Potential role of doppler perfusion index in selection of patients with colorectal cancer for adjuvant chemotherapy.

As yet there is no established method of accurately identifying patients with colorectal cancer who, despite undergoing apparently curative resection, are at high risk of recurrence. We assessed whether the doppler perfusion index (DPI; ratio of hepatic arterial to total liver blood flow) could be used to select patients who should receive adjuvant chemotherapy. We studied 120 patients undergoing curative surgery for colorectal cancer. DPI was measured before surgery with colour duplex doppler ultrasonography. A DPI value of at least 0.3 was defined as abnormal. All patients were followed up until death or for at least 5 years. At 5 years, patients with Dukes' stage A or B tumours (n=61) had recurrence-free survival of 57% and overall survival of 64%, compared with 39% and 42% for patients with Dukes' stage C tumours (n=59; p=0.016 and p=0.008, respectively). 47 patients had normal DPI values and 73 patients had abnormal values. Patients with normal DPI had recurrence-free survival of 89% and overall survival of 91%, compared with 22% and 29% for those with abnormal DPI values (both p<0.0001). DPI can be used to identify patients with colorectal cancer at high risk of recurrence who are in need of adjuvant treatment. However, further studies with larger numbers of patients are needed to confirm these findings.