Monoclonal antibodies in cancer therapy - New perspectives after the colorectal carcinoma trial

A new perspective for monoclonal antibodies (mAbs) is their use in patients presenting with minimal cancer burden or micrometastatic disease, i.e. in secondary prevention of metastatic cancer disease. The first proof of efficacy of a mAb in minimal residual disease has recently been published with mAb 17-1A in patients with colorectal cancer stage III after complete resection of the primary tumour. After a median follow-up of 5 years, antibody therapy reduced overall death rate by 30% and decreased the recurrence rate by 27%. This result is similar to the benefit obtained with (radio)chemotherapy trials, however, with notably less toxicity. Because the mechanisms of action of the different treatment modalities may be complementary in the control of tumour growth, more rationally designed clinical trials that combine conventional chemo-, hormonal or radiation therapy with immuno- or biotherapy need to be initiated. Also, with the more widespread use of prognostic parameters and increased abilities to characterise isolated tumour cells left behind in the patient, future therapy may eventually become more individualised and less consensus-oriented, thus leading to an improved risk: benefit ratio for the patient and reduced cost to society.