CD99 (MIC-2 or p30/32) has an unknown function, but has been found to be expressed in vitally all cases of primitive neuroectodermal tumors (PNETs) and Ewing sarcoma. The specificity is more limited and may be seen in alveolar rhabdomyosarcomas (15%), ALLs (90%), neuroendocrine carcinomas (20%), melanomas, etc. Therefore, CD99 should not be interpreted alone, and is best used as part of a panel (e.g. AE1/AE3, desmin, S-100, and CD45 in an undifferentiated small round blue cell tumor situation).
Note: CD99 was originally described as being sensitive and “specific” for PNETs. However, expression in a variety of other tumors (including tumors with similar morphologies to PNETs) were also found to have expression (at least in a subset of cases). Sensitivity of “new” IHC markers can be determined with a fair degree of accuracy using tissue arrays and large tumor libraries, but it usually takes time with efforts from many different laboratories to fully characterize the “specificity” of a marker. This should always be taken into consideration when relying heavily on a “new” marker for diagnostic significance.
Rao, N., Colby, T. V., Falconieri, G., Cohen, H., Moran, C. A., & Suster, S. (2013). Intrapulmonary solitary fibrous tumors: clinicopathologic and immunohistochemical study of 24 cases. The American Journal of Surgical Pathology, 37(2), 155–166. doi:10.1097/PAS.0b013e31826a92f5
CD117 (c-kit) is a member of the type III tyrosine kinase receptor family, and is a transmembrane protein. Immunohistochemical expression of CD117 can be seen in many different normal tissue components (e.g. mast cells) and neoplastic tissues. Therefore, CD117 should be used in a careful targeted manner; usually as part of a larger panel. Limitations of specificity should always be kept in mind.
Renal Tumors: Chromophobe RCC (83-100%, Oncocytoma (71-100%), negative in other subtypes of RCC
Hematopoietic
CD117 is most often used as a myeloblast marker in bone marrow biopsies, and to identify GISTs. It is important to understand what else may stain with CD117 (bright staining of mast cells in BM bxs., compared to dim staining of blasts), so one does not misinterpret the expression pattern. Erythroid precursor cell may also express CD117, which may cause confusion when evaluating for myeloblast percentage. Ohgami recommends using CD117, E-cadherin, and CD34 in combination in this situation. CD71 (erythroid precursor marker) may also be helpful.
Renal Tumors
CD117 has been found to be expressed in 71-100% of oncocytomas and 83-100% of chromophobe renal cell carcinomas with other subtypes of renal cell carcinoma being non-reactive. Therefore, CD117 may be a useful part of a larger panel (e.g. RCCMa, CD10, Vimentin, and cytokeratin) to diagnosis and subtype renal tumors (especially granular cell variant of RCC vs. chromophobe RCC or oncocytoma).
GIST
Approximately 95% of gastrointestinal stromal tumors (GIST) will react with CD117 by immunohistochemistry. It is important to emphasize that CD117 expression does not necessarily correlate with response to imatinib therapy (tyrosine kinase inhibitor). Lack of reactivity with CD117 should not exclude a patient from imatinib therapy. CD117 negative (kit-negative) GIST often contain PDGFRA mutations, which may be sensitive to imatinib. Sometimes weak expression of CD117 may be seen in non-GIST tumors, and this marker should be used as part of a larger panel incorporating the differential diagnosis (e.g. S-100, Desmin, CD34). DOG-1 antibody may be expressed in CD117 negative GIST cases, which may serve as an alternative marker.
Photomicrographs
CD117 expression in a gastrointestinal stromal tumor (GIST).CD117 highlighting scattered mast cells in a bone marrow biopsy.CD117 highlighting areas of blasts in CMML.CD117 expression in myeloblasts in a case of AML M6b.
References:
Wick, MR. “Immunohistochemical approaches to the diagnosis of undifferentiated malignant tumor.”Annals of Diagnostic Pathology12(2008):72-84.
