Immunohistochemical markers of the hypoxic response can identify malignancy in phaeochromocytomas and paragangliomas and optimize the detection of tumours with VHL germline mutations

Br J Cancer. 2013 Feb 5;108(2):429-37. doi: 10.1038/bjc.2012.538. Epub 2012 Dec 20.

Abstract

Background: There are no reliable markers of malignancy in phaeochromocytomas (PCC) and paragangliomas (PGL). We investigated the relevance of the mammalian target of rapamycin (mTOR)/AKT and hypoxic pathways as novel immunohistochemical markers of malignancy.

Methods: Tissue microarray blocks were constructed with a total of 100 tumours (10 metastatic) and 20 normal adrenomedullary samples. Sections were immunostained for hypoxia-inducible factor 1α (Hif-1α), vascular endothelial growth factor A (VEGF-A), mTOR, carbonic anhydrase IX (CaIX) and AKT. The predictive performance of these markers was studied using univariate, multivariate and receiver operating characteristic analyses.

Results: In all, 100 consecutive patients, 64% PCC, 29% familial with a median tumour size of 4.7 cm (range 1-14) were included. Univariate analyses showed Hif-1α overexpression, tumour necrosis, size >5 cm, capsular and vascular invasion to be predictors of metastasis. In multivariate analysis, Hif-1α, necrosis and vascular invasion remained as independent predictors of metastasis. Hif-1α was the most discriminatory biomarker for the presence of metastatic diffusion. Strong membranous CaIX expression was seen in von Hippel-Lindau (VHL) PCC as opposed to other subtypes.

Conclusion: Lack of vascular invasion, tumour necrosis and low Hif-1α expression identify tumours with lower risk of malignancy. We propose membranous CaIX expression as a potential marker for VHL disease in patients presenting with PCC.

MeSH terms

  • Adrenal Gland Neoplasms / diagnosis
  • Adrenal Gland Neoplasms / genetics
  • Adrenal Gland Neoplasms / immunology
  • Adult
  • Antigens, Neoplasm / analysis*
  • Antigens, Neoplasm / immunology
  • Biomarkers, Tumor / analysis
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / immunology
  • Carbonic Anhydrase IX
  • Carbonic Anhydrases / analysis*
  • Carbonic Anhydrases / immunology
  • Cell Hypoxia
  • Female
  • Germ-Line Mutation
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / analysis*
  • Hypoxia-Inducible Factor 1, alpha Subunit / immunology
  • Immunohistochemistry
  • Male
  • Neoplasm Metastasis
  • Paraganglioma / chemistry*
  • Paraganglioma / diagnosis
  • Paraganglioma / genetics*
  • Pheochromocytoma / chemistry*
  • Pheochromocytoma / diagnosis
  • Pheochromocytoma / genetics*
  • Proto-Oncogene Proteins c-akt / analysis
  • Proto-Oncogene Proteins c-akt / immunology
  • TOR Serine-Threonine Kinases / analysis
  • TOR Serine-Threonine Kinases / immunology
  • Tissue Array Analysis
  • Vascular Endothelial Growth Factor A / analysis
  • Vascular Endothelial Growth Factor A / immunology
  • Von Hippel-Lindau Tumor Suppressor Protein / genetics*
  • von Hippel-Lindau Disease / diagnosis
  • von Hippel-Lindau Disease / genetics

Substances

  • Antigens, Neoplasm
  • Biomarkers, Tumor
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Vascular Endothelial Growth Factor A
  • Von Hippel-Lindau Tumor Suppressor Protein
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • CA9 protein, human
  • Carbonic Anhydrase IX
  • Carbonic Anhydrases