手術を施行した耳下腺腫瘍 127 例の検討

We conducted a retrospective review of 127 cases of parotid gland tumors that were operated upon at the Toyama Red Cross Hospital Department of Otorhinolaryngology over the past 18 years. There were 108 benign tumors, and pleomorphic adenoma was the most common histological type. Surgery for deep lobe tumors required more operating time and blood loss. The tumors were malignant in 19 cases, 11 of which were parotid epithelial carcinoma, and the most common histological type was carcinoma ex pleomorphic adenoma. Surgical treatment was followed by no recurrence or metastasis in 8 of the 11 cases. In this study, there were 46 pleomorphic adenomas and 5 carcinoma ex pleomorphic adenoma, and the estimated frequency of malignant transformation of pleomorphic adenomas is 9.8%. None of the cases of noninvasive or minimally invasive carcinoma ex pleomorphic adenoma developed recurrence or metastasis, and the prognosis was good. Therefore, it is considered that histological progression is more important than the T-classification. In this study, some cases of parotid gland tumors were diagnosed as being malignant on histopathological examination even in the absence of preoperative clinical symptoms or imaging findings suspicious of malignancy, and cases of parotid epithelial carcinoma had a good local control rate and prognosis. In conclusion, surgical removal might be one of the more effective treatment options for parotid gland tumors.