Perhaps, doctors struggle more than most with memories that mark sad moments in their careers. For me, one of the most indelible was of a wonderful young man with chronic myeloid leukemia (CML).

When I started my oncology career in the early 1970s, CML was almost always fatal. It would start with a chronic phase, which was treated with pretty simple medications. But those medications didn’t cure the disease.

The “almost always” scenario with CML was that several years on, it would morph into an acute phase, or “blast crisis,” that almost always ended in an untimely and frequently very premature death.

I came in contact with this young man just as he was diagnosed with CML. A couple of years later, he entered that acute phase. Rather than face the rigors of intensive chemotherapy, a regimen that was almost always futile, he took his own life. Moments like that live with us forever.

Decades later — 2003 to be exact — a prominent oncologist, who at the time was the director of the National Cancer Institute, made an audacious promise. Andrew von Eschenbach said that by 2015 we would end the suffering and death from cancer and convert it to a chronic disease, much like hypertension and diabetes.

That prediction generated a lot of comments — some positive, many not so positive. But as it turns out, progress against CML, the disease whose prognosis was so bad as to make a young man choose a premature death those few decades ago, is the case study that shows Dr. von Eschenbach’s vision was not as far-fetched as some have come to believe.

A report in the current issue of the Journal of Clinical Oncology from Swedish researchers reviewed the records of all patients 50 and over diagnosed in Sweden with CML between January 1973 and December 2013. They then compared their survival at different periods of time with that of the general population in Sweden.

The researchers report that beginning in 1990, life expectancy began to creep up among CML patients in every age group, even in those diagnosed at age 85. The key result of their report: life expectancy “in 2013 approached that of the general population.”

In practical terms, the authors explain that a 55-year-old male diagnosed with CML in 1980 would have three and a half years of life remaining, while if that same 55-year-old gentleman was diagnosed in 2010 he would have 27.3 years of life remaining. Even 85-year-old people saw their lives extended: an 85-year-old male diagnosed in 1980 would live about 9 to 10 months after diagnosis. While if diagnosed in 2010, he would live more than four years.

One would assume that almost all of this improvement was due to a targeted therapy called imatinib, introduced at the beginning of this century. Imatinib did lead to improved survival, but some of that improvement was actually seen beginning in 1990 — well before that drug became available. And now, with yet more targeted therapies available to treat CML, we are able to provide effective treatments to many of those who either don’t respond to imatinib or become resistant to it.

This is, in human terms, a very dramatic story.

Yes, there are side effects to these drugs and treatments, including an increase in cardiovascular disease and, perhaps, an increase in the number of other cancers.

But for me, the enduring message is that maybe the audacious, oft-ridiculed prediction that we could cure cancer by 2015 had more validity that we recognize. With CML and for other cancers, we are turning cancer into a chronic disease for some patients. CML has led the way in this development. And even if it is a relatively uncommon cancer, seeing the enormous progress we’ve made in just the past 15 years should give us the will to continue to strive for similar progress for many more.

This progress came too late for that patient I now remember from some forty years ago and for countless others. It is in honor of their memory that we should never give up on our goal; we should never abandon hope. Because for the thousands of people diagnosed with CML who’ve benefitted from the advances of the past decade, that doctor was right on target. They are the living proof.

J. Leonard Lichtenfeld is deputy chief medical officer, American Cancer Society. He blogs at Dr. Len’s Cancer Blog.

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