Cutaneous follicle center lymphoma: A clinicopathologic study of 19 cases

Cutaneous follicle center lymphoma (FCL) is reported to have a unique immun ophenotype and clinical course as compared with nodal FCL. We studied 19 ca ses of FCL of the skin using paraffin embedded tissue. An immunohistochemis try panel included CD45, CD3, CD20, CD43, CD21, bcl-2, bcl-6, CD5, and CD10 . Molecular studies were performed by polymerase chain reaction for immunog lobulin heavy chain (IgH) and t(14;18). Trisomy 3 was performed by fluoresc ent in situ hybridization (FISH) in 13 cases. Follow up was obtained in 17 cases (range 3 to 137 months). Patients included 10 females and 9 males ran ging in age from 33 to 88 years at first presentation (mean, 64). Twelve of 19 presented in the head and neck and 6 in the trunk and 1 on the arm. All had no known lymph node disease at presentation. Seventeen patients had no nodal disease with a minimum 3 month follow-up; 2/19 had unknown lymph nod e status with no follow-up. All cases were immunoreactive with CD20 and neg ative with CD3. Bcl-2 was immunoreactive in 11/18 cases, bcl-6 in 15/15, CD 10 in 14/17, CD43 in 2/16 (both were CD10 immunoreactive) and CD5 in 1/15 ( it was also bcl-6 immunoreactive). Eight of 18 cases were monoclonal for Ig H. Three of 17 showed the presence of t(14;18). FISH was positive in 4 case s for trisomy 3 ranging from 16 to 22% (12% threshold). Follow-up showed no evidence of disease in 14/17 patients (4 to 137 mos). 3/17 patients are al ive with disease (17 to 100 mo), and no patients died of disease.