Primary Cutaneous B‐Cell Lymphoma: Management and Patterns of Recurrence at the Multimodality Cutaneous Lymphoma Clinic of The Ohio State University

Background. The increasing incidence of primary cutaneous B‐cell lymphomas (PCBCLs) presents new challenges for clinicians. Despite advances in the clinical and pathologic characterization of PCBCL, the significance of the current staging approach as a risk profiling tool and the effect of various treatments on outcome remain unclear. Materials and Methods. We retrospectively reviewed patients who presented with a diagnosis of PCBCL seen at The Ohio State University between 1998 and 2012. We reviewed the initial presentation and treatment modality. We then assessed whether the treatment modality (conservative skin‐directed vs. definitive radiation with or without systemic therapy), stage (T1 or ≥T2), or histologic subtype (primary cutaneous follicle center lymphoma [PCFCL] vs. primary cutaneous marginal zone B‐cell lymphoma [PCMZL]) affected the risk of recurrence. Results. We identified 67 patients referred with an initial diagnosis of PCBCL. After imaging, 12 did not meet the criteria for PCBCL and were classified as having systemic B‐cell lymphoma with cutaneous involvement. The remaining 55 patients included 25 with PCMZL, 24 with PCFCL, 2 with primary cutaneous large B‐cell lymphoma leg type, and 4 with unclassifiable disease. According to the International Society of Cutaneous Lymphoma‐European Organization for Research and Treatment of Cancer staging, 30 cases were T1 (55%), 14 T2 (25%), and 11 T3 (20%). Comparing the time to first recurrence (TFR) by indolent PCBCL subtypes, we found no difference in the recurrence risk for either stage (T1, p = .51 vs. T2/T3, p = .30). Comparing TFR by treatment modality, we found no difference in TFR within T1 patients (p = .34) or T2/T3 patients (p = .44). Conclusion. Our limited analysis highlights the importance of complete staging at diagnosis and suggests that the treatment modality does not affect the risk of recurrence in T1 indolent PCBCL. Implications for Practice: Primary cutaneous B‐cell lymphoma (PCBCL) is a rare malignancy with an increasing incidence. Clinicians must recognize the importance of a complete workup to accurately diagnose PCBCL, given the effect on prognosis and treatment. It was observed that nearly 20% of the patients who presented initially with cutaneous B‐cell lymphoma were classified as having systemic B‐cell lymphoma after whole body imaging. The findings from the present retrospective analysis of a single‐institution cohort suggest that for early‐stage indolent PCBCL, no front‐l