Acanthosis palmaris or acquired pachydermatoglyphia, commonly known as tripe palms, is a rare cutaneous paraneoplastic syndrome. It presents as rugose thickening of the palms, which leads to an exaggeration or distortion of the dermatoglyphic ridges and sulci (resembling cooked bovine tripe or intestines).

Tripe palms most often affects elderly adults, particularly those with underlying malignancies (which are present in over 90% of all cases). The most commonly associated malignancies are gastric and pulmonary carcinomas; other malignancies including those of the esophagus, rectum, biliary tract, thyroid, uterus, liver, kidneys, lymph nodes, pancreas, bronchus, and breast have also been reported.

Skin changes typically arise prior to the cancer diagnosis but may be seen at any point during the clinical course. Tripe palms typically features progressive hyperpigmentation and hyperkeratosis of the skin, predominantly on the palmar surface of the hands and fingers, leading to a thickened and velvety appearance. It often presents concurrently with acanthosis nigricans (in approximately 77% of cases), and there may be overlap in cutaneous changes.

Although its pathogenesis is not well understood, tripe palms is hypothesized to be related to the oversecretion of circulating tumor-derived growth factors, particularly transforming growth factor-α (TGF-α). The proposed mechanism entails increased epidermal cell proliferation arising from cytokine-mediated signaling downstream of various growth factor receptors.

Nonmalignancy associated disorders include interstitial lung disease, bullous pemphigoid, systemic mastocytosis, psoriasis, and exfoliative dermatitis.