Leidy, J., Khan, A., & Kandil, D. (2014). Basal-like breast cancer: update on clinicopathologic, immunohistochemical, and molecular features. Archives of Pathology & Laboratory Medicine, 138(1), 37–43. doi:10.5858/arpa.2012-0439-RA
Huang, Q., Wu, H., Nie, L., Shi, J., Lebenthal, A., Chen, J., et al. (2013). Primary high-grade neuroendocrine carcinoma of the esophagus: a clinicopathologic and immunohistochemical study of 42 resection cases. The American Journal of Surgical Pathology, 37(4), 467–483. doi:10.1097/PAS.0b013e31826d2639
Dunphy, C. H., O’Malley, D. P., Perkins, S. L., & Chang, C.-C. (2007). Analysis of immunohistochemical markers in bone marrow sections to evaluate for myelodysplastic syndromes and acute myeloid leukemias. Applied Immunohistochemistry & Molecular Morphology : AIMM / Official Publication of the Society for Applied Immunohistochemistry, 15(2), 154–159. doi:10.1097/PAI.0b013e318030dec7
Patil, D. T., & Rubin, B. P. (2011). Gastrointestinal stromal tumor: advances in diagnosis and management. Archives of Pathology & Laboratory Medicine, 135(10), 1298–1310. doi:10.5858/arpa.2011-0022-RA
Bénet, C., Gomez, A., Aguilar, C., Delattre, C., Vergier, B., Beylot-Barry, M., et al. (2011). Histologic and immunohistologic characterization of skin localization of myeloid disorders: a study of 173 cases. American Journal of Clinical Pathology, 135(2), 278–290. doi:10.1309/AJCPFMNYCVPDEND0
Al-Ghawi, H., Asojo, O. A., Truong, L. D., Ro, J. Y., Ayala, A. G., & Zhai, Q. J. (2010). Application of Immunohistochemistry to the Diagnosis of Kidney Tumors. Pathology Case Reviews, 15(1), 25–34. doi:10.1097/PCR.0b013e3181d51c70
Liegl-Atzwanger, B., Fletcher, J. A., & Fletcher, C. D. M. (2010). Gastrointestinal stromal tumors. Virchows Archiv : an International Journal of Pathology. doi:10.1007/s00428-010-0891-y
Siegert, S. I., Diebold, J., Ludolph-Hauser, D., & Löhrs, U. (2004). Are gastrointestinal mucosal mast cells increased in patients with systemic mastocytosis? American Journal of Clinical Pathology, 122(4), 560–565. doi:10.1309/2880-LF7Q-6XK3-HA3Q
Antonescu, C. R. (2008). Targeted therapy of cancer: new roles for pathologists in identifying GISTs and other sarcomas. Modern Pathology : an Official Journal of the United States and Canadian Academy of Pathology, Inc, 21 Suppl 2, S31–6. doi:10.1038/modpathol.2008.9
Medeiros, F., Corless, C. L., Duensing, A., Hornick, J. L., Oliveira, A. M., Heinrich, M. C., et al. (2004). KIT-negative gastrointestinal stromal tumors: proof of concept and therapeutic implications. The American Journal of Surgical Pathology, 28(7), 889–894.
Wang, H.-Y., & Mills, S. E. (2005). KIT and RCC are useful in distinguishing chromophobe renal cell carcinoma from the granular variant of clear cell renal cell carcinoma. The American Journal of Surgical Pathology, 29(5), 640–646.
Ohgami, R. S., Chisholm, K. M., Ma, L., & Arber, D. A. (2014). E-Cadherin Is a Specific Marker for Erythroid Differentiation and Has Utility, in Combination With CD117 and CD34, for Enumerating Myeloblasts in Hematopoietic Neoplasms. American Journal of Clinical Pathology, 141(5), 656–664. doi:10.1309/AJCP8M4QQTAZPGRP
CD138 (Syndecan-1) is expressed in mesenchymal and epithelial cells. In the bone marrow hematopoietic cells, CD138 is a specific (and sensitive) marker for plasma cells (e.g. multiple myeloma). The biggest pitfall in utilization of CD138 is plasmacytoid neoplasms showing expression of CD138 without consideration of a non-hematopoietic neoplasm expressing CD138!! Always consider a metastatic process in the bone marrow, and utilize additional markers (AE1/AE3, kappa/lambda) to exclude/prove plasma cells origin.
