Hyperplastic sublingual gland in association with a congenitally missing ipsilateral submandibular gland

A congenitally absent unilateral submandibular gland is a rare condition. We present such a case with an associated ipsilateral benign hyperplastic sublingual gland. The enlarged sublingual gland may well represent a compensatory response to the missing submandibular gland, but it is known that sublingual gland tumours are malignant in approximately 90% of cases and so a sublingual gland swelling is viewed with a high degree of suspicion. Clinical diagnosis of sublingual hyperplasia becomes a challenge if there is a missing unilateral submandibular gland, but a full investigation is important to rule out a more sinister pathology.