Interactive Case Study - November 2026

Tender, Expanding Pink Plaque on the Left Cheek

Arjun Pandya, MD

Tammie C. Ferringer, MD

Andrew Desrosiers, MD

An 87-year-old male with a past medical history of chronic lymphocytic leukemia presented with a rapidly growing painful plaque on the left pre-auricular cheek. This was previously biopsied and read as a squamous cell carcinoma 10 months prior; however, the patient was lost to follow up. Following his return, he subsequently had a Mohs debulk biopsy of this lesion.

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Figure 1 left preauricular cheek - 3.6cm irregular, scaly violaceous plaque with central atrophy at site of previous biopsy

Figure 2: H&E 10x initial biopsy, prior to Mohs debulk

Figure 3: H&E 1.2x Mohs debulk

Figure 4: H&E 4x Mohs debulk, superficial dermis

Figure 5: H&E 10x Mohs debulk, superficial dermis

Figure 6: H&E 10x Mohs debulk, deep dermis

Figure 7: H&E 20x Mohs debulk, deep dermis

1. Which of the following is the best diagnosis?

Metastatic Adenocarcinoma

Microcystic Adnexal Carcinoma

Squamoid Eccrine Ductal Carcinoma

Squamous Cell Carcinoma

Syringomatous Carcinoma

2. What is the most common mutation in this tumor?

CDKN2A

GNAQ

NRAS

PTCH1

TP53

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Acknowledgements

The authors thank Dr. Jacqueline Junkins-Hopkins, MD for their thoughtful review and editorial suggestions to help improve this manuscript.

Author Profiles

Arjun Pandya, MD

Geisinger

Arjun Pandya is PGYIV dermatology resident at Geisinger Health Systems in Danville, Pennsylvania. A native of Youngstown, Ohio, he earned his BS in combined sciences at Youngstown State University and MD at Northeast Ohio Medical University through the accelerated medical program. Arjun is a member of Alpha Omega Alpha Medical Honors society. His interests include complex medical dermatology, dermatopathology, and cutaneous t-cell lymphomas.

Tammie C. Ferringer, MD

Geisinger

Dr. Ferringer is the section leader for GML's dermatopathology subspecialty section. She is also an associate in the Department of Dermatology at Geisinger Medical Center and serves as the director of the Dermatopathology Fellowship Program. She earned her M.D. at Medical College of Pennsylvania in Philadelphia and completed her residency in dermatology at Geisinger. Dr. Ferringer completed a fellowship in dermatopathology at the Medical University of South Carolina in Charleston.

Andrew Desrosiers, MD

Skin Care Physicians of GA

Dr. Andrew Desrosiers is a Mohs surgery fellow based in Macon, GA, with subspecialty training in dermatopathology. He completed his medical education at the University of Mississippi School of Medicine in 2020 and continued his postgraduate training at Geisinger Health System, where he completed a transitional year internship, dermatology residency, dermatopathology fellowship.

Question:

Interactive Case Study - November 2026

Acknowledgements

Author Profiles

Tender, Expanding Pink Plaque on the Left Cheek

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