Solitary Pulmonary Nodule Malignancy Risk (Mayo Clinic model)

Smoker Current or former (1)

Never smoker (0)
Cancer Extrathoracic cancer more than 5 years prior (1)

None (0)
Nodule Diameter
Spiculation Yes (1)

No (0)
Upper Lobe Yes (1)

No (0)
Malig Probability
Decimal Precision:
X = (0.0391 * Age) + (0.7917 * Smoker) + (1.3388 * Cancer) + (0.1274 * NoduleDiameter) + (1.0407 * Spiculation) + (0.7838 * UpperLobe) - 6.8272
MaligProbability = 100 * e(X) / ( 1 + e(X))
  • This clinical predictor is NOT validated or useful in patients who have had either prior lung cancer or some other cancer within the last 5 years.
  • Equation parameters such as Smoker have two or more discrete values that may be used in the calculation. The numbers in the parentheses, e.g. (1), represent the values that will be used.
  1. Swensen SJ, Silverstein MD, Ilstrup DM, et. al. The probability of malignancy in solitary pulmonary nodules. Application to small radiologically indeterminate nodules. Arch Intern Med. 1997 Apr 28;157(8):849-55.
Legal Notices and Disclaimer
All information contained in and produced by the MedCalc 3000 system is provided for educational purposes only. This information should not be used for the diagnosis or treatment of any health problem or disease. THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER. Click here for full notice and disclaimer.
MedCalc 3000 is Copyright © 1998-2011 Foundation Internet Services, LLC    [Build 244179 v11.2.2]