CD30-positive T-cell lymphomas co-expressing CD15: an immunohistochemical analysis.

The characteristic histologic features and immunophenotype are usually diagnostic and allow distinguishing CD30 positive T-cell lymphoma (including anaplastic large cell lymphoma) from classical Hodgkin's lymphoma. The latter differs by expression of CD15 and lack of CD45, pan-T antigens and ALK expression. We report nine cases of large cell hematopoietic neoplasms in which the neoplastic cells co-expressed CD30 and CD15, and had immunophenotypic and morphologic features of T-cell lymphoproliferative process. The average age of the CD15-positive group was 61.9 years; 6 cases occurred in men and 3 in women. The tumors were located in lymph nodes in 8 cases, and in liver in 1 case. Two cases expressed ALK protein. There were no statistically significant differences in phenotypic parameters between the CD15-positive and CD15-negative neoplasms (p>0.05). However, the CD15-positive group appeared to show a minor trend toward less positivity for EMA (44% versus 72%), ALK protein (22% versus 51%), and CD45RO (33.3% versus 83.3%, p=0.07), when compared to the typical CD15-negative neoplasms. In summary, although the co-expression of CD30 and CD15 is typical for classical HL, it may be also present in a subset of peripheral T-cell neoplasms including ALK-positive anaplastic large cell lymphoma. Combined and sensible use of morphology and a broad immunophenotypic panel in cases with limited material and/or those with overlapping histologic patterns will best discriminate between HL and ALCL. It is incumbent upon the pathologist to distinguish between these two clinicopathologic entities, since treatment options and clinical outcomes differ.

Ultrafast Papanicolaou stain and cell-transfer technique enhance cytologic diagnosis of Hodgkin lymphoma.

Diagnosis of Hodgkin lymphoma (HL) by fine-needle aspiration (FNA) is often hampered by aspirated blood that camouflage scattered Hodgkin cells and Reed-Sternberg (HRS) cells, and the absence of HRS cells in the smears submitted for immunophenotyping. The objective of this study was to develop a simple protocol to overcome these problems. The visibility of HRS cells in Diff-Quik, traditional, and Ultrafast Papanicolaou (UFP) stains in FNA smears were compared in 73 cases of HL. HRS cells were found to be most visible in UFP because of the hemolysis of aspirated blood and the highlighting of HRS cells by the red-staining nucleoli. UFP-stained smears containing HRS cells were subsequently immunophenotyped via the cell-transfer technique. UFP staining was found to have no deleterious effect on the immunoreactivity of cellular CD15 and CD30 antigens of HRS cells. This simple protocol enhances the cytologic diagnosis of HL, feasible even with a single smear.