New Treatment for Lung Neuroendocrine Tumors: Longer Survival with Everolimus

In recent years, considerable progress has been made in treating neuroendocrine tumors originating in the gastrointestinal system (stomach, intestines and pancreas), particularly the pancreas. Especially substantial advances have been achieved with targeted therapies, chemotherapy drugs that can be given as oral tablets, such as temozolomide and capecitabine, and radionuclide treatments such as lutetium. Compared with 10 years ago, these developments have made very positive contributions for patients in terms of both treatment response and survival. They have also changed our perspective as oncologists on treating these diseases.

However, the treatments now available had not produced the same positive effect in lung neuroendocrine tumors to the desired extent. The limited contribution of targeted therapies, chemotherapy and other treatments has always left gaps in our minds regarding treatment strategy. However, the study called RADIANT-4, presented at the 2015 ECC European Cancer Congress, reassured us all. Lung neuroendocrine tumors were also included in this study.

The study evaluated a total of 302 patients with progressive, well-differentiated lung and gastrointestinal neuroendocrine tumors. Of these patients, 90 had lung neuroendocrine tumors. The research found that the drug containing everolimus, used as a targeted treatment for both kidney cancer and gastrointestinal neuroendocrine tumors, also significantly prolonged the duration of treatment response in lung neuroendocrine tumors. Progression-free survival was 11 months in the group receiving everolimus, compared with 3,9 months in patients not receiving the drug. This produced a statistically highly significant result that would surprise and satisfy the scientific community.

The study results showed that nearly % 36 of patients lived longer, which is extremely significant. For the first time, a positive development in targeted therapy for lung neuroendocrine tumors has been recorded. This appears likely to change our routine practice rapidly. With the publication of the final study results and demonstration of its survival advantage, a new change in the treatment of lung cancer neuroendocrine tumors appears likely worldwide. This is welcome news for our patients.

Further Reading: How Does Everolimus Work?

Everolimus is a drug known as an mTOR inhibitor; rapamycin, the first mTOR inhibitor, was obtained from a bacterium in the 1970s and used as an antifungal drug. Later, when these drugs were found to suppress the immune system, they began to be used to prevent rejection of transplanted organs, and they are still used for this purpose. In the 1990s, it was discovered that mTOR inhibitors could be used in cancer treatment, and numerous studies were launched for this purpose. Cancer research first bore fruit in 2009, when Everolimus, an mTOR inhibitor, received approval from the United States Food and Drug Administration (FDA) for treating advanced kidney cancer. It later also received FDA approval for treating pancreatic neuroendocrine tumors and a type of breast cancer. So how do mTOR inhibitors affect cancer cells?

mTOR is an enzyme called a protein kinase, and it plays a key role in cell growth, proliferation, movement and protein synthesis. The finding that mTOR is overactive in many cancer types, including breast, prostate, lung, melanoma, bladder, brain and kidney cancers, prompted the idea that drugs suppressing this enzyme could be used in cancer treatment.