2003 Volume 43 Issue 4 Pages 351-355
Background. Well differentiated fetal adenocarcinoma (WDFA) is a very rare lung tumor, and there have been very few studies reporting genetic mutations in the development of this type of tumor. Case. A 38-year-old man was admitted to our hospital for investigation of an abnormal shadow in the left lung on a chest roentgenogram. After metastasis was ruled out, he underwent left upper lobectomy and mediastinal lymph node dissection. Although the preoperative diagnosis by needle biopsy was adenocarcinoma, pathological examination of the surgical specimen confirmed the diagnosis of well differentiated fetal adenocarcinoma. We performed mutation analysis of the p53, KRAS, and β-catenin genes and found a missense mutation at codon 37 of the β-catenin gene exon 3, leading to an amino acid substitution of TCT (Ser) to TGT (Cys), but no mutations were present in p53 or KRAS. Furthermore, immunohistochemical analysis detected positive staining of synaptophysin and CD 56, indicating that the tumor cells showed neuroendocrine differentiation. Conclusion. Our results suggested that a β-catenin gene alteration might be involved in the development of WDFA.
