Conservative parotidectomy for the treatment of parotid cancers

A conservative parotidectomy is defined as any procedure that is less than a classic superficial parotidectomy, and where less than a full facial nerve is dissected. The aim of this study was to evaluate the oncologic effects of a conservative parotidectomy in a series of patients with malignant tumors of the parotid gland.

The medical records of 43 patients treated at Severance Hospital from 1992 to 2002 who had been diagnosed with parotid cancers confined to the superficial lobe, and had also undergone conservative parotidectomies were reviewed. There were 16 males and 27 females, ranging in age from 8 to 84 years. Sixteen tumors (37%) were high-grade and 27 tumors (63%) were low-grade cancers. Twenty-four patients underwent neck dissection simultaneously with the primary lesion. Surgical treatment was followed by radiotherapy in 10 patients. The follow-up period ranged from 8 to 130 months, with a mean duration of time at 57.7 months.

The overall survival rate and the disease-free rate at five years were 88% and 79%, respectively. Univariate analyses showed histologic tumor grade (p = 0.003) and pathologic neck node metastasis (p < 0.001) to be significant variables. Based on multivariate analysis, only the presence of pathologically positive lymph nodes proved to be significant (p = 0.001). Occult metastases rates was 25% (3 of 12 cases) for high-grade tumors and none of the low-grade tumors had microscopic metastases. Recurrences developed in eight cases (19%). Four cases (9%) had a local or locoregional failure. Of these cases, two cases were high-grade tumors (13%, 2 of 16) and the other two cases were low-grade tumors (7%, 2 of 27). The six cases (14%) of which four cases were high-grade (25%) and two cases were low-grade (7%) had positive surgical margin but showed no evidence of local recurrence after additional postoperative radiotherapy. The incidence of postoperative facial nerve paralysis (HB > 1) was 12% (5 outof 43) for a temporary deficit, but there was no permanent paralysis.

Conservative parotidectomy with appropriate postoperative radiotherapy may be an acceptable procedure without potential morbidity, such as postoperative facial palsy, in the treatment of low-grade parotid cancers confined to the superficial lobe if the facial nerve is sufficiently distant from the tumor.