Skin disease can be a sign of internal cancer
There is a rising trend in the occurrence of internal cancers and some skin manifestations reflect them, so this trend made me think of writing an article about it, not only to educate young dermatologists but the general public as well.
Sometimes, skin disease may be the only presenting complaint of many internal disorders or malignancies. It can look like a skin rash that has spread beyond the confines of the area where the original skin manifestation appeared, for example, metastasis of cancer, or direct tumor extension.
Paraneoplastic Syndromes are a group of rare disorders that occur when the immune system has a reaction to a cancerous tumor. Usually, no tumor cells are found within the skin, since it is only a reaction of the immune system that causes it and not a metastasis.
Internal organ tumors may secrete a variety of inflammatory, proliferative, and metabolic factors that lead to such skin changes or rashes. Up to 20% of cancer patients may experience this. Skin manifestations may develop even before the diagnosis of malignancy is determined, thus aiding in its early identification and intervention.
Carcinoid syndrome occurs when a rare, cancerous tumor called a carcinoid tumor secretes certain chemicals into one’s bloodstream, causing a variety of signs and symptoms and Gardner’s syndrome—a rare, inherited condition where people develop hundreds and sometimes thousands of abnormal growths (polyps) in their large and small intestines.
Internal cancer indicates its existence by various skin conditions, so close observation and a suspicious mind are required for the detection of cancer. A rash may precede, occur concurrently, or may follow after the occurrence of cancer. Any patient with unusual skin conditions who does not respond to therapy should be thoroughly investigated for underlying immunosuppression, including cancer. Prompt identification of these skin conditions will help in early diagnosis and treatment.
There are so many other skin diseases that provide a challenge to the clinician. A proper diagnosis of such disease manifestations is essential to treat the diseases early for the benefit of the patients.
Skin lesions occurring as a result of internal cancer are called “dermadromes of internal malignancy.” Internal cancers metastasizing to the skin are rare. Such metastasis usually occurs after the fifth decade. In our study, cutaneous metastasis was observed in 12% of patients. In a study by Browstein et al., the most common malignancy producing cutaneous metastasis was lung carcinoma, followed by carcinoma colon in males and breast carcinoma in females. The most frequent cutaneous infection encountered was herpes zoster, in contrast to the study conducted by Kiliç et al., which reported fungal infections to be the most common. The occurrence of herpes zoster in patients in remission may indicate a recurrence of malignancy. There is an increased incidence of infections in patients with internal malignancies, which may be attributed to an immunocompromised status of the patient due to the disease or chemotherapy. According to our study, middle-aged (ages 40 to 60) people were most commonly affected. Drug reaction was observed to be the most common chemotherapy-induced skin condition, whereas Kanti et al. reported hair loss to be the common condition due to chemotherapeutic agents. Pruritus (severe itching) was found to be associated with lymphoma and is seen only in later stages of the disease.
As per the study by Hassan et al., 2.4% of patients presented with ichthyosis (very dry, scaly skin that resembles the scales of a fish), but a study in India resulted in 8% presenting with ichthyosis.
Radiation dermatitis was found in three of 68 patients on radiotherapy. It may take weeks to months for the occurrence of skin manifestations following the completion of radiotherapy.
Cutaneous vasculitis (when your immune system hurts your blood vessels by mistake, producing purplish–red spots, usually found on the legs) was observed in two patients.
One patient with renal-cell carcinoma had a necrotizing ulcer and another patient with gastric carcinoma had very itchy lesions on both lower limbs. Blood-related cancers like leukemia and lymphoma are commonly associated with cutaneous vasculitis but other manifestations are scabies, pus in the skin, neck discoloration and skin thickening, leg swelling due to the buildup of lymph fluid in the body, and fluid-filled cysts that form in children, often on the head and neck.
There are five criteria called Curths postulates that establish a connection between a skin disease and cancer from internal organs: 1) The skin disease and internal cancer occur at the same time; 2) Both conditions follow a parallel course; that is, if the skin rash gets worse, the cancer also worsens. If the skin is improving, so is the cancer; 3) Some cancers are associated with rare skin disorders like abnormal hair growth of the lanugo newborn type, often confined to the skin of the face and neck, although other areas also may be involved. A 66-year-old woman with metastatic breast cancer developed growth of fine, lanugo-type hair on her face and progressive growth of eyebrow and eyelash hairs.
Xanthomas are lesions on the skin containing cholesterol and fats, which can occur in patients with leukemia, lymphoma, and multiple myeloma, a type of bone-marrow cancer.
Sixty percent of stomach adenocarcinoma cases develop thickening and hyperpigmentation of the neck, armpit, and inguinal areas (singit), as well as the mouth and hands.
Another example is the abrupt appearance of many wartlike growths in the body, called Leser Trelat, which in younger individuals may be a warning sign for stomach and colon cancer.
There are also genetic links between skin diseases and internal cancers, like neurofibromatosis, which refers to three different conditions involving the development of tumors that may affect the brain, spinal cord, and the nerves that send signals between the brain, spinal cord, and all other parts of the body.
Peutz-Jegher’s Syndrome is a rare disorder in which growths called polyps form in the intestines. A person with PJS has a high risk of developing certain cancers. Manifestations include brownish or bluish-gray spots on the lips, gums, inner lining of the mouth, and skin; clubbed fingers or toes; cramping pain in the belly area; dark freckles on and around the lips of a child; blood in the stool that can sometimes be seen with the naked eye; and vomiting.
There are so many other skin diseases that provide a challenge to the clinician. A proper diagnosis of such disease manifestations is essential to treat the diseases early for the benefit of the patients.
