A 49-year-old female patient presented with a nodule in the upper lip lasting 1 year. The patient had diabetes and had a 37-year smoking history (had quit 14 months before). On clinical examination, a firm, well-circumscribed submucosal nodule measuring 0.8 cm in diameter was observed in the upper lip, left side. Because it had mobility, an excisional biopsy was performed, under the clinical hypothesis of a benign neoplasm of salivary gland. Hematoxylin and eosin staining of the specimen was compatible with a malignant neoplasm of salivary gland. Immunohistochemical analysis showed positive staining for p63, S-100, CEA, CK and Ki-67, and a diagnosis of polymorphous low-grade adenocarcinoma was established. An investigation of the anatomical region with magnetic resonance imaging did not evidence remaining lesion. The patient has been under clinical and imaging follow-up for 5 years without any sign of recurrence of the neoplasm. A 49-year-old female patient presented with a nodule in the upper lip lasting 1 year. The patient had diabetes and had a 37-year smoking history (had quit 14 months before). On clinical examination, a firm, well-circumscribed submucosal nodule measuring 0.8 cm in diameter was observed in the upper lip, left side. Because it had mobility, an excisional biopsy was performed, under the clinical hypothesis of a benign neoplasm of salivary gland. Hematoxylin and eosin staining of the specimen was compatible with a malignant neoplasm of salivary gland. Immunohistochemical analysis showed positive staining for p63, S-100, CEA, CK and Ki-67, and a diagnosis of polymorphous low-grade adenocarcinoma was established. An investigation of the anatomical region with magnetic resonance imaging did not evidence remaining lesion. The patient has been under clinical and imaging follow-up for 5 years without any sign of recurrence of the neoplasm.