Anaplastic lymphoma kinase (ALK1) immunohistochemistry in diagnostic dermatopathology; an update

Immunohistochemistry in Dermatopathology and its Relevance in Clinical Practice

Immunohistochemistry (IHC) is an important diagnostic tool in histopathology. Dermatopathology is a rapidly developing subspecialty of histopathology. Although IHC is not widely used in routine dermatopathology practice, its application is gradually increasing. IHC is used to differentiate two conditions with similar morphology, to confirm a diagnosis as well as to assess prognosis. It is more commonly used for neoplastic conditions like melanocytic, hematolymphoid, and spindle cell tumors, although uses can be very wide. Although IHC can aid in diagnosis, sometimes interpretation can be difficult as there may be overlapping findings. Thus, IHC should not be interpreted in isolation and should be done in the context of clinical and histological findings. In this review, we have discussed the uses of various immunohistochemical markers in dermatopathology in the light of current literature and their clinical relevance.

Immunohistochemistry in dermatopathology

CONTEXT

Immunohistochemistry is not a diagnostic test but a highly valuable tool that requires interpretation within a context.

OBJECTIVE

To review the current status and limitations of immunohistochemistry in dermatopathology.

DATA SOURCES

English-language literature published between 1980 and 2014.

CONCLUSIONS

Although immunohistochemistry is rarely completely specific or sensitive, it is an important adjunctive technique in dermatopathology and can be helpful in a series of diagnostic dilemmas.