Textbook of Advanced Histopathology and Cutaneous Diseases

• Acanthosis — A histopathological alteration consisting of the thickening of the prickle cell layer (stratum spinosum) of the epidermis, caused by the proliferation of malpighian cells. In a clinical macroscopic sense, the term is frequently associated with 'Acanthosis nigricans', a skin condition characterized by hyperpigmented, velvety, and rough plaques, predominantly localized in intertriginous areas (neck, axillae, groin), serving as an important cutaneous marker for insulin resistance, obesity, or endocrine disorders.