Salivary Duct Cyst: Histo-pathologic Correlation
A 63-year-old male patient, presented with a swelling in front of the left ear that had persisted for 4 months. The swelling initially small had gradually increased in size. No associated symptoms were present. On extra-oral examination [], a single, well-defined, localized, oval shaped swelling was present in the left preauricular region, measuring approximately 3 × 4 cm in size. On palpation, it was non-tender, mobile, fluctuant, and soft in consistency anteriorly and firm posteriorly. It was compressible but not reducible. Skin over the swelling was pinchable. A posteroanterior mandibular radiographic image revealed no abnormal findings. Ultrasonography of the left preauricular region [] revealed a well-defined anechoic area measuring 3.3 × 1.9 × 3 cm seen in the superficial part of the left parotid gland. Fine needle aspiration yielded a clear straw colored fluid, which had a protein content of 4.6 g/dl. Magnetic resonance imaging (MRI), following aspiration, revealed a well-defined cystic lesion seen in the superficial part of the left parotid gland on T1 and T2 weighted sequences measuring 3.5 × 2.0 × 3.2 cm. []. A hypointense lesion with a focus of hyperintensity within the lesion was seen in T1-weighted image []. A similar focus of hypointensity was seen within the lesion in gradient and T2-weighted images []. This indicated that there was hemorrhage within the lesion, which could have been caused by the aspiration. T2 weighted sequence with fat saturation and short tau inversion recovery (STIR) images revealed an area of high signal intensity within the left parotid gland. The cyst was enucleated under general anesthesia. Histopathological investigation revealed a cyst wall lined with oncocytes []. There were occasional lymphoid follicles and normal salivary gland tissue in the surrounding connective tissue. These features were consistent with the diagnosis of a salivary duct cyst. Patient was reviewed after 6 months and there was no evidence of recurrence [].