A surgical case of pulmonary adenocarcinoma in the right upper lobe associated with a systemic artery-to-pulmonary artery fistula

Abstract

A 52-year-old female never-smoker with an abnormal shadow in the right lung detected on radiography was referred to our institution. Contrast-enhanced computed tomography revealed an irregular nodule in the upper lobe of the right lung, suggestive of a pulmonary vascular abnormality. Angiography revealed a direct communication between the right internal mammary artery (IMA) and the right upper lobe pulmonary artery branches, with dilated and tortuous vascular proliferation. As multiple branch arteries were seen flowing into the upper lobe from the IMA, transcatheter selective embolization of these vessels and right upper lobectomy by video-assisted thoracoscopic surgery were performed. Contrary to the clinical diagnosis, the pathological finding was a pulmonary adenocarcinoma of the right upper lobe. Additional lymph node dissection was performed later. We report an extremely rare and unprecedented case of pulmonary adenocarcinoma fed by the right IMA, with a literature review.

Keywords: lung cancer; selective arterial embolization; systemic artery-to-pulmonary artery fistulas.

FIGURE 1

(a) Computed tomography (CT) showing a 31‐mm irregular nodule in the anterior segment (S3) of the upper lobe of the right lung (white arrow). (b) Contrast‐enhanced CT showed a tubular structure (white arrow).

FIGURE 2

(a) Right pulmonary arteriography showed pulmonary arteries distributed around the lesion, but no arteriovenous shunt was observed. (b) Selective right internal mammary arteriography showed markedly dilated tortuous vascular growth and communication with the right pulmonary artery. IMA, internal mammary artery, PA, pulmonary artery, PV, pulmonary vein. (c) After embolization of the branch of the internal mammary and distal feeders to the fistula, only minimal filling of the network of aberrant blood vessels was identified. No filling of the pulmonary artery was seen.

FIGURE 3

(a) Thoracoscopic findings showed that the right upper lobe was adherent to the anterior mediastinum. PV, pulmonary vein. (b) Microscopic findings of papillary adenocarcinoma. Scale bar, 200 μm. (c) Macroscopic findings in the right upper lobe and anterior mediastinal adipose tissue. A right medial mammary artery fragment can be seen (arrowhead). (d) Pulmonary adenocarcinoma (arrow) and right internal mammary artery inflow (arrowhead) were observed in a loupe view using hematoxylin–eosin staining.