CUP: Cancer Unknown Primary

Keywords/IHC markers/tests to remember for each tumour type

Carcinoma

Cytokeratin (AE1/3, EMA, Pankeratin)

Neuroendocrine carcinoma/Neuroendocrine features

CD56, chromogranin A, synaptophysin, INSM1

Lymphoma

CD45 (LCA)

Squamous cell carcinoma

CK5/6, p40, p63

Germ cell tumours

OCT3/4, PLAP, SALL4, CD117

Lung cancer

CK7+/CK20-, Napsin A, TTF1

Sarcoma

Desmin, Vimentin (negative for S100, CD45, AE1/3)

Gastro-oesophageal cancer

CK7+, CK20 (focal)

Liver cancer

AFP, arginase-1, glypican-3, HepPar-1, HSP70, glutamine synthetase

Breast cancer

CK7+/CK20-, ER/PR, GATA3, GCDFP-15, HER2, mammaglobin, mesothelin-ve

Bile duct cancer

CEA, CK7+, CK19, CK20 (focal)

Colorectal cancer

CK7 -ve, CK20+, SATB2, CDX2

Pancreas cancer

CA19-9, CDX (focal), CK7+, CK19+

RCC

PAX8, CAIX, CD10+

Mesothelioma

Calretinin, CK5/6, D2-40, WT1

Prostate cancer

NKX3.1, P504S, PAP, PSA

Endometrial cancer

CK7+, ER, PR, PAX8

Ovarian cancer

CK7+/CK20-, ER, PAX8, p53, WT1 (high grade serous), mesothelin+

Melanoma

S100, HMB-45, melan A, MITF-1, SOX10

Urothelial cancer

CK7+, CK20+, GATA3, thrombomodulin, uroplakin, p63, p40+

Thyroid carcinoma

TTF1, thyroglobulin, PAX8

Clear cell ovarian

PAX8, Napsin A, ARID1A

GIST

DOG1, CD117, c-KIT

CK7-/CK20-

• RCC

• Hepatocellular

• Prostate

• Adrenal

CK7+/CK20+

• Pancreas

• Gastric

• Cholangiocarcinoma

• Urothelial

• Mucinous ovarian