The use of MN/CA9 gene expression in identifying malignant solid renal tumors.
OBJECTIVE
Small solid renal tumors are increasingly encountered. It is important to determine the malignancy of solid renal tumors for the choice of treatment. MN/CA9 is expressed in malignant renal cells but absent in normal cells. MN/CA9 is one of the most powerful gene markers available for RCC. The objective of this pilot study is to utilize MN/CA9 gene expression in FNA biopsy to determine the malignancy of imaging-indeterminate solid renal tumors.


METHODS
A total of 35 patients with an imaging-indeterminate solid renal mass entered into this study. The molecular protocol consisted of a rapid column extraction of RNA and one-step RT-PCR for the detection of MN/CA9 gene expression. The preoperative molecular diagnosis was compared with postoperative pathology.


RESULTS
There were 28 RCCs (19 clear cell carcinomas, 7 papillary carcinomas and 2 chromophobe carcinomas) and 7 benign tumors proved by postoperative pathology. The overall sensitivity and specificity for MN/CA9 were respectively 68% and 100%. MN/CA9 was positive in 16/19 (84%) FNA biopsies of clear cell RCCs. No false positive appeared for MN/CA9 gene expression. Moreover, MN/CA9 gene expression was positive in 8/13 (62%) of false negative or suspect cytology.


CONCLUSIONS
Detection of MN/CA9 gene expression in FNA biopsy is possible. Its detection can be helpful in identifying the malignancy among renal tumors.
Li
Guorong
G
Department of Urology, North Hospital, CHU of Saint-Etienne, France. grli2001@yahoo.fr
Cuilleron
Muriel
M
Cottier
Michèle
M
Gentil-Perret
Anne
A
Lambert
Claude
C
Genin
Christian
C
Tostain
Jacques
J
D018262:Adenocarcinoma, Clear Cell / Q000737:chemistry / Q000473:pathology; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000235:genetics; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D001706:Biopsy; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases / Q000032:analysis* / Q000235:genetics; D002291:Carcinoma, Papillary / Q000737:chemistry / Q000473:pathology; D002292:Carcinoma, Renal Cell / Q000737:chemistry / Q000473:pathology; D003584:Cytological Techniques; D005189:False Positive Reactions; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020022:Genetic Predisposition to Disease; D006801:Humans; D007680:Kidney Neoplasms / Q000737:chemistry* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012334:RNA, Neoplasm / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D012334:RNA, Neoplasm; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases