title: KI-67 AND hTERT expression can aid in the distinction between malignant and benign pheochromocytoma and paraganglioma.
abstract: The clinical and histopathological distinction between benign and malignant pheochromocytomas and paragangliomas is difficult, and reliable diagnostic markers are lacking. Here we have evaluated the prognostic value of human telomerase reverse transcriptase (hTERT) gene expression detected by reverse transcription PCR (RT-PCR); telomerase activity (TA) measured by TRAP (telomeric repeat amplification protocol) assay; immunohistochemical staining for Ki-67/MIB-1; and the mRNA expression of matrix metalloproteinase (MMP)-2 and EMMPRIN (extracellular matrix metalloproteinase inducer) analyzed by in situ hybridization in 32 primary pheochromocytomas or abdominal paragangliomas. hTERT was expressed in 7/11 malignant tumors (defined as presence of metastasis and/or extensive local invasion) as compared with in 2/21 benign tumors. All of the benign tumors showed <1% proliferative activity, as measured by Ki-67/MIB-1 staining. In all three patients with malignant tumors who developed metastases and/or invasive local recurrence during follow-up, the tumors were positive for either hTERT expression or Ki-67/MIB-1 immunoreactivity. TA was not a significant discriminator between benign and malignant tumors, and the value of EMMPRIN and MMP-2 as predictive markers was limited. In conclusion, the findings imply that the combined use of Ki-67/MIB-1 and hTERT, in addition to histopathology, provides a highly specific tool to identify benign pheochromocytoma and abdominal paraganglioma cases that are not at risk of developing recurrent or metastatic disease.
authors.affiliation: Department of Surgery, Karolinska Hospital, Stockholm, Sweden. elisabeth.edstrom.elder@kirurgi.ki.se
authors.forename: E Edström
authors.initials: EE
authors.lastname: Elder
authors.forename: D
authors.initials: D
authors.lastname: Xu
authors.forename: A
authors.initials: A
authors.lastname: Höög
authors.forename: U
authors.initials: U
authors.lastname: Enberg
authors.forename: M
authors.initials: M
authors.lastname: Hou
authors.forename: P
authors.initials: P
authors.lastname: Pisa
authors.forename: A
authors.initials: A
authors.lastname: Gruber
authors.forename: C
authors.initials: C
authors.lastname: Larsson
authors.forename: M
authors.initials: M
authors.lastname: Bäckdahl
mesh_terms: D000008:Abdominal Neoplasms / Q000378:metabolism / Q000473:pathology*; D000293:Adolescent; D000310:Adrenal Gland Neoplasms / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000368:Aged; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D051926:Basigin; D014408:Biomarkers, Tumor / Q000378:metabolism; D004268:DNA-Binding Proteins; D003937:Diagnosis, Differential; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010235:Paraganglioma / Q000378:metabolism / Q000473:pathology*; D010673:Pheochromocytoma / Q000378:metabolism / Q000473:pathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000096:biosynthesis* / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D000951:Antigens, Neoplasm; C497886:BSG protein, human; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D019394:Ki-67 Antigen; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D051926:Basigin; D019098:Telomerase; D020778:Matrix Metalloproteinase 2