mayo_spn_risk: Mayo Clinic Model for Solitary Pulmonary Nodule Malignancy...

In cliot: Clinical Indices and Outcomes Tools

Mayo Clinic Model for Solitary Pulmonary Nodule Malignancy Risk

Description

Calculates the probability of malignancy in a solitary pulmonary nodule (SPN) based on the Mayo Clinic model. The model uses six independent predictors: age, smoking history, extrathoracic cancer history (>5 years prior), nodule diameter, upper lobe location, and spiculation.

Usage

mayo_spn_risk(age, smoking_history, cancer_history_gt_5y, nodule_diameter_mm,
              upper_lobe, spiculation)

Arguments

age	Numeric. Patient age in years.
smoking_history	Numeric (0 or 1). Current or former smoker. (1 = Yes).
cancer_history_gt_5y	Numeric (0 or 1). History of extrathoracic cancer diagnosed more than 5 years ago. (1 = Yes).
nodule_diameter_mm	Numeric. Diameter of the nodule in millimeters.
upper_lobe	Numeric (0 or 1). Is the nodule located in an upper lobe? (1 = Yes).
spiculation	Numeric (0 or 1). Does the nodule have spiculation on imaging? (1 = Yes).

Value

A list containing:

Mayo_Malignancy_Risk_Percent	The estimated percentage probability that the nodule is malignant.
Risk_Category	Classification of risk (Low <5%, Intermediate 5-65%, High >65%).

References

Swensen SJ, Silverstein MD, Ilstrup DM, Schleck CD, Edell ES. The probability of malignancy in solitary pulmonary nodules. Application to small radiologically indeterminate nodules. Arch Intern Med. 1997;157(8):849-855.

Examples

# Example 1: High Risk
# 70yo, Smoker, Hx Cancer, 20mm, Upper Lobe, Spiculated
# Log-odds = -6.8272 + 2.737 + 0.7917 + 1.3388 + 2.548 + 0.7838 + 1.0407 = 2.41
# Prob = e^2.41 / (1 + e^2.41) = ~91%
mayo_spn_risk(70, 1, 1, 20, 1, 1)

# Example 2: Low Risk
# 40yo, Non-smoker, No Hx, 5mm, Lower Lobe, Smooth
# Log-odds = -6.8272 + 1.564 + 0 + 0 + 0.637 + 0 + 0 = -4.62
# Prob = ~1%
mayo_spn_risk(40, 0, 0, 5, 0, 0)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.