Gantz M, et al. - This paper re-analyzed the characterization of the population, morphology, associations, and disease course of extensive or atypical eruptions of Grover disease. Patients affected by extensive or atypical Grover disease displayed greater variability than among those with typical disease. Malignancy appeared as a common association. Moreover, immunosuppression possibly played a role in the pathogenesis of extensive or atypical Grover disease.