Acquired pachydermatoglyphy. A cutaneous sign of internal malignancy.

A 70-year-old man with hypertrophic osteoartropathy secondary to a squamous cell carcinoma of the lung presented a distinctive pattern of late-onset bilateral palmar keratoderma. A yellowish rugose appearance with accentuation of normal ridges and sulci (pachydermatoglyphy) involving the palms was observed. The differential diagnosis and the clinical relevance of acquired pachydermatoglyphy as a cutaneous marker of internal malignancy are discussed.