[1591] Immunoprofile of Pediatric Liver Tumors.

Katharine Van Patten, Marie Robert, Dhanpat Jain, Kisha Mitchell. Yale University, New Haven

Background: Liver tumors are rare in children and include hepatoblastomas (HB), hepatocellular carcinoma (HCC) and focal nodular hyperplasia (FNH). Little published data exists on immunohistochemical profiles of these tumors in children. We examined the expression of a panel of markers that have been shown to be useful in evaluating liver tumors in adults.
Design: We identified available tissue from 4 needle biopsies and 13 resections of liver masses in children (< 18 years) between 1985 and 2010 at our institution. These were stained with reticulin, CD34, AFP, pCEA, HepPar, GP3, HSP70 and Arg-1. The staining pattern of each marker was recorded as negative (no staining), patchy (<30% of tumor cells), moderate (30-60%) and diffuse (>60%), while intensity was scored as weak, moderate or strong, (Arg-1 and GPC3). AFP and HSP-70 were scored by absolute percent positive cells.
Results: Sixteen cases, 10 males and 6 females, (HB=7, HCC=6, FLC =2, FNH=3) from patients of age range 4 months to 16 years were examined. Of the carcinomas, 2 were of fibrolamellar type (FHCC) with the typical large tumor cells with cytoplasmic pale bodies within abundant fibrous stroma. Of the HBs 4 were epithelial and 3 epithelial/mesenchymal. The results are shown in Table 1.

Staining profile of pediatric liver tumors

Lesion	Cd34	LR	%AFP	Hep	Arg	%HSP	GP3
CHCC	P	I	60	D	D/S	10	M/M
CHCC	P	I	40	D	D/S	0	P/M
CHCC	P	I	1	D	D/M	10	D/M
CHCC	D	M	1	P	D/S	2	D/S
FHCC	D	I	0	M	D/W	0	N
FHCC	D	I	0	D	D/W	0	N
HB	D	P	80	M	D/M	0	D/S
HB	M	D	50	M	D/S	1	D/S
HB	M	I	0	N	P/M	0	P/M
HB	D	I	10	M	M/S	70	D/S
HB	D	D	60	P	M/S	30	D/S
HB	D	D	20	M	M/S	0	D/S
HB	M	D	70	P	M/S	0	D/S
FNH	M	I	0	D	D/S	0	N
FNH	M	I	0	D	D/S	0	N
FNH	M	I	0	D	D/S	80*	N

N-negative, LR- lost reticulin, P-patchy, M-moderate, D-diffuse, S-strong, W-weak, *- nuclear only

Arg was a sensitive marker of hepatocytes, benign and malignant. Hepar was also a sensitive marker with less consistent staining in HB. PCEA is a poor marker of liver lineage in HB (positive in 1/7).
Conclusions: GPC3 distinquished benign from malignant hepatic lesions in this population of pediatric tumors. In contrast to adults, in pediatric HCC, CD34 and reticulin stains were not useful in this distinction. These findings provide further evidence of the utility of GPC3 staining in the diagnosis of hepatocellular tumors and is the first study to explore the use of this antibody in pediatric populations and also show the potential utility of HSP. This data also supports the distinct difference in immunoprofile between CHCC and FHCC.
Category: Liver & Pancreas

Tuesday, March 1, 2011 9:30 AM

Poster Session III # 264, Tuesday Morning