Whole-body low-dose CT can be of value in prostate cancer decision-making: a retrospective study on 601 patients

• Published in: Insights into imaging Vol. 14; no. 1; p. 124
• Main Authors: Chavoshi, Mohammadreza, Mirshahvalad, Seyed Ali, Zamani, Sara, Radmard, Amir Reza, Fallahi, Babak, Mousavi, Seyed Asadollah
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 16.07.2023; Springer Nature B.V; SpringerOpen
• Subjects: 68Ga-PSMA; Bone; Computed tomography; Criteria; Decision making; Diagnostic Radiology; Diagnostic systems; Imaging; Internal Medicine; Interventional Radiology; Lesions; Medicine; Medicine & Public Health; Metastasis; Neuroradiology; Nuclear medicine; Original; Original Article; Patients; Positron emission; Prostate; Prostate cancer; Radiology; Ultrasound; Ga-PSMA; Bone; Metastasis; Computed tomography; Prostate; 68Ga-PSMA
• ISSN: 1869-4101; 1869-4101
• DOI: 10.1186/s13244-023-01475-w

Objectives To evaluate the diagnostic value of whole-body low-dose computed tomography (CT) to detect bone metastasis in prostate cancer (PCa) patients and its possible utility in therapeutic decision-making. Also, to determine the valuable CT features for lesion characterisation. Methods This IRB-approved retrospective study reviewed PCa patients who underwent 68 Ga-PSMA PET/CT in our centre from March 2017 to August 2022. Two board-certified radiologists and one nuclear medicine specialist reported all whole-body low-dose CT scans separately, unaware of the 68 Ga-PSMA-PET results. The per-lesion and per-patient diagnostic performances were calculated. Also, the significance of CT features was evaluated. Moreover, the inter-observer agreement was analysed. A two-tailed p value < 0.05 was considered significant. Results From 727 reviewed PCa patients, 601 (mean age = 68.7 ± 8.1) were found to be eligible, including 211 (35.1%) referrals for initial staging and 390 (64.9%) for evaluating the extent of the disease after biochemical recurrence. Per-patient diagnostic analysis for three reviewers showed 81.0–89.4% sensitivity and 96.6–98.5% specificity in detecting osteo-metastasis. It was able to correctly detect high-burden disease based on both CHAARTED and LATITUDE criteria. Regarding the value of underlying CT features, size > 1 cm, ill-defined borders, presence of soft-tissue component, and cortical destruction were statistically in favour of metastasis. Also, Hu > 900 was in favour of benign entities with 93% specificity. Conclusions Although not as accurate as 68 Ga-PSMA PET/CT, whole-body low-dose CT might precisely classify PCa patients considering therapeutic decision-making. Additionally, we proposed diagnostic CT features that could help radiologists with better characterisation of the detected lesions. Critical relevance statement The whole-body low-dose CT can be considered valuable in the clinical decision-making of prostate cancer patients. This modality may obviate performing multiple imaging sessions and high-cost scans in patients diagnosed with the high-burden disease. Graphical abstract Key points The whole-body CT showed 81.0%-89.4% sensitivity and 96.6–98.5% specificity in detecting osteo-metastases. The whole-body CT could detect high-burden disease considering CHAARTED and LATITUDE criteria. Regarding CT features, lesions with Hu>900 were found benign with 93% specificity.