Diagnosis: Pilomatricoma/Pilomatrixoma, histopathology
Case submitted by dermRounds Dermatology Network to the dermRounds community.
Clinical photograph(s) submitted for peer review and discussion.
Submitted by dermRounds Dermatology Network. Originally posted June 27, 2008.
See case discussion.
• Epidermal inclusion cyst • Dermoid cyst • Pilomatrical carcinoma • Calcified lymph node • Foreign body granuloma • Basal cell carcinoma
• Also known as calcifying epithelioma of Malherbe • Most common in children and young adults — solitary, firm, deep-seated nodule • "Tent sign": stretching overlying skin reveals multifaceted surface • Histology: basophilic cells (viable) transitioning to shadow/ghost cells (anucleate) — pathognomonic • Calcification and ossification common • Beta-catenin (CTNNB1) mutation — same pathway as Gardner syndrome • Multiple pilomatricomas: consider Gardner syndrome (APC mutation) or myotonic dystrophy • Pilomatrical carcinoma is the rare malignant counterpart
Tags: pilomatricoma, pilomatrixoma, histopathology, dermrounds dermatology network