GENETIC DETECTION OF LYMPH-NODE MICROMETASTASES IN PATIENTS WITH COLORECTAL-CANCER

Background Undetected micrometastases represent the single most import ant cause of treatment failure in patients undergoing putatively curat ive resection for colorectal cancer because current staging techniques are unable to identify patients with minimal residual disease. Method s A highly sensitive reverse transcription-polymerase chain reaction t echnique has been used to amplify tissue-specific messenger RNA from l ymph nodes classified as tumour-free using both conventional histopath ology and immunohistochemistry, Results Four of 15 patients were resta ged after genetic diagnosis of lymph node micrometastases, while in a further two additional positive nodes were detected. Conclusion Sensit ive genetic techniques that detect minimal residual disease merit furt her study, particularly as there is evidence that patients may benefit from adjuvant chemotherapy.