How does disease control rate differ from overall response rate?

Disease Control Rate vs. Overall Response Rate

Disease Control Rate (DCR) includes complete response, partial response, AND stable disease, while Overall Response Rate (ORR) only counts complete and partial responses—making DCR a broader measure that captures all patients whose disease is not progressing. 1

Key Definitional Differences

Overall Response Rate (ORR):

• Includes only Complete Response (CR) + Partial Response (PR) 1
• CR = disappearance of all target lesions 1
• PR = at least 30% decrease in sum of target lesion diameters 1

Disease Control Rate (DCR):

• Includes CR + PR + Stable Disease (SD) 1
• SD = neither sufficient shrinkage to qualify as PR nor sufficient increase to qualify as progressive disease 1
• Captures a broader population of patients benefiting from treatment 2

Clinical Significance and Practical Implications

DCR consistently shows higher percentages than ORR in clinical trials because it includes the stable disease population. For example, in the BEACON CRC trial, the ORR was 48% while the DCR was 100% 2. Similarly, in PRRT-treated neuroendocrine tumors, DCR ranged from 80-90% while ORR was only 25% 2.

The stable disease component matters clinically. In advanced colorectal cancer, patients with stable disease who achieved clinical benefit had survival outcomes comparable to responders, significantly better than those with progressive disease 3. In atezolizumab-treated urothelial cancer, patients with stable disease had median overall survival exceeding 1 year 4.

Critical Limitations as an Endpoint

DCR is explicitly "neither a defined nor validated primary endpoint" and should only be reported as a secondary endpoint in clinical trials 1. The major limitations include:

• Lack of standardization: Duration of stable disease required varies across trials 1
• Limited correlation with survival: DCR shows only moderate correlation (r=0.470) with overall survival hazard ratios 1
• Potential for exaggeration: DCR may overstate anticancer activity, particularly when duration of stable disease is not specified 5

When DCR Provides Value

Use DCR as supplementary information in these specific contexts:

• Phase II single-arm studies as a descriptive measure 1
• When reported alongside validated endpoints like progression-free survival and overall survival 1
• In platinum-resistant ovarian cancer, where DCR correlated better with OS (r=0.748) than ORR alone (r=0.564) 6
• In extensive-stage small cell lung cancer, where DCR at 8 weeks predicted subsequent survival (HR 0.50, p<0.0001) 7

Clinical Decision-Making Algorithm

When evaluating treatment efficacy:

1. Prioritize overall survival and progression-free survival over both DCR and ORR 1
2. If only response data available: Recognize that ORR underestimates clinical benefit by excluding stable disease patients who may have meaningful outcomes 6, 3
3. If DCR is reported: Verify the duration of stable disease required—without this specification, DCR provides ambiguous information 1, 5
4. In slow-growing tumors (neuroendocrine tumors, certain renal cell carcinomas): DCR may be more clinically relevant than ORR alone 2

Common pitfall: Treating DCR as evidence of drug efficacy equivalent to objective response—stable disease without duration criteria or symptom improvement may simply reflect slow tumor biology rather than treatment effect 5, 3.