2018 Volume 58 Issue 7 Pages 975-979
Background. Minute pulmonary meningothelial-like nodule (MPMN) is incidentally detected in resected lung specimens. However, to date, its origin has remained unclear. Case. We report the case of 67-year-old woman with MPMN with deletion of the neurofibromatosis (NF)-2 gene, which was incidentally detected in a resected pulmonary adenocarcinoma specimen. She was suffering from dry cough and was referred to our hospital. CT revealed part-solid ground glass nodule (GGN) of 14 mm in size, which included a 6-mm solid part in the left S1+2 segment. She underwent left upper lobectomy under VATS according to intraoperative pathological diagnosis of minimally invasive adenocarcinoma. The postoperative pathological findings revealed the pulmonary lesion to be lepidic adenocarcinoma (pT1aN0M0 stage IA1). An MPMN lesion was also detected adjacent to the adenocarcinoma lesion. Postoperative immunohistochemistry revealed that the lesion was positive for epithelial membrane antigen (EMA), CD56, vimentin, and progesterone receptor (PgR). We also evaluated the status of the NF-2 gene using the FISH method, which revealed deletion of the NF-2 gene in the MPMN lesion. In the 18 months since surgery, the patient has been well without any recurrence of lung cancer, central nervous system (CNS) occurrence, or pulmonary meningioma. Conclusion. This mutational change of NF-2 in MPMN was previously reported to be similar to meningioma of the CNS. Our results are compatible with previous reports. Further studies are needed to elucidate the pathogenesis of this rare entity.
