How chemotherapy impacts the body

Current standard cancer treatments, such as chemotherapy and radiotherapy, can have lasting effects on the body. Chemotherapy for example is associated with many side effects, such as nausea and anaemia, due to the impact of the toxins on healthy tissue as well as the tumour.

Neoadjuvant therapy, whereby therapies are administered before the main treatment, to help reduce the size of a tumor or kill cancer cells that have spread, has previously been suggested to contribute to changes in the composition of a patient’s body. This includes reduction in muscle mass (or ‘sarcopenia’) which is a natural result of aging, but in those with cancer it can lead to some post-operative complications and other diseases further down the line.

A new study from Mr Nick Maynard, Oxford University Hospitals Trust, has assessed the changes in muscle mass in gastro-oesophageal cancer patients, to better understand the long-lasting impact therapies have on the body and if it can be used to predict the risk of post-op complications. From a sample of 199 patients, they observed a decrease in skeletal mass in all individuals, with 91 participants losing more than 5% of their original skeletal mass. Those with a high rate of muscle mass depletion were generally male and significantly older, i.e. over the age of 67 years old.

50% of patients in the study experienced post-operative complications, such as pneumonia, with 13% having severe complications. However, Nick and the team observed that this was not related to the patient’s loss of skeletal mass.

Fortunately, this means that patients undergoing surgery for oesophageal cancer with large reductions in muscle mass are not necessarily at an increased risk of post-operative complications. Whilst these results do not produce any new method for predicting post-op complications, as sarcopenia did not determine the frequency of post-op complications in the sampled patients, they provide a deeper understanding of how neoadjuvant therapies can impact the body. This is important as post-operative loss of muscle mass has been previously associated with a lower survival rate for oesophageal cancer patients, so this will help to inform clinicians which patients may need to be more closely monitored.