A young woman developed an unusual adenocarcinoma in each submandibular salivary gland at an interval of 30 months. This presentation has not been described previously. The possible etiology for this and treatment options are discussed. The choice of diagnostic imaging (ultrasound versus magnetic resonance imaging) is highlighted. As a result of regular follow-ups using diagnostic ultrasound, a second tumor was observed to reach a dimension of 8 mm in less than 6 months. This is probably the first report documenting the extent of initial growth of this rare tumor.