Pulmonary blastoma: Report of a case

A 30-year-old woman was admitted to our hospital for investigation of an ab normal shadow in the right pulmonary hilus on a chest X-ray film, A percuta neous needle biopsy was performed, which revealed pulmonary blastoma. A rig ht upper lobectomy was performed and the pathological stage was confirmed t o be IIIa (T3N0M0). An analysis of preoperative cytological specimens showe d that epithelial tumor cells,vith thin cytoplasm were either tubular or pa pillary, while some mesenchymal tumor cells with elliptic and spindle-shape d nuclei were also found in the necrotic background. Thus, pulmonary blasto ma should be considered when a two-cell pattern consisting of both epitheli al and mesenchymal components is observed. DNA analysis was performed on pr eviously identified areas of the epithelial or sarcomatous components, usin g a microdissection method. An analysis of the p53 gene by the single-stran d conformation polymorphysm method showed an abnormal band with shifted mob ility of exon 8 in only the sarcomatous component.