ABSTRACT
This multicentre study involved 28 Italian ORL Centres responding to a questionnaire sent by us which allowed recruitment of a high large number of cases of parotid neoplasms observed over a 10-year period. Statistical data obtained partly confirmed previous findings. Benign tumours account for 80% of case histories with a relationship 1:4 M/F, the most frequent being pleomorphic adenoma (57.3% of cases), followed by Warthin's tumour (32.4%), this rating not having been confirmed in case histories (8-10%) in the literature. Malignant tumours instead were fewer in number compared to the literature (14% vs 25-30%); the most frequent being mucoepidermoid carcinoma (18.2%) of which 44% G1, 33% G2 and 23% G3. Adenoid-cystic carcinoma was observed in 15.3% and < or = 10% for all the other most frequent histological malignant neoplasms. Diagnostic work-up included echotomography and fine-needle aspiration biopsy, less used imaging techniques were computed tomography, magnetic resonance imaging, Sialo-computed tomography. During this multicentre investigation more widespread use of imaging techniques has, however, been observed. The greater use of ecotomography and of fine-needle aspiration biopsy was due to simplicity of application and low cost offering good sensitivity and specificity. Surgical treatment of benign tumours consisted, in 50% of cases, in superficial paroditectomy and in approximately 30% of total paroditectomy. Enucleoresection was limited to approximately 15% of neoplasms, enucleation to <10% of cases with only 2% of pleomorph adenoma due to the well-known anatomo-pathological characteristics which may lead to relapse. For malignant neoplasms, total parotidectomy was performed in approximately 50% of cases, while in the remaining 50% an almost equal rate of superficial parotidectomy was carried out and enlarged parotidectomy, with or without sacrificing the facial nerve, which was rebuilt in 60% of cases. The lateral neck dissection most frequently carried out was of functional type in 54% and selective type in 46% with removal of levels I-III and II-IV in approximately 60% of cases. Sentinel lymph node was observed in a limited number of centres. When no clinically evident lymph nodes were present (NO) considering the tumour histotype, two thirds of patients underwent surgery or radiotherapy, while in the remainder the wait-and-see attitude was prefered. Post-operative-complementary radiotherapy was very frequently performed instead of chemotherapy. Oncological results obtained were compared with those reported in the literature: in fact for all benign neoplasms relapse ratings are about 5%, while for malignant tumours the worst prognosis was in squamous cell carcinoma with median of 37.7 on survival and metastasis rate of 16.5%. Finally, mucoepidermoid carcinoma tumours showed best survival, followed by adenoid-cystic carcinoma with ranges, respectively, 83 and 81.
