Case Report

Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy

Volume: 6 Number: 2 July 30, 2026

Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy

Abstract

Brown tumors are rare benign skeletal manifestations of hyperparathyroidism that may demonstrate intense 18F-FDG uptake and mimic metastatic bone disease on PET/CT. We report a case of primary hyperparathyroidism with markedly elevated parathyroid hormone levels and hypercalcemia. Prior Tc-99m sestamibi dual-phase parathyroid scintigraphy with subtraction imaging demonstrated persistent radiotracer retention in the right inferior parathyroid region, consistent with parathyroid adenoma. Bone scintigraphy suggested a metabolic bone process rather than metastatic disease, whereas subsequent 18F-FDG PET/CT revealed multiple intensely hypermetabolic skeletal lesions concerning for widespread metastases. In contrast, the suspected parathyroid lesion showed relatively low FDG uptake. Correlation of multimodality nuclear imaging findings with biochemical parameters favored the diagnosis of brown tumors, which was confirmed histopathologically as parathyroid adenoma. This case highlights the importance of integrating PET/CT, scintigraphic, and laboratory findings to avoid misinterpretation of FDG-avid skeletal lesions and unnecessary oncologic management.

Keywords

References

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Details

Primary Language

English

Subjects

Nuclear Medicine

Journal Section

Case Report

Publication Date

July 30, 2026

Submission Date

May 22, 2026

Acceptance Date

June 20, 2026

Published in Issue

Year 2026 Volume: 6 Number: 2

APA
Övüt, A. R., & Çiçekli, A. (2026). Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy. Molecular Oncologic Imaging, 6(2). https://doi.org/10.71286/moi.1957104
AMA
1.Övüt AR, Çiçekli A. Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy. Molecular Oncologic Imaging. 2026;6(2). doi:10.71286/moi.1957104
Chicago
Övüt, Ayşe Rana, and Ali Çiçekli. 2026. “Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET CT and Bone Scintigraphy”. Molecular Oncologic Imaging 6 (2). https://doi.org/10.71286/moi.1957104.
EndNote
Övüt AR, Çiçekli A (July 1, 2026) Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy. Molecular Oncologic Imaging 6 2
IEEE
[1]A. R. Övüt and A. Çiçekli, “Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy”, Molecular Oncologic Imaging, vol. 6, no. 2, July 2026, doi: 10.71286/moi.1957104.
ISNAD
Övüt, Ayşe Rana - Çiçekli, Ali. “Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET CT and Bone Scintigraphy”. Molecular Oncologic Imaging 6/2 (July 1, 2026). https://doi.org/10.71286/moi.1957104.
JAMA
1.Övüt AR, Çiçekli A. Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy. Molecular Oncologic Imaging. 2026;6. doi:10.71286/moi.1957104.
MLA
Övüt, Ayşe Rana, and Ali Çiçekli. “Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET CT and Bone Scintigraphy”. Molecular Oncologic Imaging, vol. 6, no. 2, July 2026, doi:10.71286/moi.1957104.
Vancouver
1.Ayşe Rana Övüt, Ali Çiçekli. Brown Tumors Mimicking Diffuse Skeletal Metastases on F-18 FDG PET/CT and Bone Scintigraphy. Molecular Oncologic Imaging. 2026 Jul. 1;6(2). doi:10.71286/moi.1957104