[Diagnosis and treatment of rare malignant tumors in external auditory canal].

OBJECTIVE: To analyze the diagnosis, therapy and prognosis of the rare cases of malignant tumors in external auditory canal.

METHOD: Eight cases of rare malignant tumors in external auditory canal were collected except squamous cell carcinoma and adenoid cystic carcinoma. The clinical manifestation, staging, surgical method, secondary treatment and prognosis were analysed.

RESULT: There were 5 cases of basal cell carcinoma and 2 cases of mucoepidermoid carcinoma and 1 case of myoepithelial carcinoma. Three cases of the 5 basal cell carcinoma in external auditory canal have been misdiagnosed for a long time. After admission, 4 of the 5 basal cell carcinoma were T1 stage and cured only by a complete resection of tumor. One case of T2 stage basal cell carcinoma was found recurrence 2 years later after the first excision of tumor, and was treated with radiotherapy. Tumor was controlled. Two cases of mucoepidermoid carcinoma had been misdiagnosed as a benign tumor and received a resection. One case was found metastasis to the parapharyngeal space and nasopharynx and was treated with concurrent chemotherapy. Tumor was also controlled after 5-years follow-up. Another case was found metastasis to parotid gland and received an expanding tumor resection. No recurrence was detected after a 1-year followed up. One case of T4 stage myoepithelial carcinoma in external auditory canal was a metastasis of parotid and received a partial temporal bone resection. No-recurrence was found 1 year later.

CONCLUSION: Because the tumors above have a very low incidence in external ear canal and the location of tumors are hidden, they are often misdiagnosed and delayed in treatment. Therefore, otologists should pay more attention to avoid the misdiagnosis. To the treatment, complete surgical resection of early-stage tumor is important and for late-stage tumor, a supplemented by chemoradiotherapy may be needed.