Maimai’s Pathology Weekly Reading Notes Issue 8 | Immunohistochemical Markers for Respiratory and Lung Tumors (Part 2)

Posted by

6 2 月, 2026

On 6 2 月, 2026

Preface:

Based on the content arrangement of the book “Immunohistochemistry in Tumor Diagnostics” published by Springer, this article “Mai Mai” will focus on compiling and introducing knowledge points related to immunohistochemical markers for thymic epithelial tumors, as well as cardiac and pericardial tumors.tocheTEXT_3

Immunohistochemical Markers for Respiratory Tract and Lung Tumors

Although this article focuses on thymic epithelial tumors, given the significant lymphoid stromal components in related lesions, the immunohistochemical markers for thymic epithelial tumors mainly focus on two situations:

1. Immunohistochemical markers for thymic epithelium, such as Pax-8, CD117, CD5, CK (high molecular weight), p63.

Pax-8 and CD117 help differentiate normal and neoplastic thymic epithelium from other epithelia or carcinomas: in both normal and neoplastic thymic epithelium, Pax-8 and CD117 are positive, while these two markers are negative in other epithelia or carcinomas.

Figure 1. Type AB thymoma, Pax-8 shows positive nuclear expression in neoplastic epithelial cells.

Figure 2. Thymic carcinoma, Pax-8 shows positive nuclear expression in malignant thymic epithelial cells.

Figure 3. Thymic carcinoma, CD117 shows positive expression in malignant thymic epithelium.

Figure 4. In type AB thymoma, CK5/14 shows positive cytoplasmic expression in neoplastic epithelial cells.

All benign and neoplastic (including all types of thymoma) thymic epithelial cells express p63, while CD5 can be considered a marker for malignant thymic epithelium (i.e., thymic carcinoma), and benign thymic epithelium does not express CD5.

2. Immunohistochemical markers for thymic lymphoid stroma, such as CD1a, CD3, TdT.

This part will be detailed in the section on lymphohematopoietic-related tumors, and refer to Table 1.

Table 1. Summary of Immunohistochemical Indicators for Thymic Epithelial Tumors

Notes for Table 1:

Type A and AB thymomas may also show positive expression of CD20;
In spindle cell thymic carcinoma, CD5 is negative.

Figure 5. In type AB thymoma, tumor-associated T lymphocytes are positive for CD1a.

Immunohistochemical Markers for Cardiac and Pericardial Tumors

Cardiac tumors include a group of tumors with significantly different tissue origins and morphologies. Their immunohistochemical manifestations depend on the tissue origin and specific morphological features, as detailed in Table 2.

Table 2. Summary of Immunohistochemical Indicators for Cardiac and Pericardial Tumors

Figure 6. Cardiac papillary fibroelastoma, vascular endothelial cells show positive immunohistochemical staining for CD31.

Figure 7. Cardiac myxoma, tumor cells strongly express calretinin.

Mai Mai: “Technology empowerment is the main theme of the era. Mastering core technologies and not being constrained by others is a prerequisite for innovative enterprises. In the fourth issue of “Mai Mai Reading,” we introduced the Maxin CloneDomesticCKseries of antibodies, which have received attention and praise from many pathology teachers. Today, we recommend several Maxin Clone antibodies related to the content of this article. You might want to try them when you have the opportunity.”

Antibody Name	Clone Number	Positive Control	Positive Location
^Actin	MX083	Colonic smooth muscle, appendix	Cytoplasm
Bcl-2	MX022	Tonsil, appendix	Membrane/cytoplasm
^CD5	MX052	Tonsil, thymus	Membrane
CD10	MX002	Tonsil, kidney	Cytoplasm/membrane
^CD31	MX032	Hemangioma, liver	Membrane
CD56	MX039	Small cell lung carcinoma, appendix	Membrane
^CD68	MX075	Malignant fibrous histiocytoma, tonsil	Cytoplasm
CEA	MX068	Lung adenocarcinoma, appendix	Cytoplasm
^CgA	MX018	Pheochromocytoma, neuroendocrine carcinoma	Cytoplasm
Desmin	MX046	Esophageal tissue, appendix	Cytoplasm
^HER-2	MXR001	Invasive ductal carcinoma of the breast	Membrane
MyoD1	MX049	Rhabdomyosarcoma	Nucleus
^p63	MX013	Prostatic hyperplasia, urothelial carcinoma	Nucleus
Pax-8	MX062	Renal clear cell carcinoma, fallopian tube	Nucleus
^SMA	MX097	Colonic smooth muscle, appendix	Cytoplasm
Syn	MX038	Pancreas, appendix	Cytoplasm
^Vimentin	MX034	Gastrointestinal stromal tumor, appendix	Cytoplasm

For more information, please contact: 800-8581156 or 400-889-9853

发表回复 取消回复

发表回复取消回复