A rare case of extramammary Paget’s disease at the lateral canthus as a mimic of basal cell carcinoma
Introduction – Extramammary Paget’s disease
•Rare intraepithelial adenocarcinoma, typically presents in the 6-8th decades of life
•Commonly affecting apocrine-rich areas: vulva, scrotum, penis, perineum and perianal region
•Ocular EMPD is extremely rare
•Can be split into primary and secondary forms
•Primary – arises from adnexal pluripotent cells
•Secondary – epidermotropic spread from an underlying internal malignancy
•Can mimic benign skin lesions or inflammatory eyelid conditions, leading to diagnostic delay.
Case history
A male patient in his eighties presented to the oculoplastic clinic following a referral from his opticians.
Presentation:
•Crusted lesion on right lower eyelid near the lateral canthus
•Present for 2-3 years with recurrent bleeding episodes
Histopathology:
•Carcinoma in situ with pagetoid spread of highly atypical intraepidermal cells
•Immunohistochemistry: CK7+, CK20+, EMA+, CEA+, CAM 5.2+
•Neuroendocrine markers and GCDFP-15 negative
•Findings highly suggestive of secondary EMPD
Management and outcome
•Lesion excised with clear margins
•MDT recommended clinical surveillance for 3 years
•3 months: no evidence of local recurrence
Macroscopic appearance and histopathology
Fig.1: Photograph of the lesion inferior to the right lateral canthus on the right lower eyelid.
Fig.2: Histological appearance of the lesion (section stained with haematoxylin & eosin). Magnification at 5x.
Basaloid cells can be seen clearly within the lesion.
Staining
Fig.3: Staining of the lesion reveals positive expression of CEA by the lesion cells.
Fig.4: Staining of the lesion reveals positive expression of CK7 by the lesion cells.
Fig.5: Staining of the lesion reveals positive expression of EMA by the lesion cells.
Fig.6: Staining of the lesion reveals negative expression of Sox10 by the lesion cells.
Discussion
Management considerations:
•High recurrence rates due to subclinical extension and discontinuous growth – incomplete excision
•False-negative margins common
•Mohs micrographic surgery preferred to ensure complete excision
Immunohistochemistry profiles:
•Primary: CK7+, GCDFP-15+, CK20-
•Secondary: GCDFP-15+ and:
•Colorectal: CK20+, sometimes CK7+
•Urothelial: Both CK20+ and CK7+
In our case: secondary extension likely from the glands of Moll
•Negative Sox10 excludes a differential diagnosis of melanoma
Differential diagnosis
•Melanoma in situ
•Pagetoid Bowen’s disease
•Sebaceous carcinoma in situ
Careful long-term surveillance required
Early detection critical
Conclusion
•Extramammary Paget’s disease can present in the eyelid as a BCC mimic and should be fully excised with clear margins, given its propensity for recurrence.
•Immunohistochemical markers are essential for establishing a diagnosis of EMPD and stratifying it as primary or secondary, also possibly helping identify an origin in secondary EMPD.
References
1.Morris CR, Hurst EA. Extramammary Paget Disease: A Review of the Literature-Part I: History, Epidemiology, Pathogenesis, Presentation, Histopathology, and Diagnostic Work-up. Dermatol Surg. 2020 Feb;46(2):151-158.
2.Ishizuki S, Nakamura Y. Extramammary Paget's Disease: Diagnosis, Pathogenesis, and Treatment with Focus on Recent Developments. Curr Oncol. 2021 Aug 5;28(4):2969-2986.
3.Cohen MA, Hanly A, Poulos E, Goldstein GD. Extramammary Paget's disease presenting on the face. Dermatol Surg. 2004 Oct;30(10):1361-3. doi: 10.1111/j.1524-4725.2004.30412.x. PMID: 15458537.
4.Zhao M, Zhou L, Sun L et al. GATA3 is a sensitive marker for primary genital extramammary paget disease: an immunohistochemical study of 72 cases with comparison to gross cystic disease fluid protein 15. Diagn Pathol. 2017 Jul 10;12(1):51.
