Introduction:
Cutaneous indicators or manifestations are the external skin signs that might appear due to internal malignancies such as tumors. These symptoms could appear before, during, or after a cancer diagnosis. Cutaneous signs require medical attention from a physician and should not be neglected. They can occasionally be a sign of an undiscovered cancer developing within the body; this would be especially helpful if discovered before the cancer progressed to a more advanced stage. Internal cancers can show symptoms in the skin either directly as metastasis (spread of cancer from its initial site) or indirectly through syndromes created by humoral secretions developed by the tumor or can be a sign of organ compromise or occur due to unclear reasons, such as proliferative and inflammatory dermatoses. Early detection and treatment of internal cancers will be aided by promptly recognizing these skin symptoms.
What Are Curth Postulates?
Internal cancers can present with many specific and nonspecific skin symptoms. Curth proposed criteria, a well-known set of clinical criteria designed to help assess the relation between dermatological conditions and internal malignancy by finding the timing between a factor and an outcome.
The criteria are as follows:
- The onset of the neoplastic and paraneoplastic processes happened simultaneously.
- The neoplastic and paraneoplastic processes have a parallel course of skin disease and internal malignancy.
- The paraneoplastic process is linked to specific types of malignancy.
- There is no possible underlying genetic condition linked to the skin lesions.
- The general public does not frequently have these skin lesions.
- There is strong statistical support for the idea that skin disease patients are more likely to develop cancer than age- and sex-matched controls.
What Are the Cutaneous Manifestations of Internal Malignancy?
Gardner Syndrome:
Extensive adenomatous polyps in the gastrointestinal tract, particularly in the colon and rectum, are the hallmarks of Gardner syndrome. The probability of the polyps transforming malignantly is very high. The skin manifestations of Gardner syndrome include huge, malformed epidermoid cysts. There have been reported cases of osteomas affecting the skull and face's membranous bones. Mandatory yearly colonoscopy for individuals with Gardner syndrome and their family members who have not had genetic testing, starting at puberty, will help in the early detection of the condition.
Acanthosis Nigricans:
This skin disorder may manifest up to five years prior to other manifestations of the disease. The affected skin appears silky and hyperpigmented; in severe cases, it can become quite verrucous. There is a noticeable thickening of the skin in places where rubbing occurs frequently. The most common affected sites are flexural, including the neck, groin, and axillae. It is linked to gastrointestinal tract malignancies, including the liver and stomach. It may also be a sign of prostate, lung, kidney, or breast malignancies. Obese people frequently develop acanthosis nigricans. In the absence of a noticeable endocrinopathy, any nonobese adult with fast-progressing acanthosis nigricans should seriously consider the possibility of an underlying malignancy.
Bazex Syndrome:
Bazex syndrome, also called acrokeratosis paraneoplastica, is characterized by asymmetrical, scaly plaques on the body's extremities, including the toes, fingertips, elbows, knees, knuckles, heels, and ears. Dystrophic nails and keratoderma on the palms and soles may occur over time. Skin manifestations can be noted up to one year before the diagnosis of the disease. Upper respiratory and digestive tract carcinomas are the main causes of the illness. The skin abnormalities usually go away if the cancer is successfully treated, but they may return if the tumor returns.
Dermatomyositis:
An itchy rash develops into erythematous lesions and irritated voluntary muscles. Notable but less specific findings include photosensitivity, malar erythema, scalp inflammation, uneven patterns of reddish-brown skin pigmentation, and visible blood vessels that look like irregular splinters at the margin of the fingernails. From 10 to 30 percent of adult patients with dermatomyositis also have a co-occurring malignancy, which can manifest itself before, during, or following dermatomyositis diagnosis. The correlated skin and muscular illnesses usually improve if the cancer is successfully treated.
Paraneoplastic Pemphigus:
The patient may experience severe pain when this manifests as blisters on the lips, esophagus, and mouth. Lymphoma proliferative disorders, including non-Hodgkin B-cell lymphoma, chronic lymphocytic leukemia, Waldenström's macroglobulinemia, Hodgkin disease, T-cell lymphoma, Castleman's tumor, and thymoma, are among the malignancies linked to PNP. It also suggests that cancer is forming, thus identifying and treating the particular malignancy that is causing the disease.
Pityriasis Rotunda:
It is a strange skin ailment that appears spherical, scaly, hyperpigmented lesions on the proximal extremities and trunk. In 6 percent of instances, pityriasis rotunda is linked to internal malignancies; the most common neoplasms are gastric carcinoma and hepatocarcinoma.
Cowden Syndrome:
Cowden syndrome, an autosomal dominant disorder, affects women more than men. Numerous mucosal and cutaneous symptoms are possible. Trichilemmomas are flesh-colored, tiny papules mostly on the head and neck. They can resemble warts. Breast fibrocystic disease, thyroid gland tumors, ovarian cysts, lung, endometrial, and gastrointestinal polyps are examples of systemic symptoms. It has been claimed that forty to fifty percent of people with Cowden's disease have cancer.
Extramammary Paget's Disease (EMPD):
It typically affects the skin surrounding the armpit, anal, and genital areas. The most impacted are women. Clinically, several foci of EMPD are common, and the condition is marked by red, scaly plaques that do not cure. Even though it is normally painless, it can become pruritic, crusty, exudative, and ulcerate in later stages. While genital or groin EMPD may be more frequently linked to malignancies of the uterus, bladder, vagina, and prostate, perianal EMPD may be linked to colon adenocarcinoma.
Acquired Ichthyosis:
It is characterized by the formation of tiny, polygonal scales on the surfaces of the extensor and trunk muscles at any point during the cancer's progression. It is an indication of solid tumors in the bladder, breasts, or lungs, leukemias, and Hodgkin's lymphoma, among other illnesses. The underlying illness causing the skin issue must be treated to treat it.
Conclusion:
The management of cutaneous symptoms is a challenge for healthcare professionals. A correct diagnosis of such cutaneous manifestations in the body is necessary for early illness treatment and patient improvement. A skin examination can provide important early indicators alerting to underlying neoplastic activity and signs of susceptibility toward malignancy. The best possible patient treatment will be ensured by a multidisciplinary approach comprising dermatologists, oncologists, radiologists, geneticists, and other specialists.
