[Pulmonary microcystic fibromyxoma: report of a case with review of literature].

ABSTRACT

Objective: To study the clinicopathologic features, diagnosis and differential diagnosis of pulmonary microcystic fibromyxoma. Methods: In March 2014, at the First Affiliated Hospital to Nanjing Medical University a 58-year-old female patient of pulmonary microcystic fibromyxoma was collected. The clinicopathologic, immunohistochemical and genetic profile of a case of pulmonary microcystic fibromyxoma were studied, and the relevant literature reviewed. Results: The patient was a 58-year-old female who presented with cough and sputum for 1 month. CT scan disclosed a 15 mm nodule in her right middle lobe of lung. The patient underwent a wedge resection with negative margin. Grossly, a well-demarcated peripheral lung nodule was detected, measuring 1.5 cm×1.5 cm×1.0 cm, with myxoid tan-white cut surface containing microcysts. Microscopically, the tumor was composed of bland spindled to stellate-shaped cells widely spaced within prominent fibromyxoid stroma with prominent cystic change. No mitosis or necrosis was present. There were inconspicuous slim curvilinear capillaries and occasional collection of stromal lymphocytes and plasma cells. Immunohistochemically, the tumor cells were positive for vimentin, but negative for CD34, SMA, desmin, S-100 protein, ALK, CKpan, EMA, calretinin and TTF1. Fluorescence in situ hybridization did not show chromosomal translocation involving EWSR1, DDIT3 or FUS genes. The patient was recurrence or metastasis free after follow-up for 38 months. Conclusion: Pulmonary microcystic fibromyxoma is a rare benign lesion that should be differentiated from other lung tumors with myxoid characteristics.