TNBC has long been considered to be more amenable to immune system-based treatments than other types of breast cancer because it is more immunogenic; that is, relatively high levels of immune cells accumulate within or adjacent to TNBC tumors. These immune cells could be triggered to attack tumors if properly activated. TNBC tumors are also likely to have a higher mutational burden (number of genetic mutations). This is one of the predictors of sensitivity to a type of treatment called immune checkpoint blockade. Drugs known as checkpoint inhibitors block the proteins PD-1 or PD-L1. In cancer, PD-L1 proteins on tumor cells bind to PD-1 proteins on immune T cells and inhibit their tumor-killing activity. Immune checkpoint drugs disable this interaction and enable activation of T cells. These drugs are actively being explored in TNBC in clinical trials.
“President Jimmy Carter’s battle with metastatic melanoma to the brain has placed increased attention on management of this disease. President Carter was treated with focused stereotactic radiation to the brain and anti-PD-1 therapy. Researchers at Moffitt Cancer Center recently reported the first series of patients treated with this combined modality approach. They found that radiation therapy combined with the immune-targeting drug nivolumab in melanoma patients with brain metastases is safe and improves their survival compared to historical data.
“Nivolumab is a therapeutic agent that targets a protein on immune cells called PD-1. Binding of PD-1 to its ligand PD-L1, which is found on tumor cells, causes immune cells to decrease their activity and allows cancer cells to escape immune detection and cell death. Nivolumab blocks the PD-1/PD-L1 interaction and restimulates the body’s own immune system to target tumor cells. Nivolumab has been approved by the Food and Drug Administration to treat advanced non-small cell lung cancer, renal cell carcinoma, and melanoma; however, the impact of nivolumab on brain metastases is unclear.”
“The surface has only been scratched in the investigation of radiation and immunotherapy in combination for the treatment of patients with prostate cancer, says Steven Finkelstein, MD, of 21st Century Oncology.
“ ‘There is so much undiscovered territory with respect to this research. The fact there that are only a few clinical trails now of any significance in this area means that we need to do more work,’ says Finkelstein, a Scottsdale board certified radiation oncologist, adjunct associate professor at Translational Genomic Research Institute, and executive director of the Arizona Cancer Research Alliance. ‘I’ve spent a career working on this topic, and only now, after 20 years, are we starting to make progress.’
“While progress has been slow, the outlook is bright for the use of immunotherapy and radiation together in prostate cancer, says Finkelstein. He is currently working on a multicenter trial, which is investigating the effects of radiation therapy to augment anti-tumor responses from immunotherapy with sipuleucel-T (Provenge).”
“Emerging data showing improved survival with targeted and immunotherapeutic approaches are rapidly altering the standard of care for patients with melanoma. For BRAF-positive patients with metastatic or unresectable melanoma, the standard of care includes a BRAF inhibitor in combination with a MEK inhibitor. For patients with or without BRAF mutations, there are immunotherapeutic options available in frontline and in resistant disease settings.
“Questions remain, however, in terms of how to optimally sequence and/or combine both targeted agents and immunotherapies. And, for BRAF-mutant disease, when is it appropriate to switch from a targeted approach to an immunotherapeutic one?”
“Although nivolumab (Opdivo) and ipilimumab (Yervoy) together demonstrate superior survival in previously untreated patients with advanced melanoma, the combination comes with additional toxicity and an increased price tag, says Jason Luke, MD, assistant professor of Medicine at the University of Chicago Medicine.
“ ‘There have been several studies designed around trying to predict which patients are most likely to benefit from anti–PD-1 or immunotherapy combinations. I really think that is going to be an essential part of the future approach to treatment, says Luke. ‘Not all patients respond to these treatments. There are additional toxicities with the combinations, and there are also cost issues because of how catastrophically expensive these drugs are. We really need to know which patients are most likely to respond and which aren’t.’ “
“New immunotherapy drugs to treat a wide swathe of cancers, are the game changers of 2015, according to dozens of oncologists who responded to MedPage Today.
“When we asked oncologists about ‘game-changers’ in 2015, 37 of the 50 cited immunotherapy drugs.
“One reason for the clear consensus: It was a year in which checkpoint inhibitors spread into new tumor types.
” ‘Initially found to be useful in such immune-sensitive malignancies as melanoma, renal cell carcinoma, and Hodgkins disease,’ said Robert J. Mayer, MD, of the Dana-Farber Cancer Institute in Boston. ‘It has now shown major promise in more difficult cancers such as squamous cell and adenocarcinomas of the lung and even a subset (microsatellite unstable) of colon cancer, gastric cancer, and esophageal cancer.’ “
Large numbers of immune cells (T cells in particular) are frequently found within or adjacent to melanoma tumors, indicating that the tumors attract the attention—if not the action—of the immune system. True to its reputation as one of the most ‘immunogenic‘ cancers, melanoma now has more U.S. Food and Drug Administration (FDA)-approved immunotherapy (immune system-targeting) drugs than any other cancer type. As a consequence, metastatic melanoma is no longer the universally fatal disease it was even just 3 or 4 years ago. Continue reading…
“A Yale-led international study in patients with advanced non-small cell lung (NSCLC) cancer resistant to chemotherapy has found a promising weapon in an immune therapy drug commonly used to treat other cancers. The findings were published Dec. 19 in The Lancet and presented at the 2015 annual conference of the European Society for Medical Oncology in Singapore.
“The study, called KEYNOTE 010, compared pembrolizumab with the chemotherapydrug docetaxel in 1,034 patients with NSCLC whose tumors expressed the PD-L1 biomarker. PD-L1 is a protein expressed by many tumor types that can render the cancer invulnerable to immune attack. The study endpoints were overall survival (OS), progression-free survival (PFS), and safety.”
“Results from a long-term clinical trial conducted by cancer researchers at Houston Methodist Hospital show that combining radiation treatment with “suicide gene therapy,” a technique in which prostate cancer cells are genetically modified so they signal a patient’s immune system to attack them, provides a safe and effective one-two punch against the disease.
“The researchers compared two arms of patients and report high five-year overall survival rates of 97 percent and 94 percent, respectively. That’s a five to 20 percent improvement for survival over historical studies. These findings are in the Dec. 12 online issue of the Journal of Radiation Oncology(JRO).”