Privacy-Preserving Quantum Federated Learning for mammographic breast cancer screening in African and MENA populations — HQCNN + simulated QFL with differential privacy, uncertainty quantification, and cross-population external validation.
# Privacy-Preserving Quantum Federated Learning for Breast Cancer Screening
### African and MENA Population Contexts
> Global Health Artificial Intelligence and Computing Laboratory - KCCR, KNUST, Ghana.
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## Overview
This project implements a hybrid quantum-classical neural network (HQCNN)
within a simulated Quantum Federated Learning (QFL) framework for
privacy-preserving breast cancer screening. Three virtual Ghanaian hospital
clients (Accra, Kumasi, Tamale) train locally; only VQC parameters are
aggregated — raw patient data never leaves any node.
## Key contributions
- First QFL pipeline benchmarked on African mammography data
- HQCNN: MobileNetV2 feature extractor + Variational Quantum Circuit (9–25 params)
- Differential privacy simulation (σ_dp sweep) with privacy-utility trade-off analysis
- Uncertainty quantification: MC-Dropout + quantum shot variance
- Cross-population external validation: SA → MENA generalisation gap
- Temperature scaling for VQC calibration (ECE correction)
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## Repository Structure
```
ppqfl-breast-cancer-screening/
│
├── _1_eda.py # Phase 1: Data audit & EDA (Mendeley + KAU-BCMD)
├── _2a_baseline.py # Phase 2a: MobileNetV2 classical baseline
├── _2b_feature_pca.py # Phase 2b: Feature extraction + PCA → quantum bridge
├── _3_5_vqc.py # Phases 3–5: VQC design, Regime A/B, sweep, noise
├── _6_7_uq.py # Phases 6–7: Uncertainty quantification + temperature scaling
├── _8_9_qfl.py # Phases 8–9: Simulated QFL + differential privacy
├── _10_11_external_val.py # Phases 10–11: KAU external validation + ablation table
│
├── cache_check.py # Pipeline cache guard (skip completed stages)
├── run_pipeline.sh # Full pipeline orchestrator (nohup / screen ready)
├── setup_local.sh # Local machine setup (path migration + deps)
│
├── requirements.txt # Pi …