Department of Pathology, The Second Affiliated Hospital Zhejiang University School of Medicine, Hangzhou, China.
Diagn Pathol. 2021 Oct 30;16(1):99. doi: 10.1186/s13000-021-01157-5.
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.
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.
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.
骨外良性脊索细胞肿瘤极为罕见，全世界仅报道了 5 例。本研究报告的首例肺原发性良性脊索细胞肿瘤为第 6 例，但首次报道了 EGFR 基因外显子 19 的缺失突变。
患者为 50 岁无症状女性，因右肺结节随访 3 年。楔形切除术后 10 个月，患者存活，无复发或转移证据。肿瘤直径 7mm，边界清楚。肿瘤由大片大圆形空泡细胞组成，细胞核小而温和。间质中无血管或炎性细胞浸润的结缔组织。肿瘤 CK AE1/AE3、波形蛋白、S100 和 Brachyury 阳性。未检测到 EGFR 基因突变和扩增。
我们首次报道了肺原发性良性脊索细胞肿瘤 EGFR 的免疫组织化学染色阳性和 EGFR 基因的分子检测结果为阴性。由于该肿瘤罕见，需要更多的报道来探讨其病理特征，尤其是分子特征，以便更好地了解肿瘤的性质。
