Extraosseous benign notochordal cell tumor originating in the lung: a case report

Multiple benign notochordal cell tumors in lung with cystic change

Benign notochordal cell tumor (BNCT) is a benign lesion derived from notochordal cells. Although it is relatively common in intraosseous lesion, pulmonary BNCT is extremely rare. We present a case of 54-year-old male with multiple pulmonary nodules, in which were considered to be metastatic chordomas initially. For 20 months follow-up without any therapy, most of the nodules had no remarkable change but some nodules showed cystic change. We consulted with pathologists specializing in chordoma and the final diagnosis of the nodules was considered as BNCT rather than chordoma. We herein report the case of multiple pulmonary BNCTs with cystic change, comparing with previous reports.

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

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.

Benign notochordal cell tumor of the lung: Report of a case

A surgical case of a benign notochordal cell tumor of the lung is reported. The patient was an asymptomatic 41-year-old man, who was incidentally found to have a small tumor in the subpleural region of the left lingular segment. Since wedge resection of the tumor, the patient has been free from recurrence. The tumor measured 12 mm in diameter and showed a central cystic change. It consisted of a diffuse proliferation of polygonal cells with abundant, uni- or multi-vacuolated cytoplasm and bland nuclei. The tumor did not show a lobular architecture and lacked a myxoid or fibrous connective tissue containing blood vessels. In the peripheral region of the tumor, a small number of alveolar epithelial cells were entrapped. The nuclei of tumor cells were immunoreactive for brachyury, and the cytoplasm was positive for cytokeratin and S-100 protein. The entrapment of alveolar epithelial cells suggests infiltrative growth of the tumor, and the almost complete absence of blood vessels within the tumor may have restricted tumor growth and induced a cystic change in the central region.

Benign notochordal cell tumour: clinicopathology and molecular profiling of 13 cases

Aims

To study the clinicopathological and molecular features of benign notochordal cell tumours (BNCTs) and their differential diagnosis from chordoma.

Methods

13 cases of BNCT were investigated. The genome-wide copy number imbalances were performed using Oncoscan CNV array in three cases and fluorescence in situ hybridisation (FISH) detection of epidermal growth factor receptor (EGFR)/chromosome 7 enumeration probe (CEP7), LSI1p36/1q21, LSI19p13/19q13, CEP3/CEP12 and Telvysion 6 P was performed in 13 cases.

Results

All 13 BNCTs were symptomatic and eight cases showed a close relationship with the bones of the skull base. The important histological character for differential diagnosis with chordoma was the absence of extracellular matrix and eosinophil cells and the presence of vacuoles in most tumour cells. Immunohistochemical staining of AE1/AE3, vimentin, epithelial membrane antigen, S-100 and brachyury (100% each) were positive in BNCTs. Gain of chromosome 7 occurred in 10 cases (76.9%), gain of 1p in four (30.8%), gain of 1q in five (38.5%), gain of 19p and 19q in five (38.5%), gain of chromosome 12 in 11 cases (84.6%), gain of 6p in eight (61.5%) and gain of chromosome 3 in four cases (30.8%).

Conclusions

In contrast to chordoma, chromosome gain or normal copy number was more common while chromosome loss was infrequent in BNCTs. This may be a differential diagnosis clue for chordoma and may be an important characteristic in the progression of notochordal cell tumours.

Multiple primary chordomas of the lung

We here report the case of a 40-year-old man with primary pulmonary chordomas. Although an abnormality had been noted on a chest radiograph at age 26 years, the patient had not undergone further examination at that time because he was asymptomatic. Standard chest radiographs and computed tomography showed slow-growing, multiple bilateral pulmonary nodules. Two tumors were resected thoracoscopically to obtain a diagnosis. Pathologic examination resulted in a diagnosis of chordomas. Subsequent systemic examination revealed no additional lesions, not even in the axial skeleton. The patient is alive without any new lesions 38 months after surgery. These clinical and pathological findings suggest that our patient has multiple primary chordomas of the lung, which is an extremely rare condition.