The majority of epithelial neoplasms express CD138, and even a significant number of osteosarcomas, osteoid osteomas, and osteoblastomas react with CD138. Recent literature suggests CD138 to be an adverse prognostic indicator in advanced and nonluminal subtype breast carcinomas.
Photomicrographs
CD138 highlighting plasma cells in a bone marrow with multiple myeloma.Combined CD138-Ki67 stain in a case of multiple myeloma.CD138 highlighting plasma cell in a bone marrow biopsy.CD138 highlighting benign plasma cells with a perivascular cuffing pattern.
Nunez, A. L., Siegal, G. P., Reddy, V. V. B., & Wei, S. (2012). CD138 (syndecan-1) expression in bone-forming tumors. American Journal of Clinical Pathology, 137(3), 423–428. doi:10.1309/AJCP6V4YPFBOCYXG
Nguyen, T. L., Grizzle, W. E., Zhang, K., Hameed, O., Siegal, G. P., & Wei, S. (2013). Syndecan-1 overexpression is associated with nonluminal subtypes and poor prognosis in advanced breast cancer. American Journal of Clinical Pathology, 140(4), 468–474. doi:10.1309/AJCPZ1D8CALHDXCJ
Joshi, R., Horncastle, D., Elderfield, K., Lampert, I., Rahemtulla, A., & Naresh, K. N. (2008). Bone marrow trephine combined with immunohistochemistry is superior to bone marrow aspirate in follow-up of myeloma patients. Journal of Clinical Pathology, 61(2), 213–216. doi:10.1136/jcp.2007.049130
CD34 (human hematopoietic progenitor cell antigen) is expressed by endothelial cells and embryonic cells of the hematopoetic system. CD34 is used in a wide variety of ways in diagnostic pathology. It can generally be divided into hematopathology and non-hematopathology uses. As with most situations in diagnostic immunohistochemistry, CD34 is often best used as part of a targeted panel considering the differential diagnosis at hand.
Hematopathology– CD34 will mark myeloblasts and a subset of lymphoblasts. It is therefore not specific for myeloid differentiation (although fairy sensitive). Normal myeloblasts will express CD34, and in cases of AML approximately 70% of cases will be positive. Approximately 1/3rd of cases of ALL may express CD34. It is also important to understand that not all blasts within a specific case may all express CD34, and correlation with flow cytometry data and aspirate count is critical. CD34 also stains vascular endothelium, which makes for a nice internal control in bone marrow biopsies. Granulocytic sarcomas (a.k.a. chloroma, soft tissue AML, or leukemia cutis) often have monocytic differentiation, and only ~5% of case demonstrate CD34 expression.
Non-Hematopathology– CD34 is expressed in cases of dermatofibrosarcoma protuberant (DFSP), hemangiopericytoma, solitary fibrous tumor, angiosarcoma & Kaposi’s sarcoma (>85%), epithelioid sarcoma (often), lymphocyte rich T cell lymphoma, gastrointestinal stromal tumors, and spindle cell lipomas. CD34 is not expressed in dermatofibromas, desmoplastic mesothelioma, & endometrial stromal sarcoma. CD34 is also an excellent vascular marker, which is helpful in identifying lymph-vascular invasion and tumors of vascular origin.
In hepatocellular carcinoma, CD34 highlights increased vascular structures associated with tumorigenesis. Normal liver only shows CD34 expression in portal vasculature and sinusoids immediate adjacent to portal tracts.
Lymphatic & Vascular Invasion – CD34 is sometimes utilized to evaluate for “lymphovascular invasion” (LVI) in different tumors (e.g. breast more commonly). CD34 and CD31 will stain both (blood) vascular endothelium (strong & sensitive) and also lymphatic endothelium (variable & less sensitive). Sometimes CD34 will stain stromal cells, which can mimic endothelium (false positive).
To determine the true nature of LVI (i.e. lymphatic vs. blood vascular invasion) additional markers specific for lymphatic endothelium (podoplanin or D2-40) need to be performed, and comparison made to CD31/CD34 for determination of invasion type:
Gastrointestinal Stromal Tumor (~70%, some smooth muscle neoplasms can express CD34 – up to 10%)
Spindle Cell Lipoma
Epithelioid Sarcoma
Subset of numerous other entities
Photomicrographs
CD34 expression in a case of acute lymphoblastic leukemia/lymphoma (ALL).CD34 expression in a spindle cell lipoma.CD34 expression in a gastrointestinal stromal tumor.CD34 expression in a case of DFSP.CD34 (red) – CD71 (brown) double stain in a case of AML.CD34 highlighting lymphovascular invasion of breast carcinoma.
