of the parotid gland warrant consideration because of the potential for facial nerve injury occurring with surgical treatment and the risk of malignant conversion. Forty-eight cases of recurrent pleomorphic adenoma treated at the University of Michigan, Ann Arbor, between 1935 and 1975 were retrospectively analyzed. The results of surgical procedures for recurrence were determined with respect to tumor control and resultant facial nerve function. Malignant conversion developed in three (6%) of 48 cases. The results of this study underscore the importance of adequate surgical excision of initial recurrences as well as primary tumors to prevent tumor recidivism. Tumor control rates and facial nerve preservation are enhanced with formal parotidectomy for recurrent tumor when feasible. In cases in which facial nerve identification and dissection is not possible, en bloc total parotidectomy offers effective, though not absolute, control of extensive recurrence.Advances in surgical techniques -¿A-have markedly diminished the recurrence rate previously associated with surgical excision of pleomorphic adenoma of the parotid gland. Factors responsible for the recurrence of pleo¬ morphic adenoma have received extensive review over the past 50 years. While intraoperative tumor rupture and seeding, tumor multicentricity, metachronous tumor develop¬ ment, and histologie evidence of cap¬ sular penetration or hypercellularity are mentioned as factors possibly related to the development of recur¬ rence, clinical behavior of pleomor¬ phic adenomas is most closely corre¬ lated with the adequacy of surgical treatment. Rates of recurrence follow¬ ing primary surgery for pleomorphic adenoma of the parotid gland have been reported to be as high as 44%, this being attributed to inadequate surgical excision.1 Subsequent reports suggested that formal parotidectomy was associated with lower rates of recurrence than was simple excision,2 and comparisons of large groups treated within the same institution revealed a fourfold greater rate of recurrence from simple excision as compared with formal parotidectomy, whether superficial or total, with facial nerve preservation.3 Recent reports have documented that a surgi¬ cal treatment policy of formal paroti¬ dectomy for primary pleomorphic adenoma leads to recurrence rates that approach zero,46 and many sur¬ geons have adopted this policy. None¬