title: Real-time RT-PCR detection of CK19, CK7 and MUC1 mRNA for diagnosis of lymph node micrometastases in non small cell lung carcinoma.
abstract: Metastatic lymph nodes (LNs) are the major prognostic factor in resected non small cell lung carcinoma (NSCLC). However, almost 50% of pN0 patients relapse, suggesting metastatic cells undetected by current staging procedures. A combination of markers [cytokeratins 19 and 7 (CK19, CK7) and mucin type 1 (MUC1) mRNAs] was therefore evaluated by real-time RT-PCR in order to detect occult cancer cells. Forty-three NSCLC tumor samples, 4 micrometastatic, 6 metastatic and 84 histologically negative mediastinal LNs from 19 patients with NSCLC were evaluated as well as blood mononuclear cells from 29 healthy volunteers and 17 benign LNs. When tested on cell lines, RT-PCR was particularly efficient for evaluation of CK19, CK7 and MUC1 mRNA expression. All tumor samples were positive for at least 1 marker and 74% of samples were positive for all 3 markers. CK7 and CK19 mRNA were not detected in benign LN and blood cells from healthy donors in contrast with MUC1 mRNA. Only CK7 and CK19 mRNA were therefore used for evaluation of mediastinal LNs: the 6 histologically metastatic and the 4 micrometastatic LNs were positive for at least one marker. Among the 84 histologically negative LNs, 6 (7%) were positive for at least one marker, potentially changing the stage of 2 out of 19 patients. In conclusion, in our feasibility study, parallel molecular detection of CK19 and CK7 mRNA can be considered a specific diagnostic tool for the assessment of microscopic lymphatic spread. Its prognostic impact remains to be evaluated in a prospective study.
authors.affiliation: Histologie-Biologie Tumorale, UPRES EA 3499, Université Paris 6, Hôpital Tenon, Paris, France. pierre.saintigny@avc.ap-hop-paris.fr
authors.forename: Pierre
authors.initials: P
authors.lastname: Saintigny
authors.forename: Séverine
authors.initials: S
authors.lastname: Coulon
authors.forename: Marianne
authors.initials: M
authors.lastname: Kambouchner
authors.forename: Sylvie
authors.initials: S
authors.lastname: Ricci
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Martinot
authors.forename: Claire
authors.initials: C
authors.lastname: Danel
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Breau
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Bernaudin
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000235:genetics / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7; D007633:Keratins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics*; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; C507497:KRT7 protein, human; D053552:Keratin-7; D018396:Mucin-1; D012333:RNA, Messenger; D007633:Keratins