Article previously published in the Cutaneous Lymphoma Foundation's Forum Fall 2013 newsletter.
Primary cutaneous T-cell lymphomas (CTCL) are very rare in children, teens and adolescents compared with adults aged over 50 years. Mycosis fungoides (MF) is the most frequently diagnosed primary cutaneous lymphoma in childhood other than lymphomatoid papulosis. However, due to its uncommon manifestation in young patients, the diagnosis of CTCL is often delayed or missed. This is further complicated by the fact that MF may clinically simulate benign rashes, in particular atopic dermatitis, eczema or vitiligo. One of the most common misdiagnosis is “ringworm”.
A few studies have described the clinical and pathological aspects of MF in children and adolescents. Investigators found that most young patients presented with white or very light-colored, so-called “hypopigmented” patches on the skin. When these patches were biopsied and stained for certain lymphocyte (white blood cell) markers, the initial manifestation of MF was characterized by the presence of CD8+ T-cell phenotype, unlike the CD4+ T- cell phenotype usually encountered in MF. Of note, most young patients were found to have early stage disease without spread into blood, lymph nodes or organs.
None of the published studies have been large enough to assess prognosis and outcome in childhood. However, data from retrospective studies suggest that the outcome of CTCL in childhood seems rather better compared to adults when monitored over a median time period of 9 years. Very rarely, children have flare-ups. These data are in line with our experience at our centers and the recent findings researched by Dr. Guitart’s team at Northwestern University who followed more than 100 children with MF. They found that most children and teenagers with MF had limited patch disease involving less than 10% of the skin. Most importantly, they found that young patients rarely (3 patients out of 76) developed skin tumor lesions and none progressed into lymph glands, organs or blood.
Lymphomatoid papulosis (LyP) in children is also very rare; the features of LyP are similar to adults and characterized by crops of self healing, itchy or burning skin lesions. Lesions contain unusual cells that are similar to those found in certain types of lymphomas, but the disease is considered non-cancerous. Like in adults, children have a risk to develop a “true” lymphoma, but otherwise the prognosis is excellent. When patients with LyP develop lymphomas, they remain mostly localized to the skin and rarely spread to lymph glands. A relatively common finding in children with CTCL is the overlap of MF with LyP. For this risk patients need to be regularly seen by their doctor to pick up any changes that may signal early lymphoma.
The cause of CTCL is not known. No lifestyle factors have been definitely linked to childhood CTCL. Neither parents nor children have control over factors that may cause CTCL. Children, who have had Hodgkin lymphoma, may carry a slightly higher risk of developing CTCL, but this is quite rare.
Unfortunately, there are no specific guidelines for treatment of CTCL in children. The treatment choices should be influenced by their long-term risks and side-effects. In general, skin-directed therapies such as phototherapy with narrowband-UVB light, intermittent use of topical steroids, topical retinoids, topical nitrogen mustard and/or tacrolimus (calcineurin inhibitors as used in atopic dermatitis/eczema) may be indicated. These therapies are the cornerstones to control recurrent rashes and relief of itch in mycosis fungoides. Rarely, in severe cases systemic therapies are needed. Quick showers/bathing with mild unscented soaps and emollients are important to control skin dryness, minimize infections and also important to restore the skin barrier. Bubble baths are not recommended as they can increase itching. Similar to atopic dermatitis/eczema there is little dispute that the presence of bacteria on the skin such as Staphylococcus aureus is common in mycosis fungoides and can worsen skin disease. Dilute bleach baths as directed by your doctor help to minimize the risk for germ spreading and infection.
Every young patient should be evaluated by a team or team member specializing in CTCL with the expectation that he or she will return to a normal life focused on family, friends, and the future.
Christiane Querfeld, MD, PhD, Dermatologist and Dermatopathologist, Memorial Sloan Kettering Cancer Center, New York
Joan Guitart, MD, Professor in Dermatology and Pathology, Northwestern University, Chicago