Primary cutaneous follicle center cell lymphoma and limited stage follicular non-Hodgkin's lymphoma: A comparison of clinical and biological features

Primary cutaneous follicular lymphoma (PCFL) and nodal follicular lymphoma (NFL) are different entities, which, nevertheless, exhibit common features. The aim of this study was to compare the clinico-biological characteristics and the outcome of patients with PCFL and with limited stage NFL. A group of 22 consecutive patients with PCFL presenting with single or multiple cutaneous lesions was compared to a group of 21 patients with limited stage NFL. The median age was 56 and 55 years, respectively. The histologic features were compared, as well as treatment modalities and response. Treatment of PCFL consisted of restricted field radiotherapy (RT), chemotherapy (CHT) and combined modalities (CM) in 12, 5 and 5 cases, respectively. Among the 21 patients with NFL, RT was employed in 13, CHT in 7 and the CM in one patient. The response to treatment was: 17 complete responses, CR (12 RT, 2 CHT, 3 CM), 3 partial responses, PR (1 CHT, 2 CM) and 2 non-responses, NR (2 CHT) in the PCFL group, while in the NFL group 18 patients attained CR (13 RT, 4 CHT, 1 CM) and 3 PR (3 CHT). The relapse rate was 22.7 and 28.5% in PCFL and NFL, respectively (median follow up of 48 and 50 months). The estimated 4 years event free survival (EFS) in the PCFL and NFL patients were 68 and 70%, respectively, (P = 0.83). The estimated 4 years overall survival (OS) in the PCFL and NFL groups were 90% and 100% respectively, (P = 0.254). Among the 22 patients with PCFL, there was a higher incidence of large cells than in NFL, although the differences were not significant (P = 0.08). In conclusion, despite histologic (higher proportion of large cells) and biologic differences, cutaneous and limited stage NFL show similar responses to treatment, with similar relapse rates, EFS and OS.