Stable disease in advanced colorectal cancer: therapeutic implications.

Colorectal cancer is one of the most common neoplasms in Western Countries and ranks second as a cause of death due to cancer. The overall mortality at 5 years is about 40%. Patients with resectable metastatic disease can be cured, but for those who cannot, treatment is purely palliative, and overall survival (OS) is from approximately 7 to 24 months. Infusional regimen with modulated 5Fluorouracil (5FU) gives an objective response rate (RR) of up to 30-40%. The addition of CPT11 or oxaliplatin to 5FU improves RR, time to progression (TTP) and OS with a stabilization of disease (SD) in 40-70% of cases and 20-40%, respectively. The concurrent utilization of selective biological agents as growth factor receptors acting at a molecular level and influencing the processes of tumor formation and growth, increases tumor cell apoptosis and inhibits tumor growth; as a result, the tumor regresses or is inhibited, with consequently prolonged OS and TTP. This paper examines the problem related to the treatment of metastatic colorectal cancer with SD. Current doubts regarding the continuation of one treatment until disease progression (PD) with a risk of toxicity, whether or not to use a less toxic "maintenance" therapy after a fairly aggressive "induction" therapy in "stabilized" responders, or whether to stop the treatment in the presence of a SD confirmed after at least two consecutive evaluations, are present.