Deeper cuts are the best stain

Case 849  18.9.13 (H Diwan)  F 44 labial mass 

Hidradenoma papilliferum.  Superficial biopsy showing tubulo-glandular dermal nests.  Point is made that superficial biopsy may miss the deeper, diagnostic papillary architecture of this tumour. 

DD: Tubular apocrine adenoma – this is usually found in scalp/axillae. 

Case 917  24.12.13  (M. Hurt)  M 34 2 day history of tender nodule on digit 

Lymphomatous pattern of inflammation, but inclusion (Guarnieri) bodies high in follicular epithelium confirm molluscum contagiosum 

Quoting Rapini: "The very best special stain in dermatopathology is deeper levels sectioned through the block!" 

Case 949  11.2.14 (M. Hurt)  F 71 Generalised pink papules (*teaching) 

Scabies: wide range of suggestions, some ridiculous relating to porokeratosis which this doesn’t resemble histologically or clinically.  Parakeratotic areas, with underlying rather lupus-like pattern of inflammation eosinophils sparse.  Diagnosis confirmed by step-sectioning.  “The best stain is deeper sectioning” 

Case 2182  19.10.18  (R. Carr)  M 55 middle finger 

Digital papillary adenocarcinoma: superficial part arising from epidermis looks like poroma or spiradenoma.  Cystic structure underneath doesn’t show the usual papillary projections very much. Lining of cyst shows a rather glomus-like double layer of cells.  The deeper more malignant areas show dual myoepithelial and epithelial differentiation.  P63+ve, helps to distinguish this from poroma, hidradenoma and metastatic adenocarcinoma. 

Case 2611   9.7.20 (S. Taibjee) F 86 thigh (*teaching)  

Scabies: mite demonstrated on deeper levels