Abstract Miliary metastasis refers to the hematogenous dissemination of malignant cells resulting in innumerable, uniformly distributed micronodules throughout the lungs. Although most commonly associated with adenocarcinoma of the lung, it can be mistaken for infectious etiologies such as miliary tuberculosis. Early recognition is crucial, as this pattern indicates advanced disease and poor prognosis. A 57-year-old man with a history of diabetes mellitus, coronary artery disease, stage V chronic kidney disease, and previously treated stage IV squamous-cell carcinoma of the tongue presented with a 48-hour history of confusion. A “code stroke” was activated, and brain imaging excluded infarction, however Computed Tomography Angiography (CTA) of the head and neck incidentally revealed bilateral apical nodular densities and patchy consolidations, initially concerning for miliary tuberculosis. Subsequent non-contrast CT of the chest demonstrated a 4.6 cm left upper-lobe mass with innumerable sub-centimeter nodules diffusely involving both lungs. A chest CT from October 2023 revealed a stable 2.5 × 1.4 cm left upper-lobe nodule with low metabolic activity on Positron Emission Tomography (PET) (SUVmax 1.5). Given the patient’s history of squamous cell carcinoma of the tongue, the lesion was presumed related and was not biopsied. Infectious studies, including tuberculosis testing, were negative. Bronchoscopy with bronchoalveolar lavage (BAL) of the right upper lobe and random transbronchial biopsy of the left upper lobe were performed. BAL cytology revealed non-small-cell carcinoma, and histopathology confirmed adenocarcinoma. Given the patient’s poor functional status, rapid radiographic progression, and multiple comorbidities, he was determined not to be a candidate for disease-directed therapy, and discussions with palliative care regarding hospice were pursued. This case highlights miliary metastasis as an uncommon but critical manifestation of advanced lung adenocarcinoma. Miliary pulmonary metastases occur through hematogenous spread of malignant cells, most often from adenocarcinomas. This radiologic pattern is strongly associated with Epidermal Growth Factor Receptor (EGFR)-mutated non-small-cell lung cancer and portends an unfavorable prognosis. It must be differentiated from infectious etiologies and from lymphangitic carcinomatosis, which involves tumor spread along pulmonary lymphatics and is characterized by interlobular septal thickening, bronchovascular bundle involvement, and reticular opacities rather than discrete micronodules. Recognition of the miliary pattern, particularly in patients with prior malignancy, should prompt timely tissue diagnosis, as it is associated with advanced disease burden and poor prognosis, and typically prompts early palliative-care consultation. This abstract is funded by: none
Desai et al. (Fri,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: