Metastasizing keratoacanthomas? The difficulties in differentiating keratoacanthomas from squamous cell carcinomas

Area of Science:

• Dermatology
• Pathology
• Oncology

Background:

• Keratoacanthoma and squamous cell carcinoma share diagnostic challenges.
• Accurate differentiation is crucial for appropriate patient management.
• Histopathological evaluation can be difficult, leading to potential misdiagnosis.

Purpose of the Study:

• To review the diagnostic difficulties between keratoacanthoma and squamous cell carcinoma.
• To present illustrative patient cases highlighting diagnostic challenges.
• To emphasize the clinical implications of accurate diagnosis and treatment.

Main Methods:

• Review of diagnostic criteria for keratoacanthoma and squamous cell carcinoma.
• Presentation of 13 patient cases with differential diagnostic considerations.
• Analysis of histopathological findings and clinical outcomes.

Main Results:

• Difficulties in differentiating keratoacanthoma from squamous cell carcinoma were illustrated.
• A recommended diagnostic phrase for uncertain cases is provided: "probable keratoacanthoma, but squamous cell carcinoma cannot be ruled out."
• Potential for recurrence or metastasis of inadequately treated keratoacanthoma as squamous cell carcinoma was highlighted.

Conclusions:

• Even experienced pathologists may misdiagnose keratoacanthoma.
• Inadequate treatment of misdiagnosed keratoacanthoma can lead to adverse outcomes.
• Clinicians should treat most keratoacanthomas with adequate removal and close follow-up.