Prognostic factors in primary cutaneous large B-cell lymphomas: a European multicenter study

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Primary cutaneous B-cell lymphomas (PCLBCL) generally have a good prognosis.
• Primary cutaneous large B-cell lymphomas (PCLBCL) of the leg are considered a distinct entity with a worse prognosis according to the European Organization for Research and Treatment of Cancer (EORTC) classification.
• The prognostic significance of tumor location in PCLBCL remains debated.

Purpose of the Study:

• To identify independent prognostic factors in a large European multicenter series of PCLBCL.
• To evaluate the prognostic impact of tumor site, morphology, and number of lesions in PCLBCL.

Main Methods:

• Clinical and histological data from 145 patients with PCLBCL were analyzed.
• Patients were classified according to the EORTC criteria into PCLBCL of the leg (48 patients) and primary cutaneous follicle center-cell lymphoma (PCFCCL) (97 patients).
• Univariate and multivariate survival analyses were performed using a Cox proportional hazards model.

Main Results:

• PCLBCL of the leg showed older age at onset, shorter history of lesions, round-cell morphology, and positive bcl-2 staining compared to PCFCCL.
• Five-year disease-specific survival was significantly lower for PCLBCL of the leg (52%) versus PCFCCL (94%).
• Multivariate analysis identified round-cell morphology, leg location, and multiple skin lesions as independent adverse prognostic factors for PCLBCL survival.

Conclusions:

• Round-cell morphology is an adverse prognostic factor in both PCLBCL of the leg and PCFCCL.
• Multiple skin lesions are associated with a poor prognosis specifically in PCLBCL of the leg.
• Site, morphology, and number of tumors are crucial for guiding PCLBCL management.