UPMC Dermatopathology "Case of the Month" Presentations
UPP - Department of Dermatology, Dermatopathology Unit
Case Authors: Peggy Lin MD, Michael Y. Zhang MD PhD, Drazen Jukic MD PhD<
MAY 2004 CASE OF THE MONTH
DISCUSSION & DIAGNOSIS
DIAGNOSIS
Final Diagnosis: Acantholytic squamous cell carcinoma
DISCUSSION
Epidemiology: Lesions of acantholytic (adenoid) squamous cell carcinoma (ASCC) usually occur on sun-exposed skin, especially on face and ears. Often macroscopically, they appear as nodular, scaled, crusted, and ulcerated lesions. Since this description also fits non-acantholytic SCCs, definite diagnosis is determined with dermatopathology. Although most ASCCs occur on sun exposed skin, they have been reported to occur in non-sun exposed areas, such as the breast 1 and oral mucosa 2. Most patients have been reported to be between 50 to 70 years of age3, with males being affected more than women.
Histology: Tumors are composed of dyskeratotic squamous cells that exhibit acantholysis in lobular formation. Tumor cells are polygonal, with glassy eosinophilic cytoplasm, and focal squamous pearl formation6,7. Cells arrange in invasive, tubular, pseudoglandular, and even pseudovascular configurations. Adenoid structures are usually one cell thick. Dyskeratotic and acantholytic cells arrange singly or as groups within the lumen7.
Differential diagnosis: Includes sweat gland carcinomas5,6, in which true glandular cells (not keratin producing squamous cells) compose the single row of cuboidal cells lining the lumina. Sweat gland carcinomas usually stain for CEA, S-100 protein, and amylase. Sweat glands also produce sialomucin5, in contrast to the hyaluronic acid (mucin) produced by ASCCs. Adenoid basal cell carcinoma is also on the differential, but usually these tumors show more of a fibromyxoid stroma than ASCC. ASCCs may be confused with vascular tumors (angiosarcomas) 6,8. Therefore, indicators of endothelial differentiation may be used in conjunction with cytokeratin stains to decipher between these two etiologies. Endothelial markers include factor VIII-related antigen, blood group antigen, and Ulex europaeus.
Treatment: The treatment for ASCC is surgical excision. This patient also received a split thickness skin graft.
Prognosis:
This tumor is reported to be more aggressive than the non-acantholytic counterpart3.
In one case series4, it recurred in 7 of 10 patients. Rates of metastasis range
from 2%5 to 19%6. Poor prognosis was associated with tumors over 1.5 cm in size
6 and in one series, 10 of 49 patients developed subsequent visceral malignancies6.
REFERENCES
1. Watanabe K, Mukawa A, Saito K,
et al. Adenoid squamous cell carcinoma of the skin overlying the right breast.
Acta Pathol Jpn. 1986; 36(21):1921-9.
2. Jones AC, Freedman PD, Kerpel SM. Oral adenoid squamous cell carcinoma: a
report of three cases and review of the literature. J Oral Maxillofac Surg.
1993; 51: 676-81.
3. Petter G, Haustein U. Histologic subtyping and malignancy assessment of cutaneous
squamous cell carcinoma. Dermatol Surg. 2000; 26: 521-30.
4. Banks ER, Cooper PH. Adenosquamous carcinoma of the skin: a report of 10
cases. J Cutan Pathol. 1991; 18: 227-34.
5. Johnson WC, Helwig EB. Adenoid squamous cell carcinoma (Adenoacanthoma).
Cancer. 1966, Nov; 19(11): 1639-50.
6. Nappi O, Pettinato G, Wick MR. Adenoid (acantholytic) squamous cell carcinoma
of the skin. J Cutan Pathol. 1989; 16: 114-21.
7. Bernstein SC, Lim KK, Brodland DG, Heidelberg KA. The many faces of squamous
cell carcinoma. Dermatol Surg. 1996; 22: 243-54.
8. Nappi O, Wick MR, Pettinato G, et al. Pseudovascular adenoid squamous cell
carcinoma of the skin. Am J of Surg Pathol. 1992; 16(5):429-38.
