p63 in cutaneous adnexal neoplasms and adenocarcinoma metastatic to skin

p63 is expressed by normal skin epidermis and basal cells of adnexa but not by adenocarcinomas from other sites metastatic to the skin. p63 may be useful in differentiating primary skin tumours from metastatic adenocarcinoma. Note that staining is nuclear.

	normal epithelium	basal and suprabasal cells positive, spinous, granular and corneum layers negative1
	root sheaths	outer cells and hair bulb positive, inner root sheath and hair matrix negative1
	erector pili muscles	variable1
	sebaceous glands	gerrminative layer of and duct cells positive, mature sebocytes negative1
	eccrine glands	myoepithelial cells and basal cells positive1
	apocrine cells	myoepithelial cells and outer layer of ducts positive1
	cutaneous endothelial cells	negative1
	dermal mesenchymal cells, nerves, adipocytes, inflammatory cells	negative1

Benign adnexal tumours	trichoepitheliomas	9/9 (basal cells)1
	eccrine poromas	6/6 (cords of basal cells)1
	syringomas	3/3 (myoepithelial cells of ductal structures)1
	eccrine spiradenoma	1/1 (outer cells of the basaloid nodules)1
	papillary eccrine adenoma	1/1 (outer cells)1
Malignant adnexal tumours	eccrine adenocarcinomas	2/21
	hidradenocarcinoma	1/11
	microcystic adnexal carcinomas	4/41
	tricholemmal carcinomas	2/21
	mucinous sweat gland carcinoma	1/11
Adenocarcinomas metastatic to skin	breast	0/12(focal cytoplasmic staining in 3 cases)1
Adenocarcinomas metastatic to skin	gastrointestinal tract	0/21
Non-squamous carcinomas at various sites	lung adenocarcinoma	5/123
	lung small cell carcinoma	2/93
	stomach	2/133
	colon	1/133
	pancreas	2/73
	hepatocellular	1/93
	biliary	1/53
	renal	1/133
	breast	3/283
	ovary	2/153
	prostate	0/83
	embryonal	0/93
	mesothelioma	0/143
	total	20/1413
	urothelial	14/203
Squamous carcinomas at various sites	head & neck	24/32
	oesophagus	8/8
	cervix uteri	13/15
	anal canal	2/3
	lungs	12/15
	Total	59/733

References

1Ivan D, Hafeez Diwan A,Prieto VG Expression of p63 in primary cutaneous adnexal neoplasms and adenocarcinoma metastatic to the skin. Mod Pathol 2005; 18:137-42

2Reis-Filho JS, Simpson PT, Martins A, Preto A, Gartner F,Schmitt FC Distribution of p63, cytokeratins 5/6 and cytokeratin 14 in 51 normal and 400 neoplastic human tissue samples using TARP-4 multi-tumor tissue microarray. Virchows Arch 2003; 443:122-32

3Kaufmann, O., E. Fietze, et al. (2001). "Value of p63 and cytokeratin 5/6 as immunohistochemical markers for the differential diagnosis of poorly differentiated and undifferentiated carcinomas." Am J Clin Pathol 116(6): 823-30.

This page last revised 7.2.2005.