Paraneoplastic Hypereosinophilia in Poorly Differentiated Adenocarcinoma of the Lung

Abstract

It is well-documented that lung and bronchus cancers are the leading cause of cancer death in the United States in both male and female patients, with lung adenocarcinoma accounting for the highest prevalence of lung cancers. Significant eosinophilia in the setting of lung adenocarcinoma has been documented in a few reports, being described as a rare paraneoplastic syndrome. We report on an 81-year-old female with hypereosinophilia-associated lung adenocarcinoma. A chest film showed a right lung mass, which was not apparent on a chest film 1 year prior, in the setting of significant leukocytosis of 27.90 x 10³/mm³ with eosinophilia of 6.40 x 10³/mm³. A computed tomography (CT) chest, obtained during admission, demonstrated significant right lower lobe mass enlargement since the previous study completed 5 months prior, with new occlusion of bronchi and pulmonary vessels to the region of the mass. Our observations are consistent with prior reports showing that the presence of eosinophilia in lung cancers may indicate rapid disease progression.

Keywords: hypereosinophilia; lung adenocarcinoma; paraneoplastic hypereosinophilia; paraneoplastic syndrome; poorly differentiated lung adenocarcinoma.

Figure 1. A: Upper right of image demonstrates tumor and lower left shows extensive inflammation. B: Demonstrating a higher magnification of the image in pane A, showing malignant features of non-small cell carcinoma; large pleomorphic cells with prominent nucleoli are seen. A large mitotic figure is shown (black arrow). C: Thyroid transcription factor-1 (TTF-1) immunohistochemical stain for lung adenocarcinoma, staining nuclei. D: Cytokeratin 7 (CK7) immunohistochemical stain for lung adenocarcinoma, staining cytoplasm.

Figure 2. A: Chest film from 363 days prior to hospital admission. B: Hospital chest film showing a large superior segment right lower lobe mass (red arrow).

Figure 3. A: CT chest from 132 days prior to hospital admission CT chest (seen in pane B), demonstrating a right lower lobe lung mass (red arrow). B: CT chest obtained on day 9 of hospital admission demonstrating a larger right lower lobe lung mass (red arrow).