Basosquamous cell carcinoma (metatypic carcinoma, BSCC) of the dermis is a rare clinocopathologic entity which shows basaloid cell
and squamous cell carcinoma properties.
They also exhibited a dermal lymphocytic infiltrate with abundant plasma cells, which was focally present around the basaloid cell
Tubular and cribriform basal cell hyperplasia can be mistaken for adenocarcinoma, but again, the multilayered uniform basaloid cell
population is the key finding that aids in diagnostic recognition.
If fine-needle aspiration is performed, the diagnosis of PM may be made only if all major components of PM are present in the aspirate, including calcium deposition, basaloid cells
and keratinized ghost or shadow cells.
Here, we define bSCC as a tumor showing a solid pattern of growth composed of small basaloid cells
, cystic mucin, central necrosis, and typical areas of squamous differentiation, including individual cell keratinization, keratin pearl formation, and intercellular bridging; and we define BCCm as a basaloid tumor showing a more aggressive infiltrative pattern of growth, with coexistent foci of classic nodular or superficial BCC showing peripheral palisading as well as areas showing squamous features, including individual cell keratinization and intercellular bridging occurring in a continuous fashion.
The most common pattern of proliferation is that of cytologically bland basaloid cells
with peripheral palisading seen within the cellular nests.
Postoperative histopathology showed irregularly shaped masses of ghost, or shadow, cells as well as scattered basaloid cells
and numerous giant cells with areas of calcification (figure 2).
The endophytic component showed deep acanthotic growths with a periphery of mitotically active basaloid cells
and variable atypical squamous cells with frequent atypical mitoses.
It is a type of basal cell carcinoma with a histologic appearance of thin strands of basaloid cells
anastomosing with fibrotic stroma.
Histopathologically, sebaceous carcinoma is characterized by an infiltrative tumor composed of pleomorphic basaloid cells
with focal sebaceous differentiation.
The basaloid cells
are tightly cohesive, usually more prominent at the periphery of the tumor, and composed of many layers of small, monotonous cells.
Microscopically, it was a typical pilomatricoma consisting of bands of basaloid cells
maturing into ghost keratinocytes.