Radiology. Imaging cancer最新文献

Purpose To evaluate an MRI-based strategy for quantifying intra- and peritumoral heterogeneity (ITH and PTH) in hepatocellular carcinoma (HCC) and develop ITH- and PTH-based models for diagnosing microvascular invasion (MVI) and stratifying prognostic risk. Materials and Methods Patients with HCC (≤5 cm) were retrospectively included from three different institutions from March 2012 to September 2023 and divided into internal training, internal testing, and external testing cohorts. Tumor and peritumoral tissues in MR images were categorized into distinct habitats using unsupervised clustering algorithms. High-throughput radiomic features were extracted from each habitat. The degree of feature variation within each habitat was quantified to derive characteristics representing ITH and PTH. Engineered features were developed to train machine learning models for MVI diagnosis. Kaplan-Meier survival curves and Cox regression analysis were used for survival analysis. Results A total of 432 patients (mean age, 54.31 years ± 11.15 [SD]; 371 male) were included. The TH_DNN model, constructed using ITH- and PTH-based quantitative features combined with a deep neural network (DNN), demonstrated the best predictive performance for MVI across the three datasets (area under the receiver operating characteristic curve range = 0.82-0.99). The subgroup predicted as MVI positive with the TH_DNN model exhibited a poorer prognosis than the MVI-negative subgroup. In terms of overall survival and postoperative recurrence, the hazard ratios for MVI diagnosis were 2.79 (95% CI: 1.35, 5.75; P = .006) and 2.17 (95% CI: 1.38, 3.43; P < .001), respectively. Conclusion This study developed a strategy for quantifying ITH and PTH, which was valuable for noninvasive and accurate identification of MVI and prognostic risk in patients with HCC. Keywords: Liver, MRI, Oncology, Hepatocellular Carcinoma, Microvascular Invasion, Tumor habitat, Intratumoral Heterogeneity, Peritumoral Heterogeneity Supplemental material is available for this article. © The Author(s) 2025. Published by the Radiological Society of North America under a CC BY 4.0 license.

Purpose To determine whether bimodal US improves prediction of pathologic complete response following neoadjuvant chemotherapy (NAC) compared with MRI, as well as to assess the diagnostic value of a combined imaging model. Materials and Methods In this prospective two-center study, participants with primary breast cancer undergoing NAC between January 2020 and January 2024 were enrolled. Preoperative bimodal US (grayscale and shear wave) and MRI data were collected. Complete response on US (uCR) and MR images (mCR) were defined by radiologists. Diagnostic models based on uCR, mCR, and their combination were evaluated using postsurgical pathology as the reference standard. Pathologic complete response was defined as no residual tumor (ypT0) or no invasive cancer with possible ductal carcinoma in situ (ypT0/Tis). Model performance was evaluated by area under the receiver operating characteristic curve (AUC), with sensitivity, specificity, positive and negative likelihood ratios, and comparisons by the DeLong test. All tests were two-sided (P < .05). Results A total of 224 female participants (median age, 46 years; IQR, 38.75-56) with breast cancer undergoing NAC were included. Overall, 82 of 224 (37%) achieved ypT0/Tis, and 62 of 224 (28%) achieved ypT0. Using ypT0/Tis as the pathologic complete response standard, the uCR model achieved an AUC of 0.76 (95% CI: 0.67, 0.83), while the mCR model achieved an AUC of 0.80 (95% CI: 0.71, 0.87). Using ypT0, the uCR model achieved an AUC of 0.79 (95% CI: 0.70, 0.86), and the mCR model an AUC of 0.75 (95% CI: 0.65, 0.82) in the test set. The combined imaging model (ypT0/Tis, AUC = 0.87; ypT0, AUC = 0.87) outperformed both the uCR (ypT0/Tis, P = .002; ypT0, P = .002) and mCR models (ypT0/Tis, P = .04; ypT0, P = .004). Conclusion Bimodal US effectively predicted pathologic response to NAC in breast cancer with accuracy comparable to MRI. A combined US/MRI model demonstrated higher diagnostic performance than either modality alone. Keywords: Breast, Ultrasound Chinese Clinical Trial Registry (ChiCTR2400085035) Supplemental material is available for this article. © RSNA, 2025 See also commentary by Horvat and Fazzio in this issue.

Meningiomas are the most common primary central nervous system tumors, arising from arachnoid cap cells and typically following a benign clinical course. However, a minority of cases-particularly higher-grade meningiomas-exhibit aggressive behavior, including local invasion, recurrence, and, in rare instances, extracranial metastasis. Metastatic meningioma, defined as dissemination beyond the cranial and spinal compartments, remains exceptionally uncommon, with reported incidence ranging from 0.1% to 0.76%. Common metastatic sites include the lungs, bone, liver, and lymph nodes, although virtually any organ may be involved. Proposed mechanisms of spread include hematogenous dissemination via venous sinuses, cerebrospinal fluid seeding in high-grade variants, and possibly lymphatic dissemination. Imaging features that suggest metastatic potential include irregular margins, heterogeneous enhancement, prominent peritumoral edema, and bone destruction. Advanced modalities, such as gallium 68 DOTA-Tyr3-octreotide PET/CT and fluorine 18 fluorodeoxyglucose PET, play an increasing role in detecting and characterizing both known and occult metastatic lesions. Molecular alterations, including TERT promoter mutations, CDKN2A/B deletions, and somatostatin receptor 2 overexpression, are increasingly recognized as important markers for risk stratification and targeted therapy selection. Management requires a multimodal approach, including surgery, radiation therapy, and emerging systemic options such as peptide receptor radionuclide therapy and immune checkpoint inhibitors. Given the rarity and clinical complexity of this entity, radiologists must maintain a high index of suspicion, particularly while evaluating in high-grade or recurrent meningiomas. Keywords: Meninges, Brain/Brain Stem, Neuro-oncology, Molecular Imaging, Metastatic Meningioma, DOTATATE, High-Grade Meningioma, Somatostatin Receptor Imaging, SSTR, Peptide Receptor Radionuclide Therapy © RSNA, 2025.

The global cancer burden is increasing, with disproportionate morbidity and mortality in low- and middle-income countries. Imaging is essential for cancer diagnosis, staging, and follow-up, yet access in these settings remains poor. Barriers include insufficient availability of appropriate equipment, shortages of trained personnel, limited interventional services, and socioeconomic constraints. This review examines these barriers and challenges in global access to imaging for common cancers such as breast, lung, prostate, and hepatocellular carcinoma. Potential solutions are discussed, including innovations such as fit-for-purpose imaging hardware, artificial intelligence-assisted image interpretation, and governmental, policy, and international initiatives aimed at improving cancer imaging access in low- and middle-income countries. Keywords: Multimodal Applications, CT, Ultrasound, MRI, Artificial Intelligence, PET/CT © RSNA, 2025.