References
Mohammed RAA, Martin SG, Gill MS, Green AR, Paish EC, Ellis IO. Improved methods of detection of lymphovascular invasion demonstrate that it is the predominant method of vascular invasion in breast cancer and has important clinical consequences. Am J Surg Pathol. 2007;31: 1825–1833. doi:10.1097/PAS.0b013e31806841f6
Yang H, Yu L. Cutaneous and Superficial Soft Tissue CD34(+) Spindle Cell Proliferation. Arch Pathol Lab Med. 2017;141: 1092–1100. doi:10.5858/arpa.2016-0598-RA
Rao N, Colby TV, Falconieri G, Cohen H, Moran CA, Suster S. Intrapulmonary solitary fibrous tumors: clinicopathologic and immunohistochemical study of 24 cases. Am J Surg Pathol. 2013;37: 155–166. doi:10.1097/PAS.0b013e31826a92f5
de Smet D, Trullemans F, Jochmans K, Renmans W, Smet L, Heylen O, et al. Diagnostic Potential of CD34+ Cell Antigen Expression in Myelodysplastic Syndromes. Am J Clin Pathol. 2012;138: 732–743. doi:10.1309/AJCPAGVO27RPTOTV
Rosado FGN, Itani DM, Coffin CM, Cates JM. Utility of immunohistochemical staining with FLI1, D2-40, CD31, and CD34 in the diagnosis of acquired immunodeficiency syndrome-related and non-acquired immunodeficiency syndrome-related Kaposi sarcoma. Arch Pathol Lab Med. 2012;136: 301–304. doi:10.5858/arpa.2011-0213-OA
Patil DT, Rubin BP. Gastrointestinal stromal tumor: advances in diagnosis and management. Arch Pathol Lab Med. 2011;135: 1298–1310. doi:10.5858/arpa.2011-0022-RA
Bénet C, Gomez A, Aguilar C, Delattre C, Vergier B, Beylot-Barry M, et al. Histologic and immunohistologic characterization of skin localization of myeloid disorders: a study of 173 cases. Am J Clin Pathol. 2011;135: 278–290. doi:10.1309/AJCPFMNYCVPDEND0
Dunphy CH, O’Malley DP, Perkins SL, Chang C-C. Analysis of immunohistochemical markers in bone marrow sections to evaluate for myelodysplastic syndromes and acute myeloid leukemias. Appl Immunohistochem Mol Morphol. 2007;15: 154–159. doi:10.1097/PAI.0b013e318030dec7
Dunphy CH, Polski JM, Evans HL, Gardner LJ. Evaluation of bone marrow specimens with acute myelogenous leukemia for CD34, CD15, CD117, and myeloperoxidase. Arch Pathol Lab Med. 2001;125: 1063–1069.
Wang HL, Kim CJ, Koo J, Zhou W, Choi EK, Arcega R, et al. Practical Immunohistochemistry in Neoplastic Pathology of the Gastrointestinal Tract, Liver, Biliary Tract, and Pancreas. Arch Pathol Lab Med. 2017;141: 1155–1180. doi:10.5858/arpa.2016-0489-RA
Wick, MR. “Immunohistochemical approaches to the diagnosis of undifferentiated malignant tumor.”Annals of Diagnostic Pathology12(2008):72-84.
CD31 (PECAM-1) is thought of as a highly sensitive and specific marker for vascular endothelium. It is helpful to identify tumors of vascular origin, and also to identify lympho-vascular invasion by tumors. CD31 may also stain monocytes, megakaryocytic, and granulocytes in addition to endothelial cells. Plasma cells may variably express CD31 (reactive PCs more common). CD31 (like CD34) is more sensitive (and stronger staining) for blood vascular endothelium compared to lymphatic endothelium (less sensitive and variable staining).
