DiagnoCure Inc’s Previstage GCC Colorectal Cancer Staging Test will be featured at the annual meeting of the American Society of Colon and Rectal Surgeons (ASCRS) to be held in Vancouver, Canada, from May 15 to 17, 2011. In parallel to this key medical conference, the results of a recent study on the GCC test, presented earlier at ASCO GI 2011, have now been published in the peer‐reviewed journal Annals of Surgical Oncology (May 2011), with Dr. Daniel J. Sargent, professor of biostatistics and oncology at Mayo Clinic as lead author and Principal Investigator of the study.
The published article reported the results of the first phase of an on-going clinical study, which was conducted on lymph nodes of 241 stage II colon cancer patients. These patients had not been treated with adjuvant chemotherapy mainly because their lymph nodes appeared cancer-free by examination under the microscope, yet 12% of them had a disease recurrence or cancer-related death afterwards. The Previstage GCC test uses a technology that is 100,000 times more sensitive and which can then detect cancer cells in the lymph nodes that have escaped detection by the current microscopic examination method.
In order to establish a risk of recurrence (prognosis) for the stage II patients, the study focused on the positive lymph node (LN) ratio, defined as the number of nodes in which cancer cells were identified with the Previstage GCC test, divided by the total number of nodes examined. This LN ratio approach was able to significantly predict higher recurrence risk for 84 patients (35%). In fact, the estimated recurrence rates at five years after surgery were 27% for patients with a LN ratio equal to or higher than 1/10 (high-risk group), and 10% for patients with a LN ratio under 1/10 (low-risk group).
In addition, in a subset of 181 patients with traditionally favorable prognostic factors, that is, an invasive T3 tumor and 12 or more lymph nodes examined, the Previstage GCC test classified 1/3 of patients with a high risk of recurrence at five years, and 2/3 of patients at low risk of recurrence. In this subset, the high-risk group had a 6 times greater likelihood to recur than the low risk group (27% vs 4%).
Previstage GCC is currently the only colorectal cancer staging test on the market that provides prognostic information based on the tumor burden measured at the molecular level in the lymph nodes. Tumor burden in the lymph nodes is more and more recognized by treating physicians as a key prognostic factor to determine the risk of recurrence of cancer patients, and hence, to determine which patients might benefit most from adjuvant chemotherapy and which could be safely managed without chemotherapy.
Source: DiagnoCure
