Ung thư biểu mô tế bào vảy phát triển trong trung thất: Những khó khăn trong xác định nguồn gốc khối u và chẩn đoán - báo cáo trường hợp lâm sàng

Abstract

The differential diagnosis of basal mediastinal tumors is based on their anatomy and origin. In the classification of the World Health Organization (WHO) 2015, update 2021, basically, mediastinal tumors are divided into 3 groups: Anterior group, mediastinum group and posterior group. In terms of origin, detailed classification has many different types of mediastinal tumors, but they are classified into 3 large groups: (1) Tumors of the thymus; (2) Germ cell tumours of the mediastinum; (3) Haematolymphoid tumours of the mediastinum. The location of the appearance of tumors belongs to groups that can be specialized or intertwined interstitial (eg: Thymoma is usually found only in the anterior mediastinum; germ cell tumors may be present in multiple sites).        Squamous cell epithelium is an anatomical component present in many different organs in the body. Therefore, squamous cell carcinomas (SCC) can also occur in many places, but primary SCC in the mediastinum is rare. In the WHO classification of mediastinal tumor, the only SCC is present in the thymic carcinoma classification.        We present a rather special case with an SCC tumor located in the mediastinum (not related to the thymus), the diagnosis is difficult. The patient underwent laparoscopic biopsy of the tumor, and the diagnosis of SCC was confirmed by histopathology and immunohistochemistry, but the origin of the tumor was still controversial. The expert opinion suggested that the tumor may originate from pleural mesothelial cells with squamous metaplasia, and eventually turn into squamous cell carcinoma and this case can be considered as a case of Primary Squamous Cell Carcinoma of Pleura (PSCCP), an extremely rare case. We are looking forward to receiving feedback from the teachers, teachers and colleagues after reporting this case.