Lymphatic & Vascular Invasion
CD31 is sometimes utilized to evaluate for “lymphovascular invasion” (LVI) in different tumors (e.g. breast more commonly). CD34 and CD31 will stain both (blood) vascular endothelium (strong & sensitive) and also lymphatic endothelium (variable & less sensitive). To determine the true nature of LVI (i.e. lymphatic vs. blood vascular invasion) additional markers specific for lymphatic endothelium (podoplanin or D2-40) need to be performed, and comparison made to CD31/CD34 for determination of invasion type:
Kaposi sarcoma is a vascular neoplasm associated with immunodeficiency (usually HIV/AIDS) and is caused by human herpesvirus 8 (HHV-8). Vascular markers (CD31, CD34, D2-40, and FLI1) are helpful (in combination with HHV-8) for diagnosis. CD31 is expressed in 58-75% of cases (strong and diffuse staining). CD34 is considered more sensitive (92%).
Photomicrographs
CD31 highlighting vasculature in a normal section of kidney.
References
Wick, MR. “Immunohistochemical approaches to the diagnosis of undifferentiated malignant tumor.”Annals of Diagnostic Pathology12(2008):72-84.
Vanchinathan V, Mirzamani N, Mizramani N, Kantipudi R, Schwartz EJ, Sundram UN. The vascular marker CD31 also highlights histiocytes and histiocyte-like cells within cutaneous tumors. Am J Clin Pathol. 2015;143: 177–85– quiz 305. doi:10.1309/AJCPRHM8CZH5EMFD
Rosado FGN, Itani DM, Coffin CM, Cates JM. Utility of immunohistochemical staining with FLI1, D2-40, CD31, and CD34 in the diagnosis of acquired immunodeficiency syndrome-related and non-acquired immunodeficiency syndrome-related Kaposi sarcoma. Arch Pathol Lab Med. 2012;136: 301–304. doi:10.5858/arpa.2011-0213-OA
Morgado JMT, Sánchez-Muñoz L, Teodósio CG, Jara-Acevedo M, Álvarez-Twose I, Matito A, et al. Immunophenotyping in systemic mastocytosis diagnosis: ‘CD25 positive’ alone is more informative than the “CD25 and/or CD2” WHO criterion. Mod Pathol. 2012;25: 516–521. doi:10.1038/modpathol.2011.192
Mohammed RAA, Martin SG, Gill MS, Green AR, Paish EC, Ellis IO. Improved methods of detection of lymphovascular invasion demonstrate that it is the predominant method of vascular invasion in breast cancer and has important clinical consequences. Am J Surg Pathol. 2007;31: 1825–1833. doi:10.1097/PAS.0b013e31806841f6
CD30 (Ki-1 antigen) is a member of the tumor necrosis receptor factor family (TNRF) and is not a specific marker. CD30 will mark activated benign lymphoid cells in addition to several characteristic lymphoproliferative disease subtypes (e.g. Classical Hodgkin lymphoma and anapestic large cell lymphoma) of both B-cell and T-cell lineages.
CD30 Expression Pattern
Benign “Activated” lymphoid cells
EBV-driven lymphoproliferative disorders and reactive proliferations (e.g. mononucleosis)
CD30 is an “activation” marker on T and B cells. This marker is most often used in the work-up of cases of Hodgkin lymphoma, anaplastic large cell lymphoma (ALCL), and embryonal carcinoma. The staining pattern has a membraneous and Golgi pattern. B5 fixative has negative impact on staining. CD30 is also helpful in the diagnosis of mediastinal large B cell lymphoma (focal/patchy and dim staining).
Unfortunately, CD30 lacks specificity, and in addition to the staining pattern in normal cells compartments, it may also be expressed in a variety of disease processes including: peripheral T-cell lymphoma (occasional), primary effusion lymphoma, cutaneous CD30+ lymphoproliferative disorders, DLBCL (variable, focal), plasmablastic lymphoma, sinonasal NK/T cell lymphoma, embryonal carcinoma of the testis (100%), Yolk sac tumors (24%), & mesothelioma (rare).
Nodular LP Hodgkin lymphoma, Adult T cell leukemia/lymphoma, pre B ALL, and systemic mastocytosis should not express CD30.
