The patient was a 65-year-old white woman who presented to the dermatology clinic with a nodule at the proximal interphalangeal (PIP) joint on the ring finger of her left hand. Her medical history included osteoarthritis and hypertension, both of which were well controlled on naproxen and hydrochlorothiazide, respectively. During history-taking, the patient reported trauma to the area before the nodule appeared. The lesion was more uncomfortable than painful; it did not itch or burn. The size of the lesion had stabilized six months earlier.
A 40-year-old Caucasian woman complained of a lesion on the dorsum of her left hand. The lesion did not itch, burn, or hurt. When questioned, the patient noted that the lesion had been present for years but couldn’t say for exactly how long. She had no medical problems and was not taking any medications. Cutaneous examination revealed no café-au-lait macules. The woman reported no personal or family history of genetic syndromes. When pressure was applied to the lesion, the center gave way as if a finger were pressing through a buttonhole.