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Cancer Genetic Testing as Therapy and Decision Tool

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“New cancer drugs that target genetic mutations regardless of where the tumor is growing should expand the practice of genetic testing patients for such glitches…”

Almost like magic immunotherapy regimens can change the course of a cancer patient’s life. Even if the patient is running out of conventional treatment options. The challenge is knowing which cancer patients will benefit from which immunotherapy.

One of the most interesting discoveries about genetic testing, to me anyway, is the fact that cancer in your bladder (as an example) may not be traditional bladder cancer. The tumor’s genetic make-up may be that of a completely different organ.

That’s the good news. The bad news about immunotherapy regimes are:

  • The possible side effects of immunotherapy drugs.
  • Few patients seem to benefit from immunotherapy drugs
  • High cost of immunotherapy drugs

Possible Immunotherapy Adverse Events:

Oncology has spent years learning about and treating peripjeral neuropathy, nausea, alopecia, mucositis and more. These are some of the typical side effects associated with conventional chemotherapy. Oncology has relatively little experience identifying and treating the side effects that can come with immonotherapy regimens.

Immunotherapy Regimens are Oversold?

“When immunotherapy works, the result is terrific, even life-changing. Today, though, only a tiny minority of patients expected to die from cancer will benefit from immunotherapy. As is often the case, hype sadly exceeds evidence, creating misunderstandings between patients and their doctors…”

Cost of Immunotherapy Regimens:

He also noted it’s one of the reasons for rising healthcare costs, particularly in cancer treatment.While immunotherapy is nothing short of a miracle for some cancer patients, it doesn’t work for everyone.”

I am a long-term cancer survivor and cancer coach. I see immunotherapy regimens as one therapy tool among many. Genetic testing is a diagnostic tool that can give you information about the probablility of your cancer responding to a therapy. More than ever however, the cancer patient must do his or her research.

Do you have cancer? Are you considering immunotherapy? Have you undergone genetic testing? To learn more about your therapy options scroll down the page, post a question or comment and I will reply to you ASAP.

Thank you,

David Emerson

  • Cancer Survivor
  • Cancer Coach
  • Director PeopleBeatingCancer

Recommended Reading:


Immunotherapy

Immunotherapy is the “treatment of disease by inducing, enhancing, or suppressing an immune response”.[1] Immunotherapies designed to elicit or amplify an immune response are classified as activation immunotherapies, while immunotherapies that reduce or suppress are classified as suppression immunotherapies

‘Tumor agnostic’ cancer drugs seen boosting wider genetic tests

“New cancer drugs that target genetic mutations regardless of where the tumor is growing should expand the practice of testing patients for such glitches, oncology experts say.

Such “tumor-agnostic” drugs from companies including Merck & Co and Loxo Oncology may help overcome misgivings by health insurers, who have balked at covering large-scale tests looking for genetic mutations in tumors, and quell concerns of some top cancer doctors who question whether enough patients benefit from such tests.

Last month, Merck’s immunotherapy Keytruda became the first cancer treatment ever to win U.S. approval based on whether the tumor carried a specific genetic glitch, irrespective of the tumor’s location.

More recently, Loxo showed that its drug larotrectinib helped shrink tumors in 76 percent of patients with a wide variety of advanced cancers who carried a specific genetic defect.

The surprising results suggested a benefit of testing many patients for the same defects.

“Insurance companies had an easy out” before the Merck approval and Loxo data, said Dr. David Hyman of Memorial Sloan Kettering Cancer Center in New York. Hyman presented the Loxo results at the American Society of Clinical Oncology annual meeting last weekend.

“They have asked, ‘Show me the evidence this helps patients.’ It didn’t exist,” he said. “Now we have these data.”

A second company, Ignyta Inc, has developed a drug that targets the same genetic glitch as Loxo’s larotrectinib, and both treatments are under expedited review by U.S. regulators.

At the U.S. Food and Drug Administration, cancer chief Dr. Richard Pazdur said he is “very supportive” of the tumor-agnostic approach and believes more such approvals are likely…

Such evidence may begin to sway insurers, but it’s not clear how quickly. Aetna Inc said it is studying the Keytruda approval and will base its decision about testing based on the medical evidence and whether the treatments improve quality, reduce waste and provide members with access to affordable care.

Dr. Jeffrey Hankoff of Cigna Inc said the company “generally does not cover multi-gene panels” unless they are recommended by the National Comprehensive Cancer Network, a nonprofit group that sets cancer treatment guidelines.

“Ultimately, it’s a matter of having actionable information from genetic testing that is based on evidence, not on conjecture,” Hankoff said.

ENTHUSIASM WANING

In 2001, Novartis drug Gleevec transformed the treatment of chronic myelogenous leukemia (CML) from a fatal blood cancer to a treatable condition for most patients. The drug takes aim at a single genetic defect, raising hopes for a new age of targeted drugs that work better and more safely than traditional chemotherapy. Since then, gene sequencing has become exponentially faster and cheaper. Five years ago, companies such as Foundation Medicine introduced genetic profiling tests that look for a range of cancer-causing genes to match patients to a handful of targeted drugs for lung, skin and breast cancer or to clinical trials testing new agents.

Many doctors have embraced the practice, hoping to find a treatment for patients with advanced cancers who were out of options. But insurers have been slow to pay for the tests, which cost $1,000 to $5,000 and can result in the off-label use of targeted drugs with no evidence that they work.

In late 2015, a randomized trial showed such testing yielded no survival advantage compared with conventional therapy. The finding triggered a fierce debate in medical journals, with some experts questioning whether hype has gotten ahead of the science.

“There are patients that benefit, but it’s very much a minority of the patients,” said Dr. Scott Kopetz, a colorectal cancer specialist at the University of Texas MD Anderson Cancer Center.

Hyman argues that the Keytruda approval based on a single genetic defect “changed the field overnight” and will gain momentum with the likely approval of larotrectinib, which targets a defect called TRK fusions.

Experts estimate up to 1 percent of all cancer patients have TRK fusions.

Dr. John Heymach, an oncologist from MD Anderson Cancer Center in Texas who was not involved in the Loxo study, said it underlines “the importance of expanding what we’re looking for.”

Genetic mutations predict patient response to immunotherapy

“Because clinical tests for the particular indicator defects identified here are widely available, these results could establish a new standard of care to test for them in tumors, the authors say, helping to more efficiently identify those patients who might benefit from immunotherapy. In an 86-participant clinical trial across 12 different types of cancer, Dung Le et al. found the immunotherapy pembrolizumab (an anti-PD-1 antibody) was actually effective against multiple forms of cancer.

The drug controlled disease for 66 patients, and tumors completely disappeared in 18 people. The responding tumors all had defects in a genome maintenance pathway called mismatch repair (MMR). PD-1 blockade therapies can unleash the immune system against aberrant proteins on the surface of malignant cells called neoantigens, which accumulate because some cancers have inherently unstable genomes.

The researchers characterized neoantigens in biopsy sample responses from three responding patients to confirm that MMR-deficient cancers contained immune cells that can be let loose against tumors using PD-1 blockade.

The scientists determined that immunotherapy might be useful for as many as 60,000 MMR-mutant cancer cases every year in the United States, based on analysis of genome sequencing data from 12,019 cancers representing 32 distinct tumor types. Though the trial is still ongoing, 11 patients were able to stop taking the therapy since beginning; they have remained disease-free with no evidence of recurrence for an average of 8.3 months.

 

 

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