Dermoscopic findings and histopathological correlation in large cell acanthoma.

Since large cell acanthoma (LCA) has many overlapping clinical and histopathological features with other epidermal pigmented tumours, an additional method to differentiate it would be of great clinical significance. A retrospective study was performed on 33 lesions (26 patients) to identify distinct dermoscopic findings of LCA and to describe dermoscopic-histopathological correlations. The results revealed that dermoscopy significantly aids in the distinction of LCA from other epidermal tumours included in the differential diagnosis. Yellow opaque homogeneous background, brown dots, and moth-eaten border are common findings, and prominent skin markings and short white streaks are additional distinguishing features. Several important findings that are common in other diseases are rare in LCA.

Human papillomavirus genotype distribution of genital keratotic lesions.

Genital keratotic lesions include bowenoid papulosis (BP), which histologically resembles squamous cell carcinoma in situ containing high-risk HPV, condyloma acuminatum (CA) that is a genital wart containing mostly low-risk HPV, and genital seborrheic keratosis (GSK), which is a benign epidermal tumour lacking a clear etiologic relationship with HPV. This study compared HPV genotype distributions among BP, CA and GSK and revealed that BP and GSK were related to high-risk HPV whereas CA was related to low-risk HPV. It is plausible that GSK is a distinct epidermal tumour often related to high-risk HPV rather than merely a senescent form of CA considering the overall discrepancy in the frequency distribution of HPV genotypes along with histopathological differences, and the detection of high-risk HPV in GSK alerts physicians to consider more active treatment and continued follow-ups.