What Are Mycosis Fungoides and Sézary Syndrome? Symptoms, Causes, Diagnosis, Treatment, and Prevention
Both mycosis fungoides and Sézary syndrome fall under the umbrella of cutaneous T-cell lymphomas (CTCL), a category of non-Hodgkin lymphomas that greatly impact the skin (cutaneous refers to the skin). In short, they are both types of cancer.
It’s important to note, though, that these diseases are not skin cancer. The affected skin cells themselves are not cancerous. Instead, cancer develops in the white blood cells known as T lymphocytes, or T cells, which regulate the immune system and help the body stave off infections. These malignant T cells travel from the blood to the skin tissue, accumulating in the skin and forming patches, plaques, or tumor nodules. (1,2) With Sézary syndrome (also called Sézary’s lymphoma), however, the malignant T cells (called Sézary cells) are also found in the lymph nodes and blood. (3)
Sézary syndrome is still not well understood, but it’s thought to be a more advanced or aggressive form of mycosis fungoides (thus categorized as stage 4 of mycosis fungoides). But it also may be a different illness altogether. (4,5) Either way, Sézary syndrome is the more fast-moving cancer of the two cutaneous T-cell lymphomas. (3) And mycosis fungoides (also called Alibert-Bazin syndrome or granuloma fungoides) is slow-moving and develops over several years. (6)
Mycosis fungoides can often mimic the appearance of other common skin conditions, such as eczema and psoriasis, which can spur misdiagnoses. Mycosis fungoides can surface anywhere on the skin, but it most commonly affects areas shielded from sun exposure, such as the buttocks and inner parts of the arms and thighs.
Individuals with mycosis fungoides are likely to experience the following symptoms:
Like mycosis fungoides, Sézary syndrome can take on the appearance of skin conditions, such as eczema, and generally appears on areas of the body that are not exposed to the sun. Sézary syndrome is more aggressive than mycosis fungoides and as such brings about additional symptoms, which can include:
The cause of mycosis fungoides and Sézary syndrome has yet to be determined, but known risk factors include:
Other causation theories include retroviruses, such as human T-cell lymphotropic viruses, and exposure to carcinogenic (cancer-causing) substances. (8)
Usually, a diagnosis of mycosis fungoides or Sézary syndrome is made by a dermatologist. In order to make that diagnosis, he or she will likely utilize the following tests and procedures:
At the time of diagnosis, your healthcare team will also learn what stage your disease is in. Mycosis fungoides progresses slowly through several stages, but not all people impacted by mycosis fungoides progress through all of the stages. (6)
Stage 1 The itchy, scaly, red rash (in patches or plaques) either appears on less than 10 percent of the body (stage 1A) or more than 10 percent (stage 1B), generally in areas not exposed to the sun, such as the lower abdomen, upper thighs, buttocks, and breasts. The rash can come and go for months or even years. It’s often difficult to diagnose at this stage, since the disease often resembles other skin disorders, like psoriasis. (5,6)
Stage 2 At this point, any amount of the skin surface can be covered with patches or plaques, and the lymph nodes have become enlarged but are not cancerous (stage 2A). Also under the category of stage 2: The presence of any tumors (1 centimeter or larger) on the skin with noncancerous lymph node involvement (stage 2B). (5)
Stage 3 Nearly the entire surface of the skin is reddened. Patches, plaques, or tumors are likely present. Lymph nodes may be enlarged, but still cancer-free. Abnormal lymphocytes may be detected in the blood, but they are not cancerous. During this stage, individuals may experience necrosis, when cells in the lower skin layers die. (5, 8)
Stage 4 The progression to stage 4 means that the majority of the skin is red. Any amount of patches, plaques, or tumors are present, along with one of the following:
During stage 4, mycosis fungoides may spread throughout the body to other organs. The liver and spleen may become enlarged. At times, the heart muscle may be affected as well. Individuals often experience high temperatures, weight loss, anemia, and symptoms of malaise and weakness, too. Gastrointestinal symptoms (and possible ulcerations of the intestines), coughing, and difficulty swallowing may develop. If the brain is affected, eye pain and vision issues may occur. (8)
Because Sézary syndrome is defined by the presence of malignant T cells in the lymph nodes and blood, this disease is also considered stage 4 mycosis fungoides. (5)
The prognosis for those with mycosis fungoides varies depending on a number of factors, including how slowly or rapidly the disease is progressing. In any case, both mycosis fungoides and Sézary syndrome are difficult to cure. Because of this, the treatment goal is often to relieve symptoms (palliative care) and to improve quality of life, not to completely eradicate the disease. It’s not unusual for individuals to live normal lives for several years while in the midst of treatment. (2)
It’s estimated that 65 to 85 percent of individuals with mycosis fungoides have early stage 1A or 1B disease. And the majority of those with early-stage mycosis fungoides never progress to a more advanced-stage of the disease, according to a report. (12) In addition, the same study noted that those with stage 1A disease have an almost unchanged life expectancy compared with those who never had cancer.
