'Miliary metastasis' in a child with papillary thyroid cancer

Abstract

Lung disease with diffuse nodules has a broad differential diagnosis. We present a case of childhood papillary thyroid carcinoma with diffuse lung metastases in which the diagnosis was delayed due to fact that the diffuse nodules were considered to be pathognomonic of miliary tuberculosis. Diffuse nodular lung disease in children requires a careful diagnostic approach. The role of multidisciplinary involvement in these rare cases is invaluable.

Keywords: Paediatric oncology; Paediatrics; Respiratory medicine.

Figure 1

(A) Anteroposterior chest radiograph of the chest demonstrating diffuse, coarse lung nodules of varying size throughout the lung fields. The nodules extend to the lung periphery with a basal predominance and areas of confluence in the basal zones. At the level of the thoracic inlet the trachea is compressed from the right with lateral displacement. There is no evidence of compression of the main-stem bronchi or bronchus intermedius and no perihilar or subcarinal nodes are present. (B) Transverse contrasted CT chest (lung window); widespread, evenly distributed coarse pulmonary nodules of varying size (maximal size 6 mm) extend to the lung periphery. No ventilation defect, hilar or subcarinal lymph nodes are present. (C) transverse contrasted CT (mediastinal window) demonstrating an ill-defined mass in the right lobe of the thyroid with compression and lateral displacement of the tracheal.

Figure 2

(A) A low magnification image showing flat sheets with branching comprised of round-oval follicular cells. Papanicolaou stain, ×10. (B) Higher magnification image showing a flat sheet of crowded and overlapping follicular cells with pale chromatin features. Papanicolaou stain, ×40 (C) High magnification demonstrating the fine nuclear chromatin, with inconspicuous nucleoli and occasional intranuclear pseudo (top centre). All these features are consistent with papillary thyroid carcinoma. Papanicolaou stain, ×100.

Figure 3

Chest X-ray: Significant improvement of the miliary metastasis picture after the use of sorafenib. (b) Chest X-ray: Postsorafenib and RAI treatment chest X-ray demonstrating near to complete disappearance of the metastasis. RAI, radio-active iodine.