Pulmonary tumor with Notochordal differentiation: a case report and morphologic, Immunohistochemical and molecular study of benign Notochordal cell tumor originating in the lung

Abstract

Background Extraosseous benign notochordal cell tumor is extremely rare, and there are only five reported cases worldwide. The presented case of pulmonary primary benign notochordal cell tumor is the sixth case, but the first to report the deletion mutation of EGFR gene exon 19. Case presentation The patient was a 50-year-old asymptomatic woman, who had been followed up for 3 years for a nodule in the right lung. After ten months of the wedge resection, the patient is alive without evidence of recurrence or metastasis. The tumor was 7 mm in diameter and was well demarcated. The tumor was consisted of a sheet of large round vacuolated cells with small and bland nuclei. No connective tissue containing blood vessels or inflammatory cell infiltration was detected in the stroma. The tumor was positive for CK AE1/AE3, Vimentin, S100 and Brachyury. EGFR gene mutation and amplification were not detected. Conclusions We firstly reported the positive immunohistochemical staining for EGFR and the negative molecular results of EGFR gene of pulmonary primary benign notochordal cell tumor. Due to the rarity of this tumor, more reports are needed to explore pathological characteristics, especially the molecular characteristics, in order to better understand the nature of tumors.

Cytohistological findings and diagnostic challenges in rare pediatric pulmonary mesenchymal malignancies: A report of two cases

“…5 These tumors are not specific to the lung and can occur anywhere in the body and in the lung the common sites are the tracheobronchial tree, pleura, chest wall, and mediastinum. 7 These patients can exhibit a wide range of symptoms, from being asymptomatic 9 There is no big dilemma in the diagnosis of IMT from histopathology sections. But with the increasing utilization of cytology samples in the diagnosis of lung tumors these days, cytology has become the first-line diagnostic tool in pulmonary tumors whenever feasible.…”

“…Ki67 index is usually low in IMT, but an increase from the previous rate may denote malignant transformation. In one study by Stoll and Li on 20 patients with IMTs, a diagnosis of IMT could be given in only 15% of patients based on cytology alone 9 . There is no big dilemma in the diagnosis of IMT from histopathology sections.…”

Multiple benign notochordal cell tumors in lung with cystic change

“…BNCT is relatively common in intraosseous lesion being found in 20% of adults at autopsy [1] , while extraosseous BNCT is extremely rare and only reported in lung. There are only 6 cases via Pubmed [ [2] , [3] , [4] , 6 , 7 ] and one in the Japanese journal reported so far [5] , after first reported by Kikuchi et al in 2011. Six cases of pulmonary BNCT presented solitary nodule and only 1 case reported by Lee et al.…”

“…In the previous reports, pulmonary BNCTs have been described as round and regular shape and shown up to 15 mm in diameter. The nodules have mostly located in subpleural area [7] . Similar to the previous reports, the nodules in our case were 14 mm for maximum size and mostly detected in the peripheral area, however some nodules have located in the central area and shown cystic change.…”

“…BNCT is a benign lesion derived from notochordal cells and it is relatively common in intraosseous lesion, being found in 20% of adults at autopsy [1] . Although some cases of BNCT arising in lung has been reported recently [2] , [3] , [4] , [5] , [6] , [7] , there is no report of multiple pulmonary BNCTs. We present a case of 54-year-old male with multiple pulmonary nodules showing cystic change and finally diagnosed of pulmonary BNCT.…”