Discussion
Primary cutaneous CD4+ small to medium T-cell lymphoproliferative disorder is a sporadic disease that typically affects individuals aged 50-70, though it can also occur during childhood and even infancy (3, 7, 9). The typical lesion is an asymptomatic, rapidly growing, solitary nodule or plaque in the face, neck, or upper extremities (1, 7, 10, 11). Our patient’s age, the shape of the lesion, and the area of involvement were compatible with previous studies. The greater prevalence of this disease in the elderly and also its greater presentation on sun-exposed areas can raise the suspicion of the effective role of sun exposure as a risk factor for this disease. Out histological findings were compatible with the literature, where most publications described the infiltration of CD4+, small to medium-sized T-cells in the dermis, with some infiltration of B-cells, plasma cells, and histiocytes (1, 10).
Most cases need surgical or medical interventions to be cured, but there are two case reports of spontaneous complete remissions. A case was also reported to regress three months after a local biopsy (10-12). For patients with localized lesions, surgical excision, intralesional steroids, or radiotherapy is recommended. Some studies revealed the effective role of cyclophosphamide or interferon-alpha for multiple or generalized skin involvement (4, 6-8, 13). Even though there are multiple choices for treatment, most studies consider surgical excision as the best choice for solitary lesions due to desirable outcomes, minimal complications, inexpensiveness, and rare recurrences. In our study, an excisional biopsy with a safety margin of 0.5 mm taken under local anesthesia yielded an excellent outcome.
In the literature, recurrence has been reported in 4.26% of cases. Most individuals showed no recurrence during 10-26 months of follow-up. A rare local recurrence was reported in the second month of follow-up in a patient who underwent local excision. In another patient, the progression of multiple cutaneous lesions was reported despite systemic chemotherapy and local excision (7, 12). Like most documented cases, no signs and symptoms of relapse were detected in our patient after two months of follow-up.
Patients with CD4+ small to medium-sized T-cell lymphoproliferative disorder rarely progress toward malignancies in the course of the disease. Recurrence and generalized involvement are also scarce. Even though novel studies have shown the uncertain potential of malignancy of the disease and indicated an excellent prognosis, many studies have reported a five-year survival rate of approximately 60-80% (1, 2, 7, 10, 13). The incompatibility between disease prognosis and five-year survival may be due to the use of the previous classification of disease (cutaneous CD4+ small to medium pleomorphic T-cell lymphoma) in most publications. This incompatibility may be resolved using updated criteria of classification.
The very low prevalence of CD4+ small to medium-sized T-cell lymphoproliferative disorder has greatly reduced its clinical suspicion, such that it may be overlooked in the list of differential diagnoses for rapidly growing lesions. It is important to remember that although the lesions appear abruptly and grow rapidly, they are not malignant and can be cured with simple, cheap, non- invasive treatments. Here, we reported this disease as a rare subtype of cutaneous T-cell lymphomas in a 50-year-old man to remind all physicians to keep this entity in mind and avoid unnecessary aggressive interventions.