What is Subcutaneous Panniculitis-Like T-cell Lymphoma?
Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare skin cancer made up of a specific type of white blood cells called alpha-beta T-cells. It closely resembles a different condition known as panniculitis, which is an inflammation of fat tissue under the skin. In 2008, SPTCL was officially categorized separately from a more aggressive form of skin cancer called primary cutaneous gamma delta T-cell lymphoma. This was done by the World Health Organization (WHO), which classifies types of cancers and other diseases. It’s noteworthy that around 20% of people with this form of lymphoma also have autoimmune diseases, where the body mistakenly attacks its own cells. One specific condition that often needs to be ruled out when diagnosing SPTCL is lupus erythematosus panniculitis (LEP), as it shows similar clinical and cellular characteristics. In terms of what SPTCL looks like under a microscope, the cancerous white blood cells (CD8+, beta F1 expressing T-cells) are seen surrounding and breaking down fat cells. Most people with SPTCL have a good chance of recovery and a slow disease progression. However, in 15-20% of cases, a potentially serious condition called hemophagocytic syndrome (HPS) can occur. This is a disorder where the body makes too many activated immune cells.
What Causes Subcutaneous Panniculitis-Like T-cell Lymphoma?
SPTCL (Subcutaneous Panniculitis-like T-cell Lymphoma) is a type of cancer that affects certain white blood cells called T-cells. It’s linked with autoimmune diseases, where the body’s immune system attacks its own cells, in about 20% of cases. The occurrence of SPTCL is higher among patients who have lupus, a type of autoimmune disease, and vice versa.
Some researchers suggest that SPTCL and lupus might be related and could be seen to lie along the same disease spectrum. In such cases, the condition might be referred to as ‘atypical lymphocytic lobular panniculitis.’ Another possibility is that if you have one disease, you’re more likely to develop the other, or maybe one disease could be mistaken for the other.
However, we need to conduct more research to draw any solid conclusions.
Risk Factors and Frequency for Subcutaneous Panniculitis-Like T-cell Lymphoma
Subcutaneous Panniculitis-like T-cell Lymphoma (SPTCL) is a rare condition, making up less than 1% of non-Hodgkin lymphomas. It is slightly more common in females. SPTCL can affect both children and adults, with the average age of onset being 36 years.
Signs and Symptoms of Subcutaneous Panniculitis-Like T-cell Lymphoma
Patients with this condition usually have multiple raised skin patches (plaques) and small lumps (nodules) that are typically found on the legs, arms, and torso. These skin growths have a red appearance, are usually not painful, and can vary in size from half a centimeter to two centimeters. Some people may have skin patches and lumps in different stages of healing, which suggests that the condition can have periods of improvement and worsening.
Unlike with another type of skin lymphoma, these skin growths rarely develop into open sores (ulcers). Around half of the people with this condition also experience general body symptoms like fever, chills, weight loss, muscle pain, and abnormal blood tests showing liver problems. These symptoms are more common in people who also have an additional complication called hemophagocytic lymphohistiocytosis.
It’s worth noting that with this condition, people typically don’t have the disease spread to their lymph nodes or bone marrow.
Testing for Subcutaneous Panniculitis-Like T-cell Lymphoma
The disease usually only affects the layer of tissue under your skin. However, in rare cases, it can spread to your lymph nodes, blood, and bone marrow. If you have the disease, lab tests may show a high sedimentation rate or high C-reactive protein.
Cytopenias, which refers to having a lower than normal number of blood cells, increased liver function tests, and larger than normal liver and spleen could mean the disease is becoming severe and should be closely observed. To help determine the extent of the disease, a scan that uses a radioactive drug (18F-FDG) and a CT scan might be used.
This scan will detect where the drug is absorbed by your body and can help show how your body responds to treatment as well as if the disease comes back again. To confirm the presence of the disease, a small sample of tissue (a biopsy) can be taken from the affected area.
Unfortunately, doctors aren’t yet able to tell if you’re likely to get the disease based on your genes, and most patients don’t have the Epstein-Bar virus, which is a common cause for other similar conditions.
The disease can be confirmed by examining the changes in the DNA of T-cells, a type of white blood cell, in the affected area. This is usually done by a test known as a PCR or high throughput sequencing. However, similar changes can be seen in other conditions, so the result must be interpreted based on your symptoms and other test results. A study found that these changes were seen in 50% of the patients with the condition.
