title: Quantification of cytokeratin 20, carcinoembryonic antigen and guanylyl cyclase C mRNA levels in lymph nodes may not predict treatment failure in colorectal cancer patients.
abstract: Conventional histopathologic staging of primary colorectal cancers does not allow accurate prognostic stratification within a given tumour stage. Therefore, PCR-based assays are increasingly used to try to predict more accurately the likelihood of disease progression for the individual patient. Real-time reverse transcription PCR (RT-PCR) assays were used to detect and quantitate cytokeratin 20 (ck20), carcinoembryonic antigen (CEA) and guanylyl cyclase C (GCC) mRNA in 149 lymph nodes (LN) from 17 patients with benign disease and 302 LN from 42 patients with colorectal cancer who had curative (R0) resections. None of the markers were specific, with ck20, CEA and GCC mRNA detected in 47%, 89% and 13% of 149 LN, respectively, from patients with benign disease. The sensitivity of all 3 markers was very high, with mRNA detected in 93%, 100% and 97% of 30 histologically involved LN, respectively. There was significant overlap in the mRNA levels of all 3 markers between histologically involved and uninvolved LN. There was no association between mRNA levels and distant recurrence (median follow-up: 3.94 years, range 3.35-5.12). We conclude that the use of molecular techniques to detect occult disease in LN may suffer from the same limitations as conventional methods. Instead, accurate prognostic stratification requires careful assessment of the likely metastatic potential of the primary cancer.
authors.affiliation: Centre for Academic Surgery, Barts and the London Queen Mary's School of Medicine and Dentistry, London, United Kingdom. s.a.bustin@qmul.ac.uk
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Bustin
authors.forename: Shahab
authors.initials: S
authors.lastname: Siddiqi
authors.forename: Shafi
authors.initials: S
authors.lastname: Ahmed
authors.forename: Rebecca
authors.initials: R
authors.lastname: Hands
authors.forename: Sina
authors.initials: S
authors.lastname: Dorudi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D002272:Carcinoembryonic Antigen / Q000235:genetics*; D016022:Case-Control Studies; D002454:Cell Differentiation; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D005260:Female; D006162:Guanylate Cyclase / Q000235:genetics*; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics*; D053554:Keratin-20; D008198:Lymph Nodes / Q000737:chemistry*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics / Q000473:pathology; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D017211:Treatment Failure
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; D053554:Keratin-20; D012333:RNA, Messenger; D006162:Guanylate Cyclase