Oncology Response Assessment Tool
RECIST 1.1 & PCWG3 Criteria Calculator
For Clinical Trial & Research Use
v2.1
Quick Reference
RECIST 1.1
Soft Tissue
PCWG3
Bone Lesions
Target Lesions
Max 5 total, 2 per organ
Bone Rule
2+2 Confirmation
Criteria Comparison
| Aspect | RECIST 1.1 | PCWG3 |
|---|---|---|
| Primary Use | Solid tumors (soft tissue) | Prostate cancer bone mets |
| Measurement | Lesion size (mm) | Lesion count |
| Target Lesions | Yes, max 5 | No |
| Response Categories | CR, PR, SD, PD | PD or Non-PD only |
| New Lesions = PD | Any single lesion | ≥2 confirmed lesions |
| Bone Flare | Not considered | Considered (2+2 rule) |
| Imaging Frequency | 6-8 weeks | Baseline, 8w, then 16w |
RECIST 1.1 Criteria
| Response | Target Lesions | Non-target Lesions | New Lesions |
|---|---|---|---|
| Complete Response (CR) | All disappeared | All disappeared | None |
| Partial Response (PR) | ≥30% ↓ from baseline | Non-PD or CR | None |
| Stable Disease (SD) | Neither PR nor PD | Non-PD or CR | None |
| Progressive Disease (PD) | ≥20% ↑ from nadir + ≥5mm ↑ | Unequivocal progression | Any new soft tissue |
Measurement Rules:
- Non-nodal lesions: Longest diameter ≥10mm (CT/MRI)
- Nodal lesions: Short axis ≥15mm (measurable), 10-14mm (non-target)
- Baseline: Sum of diameters (SoD) of all target lesions
- Nadir: Smallest SoD recorded since baseline
PCWG3 Bone Progression Rules
| Scenario | Week 8 Scan | Follow-up Scan | Interpretation |
|---|---|---|---|
| Confirmed PD | ≥2 new lesions | ≥2 additional new lesions | PD (confirmed) |
| Unconfirmed PD | ≥2 new lesions | <2 new lesions | PDu (needs confirmation) |
| Delayed PD | ≤1 new lesion | ≥2 new lesions (confirmed) | PD (backdate to first detection) |
| Non-PD | <2 new lesions | <2 new lesions | Non-PD (continue monitoring) |
Imaging Schedule:
- Baseline: Full bone scan + CT/MRI
- Week 8-9: First follow-up (flare detection)
- Post-week 8: Confirmation scan (if PDu)
- Subsequent: Every 16-17 weeks
Assessment Workflow
1
Check New Lesions
Soft tissue: Any new = PD
Bone: ≥2 new → PDu (needs confirmation)
2
Assess Target Lesions
Calculate Sum of Diameters (SoD)
Compare to baseline and nadir
3
Assess Non-target Lesions
Qualitative assessment
Includes bone disease (PCWG3)
4
Determine Overall Response
Combine all components
PD overrides all other responses
RECIST 1.1 Calculator
Calculate soft tissue/visceral lesion response
Sum of diameters at baseline
Sum of diameters at current visit
Smallest SoD recorded since baseline
Calculation Rules:
PR:
Current ≤ Baseline × (1 - 0.30)
PD:
Current ≥ Nadir × (1 + 0.20) AND ↑ ≥5mm
PCWG3 Bone Progression Calculator
Assess bone lesion progression using "2+2" rule
New bone lesions detected at week 8 scan
Additional new lesions at follow-up scan
Confirmation Status:
PCWG3 "2+2" Rule:
2
new lesions at Week 8
+
2
additional new lesions at follow-up
=
PD
Overall Response Calculator
Combine RECIST and PCWG3 for final assessment
RECIST Components:
New Lesions:
PCWG3 Bone Status:
Response Hierarchy:
1
Check for PD (overrides all)
2
Check CR conditions
3
Check PR conditions
4
Check SD conditions
Lesion Measurability Check
Determine if lesion meets RECIST 1.1 measurability criteria
Measurability Criteria:
Non-nodal Lesions:
- ≥10mm: Measurable (Target candidate)
- <10mm: Non-target
Nodal Lesions (short axis):
- ≥15mm: Measurable (Target)
- 10-14mm: Pathologic, non-target
- <10mm: Normal, exclude