Tag: Radiation

Premier MRI-Guided Radiotherapy Technology Enables Real-Time Tumor Tracking

Radiotherapy is a core element of prostate cancer treatment, yielding cures in men with localized disease. The goal of prostate cancer radiotherapy is to deliver high doses of radiation to the prostate gland while avoiding the surrounding bladder and rectum, thus preventing unwanted urinary and gastrointestinal side effects and preserving patient quality of life.

Radiotherapy guided by magnetic resonance imaging (MRI) allows clinicians to visualize a tumor as well as its neighboring organs in order to most accurately deliver treatment to the target region.

Weill Cornell Medicine and NewYork-Presbyterian Hospital (WCM/NYP) are proud to be the first – and only – medical institution in the northeast to offer patients the most premier MRI-guided radiotherapy technology available: the MRIdian Linear Accelerator, by ViewRay. The MRIdian Linac’s unique ability to track a patient’s tumor in real time during treatment makes it by far the most advanced modality of delivering radiation.

Real-time visualization is significant due to the constant flux of internal human anatomy, including changes in respiration, digestion and bladder fill that can influence the position of the prostate within the body. Even a minor shift of the tumor target during treatment can have major implications related to potential side effects of radiation. If the bladder or rectum displace the prostate during treatment, the MRIdian Linac machine will cease delivery of radiation and not resume until the prostate moves back in bounds of the target region. Whereas other modalities track small fiducial markers implanted in the prostate, this machine allows clinicians to see and track the tumor itself.

In addition, WCM/NYP is the only center in the area to offer combined use of MRI-guided radiotherapy with the rectal SpaceOAR, a hydrogel barrier that is temporarily placed between the prostate and rectum to shield the rectum from radiation and further reduce potential side effects.

Watch the video below to learn more about this state-of-the-art technology from WCM/NYP radiation oncologist Dr. Himanshu Nagar.

 

Using Radioactive Particles to Kill Cancer Cells

Radioisotopes, or radionuclides, are particles that emit energy. Some of these particles (alpha and beta particles) emit damaging radiation that can be attached to carrier molecules to directly target cancer cells within the bloodstream. We at Weill Cornell Medicine and NewYork-Presbyterian are proud to offer clinical trials utilizing both types of radioisotopes.

AlphaBeta

Find out more about how our team uses radionuclide therapy to treat genitourinary cancers. 

 

First-Ever Clinical Trial Testing PSMA-Targeted Antibody and Radioactive Alpha Particles for Treatment of Advanced Prostate Cancer

Radiation is one of the most common treatments for prostate cancer. Using radiation, physicians are able to cure some men with cancer confined to the prostate, as well as improve symptoms for men with metastatic disease. There are many different types of radiation treatments.

One type of treatment includes injecting radioactive isotopes into the blood in order to directly reach the prostate cancer cells regardless of where they are located in the body, including the cells that have spread to the bone and other organs. For example, Radium-223 (Xofigo) is FDA-approved to treat prostate cancer that has metastasized to the bone and has been shown to improve both the quality and duration of the lives of men with advanced prostate cancer.

Screen Shot 2017-10-25 at 2.20.19 PM
Red marker = PSMA, Green = radiation, demonstrating that the drug targets the cancer cell directly.

Radioimmunotherapy or radioligand therapy involves the practice of attaching a radioactive isotope to a cancer-targeting antibody or small molecule that binds only to a specific cancer-related molecule on a tumor cell. This is similar to a “lock and key” scenario, where the antibody or molecule resembles the key that will only recognize a very specific lock (the cancer-related molecule).

Essentially all prostate cancers have a specific “lock” called prostate-specific membrane antigen (PSMA). This “lock” is a protein that sits on the surface of most prostate cancer cells but is absent from most other normal places in the body.

Physicians and scientists have engineered very specific “keys” in the form of monoclonal antibodies and molecules that will bind only to PSMA. When we attach radioactive particles to these keys, we are able to deliver what we call “molecularly targeted” radiotherapy.

For example, J591 is a monoclonal antibody (an engineered protein) that recognizes PSMA. Actinium-225 (225Ac) is a small radioactive particle that emits alpha-particles, a powerful form of radiation requiring fewer particles to cause damage to the cancer cells. When these are attached to one another, we call the compound 225Ac-J591 (a radioactive particle linked with a monoclonal antibody). It is designed so that J591 will recognize the PSMA on the prostate cancer cells and bring the radioactive particle 225Ac with it into prostate cancer cells wherever it goes in the body.

Our physicians and scientists are building on prior laboratory-based research presented at the 2017 Meeting for the Annual Association for Cancer Research (AACR) and are now studying the role this experimental therapy may have for men with advanced prostate cancer that has spread throughout the body. Thanks to generous support from the Prostate Cancer Foundation and the NIH SPORE award, Dr. Scott Tagawa, medical oncologist and Director of the Weill Cornell Medicine Genitourinary (GU) Oncology Program, and his team are conducting the first-ever clinical trial testing the PSMA-targeted antibody and radioactive alpha particles (225Ac-J591) for treatment of advanced prostate cancer. This promising new and unique approach has the potential to lead to another treatment option for those patients who are not experiencing the best clinical outcomes possible from standard of care therapies. Some men in Germany have received 225Ac linked to PSMA-617 with a handful of cases published with impressive responses. However, no formal studies have been performed and there are reports of bothersome dry mouth (xerostomia) and the potential for delayed kidney damage (seen in mice).

“We look forward to advancing science and also making this treatment available to men with advanced prostate cancer in the near future, says Dr. Scott Tagawa. “Our goal is to translate the existing knowledge base into true clinical gains for prostate cancer patients and it’s great that in October, 2017, we are able to treat our first patient.”