Postoperative Radiotherapy with Extensive Fields to Treat Lymphoepithelial Carcinoma of Major Salivary Glands: A Prospective Single Institute Analysis of 32 Patients

Abstract

(1) To evaluate the role of extensive-field postoperative radiotherapy treating lymphoepithelial carcinoma of major salivary glands (2) To identify patterns of failure and important clinical/pathologic prognostic factors for optimal treatment of lymphoepithelial carcinoma. Clinical data of 32 patients with pathologically confirmed primary lymphoepithelial carcinoma of salivary gland and excluding of nasopharyngeal carcinoma by MRI and nasopharyngoscope examination, treated in the Fudan University from 2005 to 2009, was examined and enter this study. The 2002 AJCC staging for major salivary glands carcinomas was used to retrospectively stage these patients. The prescription doses of postoperative radiotherapy ranged from 6000 cGy to 6600 cGy. A forward-planned multisegment 3DCRT technique was used which can spare the contra lateral salivary glands, eyes, spinal cord and brainstem. All treatment plans were normalized to achieve 95% volume coverage of the target by the prescription dose. The target volume include the operative bed and ipsilateral level Ib, II and III cervical lymph nodes for N0 patients, Ia nodes were not routinely irradiated except for the submandibular glands cases. Ipsilateral whole neck was treated for any N+ patients. The survival analysis was performed using Kaplan-Meier curves. All these analysis were calculated on the platform of SPSS software version 13th. The median age at presentation was 46.5 years. The median follow-up was 15.3 months. Twenty-one males and 11 females accounted for 21% stage I, 37% stage II, 24% stage III, and 18% stage IV disease. Three patients (9.4%) had positive surgical margins or residual lesion and 8 (25%) had cervical lymph node involvement. Locoregional recurrence occurred in 2 patients, one was in the primary site, and another one developed recurrence outside the treatment field. A total of 4 distant metastases were found, including 1 bone, 1 lung, 1 both and 1 nasal cavity. Among of them, the patient with lung metastasis died during this follow-up. The 2-year survival rate was 82.2% for all the patients. The 2-year disease free survival rate was 87.5%. The extensive-field postoperative radiotherapy provided an exciting local control outcome for lymphoepithelial carcinoma of major salivary glands. A relative high frequency of distant metastasis may indicate the potential of chemotherapy.