Approach to dermal-based lymphoid infiltrates and proliferations

Area of Science:

• Dermatopathology
• Hematopathology
• Immunohistochemistry

Background:

• Dermal lymphoid infiltrates present diagnostic challenges due to overlapping features.
• Differential diagnosis includes reactive processes, pseudolymphomas, and cutaneous lymphoid neoplasms.
• No single test is sufficient for definitive diagnosis.

Purpose of the Study:

• To advocate a systematic histopathological approach for diagnosing dermal lymphoid infiltrates.
• To highlight key features for distinguishing benign from malignant lymphoid proliferations.
• To emphasize a multiparameter diagnostic strategy.

Main Methods:

• Review of histopathological and immunophenotypic features of dermal lymphoid infiltrates.
• Advocacy for a stepped diagnostic approach based on lymphocytic composition and cytomorphology.
• Integration of clinical, histopathological, immunophenotypic, and molecular data.

Main Results:

• A stepped approach utilizing B- vs. T-cell ratio and cell size is proposed.
• Considering the relative incidence of cutaneous involvement aids diagnosis.
• A multiparameter approach is essential for accurate diagnosis.

Conclusions:

• A structured histopathological strategy improves the diagnosis of dermal lymphoid infiltrates.
• Lymphocyte composition and morphology are crucial initial diagnostic elements.
• Comprehensive integration of all available data ensures accurate distinction between reactive and neoplastic processes.