Template:Undifferentiated malignancy
Undifferentiated malignancy

An initial panel of cytokeratin (CK, such as by CK AE1/AE3 cocktail), S100, vimentin and LCA (CD45) can be used (see source article for subsequent work-up).[1]
Alternatively, a more comprehensive panel can be performed upfront, with the most pertinent panel suggested below (with main associated primary origins in parentheses), but it should be tailored to additional clues from each individual case:[2]
- Mucicarmine or Cytokeratin CAM 5.2 (adenocarcinoma)
- CK7 and CK20 can give a broad indication of the primary site. Still use more specific immunohistochemistry stains instead or in addition where applicable. See table below for main patterns.
- NKX3.1 in males (prostate adenocarcinoma), or PAX-8 or estrogen and progesterone receptor in females (female reproductive tract).
- TTF-1 (thyroid or lung tumor)
- GATA3 (urothelial carcinoma, breast tumor)
- CDX2 (gastrointestinal tumor)
- p63 (squamous cell carcinoma)
- S100 (neural, invasive melanoma)
- LCA (CD45) (hematopoietic)
- Synaptophysin (neuroendocrine)
| CK20 | |||
|---|---|---|---|
| Positive | Negative | ||
| CK7 | Positive |
|
|
| Negative |
|
| |
Notes
Main page
References
- ↑ Lin F, Liu H (2014). "Immunohistochemistry in undifferentiated neoplasm/tumor of uncertain origin. ". Arch Pathol Lab Med 138 (12): 1583-610. doi:. PMID 25427040. Archived from the original. .
- ↑ Partly inspired by:
Beauchamp K, Moran B, O'Brien T, Brennan D, Crown J, Sheahan K (2023). "Carcinoma of unknown primary (CUP): an update for histopathologists. ". Cancer Metastasis Rev. doi:. PMID 37394540. Archived from the original. . - ↑ Selves J, Long-Mira E, Mathieu MC, Rochaix P, Ilié M (2018). "Immunohistochemistry for Diagnosis of Metastatic Carcinomas of Unknown Primary Site. ". Cancers (Basel) 10 (4). doi:. PMID 29621151. PMC: 5923363. Archived from the original. .
- ↑ Elliot Weisenberg, M.D.. Esophagus - Carcinoma - Adenocarcinoma. Pathology Outlines. Last author update: 1 June 2013. Last staff update: 31 October 2022
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