[Clinicopathologic study on the mode and degree of invasion of the trachea by thyroid carcinoma]

Among 23 patients with thyroid carcinoma infiltrating to the trachea, total 7 laryngectomy and 16 tracheal resection were carried out, associated with thyroidectomy and neck dissection. The infiltrating mode and degree to the trachea in these patients were classified into 2 types according to the anatomical characteristics: Types of cartilage and membranous portions. Moreover, the former was further subclassified into 3 divisions. The subtype I of cartilage portion: Infiltration to the adventitia of trachea. Histologically, there were 3 well differentiated carcinoma, 3 poorly differentiated carcinoma and one medullary carcinoma. The prognosis was favorable comparing to other types. All 7 patients are alive. The subtype II or III of cartilage portion: Infiltration to the cartilage or annular ligament of trachea. Poorly differentiated carcinoma were noted in 6 of 7 patients. Five are alive and 2 died. The membranous type: Infiltration to the membranous portion of trachea. Esophageal invasion was noted in 7 patients. Undifferentiated carcinomas and squamous cell carcinoma took over a half of the patients. Two are alive and 7 died. The prognosis was the worst.