Table 1.
Results of staining with enkephalin antibody
| Sample | Skin disease | PENK immunostaining |
|---|---|---|
| 1 | Granuloma annulare | Homogenously stained (+++) epidermal suprabasal keratinocytes; only occasional inflammatory cells are positive in the dermis |
| 2 | Cellular hemorrhagic cellular dermatofibroma | Heterogeneous (+), (++), or (+++) stain of epidermal keratinocytes; occasional (+) single spindle cells in the dermis |
| 3 | Squamous cell carcinoma | Heterogeneous (+) stain of malignant keratinocytes; (++) of hair follicle keratinocytes |
| 4 | Lichenoid keratosis | Homogenous (++) to (+++) stain in epidermal suprabasal keratinocytes, (+) in follicular keratinocytes |
| 5 | Seborrheic keratosis | Homogenous (++) stain in suprabasal epidermal and follicular keratinocytes |
| 6 | Psoriasis | Irregular (+++) stain in basal and (++) stain in spinous layers of keratinocytes; (+) stain in sparse inflammatory cells in the dermis |
| 7 | Psoriasis | (++) Stain in basal and spinous layers keratinocytes; (+) stain in sparse inflammatory cells in dermis |
| 8 | Intradermal melanocytic nevus | (−) Nevus cells |
| 9 | Intradermal melanocytic nevus, neurotized | Heterogeneous, predominantly (−) to (+) or occasionally (++) stain in nevus cells |
| 10 | Intradermal melanocytic nevus | (+) Nevus cells |
| 11 | Melanocytic nevus, compound lentiginous type | Heterogeneous (−) or (+) stain in nevus cells, (+++) stain in suprabasal keratinocytes |
| 12 | Intradermal melanocytic nevus | (+) Stain in nevus cells, (++) stain in epidermal keratinocytes |
| 13 | Invasive melanoma, VGP | Heterogeneous, predominantly (−) with occasional (−/+) stain in melanoma cells, (+) stain in keratinocytes in stratum spinosum and granulare |
| 14 | Melanoma in situ | (−) Stain in melanoma cells, heterogeneous (+) stain in suprabasal epidermal keratinocytes |
| 15 | Invasive melanoma, VGP | Heterogeneous, (−) to (+) stain in melanoma cells, (+) in epidermal keratinocytes |
| 16 | Nodular malignant melanoma | (−/+) Stain in melanoma cells, (++) in occasional inflammatory cells |
Abbreviation: VGP, vertical growth phase.
In all cases, staining was granular and cytoplasmic.
Immunostain: (−) negative, (+) weakly positive, (++) positive, (+++) strongly positive.