Gastric carcinoma does not respond satisfactorily to new immune substance

In one of the world's largest patient studies ever conducted on advanced gastric cancer, an initially promising antibody therapy did not show satisfactory efficacy. The active substance "cetuximab", which is active in other types of cancer, is therefore not a beacon of hope for combined chemotherapy and antibody treatment for gastric cancer.

The need for improved treatment is particularly high in patients with advanced gastric cancer. At this stage, the tumour is very aggressive, has spread and is no longer operable. Patients have a short survival time and a high symptom burden. Until now, treatment has usually involved many months of chemotherapy to alleviate symptoms and prolong survival.

A good 900 patients were involved in the clinical trial conducted in Europe, Asia and Latin America under the leadership of Leipzig University medical specialist Prof Florian Lordick. All of them received conventional chemotherapy, half of them were also treated with a biological agent. The antibody-immune substance "cetuximab" was expected to improve the efficacy of chemotherapy because correspondingly good indications of efficacy had been observed in preliminary studies. The antibody is directed against a tumour protein, a so-called growth receptor with the technical abbreviation EGFR. In colon tumours and squamous cell carcinoma of the head and neck, the active substance is effective and is already in clinical use. In gastric tumours, however, the drug did not show sufficient efficacy, as the study, which has now been published in the renowned journal "The Lancet Oncology", has shown.

"As is often the case in oncology, when you carry out an in-depth review on a large group of patients and at many cancer centres, it unfortunately turned out that a well-founded approach could not be confirmed," says Prof. Lordick, summarising the results of the study. The active substance will therefore not be available for clinical use in gastric carcinoma in the future. "With regard to our patients with gastric cancer, the result is a setback because we were unable to make the therapy more effective on a broad basis," says Prof Florian Lordick, Head of the University Cancer Centre Leipzig (UCCL). "Nevertheless, it is a step forward in terms of our knowledge of tumour diseases. Because we also learn a lot from negative results and it is only through these findings that follow-up steps can be planned and cancer treatment improved in the long term. It has been shown that an even more specific approach must be taken to cancer. Tumours must be divided into smaller, biologically defined groups so that targeted agents have a chance beyond the statistical mean."

Because tumour material and blood samples were collected from all study participants, a valuable collection for further analyses has been created. "We will now look for biological characteristics in the individual tumours and their influence on the mode of action of the antibody and the chemotherapy," says the cancer researcher. "Then we may be able to identify subgroups that benefit from antibody therapy." These days, Prof Lordick has been given the go-ahead for the blood samples from this study to be made available to Leipzig University Medicine for further investigations.
Link to the specialist publication: http://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(13)70102-5/fulltext

doi:10.1016/S1470-2045(13)70102-5

Further information:
Prof. Dr Florian Lordick
University Cancer Centre Leipzig (UCCL) at the University Hospital
Phone: +49 341 97 12560
Email: Direktion.UCCL@medizin.uni-leipzig.de
Web: http://www.krebszentrum-leipzig.de

Source: Leipzig University press release 106/2013 from 18 April 2013