Cancer 'Hijacks' Brain, say’s researchers

                                                                                                               Dr. Divyanshu Sengar and Mukesh Sharma

Doctors have long associated advanced stage cancer patients' tendency to withdraw from life as a psychological response to physical deterioration.

Now, a study published in Science magazine by US researchers says cancer "hijacks" a part of the brain that controls motivation and that this withdrawal from life is not merely from physical decline, but fallout of the disease itself.

Oncologists in Kolkata believe this could be true in most cases since a large number of patients fail to cling to their favourite activities ordaily routines despite being physically fit to carry on with them. They also pointed out that Bengal has a significantly large number of cancer patients suffering from depression. The symptom is part of a syndrome called "cachexia", which affects 80% of latestage cancer patients.

This finding could be an eye opener and lead to major changes in cancer therapy, said Manipal Hospital oncologist Dr Subir Ganguly. "A clinical option to treat depression could help many cancer patients respond to treatment better and comply with prescribed treatment," Dr Ganguly said, adding, "This will improve survival rate and treatment outcomes. But other than the clinical aspect, there are psychological and emotional reasons that trigger depression, which is why we have many giving up on life.

For instance, a cancer patient with disabilities is bound to be more frequently demotivated than others. Then, some financial issues and constraints act as major triggers for depression. Many lack family support and caregivers. These patients will still require a support system." Dr Diptendra Sarkar, professor of oncology at IPGMER, said: "We frequently come across patients who turn apathetic towards life despite efforts to motivate them.

This happens even to those who show considerable improvement and have several years to live. This study reveals neurotransmitters are responsible for this, and the condition is clinically treatable. This will benefit millions of cancer patients and add to the number of survivors. More importantly, their quality of life will also improve." Using brain mapping techniques on mice, researchers identified an area in the brain called postrema, which acts as the brain's inflammation detector.

As a tumour grows, it releases cytokines molecules that trigger inflammation into the blood stream. Postrema lacks the blood brain barrier, allowing it to sample the circulating inflammatory signals. Once this happen, postrema triggers a neural cascade across several brain regions, eventually suppressing dopamine release in the brain's motivation centre, the nucleus accumbens. The research says that dopamine is wrongly identified as the brain's "pleasure chemical" but is actually associated with a willingness to put in effort for gain.

Writer: Dr. Divyanshu Sengar, Medical Officer of Pyare Lal Sharma, District Hospital, Meerut.