Salivary gland cancer in Southern Brazil: a prognostic study of 107 cases / Cáncer de glándula salival en el sur de Brasil: un estudio pronóstico de 107 casos

ABSTRACT

Background: Salivary gland cancers (SGC) represent an uncommon group of heterogeneous tumors. We per-formed a retrospective survey of SGC diagnosed in a reference center for treatment of malignant tumors from thesouth of Brazil aiming to determine the prognostic value of demographic, clinic and pathologic features.Material and Methods: Cases diagnosed as SGC between 2006 and 2016 were retrospectively collected. Medicalrecords were examined to extract demographic, clinic, pathologic and follow-up information.Results: One-hundred and seven cases of SGC were identified. The most common SGC were mucoepidermoidcarcinoma (MEC) (n = 39) followed by adenoid cystic carcinoma (AdCC) (n = 29). Among AdCCs, 55.2% of caseswere classified as cribriform, 27.6% as tubular and 17.2% as solid. The tubular subtype had the highest percentageof cases with perineural invasion (p=0.01). Among MEC, 61.5% of cases were classified as low grade, 15.4% asintermediate grade and 19.9% as high grade. Low grade MEC had the lowest percentage of cases with perineuralinvasion (p=0.04). The 5-year survival for loco-regional control, disease-free survival (DFS) and disease-specificsurvival were 75%, 70% and 84%, respectively. The following features were associated with poor DFS advanced age (p=0.03), rural residency (p=0.01), being a smoker or former smoker (p=0.01), pain (p=0.03), nodal metastasis(p<0.001), need for chemotherapy (p=0.02), neck dissection (p=0.04), perineural invasion (p=0.01), and being diag-nosed with AdCC compared to MEC (p=0.02).Conclusions: The clinco-demographic and pathologic features identified as prognostic factors reveal the profile ofpatients at increased risk of recurrence and who would benefit from closer follow-up.(AU)