Classification Of Melanocytic Tumors Research Articles

Update on classification of melanocytic tumors and the role of immunohistochemistry and molecular techniques.

The nine pathways to melanoma outlined in the most recent WHO classification of skin tumors attempt to capture the typical evolution of different subtypes of melanoma as governed by cell of origin, mutagenic factors and oncogenic drivers. This pathway-based classification will continue to be refined as we learn more about melanocytic tumor biology. I review the practical application of immunohistochemistry and molecular techniques in the diagnosis of melanocytic tumors in the context of this classification.

Molecular testing for melanocytic tumors: a practical update.

The work-up of melanocytic tumors has undergone significant changes in the last years following the exponential growth of molecular assays. For the practicing pathologist it is often difficult to sort through the myriad of different tests available currently for clinical use. The molecular tests used in melanocytic pathology can be broadly divided into 4 categories: (i) Tests useful in the differential diagnosis of nevus versus melanoma (primarily used as an aid in the diagnosis of histologically ambiguous melanocytic tumors), (ii) Tests that predict prognosis in melanoma, (iii) Tests useful in the classification of melanocytic tumors and (iv) Tests that predict response to systemic therapy in melanoma. This review will present an updated overview of major ancillary tests used in clinical practice.

New techniques in dermatopathology that help to diagnose and prognosticate melanoma

Routine light microscopy supplemented with immunohistochemistry in cases of metastatic or spindle cell melanoma are standards of care for the diagnosis and staging of melanoma. Not all melanocytic tumors can be confidently classified as melanoma or benign nevus by histology, however. In addition, tumor thickness and ulceration, the current American Joint Classification on Cancer prognosticators for primary cutaneous (stages I and II) melanoma used in clinical practice, do not perfectly predict an individual's clinical course. Recent advances in molecular techniques and bioinformatics mandate testing and use of novel methods for the detection, diagnosis, and classification of melanocytic tumors that can accurately predict tumor behavior and help in selecting the most optimal and individualized therapy.