CD30+ DLBCL
Cases of DLBCL which co-express CD30 (~14%, n=903) had a more favorable 5-year survival (79% vs. 59%) in both germinal center and activated B-cell phenotypes. Gene expression profiling (GEP) revealed down regulation of proliferation and B-cell receptor signaling with up regulation of nuclear factor kappaB activation and lymphocyte survival. CD30+ EBV+ DLBCLis a unique subset of lymphomas with an aggressive clinical course. The WHO classification separates EBV+ cases into a separate category.
CD30 expression in a diffuse large B-cell lymphoma. CD30+ cases are associated with a relatively good prognosis (excluding EBV+ cases).CD30 (red) showing variable expression and co-expression of PAX-5 (variable dim brown nuclear expression) in classical Hodgkin lymphomaCD30 expression in classical Hodgkin lymphoma (CHL).Anaplastic Large Cell Lymphoma (ALCL) with strong diffuse expression of CD30.
Clinical Significance
Brentuximab vedotin (Adcetris®) is an anti-CD30 monoclonal antibody used to treat anaplastic large cell lymphoma and relapsed or refractory Hodgkin lymphoma. Ongoing research with promise is active in other CD30 positive neoplastic processes.
References
Wick, MR. “Immunohistochemical approaches to the diagnosis of undifferentiated malignant tumor.”Annals of Diagnostic Pathology12(2008):72-84.
Hu S, Xu-Monette ZY, Balasubramanyam A, Manyam GC, Visco C, Tzankov A, et al. CD30 expression defines a novel subgroup of diffuse large B-cell lymphoma with favorable prognosis and distinct gene expression signature: a report from the International DLBCL Rituximab-CHOP Consortium Program Study. Blood. 2013;121: 2715–2724. doi:10.1182/blood-2012-10-461848
Ansell SM. Brentuximab vedotin. Blood. 2014. doi:10.1182/blood-2014-06
CD25 is an IL-2 receptor. CD25 is most often used as a marker for hairy cell leukemia, systemic mastocytosis, and adult T cell leukemia/lymphoma. CD25 may stain activated B and T cells and cases of lymphoplasmacytic lymphoma (LPL). CD25 is similar to CD30 in that it is an “activation” marker, and not specific. Macrophages, and osteoblasts also often express CD25.
Non-neoplastic mast cells, marginal zone B cell lymphoma, T cell large granular leukemia/lymphoma, and variant hairy cell leukemia are usually negative for CD25.
Diagnostic Immunohistochemistry: Theranostic and Genomic Applications [edited by] David J. Dabbs. 3rd Edition. pp. 165.
Lin, P., Molina, T. J., Cook, J. R., & Swerdlow, S. H. (2011). Lymphoplasmacytic lymphoma and other non-marginal zone lymphomas with plasmacytic differentiation. American Journal of Clinical Pathology, 136(2), 195–210. doi:10.1309/AJCP8FOIVTB6LBER
Karube, K., Suzumiya, J., Okamoto, M., Takeshita, M., Maeda, K., Sakaguchi, M., et al. (2007). Adult T-cell lymphoma/leukemia with angioimmunoblastic T-cell lymphomalike features: Report of 11 cases. The American Journal of Surgical Pathology, 31(2), 216–223. doi:10.1097/01.pas.0000213325.79368.2c
Siegert, S. I., Diebold, J., Ludolph-Hauser, D., & Löhrs, U. (2004). Are gastrointestinal mucosal mast cells increased in patients with systemic mastocytosis? American Journal of Clinical Pathology, 122(4), 560–565. doi:10.1309/2880-LF7Q-6XK3-HA3Q
Lin, P., & Medeiros, L. J. (2005). Lymphoplasmacytic lymphoma/waldenstrom macroglobulinemia: an evolving concept. Advances in Anatomic Advances in Anatomic Pathology, 12(5), 246–255.
