There are many skin conditions that may occur which are associated with cancers, as well as some benign tumors, inside the human body.
Cutaneous conditions associated with internal benign tumors and/or malignancies:
Erythema gyratum repens Lung cancer
Hypertrichosis lanuginosa acquisita Lung cancer
Paraneoplastic pemphigus Non-Hodgkin lymphoma
Chronic lymphocytic leukemia
Castleman’s disease
Sarcoma
Thymoma
Tripe palms Lung cancer
Tripe palms with acanthosis nigricans Stomach cancer
Pityriasis rotunda Hepatocellular carcinoma
Migratory thrombophlebitis Pancreatic adenocarcinoma
Acanthosis palmaris Bronchial carcinoma
Sign of Leser–Trélat Gastrointestinal adenocarcinoma
Acquired ichthyosis Hodgkin disease
Pityriasis rotunda Hepatocellular carcinoma
Paraneoplastic pigmentation Small cell bronchial carcinoma
Acrokeratosis paraneoplastica Squamous cell carcinoma of the upper respiratory or gastrointestinal
tracts
Necrolytic migratory erythema
Glucagon secreting pancreatic islet cell adenoma
Dermatomyositis Lung cancer in men, breast and gynaecological tumors in women and colorectal cancers in both sexes
Scleroderma‐like skin changes Carcinoid syndrome
Paraneoplastic pemphigus B‐cell proliferations and thymoma or thymoma‐like neoplasms; specifically Non Hodgkin’s lymphoma.
Dermatitis herpetiformis Lymphoma
Porphyria cutanea tarda and variegate porphyrias Hepatocellular Carcinoma
Erythroderma and exfoliative dermatitis Mycosis fungoides or Sézary syndrome
Pyoderma gangrenosum Hematological malignancy
Sweet syndrome
Hematological malignancy