title: Pleomorphic carcinoma of the lung associated with loss of heterozygosity of p53 gene.
abstract: We report a case with pleomorphic carcinoma of the lung in a 70-year-old man. Pleomorphic carcinoma is characterized by a heterogenous composition that includes epithelial and mesechymal malignancies. In the present case, the tumor was composed of a mixture of unequivocal squamous cell carcinoma and spindle cell components resembling sarcomatous overgrowth. The spindle component did not include a heterologous mesenchymal element characterized by overt differentiation for bone, cartilage, neuron or muscle tissue. To evaluate a state of differentiation of the spindle cell component, we immunohistochemically examined expression of the antigens including vimentin, cytokeratin, sarcomeric actin, alpha-smooth muscle actin, S-100 protein, CD34, Factor VIII, and CD68. The results showed sole expression of vimentin in the spindle cell component, suggesting an immature state of the mesenchymal lineage. Furthermore, the spindle cell component of this case was genetically characterized by loss of heterozygosity (LOH) at a codon 234 of exon 7 of the p53 gene. This mutation causes an amino-acid replacement (Tyr to Cys), which was previously proven to attenuate p53 function. The present case may suggest a relation between somatic alteration of the p53 gene and histogenesis of pleomorphic carcinoma.
authors.affiliation: Department of Pathology, Ehime University School of Medicine, Shigenobu, Ehime, Japan.
authors.forename: Norimasa
authors.initials: N
authors.lastname: Arita
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Mikami
authors.forename: Minako
authors.initials: M
authors.lastname: Yoshida
authors.forename: Ichiro
authors.initials: I
authors.lastname: Konishi
authors.forename: Norio
authors.initials: N
authors.lastname: Horiike
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Miyauchi
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Miyazaki
authors.forename: Masato
authors.initials: M
authors.lastname: Nose
authors.forename: Masao
authors.initials: M
authors.lastname: Ono
mesh_terms: D000368:Aged; D001706:Biopsy; D006579:Heterozygote; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology*; D008297:Male; D015898:Tomography Scanners, X-Ray Computed; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: D016159:Tumor Suppressor Protein p53