Ha-ras codon 12 mutation in papillary tumors of the urinary-bladder - a retrospective study

This report concerns the retrospective examination of low grade, low stage (Ta/T1) bladder tumors for the Ha-ras codon 12 G-->T mutation. The patients studied had a minimum of 5 years follow-up and were grouped into 3 categories: (i) patients with no recurring tumors, (ii) patients with recurring Ta/T1 tumors and (iii) patients who subsequently developed high grade, high stage tumors. A heminested, non-isotopic, allele-specific polymerase chain reaction (PCR) amplification assay was used. The codon 12 G-->T mutation was found in 10/27 specimens from patients with non-recurring Ta/T1 tumors; in 11/27 initial and 12/23 recurring Ta/T1 tumors, and in 5/8 initial Ta/T1 lesions and 8/12 subsequently developed high grade/stage tumors. Although there was no correlation between disease recurrence and mutation, these results indicate that a relatively large proportion of patients with Ta/T1 tumors of the bladder have cells with the Ha-ras codon 12 G-->T substitution.