A 17-year-old male adolescent presented with a painless, gradually enlarging lesion overlying the upper part of his sternum. The lesion, which did not move with swallowing, had been present since birth. Physical examination revealed a round, well-circumscribed, soft, fluctuant, nontender swelling, 5 cm in diameter, just below the sternal notch (Figure 1). An ultrasound scan showed a cystic swelling containing mobile debris that appeared to be confined to the subcutaneous tissues.
Co Chay Lay E, Motley R, Laidler P. Cystic Swelling Overlying the Upper Sternum in a Teenager—Quiz Case. Arch Dermatol. 2006;142(9):1221-1226. doi:10.1001/archderm.142.9.1221-c