How Stem Cell Transplants Work to Treat Testicular Cancer
While the survival rates for testicular cancer are high—99 percent in localized, first-time cases—there are still types of testicular cancer that require more aggressive treatment. In the roughly 20 to 30 percent of patients for whom the standard chemo dose isn't successful, or in cases where the cancer is unresponsive, the chemo doses can be cranked up to help take on the disease.
According to the Dana-Farber Cancer Institute, high-dose chemo usually involves a patient receiving three cycles of three different chemotherapy medications over a course of three weeks (for nine weeks total). However, the regime can be individualized, especially depending on the status of the patient's lungs.
Przemyslaw Twardowski, M.D., director of clinical research in the Department of Urology and Urologic Oncology at Saint John's Cancer Institute in Santa Monica, California, noted that when you use high doses of chemo, not only are the cancer cells wiped out, but so are plenty of other healthy cells, like those of bone marrow.
And while the high-dose chemo may be effective in killing off the cancer, without bone marrow cells to generate normal blood cell production, the patient cannot survive.
Stem cell transplants to the rescue
Higher doses of chemo inevitably come with higher-level risks, which is exactly where stem cell transplants come in. While stem cells aren't a treatment for testicular cancer on their own, the transplants can help the patient recover from the impact of high-dose chemotherapy.
Stem cell transplants allow vital bone marrow cells to regenerate bone marrow for blood cell production after the high-dose chemo is administered. It works like this: Before getting the chemo treatment, blood-cell-generating stem cells are collected from the patient's bloodstream. Then, after the chemo treatments are completed, those cells are reinfused into the patient through an IV. Over time, those cells work to regenerate bone marrow.
Who qualifies for a stem cell transplant?
Because testicular cancer tends to be a disease that affects young males, the patient population is generally healthier than people with other types of cancers, which means many patients have the ability to withstand the high-dose chemo treatment.
However, even in a young, generally healthy population, Twardowski said, there are still pretty strict criteria to determine who's eligible for a stem cell transplant. You have to be someone who hasn't seen successful outcomes with standard chemotherapy treatment for testicular cancer. Moreover, because the high doses of chemo will potentially strain all of your organ systems—including the kidney, heart and lungs—those systems have to be in good shape to qualify.
If you fit all the necessary criteria, the use of a stem cell transplant may sound like a no-brainer. But the concept of utilizing it with high-dose chemo for standard-dose-resistant testicular cancer is still being studied, and the combination is not without risk, as the complications of using high-dose chemo can be severe, affect various organs and even be life-threatening.
However, Twardowski said that the preliminary data is promising. "The ongoing study will be much more definitive," he said. "It's not a slam dunk, but it may add an additional 20 percent cure beyond standard treatment."