What is Leser-Trélat Sign?
The Leser-Trélat sign is a somewhat uncommon warning sign on the skin that cancer may be present in the body. It causes multiple harmless skin growths, known as seborrheic keratoses, to appear suddenly. No definitive measurement or guideline currently defines how this sign is diagnosed. Leser-Trélat is commonly linked to cancers like colon, breast, or stomach cancers, but it has also been connected to cancers of the kidney, liver, and pancreas. It’s not entirely clear why this happens, but some medical experts think that these growths might be caused by certain chemicals released from the cancer cells. However, this sign is often doubted due to the common occurrence of both seborrheic keratoses and cancer in older people.
Seborrheic keratoses are extremely common benign – or non-cancerous – skin growths in people over 40 years of age. They usually appear as brown, waxy spots of varying shapes and sizes. In the case of the Leser-Trélat sign, these growths are uniformly well-defined pigmented macules, spots, bumps, and patches with coloration ranging from light to dark brown or black. They often feel waxy or like velvet and look like they’re stuck onto the skin. While these spots themselves are usually easy to tell apart from other skin abnormalities, it may sometimes be necessary to examine them under a microscope for confirmation. If a doctor suspects the Leser-Trélat sign based on a physical examination, they should check for any sign of cancer in the patient. The main treatment for the Leser-Trélat sign is to treat the underlying cancer, which can resolve around half of the associated seborrheic keratoses. Any discomfort from these skin growths can be managed with itch-relieving creams or, in more aggressive cases, treatments like freezing therapy, scraping, shave removal, or using electric current to dry out the tissue.
The Leser-Trélat sign was first studied separately in the 1800s by Edmund Leser and Ulysse Trélat while exploring other skin conditions in cancer patients. A man named Hollander was the first to associate seborrheic keratoses with cancer in 1900, but the sign kept the names Leser and Trélat. By 1988, 60 documented cases of the Leser-Trélat sign had been noted.
What Causes Leser-Trélat Sign?
The Leser-Trélat sign is a warning signal of a possible hidden cancer somewhere in the body. This sign might be detected before, at the same time, or after the cancer is discovered. In some cases, patients show the Leser-Trélat sign but no cancer is found, leading to what is known as the pseudo-Leser-Trélat sign.
The sign is usually associated with various types of cancers such as:
* Cancers in the digestive system like stomach, colon, rectum, and esophagus, with stomach cancer being the most common kind.
* Breast cancer.
* Blood cell cancer or lymphoma.
* Pancreatic, Prostate, and Lung cancer.
It is also found in cancers of the Kidney, Larynx (voice box), Ovary, Uterus, Bladder, Nose and throat, Skin (Melanoma and Squamous cell carcinoma), and Liver (Hepatocellular carcinoma).
The Leser-Trélat sign isn’t exclusively tied to cancer. It can also be experienced during certain noncancerous conditions such as:
* COVID-19
* A type of leprosy called Lepromatous leprosy.
* A skin disorder called Erythrodermic pityriasis rubra pilaris.
* Infections like HIV and HPV.
Risk Factors and Frequency for Leser-Trélat Sign
The Leser-Trélat sign, a skin condition often associated with internal malignancy, typically begins around the age of 61. It is important to note that it does not favor any specific sex or race. Interestingly, when the Leser-Trélat sign is seen in individuals in their twenties, it can be a particularly strong predictor of internal malignancy. This is largely due to the fact that another skin condition, known as seborrheic keratoses, is quite rare at this age.
Signs and Symptoms of Leser-Trélat Sign
Seborrheic keratoses are common, harmless skin growths that usually appear in people over 40 years old. The look of these growths can range a lot between individuals. They can show up as well-defined spots, bumps, or plaques on the skin. Their color can vary from light shades to dark brown or black. The skin growths often feel waxy or velvet-like and look like they’re sticking to the surface of the skin. Sometimes, there can be horn-like cysts on the growths. While these growths are usually easy to tell apart from other skin conditions, a lab test might be needed if they don’t have the expected look.
When a doctor examines you they will often find many of these skin growths. They’re usually laid out in a symmetric pattern on the back that can look like a Christmas tree, a splash, or raindrops. While the back is the most common place these growths occur, they might also be found on the arms, legs, face, neck, and stomach. A common complaint is itchiness from these growths. Sometimes, these growths can be a sign of another condition related to tumors within the body. For this reason, a detailed examination and medical history is very important. These growths could appear alongside another skin condition called malignant acanthosis nigricans, which is characterized by velvety, symmetric darkening of the skin that can show up anywhere on the body in about 20% of patients who exhibit the Leser-Trélat sign, an indicator of an underlying cancer. The presence of itchiness or acanthosis nigricans broadly on the body can suggest that there might be a hidden cancer. Important things to track in the patient health record include sudden unintentional weight loss, fatigue, bloody stool, and risk factors for cancer such as smoking and family history of cancer. A sudden outbreak of uneven, uniform-looking growths in a person who previously didn’t have seborrheic keratoses should be regarded with suspicion. Unlike typical seborrheic keratoses, which develop over many years, Leser-Trélat sign lesions appear and spread rapidly, often within one year.
