Skip to main content
Dryad

Data from: Auditing shortcut learning and misclassification in AI-based breast cancer genomic subtyping

Data files

Sep 23, 2026 version files 199.47 MB

Click names to download individual files

Abstract

Objectives: To simulate shortcut learning mechanisms in AI-based breast cancer genomic subtyping and to develop an interpretable, reproducible framework capable of auditing feature over-reliance using a low-code environment.

Materials and Methods: A retrospective secondary analysis of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) dataset was conducted. A multinomial logistic regression model was trained on 691 complete cases using only clinical predictors (estrogen receptor [ER], progesterone receptor [PR], HER2 status, tumor stage, and age) to predict PAM50 molecular subtypes. A pseudo-SHAP (Shapley additive explanations) attribution method was implemented in Stata to estimate the marginal influence of each variable. Model performance was evaluated using McFadden’s pseudo-R² and validated by comparing pseudo-SHAP scores against canonical SHAP values derived in Python.

Results: The clinical-only model achieved a pseudo-R² of 0.396, indicating moderate explanatory power. PR and HER2 status were statistically significant predictors (P < .01) for Luminal B and HER2-enriched subtypes, respectively. The pseudo-SHAP framework identified disproportionate influence of these features (ΔP up to +0.29 for HER2-enriched). Correlation between pseudo-SHAP and SHAP values was strong (Spearman r = 0.91, P < .001), confirming method validity.

Discussion: Shortcut learning was evident, with the model over-relying on surrogate clinical biomarkers. Such behavior may distort biological interpretation and compromise clinical decision support reliability.

Conclusion: The pseudo-SHAP method provides a scalable, interpretable auditing framework for detecting shortcut learning in resource-constrained environments. Its application could enhance transparency and equity in AI models for precision oncology.