Keratoacanthoma

Keratoacanthoma

Robert P. Blereau, MD
Volume 47 - Issue 12 - December 2007

An 89-year-old man reported that this lesion began developing on his left forearm 11 days earlier. It is a keratoacanthoma, a rapidly growing but benign neoplasm that occurs predominantly on the extensor surfaces of the hands and forearms of white men over age 50. Because it is grossly indistinguishable from squamous cell carcinoma, microscopic diagnosis is mandatory.

Spontaneous regression occurs but may leave a disfiguring scar. Surgical excision (as was done in this case) or electrodessication and curettage is recommended.

References

1. Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 4th ed. Philadelphia: Mosby; 2004; 711.
2. Hodak E, Jones RE, Ackerman AB. Solitary keratoacanthoma is a squamous-cell carcinoma: three examples with metastases. Am J Dermatopathol. 1993;15: 332-342
3. LeBoit PE. Is keratoacanthoma a variant of squamous cell carcinoma? New insights into an old controversy ... soon? Am J Dermatopathol. 1995;17:319-320.
4. Putti TC, Teh M, Lee YS. Biological behavior of keratoacanthoma and squamous cell carcinoma: telomerase activity and COX-2 as potential markers. Mod Pathol. 2004;17:468-475.