Concurrent pulmonary benign metastasizing leiomyoma and primary lung adenocarcinoma: a case report

Abstract

Benign metastasizing leiomyoma (BML) in the lung is a very rare metastatic disease. BML accompanied with primary lung cancer is even more uncommon. In our report, a 38-year-old female who undertook routine computed tomography (CT) scan revealed the pulmonary abnormality. Chest CT imaging showed a ground-glass opacity (GGO) nodule coexisted with a solid mass, which was prone to be diagnosed as a primary lung cancer with metastasis. However, the pathological immunohistochemical staining result proved the diagnosis of BML accompany with primary lung adenocarcinoma. Our case presented a valuable report for radiologist and clinician to identify the diagnosis and differentiated diagnosis, and understand the pathogenesis, treatment and prognosis of the tumor in further.

Keywords: Benign metastasizing leiomyoma (BML); adenocarcinoma; lung.

Figure 1

Chest CT imaging of the lung tumour in the left upper and lower lobes. (A) Chest CT scan shows a well-defined ground glass opacity (GGO) nodule (arrow) of 0.7 cm in size. (B,C) Axical CT scan (lung window, mediastinum window) shows a soft tissue mass (arrow) of 3.4 cm × 3.1 cm in size (arrow).

Figure 2

Histopathology of the lung tumour in the left lower lobe. (A) Pathological examination of the GGO shows a localized micro-invasive adenocarcinoma (MIA) with mild hyperplasia of peripheral alveolar epithelium (hematoxylin and eosin staining, ×100). (B,C) Histopathological finding of the mass. Hematoxylin and eosin staining showed a well boundary nodule (B, ×40) and spindle-shaped smooth muscle cells (C, ×40). (D,E,F,G,H) Immunohistochemical staining showed diffuse and strong positivity throughout the pulmonary tumor for smooth muscle actin (SMA) (D), caldesmon (E), desmin (F), estrogen receptor (G) and progesterone receptor (H) (×100). GGO, ground-glass opacity.