Searcharxiv⌕ Search

arXiv subjects

Sajad Jabarzadeh Ghandilu

Publications and source records attributed to Sajad Jabarzadeh Ghandilu.

3 recordsLinked to original sources

Polyp-D2ATL: Deep Domain-Adaptive Transfer Learning for Colorectal Polyp Classification under Label Distribution Shift

Early and highly accurate prediction of colorectal polyps, as an important sign of one of the most dangerous types of cancer, will result in saving more lives. Despite the advancements in colorectal polyp classification, many challenges remain in obtaining an automated polyp prediction system that is able to diagnose the difficult-to-predict polyps accompanied by different features in real scenarios, where the model can handle imbalanced data, label distribution shift, and cross-modality generalization successfully. In this study, we propose Polyp-D2ATL, a novel framework accompanied by a specific training strategy, which mitigates these limitations and effectively predicts the different classes of polyps belonging to the NICE classification. Our extensive experiments on the PICCOLO validation and test sets demonstrate that the proposed Polyp-D2ATL significantly outperforms existing state-of-the-art models across various reliable metrics, achieving an accuracy of 82.38%, a Macro-F1 of 77.49%, and a specificity of 87.47% on the validation set, alongside consistent improvements on the held-out test set which demonstrates the generalization capacity and clinical applicability of the proposed approach.

eess.IV↗

Semi-Supervised Radiomics for Glioblastoma IDH Mutation: Limited Labels, Data Sensitivity, and SHAP Interpretation

Glioblastoma (GBM) is an aggressive brain tumor in which IDH mutation status is a key prognostic biomarker, but traditional testing requires invasive biopsies, emphasizing the need for non-invasive approaches. In this multi-center study, we analyzed MRI sequences (T1, T2-weighted, contrast-enhanced T1, and FLAIR) from 1,329 patients across eight centers, with IDH labels available for 1,061 cases. A total of 1,223 radiomic features per case were extracted using PyRadiomics with Laplacian of Gaussian and wavelet filters, and both supervised learning (SL) and semi-supervised learning (SSL) frameworks were applied, incorporating 38 feature selection/attribute extraction strategies and 24 classifiers. Five-fold cross-validation was performed on UCSF-PDGM and UPENN datasets, and external validation on IvyGAP, TCGA-LGG, and TCGA-GBM, with SHAP analysis conducted for feature interpretability. Multimodal MRI fusion (T1+T2+T1CE+FLAIR) consistently outperformed single-sequence models. The best SSL model (RFE + SVM) achieved 0.93 cross-validation and 0.75 external accuracy, while the top SL model (RFE + Complement Naive Bayes) reached 0.90 and 0.80, respectively. SSL further demonstrated greater robustness to limited sample sizes, maintaining stable performance compared to SL, and SHAP analysis highlighted the amplified role of first-order Root Mean Square (T1CE) and wavelet-based features, strengthening biomarker interpretability. These findings indicate that SSL enhances accuracy, stability, and interpretability in MRI-based IDH prediction, with multimodal MRI fusion providing the most scalable and reliable strategy for non-invasive biomarker discovery in GBM.

physics.med-ph↗

Handcrafted vs. Deep Radiomics vs. Fusion vs. Deep Learning: A Comprehensive Review of Machine Learning -Based Cancer Outcome Prediction in PET and SPECT Imaging

Machine learning (ML), including deep learning (DL) and radiomics-based methods, is increasingly used for cancer outcome prediction with PET and SPECT imaging. However, the comparative performance of handcrafted radiomics features (HRF), deep radiomics features (DRF), DL models, and hybrid fusion approaches remains inconsistent across clinical applications. This systematic review analyzed 226 studies published from 2020 to 2025 that applied ML to PET or SPECT imaging for outcome prediction. Each study was evaluated using a 59-item framework covering dataset construction, feature extraction, validation methods, interpretability, and risk of bias. We extracted key details including model type, cancer site, imaging modality, and performance metrics such as accuracy and area under the curve (AUC). PET-based studies (95%) generally outperformed those using SPECT, likely due to higher spatial resolution and sensitivity. DRF models achieved the highest mean accuracy (0.862), while fusion models yielded the highest AUC (0.861). ANOVA confirmed significant differences in performance (accuracy: p=0.0006, AUC: p=0.0027). Common limitations included inadequate handling of class imbalance (59%), missing data (29%), and low population diversity (19%). Only 48% of studies adhered to IBSI standards. These findings highlight the need for standardized pipelines, improved data quality, and explainable AI to support clinical integration.

physics.med-ph↗