But individuals who have an advanced-stage disease (stages 2B, 3, or 4A) that includes tumors, erythroderma (Sézary syndrome), or lymph node or blood involvement have a survival rate of about two to five years. (12) Those with advanced-stage mycosis fungoides or Sézary syndrome may want to consider stem cell therapy, such as allogeneic hematopoietic stem cell transplantation (SCT), which has yielded positive results, with some achieving long-term remissions, according to a report. (13)
Before moving forward with a treatment plan, your healthcare team will assess your general health, your age, and the stage of your disease. For instance, those with early-stage mycosis fungoides or Sézary syndrome may respond very well to therapies directed at skin. But those with more advanced disease may need skin-directed therapies along with systemic therapies, meaning treatments that affect the entire body. Here are some options:
Treatment often begins here and it’s often effective for years. Options include:
These are often used alone or in combination with one another. They are also given along with skin-directed therapies.
Mycosis fungoides and Sézary Syndrome both require conventional medical treatments. That said, a variety of complementary and alternative therapies can be a successful part of an overall treatment plan, notably reducing stress. Any alternative or CAM approaches should be okayed by your healthcare team first. Some to consider, include: (11)
In addition, it’s important for those with mycosis fungoides and Sézary syndrome to keep skin moisturized, since dry, cracked skin can amplify itch and make skin more vulnerable to infection. To protect the skin, individuals should:
Not everyone with mycosis fungoides or Sézary syndrome experiences complications, but it’s important to know what to look out for, including:
Skin Infections It’s not unusual for those with mycosis fungoides or Sézary syndrome to have cracked skin, which can lead to bacterial skin infections and viral herpes skin infections. Signs of infection may include redness, swelling, increased pain, or weeping fluid. (14)
Second Primary Cancer Those with mycosis fungoides (especially women) are at increased risk for a second primary malignancy, including non-Hodgkin lymphoma; Hodgkin lymphoma; melanoma; and lung, female breast, prostate, colon, and renal cancers, according to research. (15) Secondary cancers usually occur during the first year of diagnosis, noted one study. (16)
Nervous System Involvement Central nervous system (CNS) involvement is very rare, but can include confusion, slowed thinking, lethargy, blurred vision, blindness, eye pain, and swelling of the optic nerve. These complications typically occur three to five years after the initial diagnosis, per research. (17)
All cutaneous T-cell lymphomas are rare, accounting for just 7 percent of all non-Hodgkin lymphoma cases. But of those cancers, mycosis fungoides and Sézary syndrome are the most common types. (18)
There are about 3,000 new cases of mycosis fungoides confirmed in the United States each year. (11)
While Sézary syndrome is the second most common form of cutaneous T-cell lymphoma after mycosis fungoides, its exact prevalence is unknown. (19)
Mycosis fungoides is often thought of as a disease of middle-aged white men, but all ethnicities can be impacted. In fact, more Black Americans are diagnosed with mycosis fungoides annually than white Americans — and with more advanced disease and worse survival outcomes, according to a study. (20)
There are likely a diverse set of reasons for this disparity, including access to information, insurance coverage, occupational exposures, and also a lack of education among dermatologists regarding mycosis fungoides presentations on skin of color. (20)
While white patients with mycosis fungoides tend to experience red, eczema-like patches, Black patients and dark-skinned Latinos often have scaly, ring-shaped white spots that are thin and depressed in the center, notes Maritza Perez, MD, professor of dermatology at UConn Health in Farmington, Connecticut. Because of this presentation, mycosis fungoides is frequently misdiagnosed in darker skinned individuals as atopic dermatitis, tinea versicolor, and vitiligo, according to a report. (20)
Beyond differing presentation, age likely factors into many misdiagnoses, as well. “Mycosis fungoides in Black people tends to occur in one’s forties, as opposed to their fifties like Caucasians. Because of this, dermatologists are likely less inclined to suspect cutaneous T-cell lymphomas in Black patients,” says Dr. Perez. “To diagnose this condition in Black patients at an earlier stage, there needs to be a high level of suspicion and you’ll likely need to see a dermatologist with experience in immunology.”
Both mycosis fungoides and Sézary syndrome are types of non-Hodgkin lymphomas, which are blood cancers that develop in the lymphatic system from cells called lymphocytes. (Lymphocytes are a type of white blood cell that fights infections.) In all, there are more than 90 types of non-Hodgkin lymphoma (NHL), including:
Some rarer types of NHL include:
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