Protocol Title: Preoperative chemoradiotherapy and postoperative chemotherapy with capecitabine and oxaliplatin vs. capecitabine alone in locally advanced rectal cancer.
Study Chair: A/Professor Tim Price (Queen Elizabeth Hospital, Woodville SA)
Associate Oncology Program Manager: Chris Aiken
Trial Coordinator: Tina Van Tonder
Detailed information available on the Australian and New Zealand Clinical Trials Registry — PETACC6
Grants Awarded: Cancer Australia: $477,800 (2008). No funds were received by AGITG and no expenditure is included in the 2015 Income Statement.
PETACC-6 aims to that a treatment approach using a combination of capecitabine with oxaliplatin as chemotherapy in the pre- and post-operative treatment setting reduces the risk of recurrence or death in patients with locally advanced rectal cancer.
For locally advanced rectal cancer the 5-year overall survival rate remains below 70%. Even with improved rates of local control in rectal cancer; no recent improvements have been seen for distant recurrence or overall survival. It is thought that a combination chemotherapy regimen with capecitabine and oxaliplatin instead of a single agent regimen may improve overall outcome due to its potentially higher impact on micrometastases as is has already been proven to do so in stage III colon cancer.
Capecitabine was chosen as a substitute for IV 5-FU for all treatment arms of the study as it is already proven that 5-FU and capecitabine show similar results in complete response and disease survival rates for stage III CRC, however capecitabine offers reduced toxicity. The addition of oxaliplatin to capecitabine has shown to be efficacious and safe in phase II trials of preoperative chemoradiotherapy and in large phase III trials for stage II/III colon cancer.
The PETACC-6 study is an open-label, randomised, multi-national, two-arm phase III study. Eligible patients were randomised to one of two treatment arms. The control arm is capecitabine with radiotherapy before surgery, followed by capecitabine after surgery. The investigational arm is capecitabine with oxaliplatin and radiotherapy before surgery, followed by capecitabine and oxaliplatin after surgery.
The study’s objectives are to investigate whether the addition of oxaliplatin to preoperative fluoropyrimidine-based chemoradiation and postoperative fluoropyrimidine-based chemotherapy improves disease-free survival in locally advanced rectal cancer. Secondary objectives in this study are to compare the two treatment arms with respect to overall survival, pathological downstaging (ypT0-T2N0) rate, pathological complete remission rate, histopathological R0 resection rate, sphincter preservation rate, perioperative surgical complication rate, toxicity, loco-regional failure rate and distant metastases.
To view Study Schema click here.