Newer Cancer Treatments and the Science Behind Them

Todays treatments, yesterday's advances and fun ways to learn.

Today’s treatments are resulting in many people with leukemia and lymphoma living longer than ever before.

Treatment advances are an important part of this progress, but so are other advances -- namely, scans and imaging studies that help doctors evaluate disease initially, monitor the response to therapy, and watch out for recurrence. Still, prognosis and survival times vary widely today. With some aggressive lymphoma types, survival may be measured in months, while with others, people routinely live a decade or more following diagnosis and treatment.

Advances in the way certain malignancies are managed do not necessarily provide benefits across the board in treating blood cancers. The Leukemia and Lymphoma Society, or LLS, lists the following milestones in association with its research efforts:

Therapeutic Advances – Courtesy of the LLS

1950s: First chemotherapy agents for lymphoma and leukemia patients, including children

1960s: First combination chemotherapy developed for childhood leukemia

1970s: First successful bone marrow transplants performed

1980s: Cancer-causing oncogenes and tumor suppressor genes discovered

1990s: Antibody-based therapies such as rituximab

2000s: Targeted therapies such as Gleevec

2010s: Genomic medicine and precision medicine; immunotherapy.

2020s: Personalized medicine cures and prevention.

How Does PET/CT Imaging Factor into Treatment?

PET/CT can help identify cancer involvement and detect in lymph nodes and other sites that have become involved with the disease.

So how does this impact treatment? Well, using these scans provides doctors with a detailed map of where in the body the cancer is and where it isn’t. Based on this map, for diseases like Hodgkin lymphoma, or HL, doctors can develop a good idea of which therapies to start with initially.

The staging system for HL is known as the Cotswold system, which is a modified form of the older Ann Arbor system.

Though modified, it is still anatomically based. The precise staging based on the anatomy of involved sites is considered important in HL because anatomical stage correlates strongly with prognosis and helps determine treatment.

With non-Hodgkin lymphoma, or NHL, it’s not that anatomical staging is unimportant, but rather that other factors – such as the microscopic appearance and cellular characteristics – tend to be better at predicting a prognosis and therefor influence the treatment decision more.

In HL, stages I and II have typically been treated with radiation therapy, while a combination of radiation and chemotherapy or chemotherapy alone may be offered to patients in stages III and IV.

How Do Newer Treatments Work?

The basic types of treatments for diseases like leukemia and lymphoma include chemotherapy to kill the cancer cells, radiation to kill the cancer cells and shrink tumor masses, and a variety of other therapies that try to selectively leverage the biology of cancer cells to exert a beneficial effect.

Some newer therapies work by helping the immune system to detect and kill cancer cells. There are different ways to accomplish this. One way is to aid the immune system’s ‘soldiers,’ the T lymphocytes, or T cells.

Cancer cells have antigens that mark them as harmful. Special cells in the immune system can capture these antigens from cancer cells present them to T cells, the ‘soldiers,’ inside lymph nodes. When a T-cell sees a cancer antigen under the right set of circumstances, it becomes activated – ready to seek and destroy.

Gaming and Cancer Therapy Education

Genentech, a company known for innovative therapies, has developed a number of video games in the interest of making science fun. They aim to bring the science of cancer and the immune system to the people, in a fun and engaging way.

For instance, in the following game, your are a dendritic cell – as special ‘scout’ in the immune system – and your goal is to find the T cell within the maze of a human lymph node:

Computer game - "Lymph Node Labyrinth"

Antigen presentation and T cell activation are key steps in what is known as the Cancer Immunity Cycle – see Cancer-Immunity Cycle - Review and Roundup for more. Antibodies are products of the immune system, and they, too, have a role in today’s cancer treatments.

A different game involves an Angry Birds-style slingshot in the form of a bio-engineered antibody -- the basis for many modern bio-pharmaceuticals -- and there is a shooting gallery full of potentially cancerous cells:

Computer game - "T Cells Attack"

T cells represent the immune system’s army. Some cancer cells, however, have evolved ways of hiding from the immune system. The goal of cancer immunotherapy is to activate the body’s own immune system in order to recognize and destroy cancer cells.

Sources:

The Leukemia & Lymphoma Society. https://www.lls.org/who-we-are/research-successes. Accessed November 2015.

Cheson BD, Fisher RI, Barrington SF et al. Recommendations for initial evaluation, staging and response assessment of Hodgkin and non-Hodgkin lymphoma: the lugano classification. J Clin Oncol. 2014;32(27)3059-3068.

Barrington SF, Mikhaeel NG, Kostakoglu L, et al. Role of imaging in the staging and response assessment of lymphoma: consensus of the international conference on malignant lymphomas imaging working group. J Clin Oncol. 2014;32(27):3048-358.

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