Removing the ‘sword of Damocles’
MONTCLAIR, N.J.—Known for its innovative technologies in predicting systemic mestastasis in cancer cases, life-sciences company MetaStat Inc. has announced positive results from its MetaSite Breast test, published online in the Journal of the National Cancer Institute. The study successfully indicated the test could accurately predict the probability of which breast cancer patients need chemotherapy—and which patients do not.
Systemic metastasis—cancer that spreads from a primary tumor through the bloodstream to other areas of the body—is responsible for about 90 percent of all solid tumor cancer-related deaths, according to Dr. Oscar Bronsther, MetaStat CEO.
Being able to predict the probability of systemic metastasis allows doctors to better customize cancer treatment decisions by identifying patients with a high-risk of systemic metastasis who need aggressive therapy, and sparing patients with a low-risk of systemic metastasis from the harmful side effects and expense of chemotherapy, Bronsther said.
“Some 240,000 women are newly diagnosed with breast cancer every year in America,” Bronsther tells DDNews. “Virtually all will have their tumors surgically removed. That is the first step in their journey. What comes after that is answering the question of whether there is a need for chemotherapy, traditionally used to prevent cancer from spreading through the rest of the body.”
“Because we lack a good (approved) cancer diagnostic, we lack the ability to effectively treat women with no progression or mestastasis at all,” he adds. “If we had a test right up front … that would tell a woman with breast cancer whether the risk of mestastasis was nearly zero. Then the sword of Damocles wouldn’t have to hang over her head for a decade.”
If oncologists had access to MetaSite Breast, its diagnostic ability could dramatically improve lives and give the future back to most breast cancer survivors, Bronsther says, because only 35 to 40 percent of all breast cancers will ever metastasize. Unfortunately, at present “almost 85 percent of women with newly diagnosed breast cancer are treated with chemotherapy. Yet, only a fraction of these patients can actually benefit from chemotherapy, because only a fraction of these tumors have the biological potential to spread through the bloodstream,” he notes.
A complete course of chemotherapy is extremely expensive and, more importantly, takes at least six months and is associated with significant morbidity and a small mortality, he says. Thus, “Having the ability to identify those patients whose tumors are unlikely to metastasize, we can therefore spare those patients the complications.”
The journal paper, titled “Tumor Microenvironment of Metastasis and Risk of Distant Metastasis of Breast Cancer,” states how the MetaSite Breast test, a diagnostic assay that quantifies the number of “tumor microenvironments of metastasis” (TMEM) in tumor specimens, showed a strong and statistically significant association with the risk of distant spread—or metastasis—for the most common type of breast cancer.
The study describes results from a case-control study that evaluated tumor samples from a subset of women in the Kaiser Permanente Northwest health plan that were diagnosed with invasive ductal carcinoma of the breast between 1980 and 2000, according to a MetaSite news release.
MetaSite testing was carried out on specimens from 259 women who later developed a distant metastasis (the cases), and on specimens from women who were alive and had not developed a distant metastasis (the controls). Controls were individually matched with cases so that women in each pair were the same age and diagnosed with breast cancer in the same year.
The test performed well at assessing metastasis risk for the study’s most populous cancer subgroup: women with estrogen receptor-positive (ER+)/ HER2/Neu-negative (HER2-) disease (i.e., their cancer cells possess estrogen receptors but lack HER2 protein).
Women with ER+/HER2- disease account for approximately 60 percent of all cases of breast cancer, according to the study. When women with this common type of breast cancer were divided into three groups based on their TMEM scores, the risk of distant metastasis turned out to be 2.7 times higher for women with tumors in the highest-scoring TMEM or MetaSite group compared with women with tumors in the lowest-scoring group.
The findings confirmed results from a smaller study of the test involving 30 pairs of biopsy specimens that was published in 2009.
For comparison, TMEM predictions were compared on the same tumor samples to predictions from the IHC4 test, a diagnostic that assesses risk of recurrence by measuring levels of several proteins (ER,PR, HER2 and Ki-67) involved in tumor cell proliferation and response to hormone therapy in breast tumor tissue, the journal study reported.
As for assessing metastatic risk in the study’s most common type of breast cancer (ER+/HER2-), “TMEM results were highly statistically significant, while IHC4 scores were borderline significant at best,” the study stated. “MetaStat believes this is due to its unique understanding of the mechanics and the function-based processes of tumor cell migration and entry into the bloodstream.”
MetaStat is currently developing a commercially viable version of the MetaSite Breast test with automated systems to facilitate rapid repeatable implementation in a high-throughput clinical lab setting, Bronsther says.
“We are thrilled to see additional positive validation of the MetaSite Breast test,” Bronsther stated in a news release. “We believe it confirms the path-breaking approach that our function-based diagnostics, based on the biology of the mena protein and its isoforms, provide an understanding in cancer metastasis.”
“We believe our suite of breast cancer diagnostic tests, comprised of MetaSite Breast and MenaCalc, will offer women and their oncologists highly prognostic and actionable information,” Bronsther continued. “These diagnostic tests aim to empower patients with the information they seek to create the most personal and appropriate approach to their unique tumors.”
MetaStat plans on commercializing its suite of breast cancer diagnostics in December 2015 or January 2016, based on CLIA and GLP certification. The company’s commercialization efforts will be headed by Heiner Dreissman, former president and CEO of Roche Molecular Systems.
The study was sponsored by MetaStat and led by researchers at Albert Einstein College of Medicine of Yeshiva University (Einstein), Montefiore Medical Center and the David H. Koch Institute for Integrative Cancer Research at the Massachusetts Institute of Technology. Lead author of the study was Dr. Thomas Rohan of Einstein.