Hierarchical clustering based on B-cell signature in primary cutaneous large B-cell lymphoma. Hierarchical clustering based on the expression of a B-cell signature consisting of 7450 genes with a “present” call in normal B-cell subsets (centroblasts, centrocytes, memory B cells, and naive B cells) and generated by the same Affymetrix U95Av2 Gene Chip²²  identifies 2 distinct gene expression profiles in primary cutaneous follicle center cell lymphoma (PCFCCL) and primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg).