Residency Program - Case of the Month

Clinical History

The patient is a 76-year-old male with a history of diabetes mellitus and bullous pemphigoid.  He presented with diffused erythema, edema and slight fissuring in both palms without active blisters.  CBC analysis revealed a marked lymphocytosis with predominantly mature lymphocytes (WBC: 37.8 K/MM3 , Lymphocytes: 31.8 K/MM3).
Flow cytometry  of the peripheral blood was performed and showed markedly elevated CD4:8 ratio (32:1).   This CD4+ population was negative for CD25-, CD26-, CD30-, and showed  aberrant T-cell antigen drop out (subset CD7-).  There was no evidence of monotypic B-cell population and no blasts.

Pathologic Findings

Sections of the punch biopsy taken from the right palm are shown below.

Click on image to enlarge.

Figure 1 Right palm (biopsy site shown as A) with diffused erythema, edema and slight fissuring

Figure 2 Right palm. Dermal lymphoid infiltrate with epidermotropism. H&E 40x

Figure 3 Right palm. A closer view at the atypical lympoid infiltrate with epidermotropism. H&E 200x

What is most likely the diagnosis?

Choose one answer and submit.