In a public hospital in Lima, Peru, 24 patients with 16 types of paraneoplastic dermatoses were identified by data collection. The most frequent dermatosis was dermatomyositis (four patients). The other dermatoses were malignant acanthosis nigricans, palmoplantar keratoderma, bullous dermatoses, lymphomatoid papulosis, edematous scarring vasculitic panniculitis, Norwegian scabies, primary systemic amyloidosis, necrolytic migratory erythema, infective dermatitis, pancreatic panniculitis, generalized pruritus, Lesser-Trelat syndrome, and acquired ichthyosis. Most of these paraneoplastic dermatoses were diagnosed before (45.8%) or at the time of (38.5%) the diagnosis of the underlying malignancy. The most frequent underlying malignancies were lymphoma, adenocarcinomas of the upper digestive tract, and malignant neoplasms of the pancreas. The average age of the patients was 47.0 ± 16.9 years and the length of the disease since diagnosis was 13.7 months. The mortality rate was 75%. Paraneoplastic dermatoses are rare dermatologic entities that are difficult to diagnose. Surveillance is also hampered when patients do not have easy access to health care centers due to financial and geographical issues. However, when identified, they might facilitate the early diagnosis of an associated tumor and contribute to increase the surveillance of patients. © 2010 by Anais Brasileiros de Dermatologia.