consideration of alternative therapeutic approaches. Progressive disease can be further characterized as local progression (within the primary tumor bed), regional progression (involving nearby lymph nodes or structures), or distant progression (metastatic spread to new organs). The determination of progressive disease often marks a critical decision point in cancer management.
Usage
Usage note: Distinguish from pseudoprogression, particularly relevant in immunotherapy contexts.
In Context
- "Progressive disease was documented in 15% of patients at the first response assessment." — Clinical trial interim analysis
- "The patient developed progressive disease with new liver metastases after six cycles." — Treatment summary report