By Alfred Nyakinda
A recent study indicates that immune therapy which stimulates the body’s immune system to fight cancerous tumours prior to undergoing surgery to remove them could significantly improve the chances of successful treatment.
Researchers from the Netherlands Cancer Institute (NKI) working in conjunction with other scientists have found benefits in the pre-surgical use of drugs that prevent cancer cells from releasing chemicals that suppress the immune system’s ability to attack them. The current standard practice only uses immunotherapy after surgery
“You can determine whether a patient responds to a certain drug, because you can see in the tumour material that is obtained during surgery whether the cancer cells have died”, says Christian Blank, NKI oncologist and researcher, “Also, the immune response induced by the immunotherapy is expected to be broader and therefore better.
“If the tumour is still present in the body, the immune system can learn to recognize the entire tumour with all its variations. The tumour may also be smaller and easier to remove after immunotherapy.”
The institute performs studies on immunotherapy prior to surgery, known as neoadjuvant treatment, among patients with different types of cancers, however the ones involving melanoma patients, those with skin cancer, are the most advanced.
Last year, the first phase of a three-phase clinical trial showed positive results alongside severe side effects among 20 melanoma patients in whom the cancerous growths had spread to the lymph nodes.
As a result, the scientists initiated a new study in the second phase, which used three different treatment schedules. This study, known as OpACIN-neo, examined the benefits of adjusted dosing schemes prior to surgery for 86 melanoma patients with growths, or metastases, in their lymph nodes.
Until recently the standard treatment for patients at this stage was surgical removal of the lymph nodes, which resulted in half the patients dying within five years as the cancer had already spread elsewhere in the body.
The results of the study, published in The Lancet Oncology, show that the treatment schedule that came out best causes much less severe side effects in 20 percent of the patients without effectiveness being reduced. Tumour reduction was seen in 23 of the 30 patients following this schedule and in 17 of them all cancer cells in the tumour were destroyed.
“With this study we confirm that neoadjuvant therapy is effective in many people, and we have now found a schedule with acceptable side effects”, says scientist Lisette Rozeman, first author of the publication.
After a follow-up period of on average eight months, none of the 65 patients who responded to either one of the three tested treatment schedules had relapsed. In nine out of the 21 who did not respond to the treatment, the disease did recur.
“The elegant aspect of the neoadjuvant approach is that the treatment result seems to be a good predictor for disease recurrence”, says Blank, “In the future it might even be possible to leave out surgery in patients who respond very well. Our studies also indicate that we might be able predict whether a patient will respond to this drug combination based on a small number of biomarkers.”
An extension study is currently investigating the optimal treatment schedule of the OpACIN-neo study in 100 patients with lymph node metastases. After its completion a larger study will be carried out in phase three to provide a definitive answer as to whether immunotherapy before or after surgery is better.
The researchers have set up an international association to further explore the development of neoadjuvant cancer immunotherapies. If future studies manage to improve the efficiency in identifying biological indicators to predict which combination of treatments a patient is likely to respond to, personalised cancer immunotherapy may come within reach.