Treatment Options for Subcutaneous Panniculitis-Like T-cell Lymphoma
Chemotherapy, which involves using drugs to kill cancer cells, was once the standard treatment when two types of diseases, Subcutaneous Panniculitis-Like T-Cell Lymphoma (SPTCL) and primary cutaneous gamma-delta T-cell lymphoma, were believed to be the same. However, when the World Health Organization recognized these as two separate illnesses in 2008, the treatment process changed.
Unfortunately, there isn’t a one-size-fits-all treatment plan for SPTCL yet. From what research has shown, many cases of SPTCL can be effectively treated using systemic corticosteroids (a form of steroids that reduce inflammation) or immunosuppressive (medications that weaken your immune response) drugs. These drugs could include etoposide, cyclosporine A, methotrexate, chlorambucil, and bexarotene.
A classic chemotherapy drug called doxorubicin may be used if the disease progresses, i.e., gets worse over time. Additionally, radiation therapy, where high-energy particles are used to destroy cancer cells, can provide long-term remission and might help to reduce symptoms in patients with localized disease, i.e., disease that hasn’t spread to other parts of the body.
Stem cell transplants, a procedure that replaces damaged or destroyed cells with healthy cells, can be performed in cases where the disease doesn’t respond to other treatments or has spread throughout the body.
If a patient also has Hemophagocytic syndrome (HPS), a serious immune disorder, treatment options can include high-dose corticosteroids with cyclosporine A, or a stem cell transplant combined with chemotherapy.
What else can Subcutaneous Panniculitis-Like T-cell Lymphoma be?
Lupus Erythematosus (LE) is a condition that most commonly affects the face and upper limbs, whereas Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) often impacts the lower and upper limbs, and the torso. Both conditions might exhibit symptoms such as fever and swelling of the liver and spleen. Further similarities include some changes in the skin layers. However, differences can help distinguish the two. For example, LE often results in more immune cell clusters, presence of certain types of T-cells, changes at the skin-cell junction, and higher presence of other immune cells in the skin.
Aiding the diagnosis for these conditions could be the low count of specific reactive T-cells in SPTCL, and the absence of certain abnormal T-cells. A combined consideration of clinical symptoms, tissue analysis, immune response evaluation, possibly repeated biopsies, and genetic analysis could be necessary for an accurate diagnosis.
Primary Cutaneous Gamma-delta T-cell Lymphoma, on the other hand, is seen more in middle-aged adults. Its lesions may be more superficial leading to skin ulcers, with common occurrence of systemic symptoms and swelling of lymph nodes. Diagnosing this condition involves noting certain patterns in skin analysis, studying immune response of the cells, and looking for the presence of specific gene arrangements. However, this has a poor prognosis with a 5-year survival rate of just 10%.
Sometimes, even another disease named Extranodal Natural Killer/T-cell Lymphoma, Nasal type could be confused with SPTCL, yet one distinguishing feature is its positive response for the Epstein-Barr virus.
What to expect with Subcutaneous Panniculitis-Like T-cell Lymphoma
In general, the long-term outlook for most patients is very good, with 85% to 91% living for at least five years after diagnosis. However, in 15% to 20% of cases, a condition known as HPS occurs, which tends to have a poorer outlook. Additionally, recent findings suggest that involvement of the upper extremity, or upper limbs, is associated with a poorer prognosis.
Possible Complications When Diagnosed with Subcutaneous Panniculitis-Like T-cell Lymphoma
Hemophagocytic syndrome (HPS) is a condition that complicates around 20% of all cases. Unfortunately, it has a 46% survival rate over five years. Because of this, patients with HPS often need more aggressive treatments.
Statistics:
- HPS complicates about 20% of cases
- It has a 46% survival rate over a 5-year span
- Patients with HPS typically need more aggressive treatments
Preventing Subcutaneous Panniculitis-Like T-cell Lymphoma
Subcutaneous Panniculitis-Like T-cell Lymphoma is a type of cancer that affects the fatty layer beneath the skin but usually behaves well. In most cases, it can be treated successfully with certain medications such as systemic corticosteroids (drugs that reduce inflammation) or immunosuppressive agents (drugs that lower the body’s immune response).