Skin lesions in patients with follicular lymphoma may indicate systemic disease, even in the absence of lymph node involvement. Patients should be followed closely for possible eventual lymph node involvement, a case study published in the Journal of Dermatology has shown.
Follicular lymphoma typically manifests as a B-cell lymphoma in which irregularly shaped follicles replace the normal structure of the lymph node. Although follicular lymphoma can spread beyond the lymph nodes, only a minority of cases involve extranodal disease at presentation. Further complicating the diagnosis when a patient presents with skin-related extranodal follicular disease in the absence of lymph node involvement is the need to distinguish it from primary cutaneous follicle center lymphoma (PCFCL). PCFCL is a more indolent form of lymphoma that typically requires less intensive treatment.
In this patient case, a 61-year old Asian man presented for a second opinion regarding the presence of erythematous nodules and plaques on his mid-face. The patient had initially sought medical attention for these lesions 2 years previously, and was treated with a medium-potency topical corticosteroid.
Histopathologic examination of the lesions revealed multiple lymphoid follicles with germinal center[s] in the dermis. Additional testing involving immunohistochemical staining revealed the lymphoid lesions were positive for CD10, CD20, and BCL2, and negative for CD3 and CD21, a pattern consistent with follicular lymphoma. Furthermore, fluorescence in situ hybridization (FISH) testing revealed the presence of an IGH-BCL2 gene fusion, a hallmark of follicular lymphoma. In contrast, PCFCL is not characterized by BCL2 expression.
On the basis of these results, as well as the absence of evidence of nodal or visceral involvement, stage IE follicular lymphoma was diagnosed, and the lesions were cleared following treatment with a high-potency topical corticosteroid.
Close surveillance over the course of the following year revealed a left axillary swelling on CT scan that subsequent histopathological examination determined to be a composite of follicular lymphoma and Hodgkin lymphoma. Given the presence of localized Hodgkin disease, as well as follicular lymphoma characterized by a low tumor burden, the patient was treated with a short course of combination chemotherapy with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) plus local radiation therapy.
“As we regarded the patient as having a systemic disease and followed him up carefully, nodal involvement was detected and diagnosed without delay. It is very important to distinguish between PCFCL and skin lesions of follicular lymphoma because they are different in prognosis,” the authors concluded.
Takahashi-Shishido N, Morimura S, Tomita Y, et al. Case of follicular lymphoma presenting with nodules and plaques on the face [published online April 24, 2019]. J Dermatol. doi: 10.1111/1346-8138.14890