Saudi Journal of Radiology
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Saudi Journal of Radiology

Volume 4, 2025 · Issue Proceeding of the 16th Annual Meeting of Radiology Society of Saudi Arabia (RSSA) · Open Access · Double-blind Peer-review

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Original Research Article

From Mimic to Diagnosis: Primary Lung Adenocarcinoma Presenting as Peripheral Airspace Opacities Mimicking Organizing Pneumonia

Mutaz Khairo1, Dania Felemban2, Saja Hafiz3, Hadeel AlQurashi4, Isra Khallaf 5 & May Alsharif6

1 Thoracic and Abdominal Consultant Radiologist, Department of Medical Imaging and Intervention, King Abdullah Medical City (KAMC), Makkah, Saudi Arabia.

2 Radiology Resident, Department of Medical Imaging and Intervention, King Abdullah Medical City (KAMC), Makkah, Saudi Arabia

3 Radiology Associate Consultant, Department of Medical Imaging and Intervention, King Abdullah Medical City (KAMC), Makkah, Saudi Arabia

Published: 05 May 2026

https://doi.org/10.55038/qrm6h705
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Abstract
Lung adenocarcinoma may occasionally present with radiographic features resembling organizing pneumonia (OP), resulting in diagnostic uncertainty, delayed recognition, and the risk of inappropriate management. We present a case of a 77-year-old man with diabetes mellitus, hypertension, and ischemic heart disease who developed bilateral pulmonary infiltrates. Radiological findings initially suggested OP; however, histopathological examination revealed a moderately differentiated mucinous adenocarcinoma favoring a primary lung tumor. This case underscores a significant diagnostic pitfall and highlights the necessity of histological confirmation when encountering atypical radiologic features.
KeywordsLung AdenocarcinomaInvasive Mucinous AdenocarcinomaOrganizing PneumoniaOP-like PatternRadiologic–Pathologic CorrelationDiagnostic Pitfall

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