Fibroepithelioma of Pinkus

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Basal cell carcinoma (BCC) is the most common human cancer with diverse histopathological subtypes.
• Fibroepithelioma of Pinkus (FEP) is considered a rare BCC variant, exhibiting distinct clinical and morphological traits.
• Understanding FEP's incidence and characteristics is crucial for accurate diagnosis and patient management.

Purpose of the Study:

• To determine the incidence of Fibroepithelioma of Pinkus (FEP) among all diagnosed Basal Cell Carcinomas (BCCs).
• To evaluate the clinical and pathological characteristics of patients diagnosed with FEP.
• To discuss the differential diagnosis and biological behavior of FEP in relation to other BCC subtypes and trichoblastoma.

Main Methods:

• Retrospective analysis of four primary FEP cases.
• Evaluation of patient demographics, tumor topography, and lesion dimensions.
• Histopathological examination to assess cellular atypia, mitotic activity, and stromal characteristics.

Main Results:

• FEP prevalence was found to be 0.7% of all BCCs.
• The four analyzed FEP cases (3 females, 1 male, mean age 53.4 years) showed indolent behavior with no significant atypia or solar dermatosis signs.
• Lesions were small (mean horizontal diameter 7.7 mm, vertical 2.8 mm), completely removed (pT1), and typically presented as 'pure' FEP, with one case showing mixed features with nodular BCC.

Conclusions:

• Fibroepithelioma of Pinkus (FEP) is a rare BCC variant with a low incidence (0.7%) and indolent clinical behavior.
• FEP exhibits distinct histopathological features, including basaloid cell cords within a loose fibrous stroma, and lacks significant atypia or mitotic activity.
• The overlapping characteristics of FEP with trichoblastoma highlight the importance of careful differential diagnosis for predicting the biological behavior of cutaneous tumors.