Pulmonary pleomorphic carcinoma arising in mixed squamous and glandular papilloma: A case report

The tumor was composed of fibrovascular cores and papillomatous fronds lined by pseudostratified glandular epithelium. A lesion covered with keratinizing squamous epithelium was also observed. In addition, the solid part beneath the mild atypical squamous epithelia was composed of malignant-appearing squamous cells and spindle-shaped atypical cells. Therefore, we interpreted that pleomorphic carcinoma (squamous cell carcinoma and spindle cell carcinoma) arose in mixed papilloma. AbstractSolitary pulmonary papillomas (SPPs) are rare lung neoplasms. Histologically, SPP is classified into three subtypes, and mixed squamous and glandular papilloma (MP) is the rarest subtype. Although SPPs are considered benign tumors, there have been several reports on the synchronous malignant transformation in SPPs. An 82-year-old asymptomatic man was referred to our hospital for further examination of a 2.2  cm-sized left lung tumor. Pathology of bronchoscopic specimens showed the possibility of pulmonary papilloma but did not reveal any malignancy. The patient complained of bloody sputum during the eighth month after the initial visit. The size of the lesion had increased to 4.3 cm. These data sug gested the existence of malignancy, and the patient underwent an operation. Histologically, the tumor was composed of fibrovascular cores and papillomatous fronds lined by pseudostratified columnar cells and mucin-filled goblet cells. Keratinizing squamous epithelium was also observed. Overall, ...
Source: Thoracic Cancer - Category: Cancer & Oncology Authors: Tags: CASE REPORT Source Type: research