18FDG PET/CT is sensitive but not specific for malignancy: two cases of disseminated tuberculosis mimicking metastatic cancer on imaging and clinical presentation

Maxime Collin; Bruno Krug; Marie-Cécile Nollevaux; Fanny Collette; Quentin Gilliaux; Laurence Faugeras; Lionel D'Hondt

doi:10.12890/2025_005475

DOI: 10.12890/2025_005475

18FDG PET/CT is sensitive but not specific for malignancy: two cases of disseminated tuberculosis mimicking metastatic cancer on imaging and clinical presentation

Authors

Maxime Collin Department of Oncology, CHU UCL Namur – site Godinne, Yvoir, Belgium
Bruno Krug Department of Nuclear Medicine, CHU UCL Namur – site Godinne, Yvoir, Belgium
Marie-Cécile Nollevaux Department of Pathology, CHU UCL Namur – site Godinne, Yvoir, Belgium
Fanny Collette Department of Oncology, CHU UCL Namur – site Godinne, Yvoir, Belgium
Quentin Gilliaux Department of Oncology, CHU UCL Namur – site Godinne, Yvoir, Belgium
Laurence Faugeras Department of Oncology, CHU UCL Namur – site Godinne, Yvoir, Belgium
Lionel D'Hondt Department of Oncology, CHU UCL Namur – site Godinne, Yvoir, Belgium

maxime.collin@student.uliege.be

Keywords

Metastases, tuberculosis, 18FDG PET/CT, misleading diagnosis, case series

Abstract

Introduction: ¹⁸Fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG PET/CT) scan is widely used in the evaluation of suspected tumoral processes. In addition to its oncological applications, it is also employed in the diagnosis and follow-up of various conditions, including multiorgan tuberculosis.
Case description: We report a case series of two young patients with exclusive extrapulmonary disseminated tuberculosis that mimicked a neoplastic process both clinically and on ¹⁸FDG PET/CT imaging. Initially, both patients were admitted to the oncology unit with a presumed diagnosis of cancer. However, following an exhaustive work-up, a definitive diagnosis of tuberculosis was established via histopathological and microbiological analysis.
Conclusion: These cases underscore the importance of considering disseminated tuberculosis as a differential diagnosis during oncologic evaluations, especially in patients from endemic regions, and highlight the potential psychological impact of prematurely labelling a condition as cancer.

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References

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Published

2025-06-11

Issue

Vol. 12 No. 7 (2025)

How to Cite

1.

Collin M, Krug B, Nollevaux M-C, Collette F, Gilliaux Q, Faugeras L, et al. 18FDG PET/CT is sensitive but not specific for malignancy: two cases of disseminated tuberculosis mimicking metastatic cancer on imaging and clinical presentation. EJCRIM [Internet]. 2025 Jun. 11 [cited 2026 Nov. 3];12(7). Available from: https://ejcrim.com/index.php/ejcrim/article/view/5475