CD23 is a transmembrane glycoprotein expressed by different hematopoietic cells and is a low-affinity receptor for IgE. It is also involved in promoting survival of B-cells in the germinal center. CD23 is useful as a follicular cell dendritic cell marker and is classically expressed in cases of CLL/SLL. CD23 has been identified in many types of lymphomas, but is most commonly used to differentiate between CLL/SLL (CD23+) and mantle cell lymphoma (CD23-). This testing is typically performed by flow cytometry, but immunohistochemisty for CD23 is available. Expression of CD23 has been associated with better prognosis (at least in limited published data) in follicular lymphoma, CLL/SLL, mantle cell lymphoma, and diffuse large B-cell lymphoma dependent upon expression characteristics. CD23 is not commonly performed/used as a prognostic marker for B-cell lymphomas.
Rarely CD23 may be expressed in cases of Hairy cell leukemia (17%) and DLBCL (16%). Approximately 70% of Mediastinal large B-cell lymphoma cases express CD23. Practically, this IHC marker is used as a follicular dendritic cell marker and to help differentiate CLL/SLL from mantle cell lymphoma. Follicular dendritic cell tumors will also express CD23 like CD21. CD21 is more sensitive compared to CD23 as a follicular dendritic marker.
Follicular Lymphoma (FL)– CD23 has been found to be expressed in some cases of FL, especially from inguinal lymph nodes, and prognosis appears comparatively better. Olteanuet. al found that 87% of inguinal lymph nodes expressed CD23, compared to 61% from other sites, and that survival was prolonged more in CD23+ cases.
Diffuse Large B-Cell Lymphoma – A subset of DLBCLs may express CD23, which may have a better prognosis (CD23 is not commonly performed for this purpose).
Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL)– CD23 expression is characteristic of CLL/SLL, particularly in comparison to another CD5+ lymphoma, mantle cell lymphoma. Strong membrane expression has been associated with a better outcome. DiRaimondo,et. al found ~6% of CLL cases to be CD23 negative (flow cytometry), and they had a worse prognosis. Many of these cases may have been misdiagnosed mantle cell lymphomas.
Mantle Cell Lymphoma (MCL)– CD23 is characteristically negative in MCL, which helps to differentiate it from CLL/SLL. However, ~21% of cases of MCL were found to be CD23+ by Gao,et. al, and other studies have shown CD23 expression in MCL ranging from 0% to 45% (most data appears to be based on flow cytometry).
CD23 Expression Pattern
CLL/SLL – characteristically expressed (6% may be negative, probably much lower)
Mantle cell lymphoma may be CD23+ (21%+, 0-45%)
B-cell Lymphomas (e.g. some DLBCL and follicular lymphomas may show expression)
Follicular Dendritc Cells (not as sensitive as CD21)
B-cells in mantle zone of lymphoid follicles
Photomicrographs
CD23 expression highlighting follicular dendritic meshwork in a normal tonsil.
Linderoth J, Jerkeman M, Cavallin-Stahl E, et al. Immunohistochemical expression of CD23 and CD40 may identify prognostically favorable subgroups of diffuse largeB-cell lymphoma: a Nordic Lymphoma Group Study.ClinCancer Res.2003;9:722-728.
Olteanu H, Fenske TS, Harrington AM, Szabo A, He P, Kroft SH. CD23 Expression in Follicular Lymphoma: Clinicopathologic Correlations. Am J Clin Pathol. 2011;135: 46–53. doi:10.1309/AJCP27YWLIQRAJPW
Gao J, Peterson L, Nelson B, Goolsby C, Chen Y-H. Immunophenotypic variations in mantle cell lymphoma. Am J Clin Pathol. 2009;132: 699–706. doi:10.1309/AJCPV8LN5ENMZOVY
Troxell ML, Schwartz EJ, van de Rijn M, Ross DT, Warnke RA, Higgins JP, et al. Follicular dendritic cell immunohistochemical markers in angioimmunoblastic T-cell lymphoma. Appl Immunohistochem Mol Morphol. 2005;13: 297–303.
Dalton RR, Admirand JH, Medeiros LJ. Small Lymphocytic Lymphoma. Pathology Case Reviews. 2004;9: 7.
DiRaimondo F, Albitar M, Huh Y, O’Brien S, Montillo M, Tedeschi A, et al. The clinical and diagnostic relevance of CD23 expression in the chronic lymphoproliferative disease. Cancer. 2002;94: 1721–1730. doi:10.1002/cncr.10401
During the months of August and September, 2017 American Airlines showed this ASCP video on domestic US flights highlighting the contribution of pathologists and laboratory professionals to healthcare.
