How to Calculate MSKCC Risk of Recurrence

The MSKCC Risk of Recurrence is a nomogram that predicts the probability of remaining free of renal cell carcinoma five years after surgery. It is based on a Cox proportional hazards model.

FORMULA

The model coefficients to calculate the 5-year risk of recurrence are as follows:

Variable	Coefficient
Intercept	-1.8397306
Symptoms
None	0
Incidental	0
Local	0.010522791
Systemic	0.85698406
Histology
None	0
Chromophobe	0
Conventional	1.0831942
Papillary	0.2448591
Tumor size	0.13834412
Pathologic stage
pT1	0
pT2	0.52675363
pT3a	0.19334187
pT3b/c	0.86140642

where \( x = \sum[\beta \times (\text{variable})] \)

Recurrence-Free Probability = 100% - Risk %

Enter the values for histology, symptoms, T stage, and tumor size, and calculate the result.

Note: Tumor size must be positive.

Using the MSKCC Risk of Recurrence Calculator

This calculator is useful for clinicians analyzing recurrence risk in renal cell carcinoma patients post-surgery.

Input histology, symptoms, T stage, tumor size. Outputs 5-year recurrence-free probability and risk of recurrence.

Example 1: Histology Conventional, Symptoms Incidental, T Stage T1, Tumor Size 3 cm.

1. Histology: Conventional
2. Symptoms: Incidental
3. T Stage: T1
4. Tumor Size: 3
5. Calculation: x ≈ -0.34124, exp(x) ≈ 0.711
6. Free Prob ≈ 93.869%
7. Risk ≈ 6.131%

Example 2: Histology Papillary, Symptoms Systemic, T Stage T3a, Tumor Size 5 cm.

1. Histology: Papillary
2. Symptoms: Systemic
3. T Stage: T3a
4. Tumor Size: 5
5. Calculation: x ≈ 0.14748, exp(x) ≈ 1.159
6. Free Prob ≈ 88.742%
7. Risk ≈ 11.258%

Use for quick clinical assessments.

Common FAQ

Below are frequently asked questions about MSKCC Risk of Recurrence:

• Q: What is the MSKCC Risk of Recurrence?
  A: A nomogram to predict 5-year recurrence-free probability after surgery for RCC.
• Q: What variables are used?
  A: Histology, symptoms, T stage, tumor size.
• Q: How accurate is this calculator?
  A: Based on validated model coefficients.
• Q: Can negative values be used?
  A: No, tumor size must be positive.

Advice on Interpreting Results

The recurrence-free probability is the chance of no recurrence at 5 years; risk is the chance of recurrence.

Higher free probability indicates better prognosis. Use with clinical judgment.