Quantitative CT Attenuation Cut-off Values for Lesion Characterization: Enostoses in Patients Without Malignancy Versus Osteoblastic Metastases in Breast Cancer

Authors

  • Novita Pitri Department of Radiology, Faculty of Medicine, Universitas Pelita Harapan, Jakarta, Indonesia
  • Mathelda Diah Wulandari Department of Radiology, Faculty of Medicine, Universitas Pelita Harapan, Jakarta, Indonesia
  • Dario Agustino Nelwan Department of Radiology, Faculty of Medicine, Universitas Hasanuddin, Makassar, Indonesia
  • Patricia Jorisal Department of Radiology, Faculty of Medicine, Universitas Pelita Harapan, Jakarta, Indonesia
  • Ivana Dewi Mulyanto Department of Nuclear Medicine, Faculty of Medicine, Universitas Pelita Harapan, Jakarta, Indonesia
  • Ratna Sari Wijaya Faculty of Medicine, Universitas Pelita Harapan, Jakarta, Indonesia

DOI:

https://doi.org/10.19166/med.v15i2.10792

Keywords:

Enostoses, Osteoblastic metastases, Breast cancer, Housefield unit, CT attenuation

Abstract

Background:

Incidental osteoblastic bone lesions detected on CT scans, such as enostoses and osteoblastic metastases, often pose diagnostic challenges, especially in patients with or without a history of breast cancer. Hounsfield unit (HU) attenuation values have been proposed to differentiate these lesions non-invasively, however, variability in cut-off values exists in prior studies.

 

Methods:

This observational analytic case-control study included adult patients who underwent CT and FDG PET-CT at MRCCC Siloam Semanggi Hospital, Jakarta from 2020 to 2025. Controls were patients with enostoses and no history of malignancy, while cases were breast cancer patients with PET/CT-confirmed osteoblastic metastases. Mean and maximum HU values were measured and analyzed to determine optimal cut-offs.

 

Result:

Mean and maximum HU values were significantly higher in enostoses than in osteoblastic metastases (mean: 1025 ± 123.66 vs. 449.65 ± 106.93; maximum: 1167.77 ± 106.20 vs. 599.34 ± 134.78; p < 0.001). A mean HU cut-off of 692 achieved 100% sensitivity, 98.36% specificity, and an AUC of 0.992. A maximum HU cut-off of 860 showed 79.61% sensitivity, 100% specificity, and an AUC of 0.898.

 

Conclusions:

Mean and maximum HU values on CT are highly effective for differentiating enostoses from osteoblastic metastases in breast cancer patients.

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Published

2026-03-10

How to Cite

Pitri, N., Wulandari, M. D., Nelwan, D. A., Jorisal, P., Mulyanto, I. D., & Wijaya, R. S. (2026). Quantitative CT Attenuation Cut-off Values for Lesion Characterization: Enostoses in Patients Without Malignancy Versus Osteoblastic Metastases in Breast Cancer. Medicinus, 15(2), 24–32. https://doi.org/10.19166/med.v15i2.10792

Issue

Vol. 15 No. 2 (2026): February

Section

Clinical Research

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Copyright (c) 2026 Novita Pitri, Mathelda Diah Wulandari, Dario Agustino Nelwan, Patricia Jorisal, Ivana Dewi Mulyanto, Ratna Sari Wijaya

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