Immunoblasts have round or oval vesicular nucleus, a single centrally located prominent nucleolus, and abundant basophilic cytoplasm. This image shows mostly immunoblasts. Lymphomas with >90% immunoblasts are called immunoblastic variant; the remainder (with <90% immunoblasts) are classified as centroblastic (large noncleaved cell) variant. Some immunoblastic lymphomas may show plasmacytoid features. Given the low degree of intraobserver and interobserver reproducibility, cytological subclassification of diffuse large B-cell lymphomas is not considered necessary.