ZAP-70 (zeta-associated protein-70) is a surrogate marker for the somatic mutation status of immunoglobulin heavy chain (IGHV) in CLL. Unfortunately, attempts to utilize flow cytometry for this purpose has resulted in unreliable results. ZAP-70 expression by IHC has been shown to have an increased risk of progression to therapy requirement (3-yr risk 83% vs. 31% for ZAP-70 negative) [Modern Pathology (2010)23,1518-1523]. ZAP-70 expression is not specific to CLL, and is not particularly useful for tumor sub-classification/prognosis outside the setting of CLL.
ZAP-70 expression in B-cell lymphoid neoplasms (Carreras, J, et al).
Lymphoid Disorder
No.
ZAP-70 + (%)
Lymphoblastic Lymphoma
7
28%
Chronic Lymphocytic Leukemia
52
65%
Mantle Cell Lymphoma
36
8%
Classical
28
11%
Blastoid
8
0%
Follicular Lymphoma
19
0%
Marginal Zone Lymphoma
23
4%
MALT
11
0%
Nodal
5
20%
Splenic
7
0%
Diffuse Large B-Cell Lymphoma
45
2%
Burkitt Lymphoma
29
31%
Hodgkin Lymphoma
14
0%
Stain Interpretation
ZAP-70 is interpreted as negative or positive. The minimum positive expression is weakly positive( 1+) staining defined as granular cytoplasmic staining with nuclear blush in a majority of tumor cells. Strong positivity (2+) is defined as strong expression in a majority of tumor cells.
ZAP-70 will also stain T-cells in the background. Therefore, ZAP-70 should be interpreted with the accompaniment of CD3 and CD20, so that there is clear discernment between tumor and background lymphoid cells.
IHC on Peripheral Blood
One of the big problems to identify ZAP-70 expression in CLL is the material available for evaluation. Most material is based on peripheral blood, and flow cytometry has been difficult to analyze reliably for ZAP-70 expression. An alternative is to perform PERIPHERAL BLOOD MONONUCLEAR CELL (PBMC) PURIFICATION AND CELL BLOCK PREPARATION as described by Roullet, et. al. in which a cell block is prepared from peripheral blood on which IHC for ZAP-70 can be reliably performed. Please review Roullet’s article for complete technical details.
Photomicrographs
ZAP-70 – Benign Tonsil
ZAP-70 weak expression in CLL with an unmutated IgVH gene (poor prognosis). Strong staining in background T-cells.
ZAP-70 weak expression in CLL with an unmutated IgVH gene (poor prognosis)
References
Admirand, J. H., Knoblock, R. J., Coombes, K. R., Tam, C., Schlette, E. J., Wierda, W. G., et al. (2010). Immunohistochemical detection of ZAP70 in chronic lymphocytic leukemia predicts immunoglobulin heavy chain gene mutation status and time to progression. Modern Pathology : an Official Journal of the United States and Canadian Academy of Pathology, Inc, 23(11), 1518–1523. doi:10.1038/modpathol.2010.131
Carreras, J., Villamor, N., Colomo, L., Moreno, C., Ramón y Cajal, S., Crespo, M., et al. (2005). Immunohistochemical analysis of ZAP-70 expression in B-cell lymphoid neoplasms. The Journal of Pathology, 205(4), 507–513. doi:10.1002/path.1727
Roullet, M., Sargent, R., Pasha, T., Cajiao, I., Elstrom, R., Smith, T., et al. (2007). ZAP70 expression assessed by immunohistochemistry on peripheral blood: a simple prognostic assay for patients with chronic lymphocytic leukemia. Applied Immunohistochemistry & Molecular Morphology : AIMM / Official Publication of the Society for Applied Immunohistochemistry, 15(4), 471–476. doi:10.1097/01.pai.0000213152.41440.34
Crespo, M., Bosch, F., Villamor, N., Bellosillo, B., Colomer, D., Rozman, M., et al. (2003). ZAP-70 expression as a surrogate for immunoglobulin-variable-region mutations in chronic lymphocytic leukemia. The New England Journal of Medicine, 348(18), 1764–1775. doi:10.1056/NEJMoa023143
