Hiroyuki Tanaka1, Yutaka Akiyama1, Akiko Kitamura2, Nobuhiro Matsumoto2, Masaki Tomita3, Hiroaki Kataoka1. 1. Section of Oncopathology and Regenerative Biology, Department of Pathology, University of Miyazaki, Miyazaki, Japan. 2. Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan. 3. Department of Thoracic and Breast Surgery, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
Abstract
AIMS: We report the autopsy findings of a 58-year-old man with malignant mesothelioma in the left pleural cavity. METHODS AND RESULTS: The patient had a history of asbestos exposure, and the chest computed tomography scan on initial admission demonstrated an extrapleural sign, suggesting a nodular lesion in the chest wall. However, no nodular lesions were detectable in either of his lungs. In spite of chemotherapy, he died 4 months after the initial admission. An autopsy revealed markedly thickened pleura in a large section of the left pleural cavity without visible intrapulmonary primary tumour lesions. Histological examination of a biopsy specimen obtained prior to chemotherapy and that of an autopsy specimen showed that the pleural tumour was composed of a mixture of mesothelioma and tumour cells with squamous differentiation mimicking squamous cell carcinoma. CONCLUSIONS: To the best of our knowledge, this is the first case report of mesothelioma with extensive squamous differentiation in the English-language literature. The extensive squamous differentiation reminiscent of squamous cell carcinoma can be a pitfall in the pathological diagnosis of pleural cytology and that of biopsy specimens from patients with mesothelioma. Here, we report autopsy findings of a case of malignant mesothelioma with portions of extensive squamous differentiation, mimicking a squamous cell carcinoma.
AIMS: We report the autopsy findings of a 58-year-old man with malignant mesothelioma in the left pleural cavity. METHODS AND RESULTS: The patient had a history of asbestos exposure, and the chest computed tomography scan on initial admission demonstrated an extrapleural sign, suggesting a nodular lesion in the chest wall. However, no nodular lesions were detectable in either of his lungs. In spite of chemotherapy, he died 4 months after the initial admission. An autopsy revealed markedly thickened pleura in a large section of the left pleural cavity without visible intrapulmonary primary tumour lesions. Histological examination of a biopsy specimen obtained prior to chemotherapy and that of an autopsy specimen showed that the pleural tumour was composed of a mixture of mesothelioma and tumour cells with squamous differentiation mimicking squamous cell carcinoma. CONCLUSIONS: To the best of our knowledge, this is the first case report of mesothelioma with extensive squamous differentiation in the English-language literature. The extensive squamous differentiation reminiscent of squamous cell carcinoma can be a pitfall in the pathological diagnosis of pleural cytology and that of biopsy specimens from patients with mesothelioma. Here, we report autopsy findings of a case of malignant mesothelioma with portions of extensive squamous differentiation, mimicking a squamous cell carcinoma.