Prof. Dan Aderka, Head of the Gastrointestinal Cancer Service at Sheba, recently conducted research that brought an end to a long-standing controversy over the treatment regimen for Colorectal Cancer (CRC) patients. The study, as reported by the newspaper Israel Hayom, discovered that various combinations of chemotherapy and biological medicine directly affected the life expectancy of CRC patients, depending on the specific type of tumor.
The research results were published in the renowned The Lancet Oncology, one of the world’s most prestigious medical journals. Prof. Aderka conducted this research at Sheba’s Oncology Division in collaboration with international colleagues.
For the past decade, cancer experts have debated the treatment of approximately 35% of metastatic CRC patients – those who have tumors that contain receptors for EGFR (Epidermal Growth Factor Receptor). The main question was whether to first use Avastin and then Erbitux along with the chemotherapy treatment or to administer these medicines in the opposite sequence. Prior research had led to conflicting results.
Prof. Aderka’s study focused on patients with an incurable tumor, and they were classified into four groups according to the type of their CRC tumor. In one group, the administration of Avastin together with chemotherapy boosted life expectancy by an average of 21 months. In comparison, the use of Erbitux and chemotherapy increased life expectancy by an average of 40 months.
When the study was applied to a group of patients with a different type of CRC tumor, Avastin was shown to increase life expectancy by 22 months on average, and Erbitux was not as effective – increasing life expectancy by an average of 11 months.
“The different results obtained with the same biological material for the same type of tumor stemmed from the simultaneous combination of various chemotherapy drugs: in one study, the chemotherapy worked together with the biological drugs against the tumor, while in the other the chemical stimulated the secretion of substances that neutralized biological activity, which reduced its effectiveness,” explained Prof. Aderka.
The results of this study conducted at Sheba introduce an entirely new perspective into the medical view of the most effective methods of treatment delivery for patients with CRC tumors.
“For years, we did not know how to maximize the potential of the drugs, and we did not care with which of the two biological drugs we started the treatment. We thought that applying one treatment was suitable for all patients,” Prof. Aderka said.
“If the right combination of drugs was applied, the patient’s life expectancy would be extended. Whereas if another combination had been used – their life expectancy would not be extended. In one case, we even observed that a combination of a biological drug and chemotherapy in one of the tumor types reduces the effectiveness of the biological drug and not the other way around, as we have thought for years.”