Blood Test Predicts Recurrence in Early Stage Breast Cancer
By LabMedica International staff writers
Posted on 20 Jun 2012
A blood test for circulating tumor cells (CTCs) in early stage breast-cancer patients may predict their chance for recurrence and survival. Posted on 20 Jun 2012
The presence of CTCs in the blood correlates with a poor prognosis once breast cancer has metastasized to other parts of the body, but early detection of CTCs may have a predictive value in the early stages of the disease.
Scientists at the MD Anderson Cancer Center (Houston, TX, USA) collected CTCs from blood and bone samples of 302 breast cancer patients whose mean age was 54, and whose cancer was in Stage I, Stage II and Stage III. All patients were being treated at the Center, and none had undergone chemotherapy before giving the samples. Patients with cancer in more than one breast, or who had another cancer within five years of their breast cancer diagnosis, were not included.
The team used a system called CellSearch (Veridex; Raritan, NJ, USA) to detect and measure the CTCs. They then correlated the results with tumor characteristics, such as size and grade; hormone status for estrogen and progesterone receptors and human epidural growth factor receptor 2 (HER2), and the extent of lymph node involvement. They followed the patients for a median period of 35 months, and carried out statistical tests to find any links between CTC measurements and progression-free and overall survival.
The results of the study showed that detection of one or more CTCs predicted both decreased progression-free survival, or early disease recurrence, and overall survival.
There was a breast cancer-relapse rate of 15% in patients who had at least one CTC, compared with a relapse rate of 3% among those who had no detected CTCs. The more CTCs detected, the lower the progression-free survival and overall survival. After two years of follow-up, the progression-free survival in patients with no CTCs was 98%. This can be compared with the 87% the progression-free survival for patients with one or more CTCs, 79% for those with two or more CTCs, and 69% for those with three or more CTCs.
Anthony Lucci, MD, the senior author and professor of surgical oncology, said, "The presence of one or more circulating tumor cells predicted early recurrence and decreased overall survival in chemonaive patients with nonmetastatic breast cancer. These results suggest that assessment of circulating tumor cells might provide important prognostic information in these patients." The study was published on June 6, 2012, in the journal the Lancet Oncology.
Related Links:
MD Anderson Cancer Center
Veridex