Curth postulates are guidelines used to determine the connection between an underlying condition related to tumors and a specific skin condition. The diagnosis of a tumor-related condition is based on meeting the following clinical criteria:
- The tumor and the related condition both started at the same time.
- Both the tumor and the related condition run a parallel course (for example, the related condition gets better when the tumor is treated and comes back if the tumor returns).
- The related condition is connected to particular types of tumor.
- The skin lesions are not linked to any potential underlying genetic syndromes.
- The skin lesions are not common in the general population.
There is a strong statistical association between having the related condition and actually having an underlying tumor. However, there has been a great deal of doubt about the Leser-Trélat sign among experts because this sign doesn’t consistently meet all of the Curth postulates.
Testing for Leser-Trélat Sign
If your doctor thinks you may have a condition known as the Leser-Trélat sign, they will likely do some checks to look for an underlying cancer. To help direct further testing, they will take a thorough medical history and perform a full physical examination. They may also order some blood tests, specifically a complete blood count (which counts the cells in your blood) and a complete metabolic panel (which measures key chemicals in your blood). Other cancer screening tests could be carried out, like mammograms (breast X-rays), Pap smears (cervical cancer tests), and prostate serum antigen tests (for prostate cancer). In some cases, they may need to take a sample of the skin lesions to confirm that they are caused by seborrheic keratoses (a type of benign growth).
These skin growths, when examined under a microscope (a process known as a biopsy), generally show the formation of new cells in the base layer of the skin and an increased number of skin cells arranged in wide columns connected together. This is typical of seborrheic keratosis lesions.
Furthermore, your doctor might use imaging tests to look for any internal cancers. The choice of imaging test will depend on what your doctor finds during the clinical assessment. They might use an X-ray of the chest, a pelvic ultrasound, or a computed tomography (CT) scan of the chest, abdomen, and pelvis. In some cases, they may recommend a CT scan of the abdomen with a contrast material (makes tissues more visible on the scan), along with an examination of your upper and lower digestive tract (endoscopies). This can be particularly important because the Leser-Trélat sign is most commonly associated with cancers in the gastrointestinal tract, such as adenocarcinoma (a type of cancer that starts in mucus-secreting glands).
Treatment Options for Leser-Trélat Sign
The best way to treat Leser-Trélat lesions, which are skin growths, is by treating the root cause, usually some form of cancer. When the cancer is treated, about half of these associated skin lesions get better. If the lesions cause symptoms, such as itching, topical creams can be used to relieve discomfort. If necessary, there are more aggressive treatments available, like freezing the lesion (cryotherapy), scraping them off (curettage), shaving off the growth (shave removal), or using electric current to destroy them (electrodesiccation). However, if the growths do not cause any discomfort, the person does not need further treatment for these skin growths beyond treating their cancer.
What else can Leser-Trélat Sign be?
There have been cases where an eruption of seborrheic keratoses (a type of harmless skin growth) has been linked with various conditions, such as:
- Severe skin inflammation
- Pregnancy
- HIV infection
- After organ transplant
Seborrheic keratoses can sometimes be mistaken for other types of skin growths, including but not limited to:
- Common warts (Verruca Vulgaris)
- Extramammary Paget’s disease (a rare skin condition)
- Acanthosis nigricans (dark patches on the skin)
- Skin tags
- Moles (nevi)
- Brown spots due to sun exposure (Solar lentigos)
- Itchy, rough skin (Lichenoid keratoses)
- Several types of skin cancer (for example, pigmented basal cell carcinoma, squamous cell carcinoma, or verrucous melanoma)
However, due to the abrupt appearance of seborrheic keratoses and their distinctive characteristics, it’s not common for them to be misdiagnosed as another skin condition. It’s also important to consider seborrheic keratoses if similar looking skin growths appear on tattoos.
What to expect with Leser-Trélat Sign
Treating the main cancer often leads to the disappearance of related seborrheic keratoses, which are non-cancerous skin growths, in about 50% of patients.
Possible Complications When Diagnosed with Leser-Trélat Sign
If found in time, treating the cancer causing the Leser-Trélat symptom (skin growths called seborrheic keratosis) can improve the patient’s chances of getting better.
Preventing Leser-Trélat Sign
People should know to talk to their doctor early if they suddenly notice new skin growths. It’s suggested to have a cancer screening if plentiful itchy brown skin spots (known as pruritic seborrheic keratoses) appear all at once. Doctors will also guide their patients that this specific type of skin growth, known as Leser-Trélat sign, will only go away in half of the cases when the underlying cancer is treated. This means that whether these growths disappear or not shouldn’t be used as a measure to decide if the cancer treatment is working.
