Doc Talk

Ain't no mountain high enough

As a ranger to my cancer patients, I show them the easiest path up the mountain of treatment

It was frost and snow for as far as the eye could see.

I made an impulsive decision 11/2 years ago to climb the highest mountain in Korea - Hallasan on Jeju Island - in winter.

Just as I was about to set off at the foothills, doubts started to grow in me as I contemplated the daunting task ahead.

Thankfully, the rangers at Hallasan National Park were there to advise and encourage me.

With the knowledge and experience they had of the ground, they kindly pointed me to the easiest climbing trail - one clearly marked and with ropes in place to help mountaineers with the ascent at the steepest and most hazardous parts.

I made it to the top, thanks to the rangers.

At my clinic, my role is often flipped. I become the ranger and my cancer patients are the climbers.

But fighting cancer is a far more daunting task than climbing a snow-capped mountain.

As their ranger, I see it as my duty and mission to steer my patients away from danger and to guide them to the easiest path up the rugged mountain of cancer treatment.

Madam Deepa (not her real name) is a middle-aged woman with advanced breast cancer that has spread to her liver and bones.

Together, we sought to conquer her cancer which loomed as the tallest mountain to her - psychologically.

I, the ranger, and she, the climber.

It is a climb that has lasted 14 years to date. The climb started relatively easy as her breast cancer was sensitive to hormonal treatment.

For advanced breast cancer where hormonal therapy is deemed effective, it is usually preferred over chemotherapy treatment as the side effects of hormonal therapy are usually minimal.

When the cancer progressively developed resistance to various forms of hormonal therapy, the climb became tougher.

Extended periods of chemotherapy became necessary to keep her cancer in check.

It wasn't an easy time.

There were moments when extreme fatigue set in, when the determination to carry on was shaken.

Months ago, one such moment occurred.

After being on a fairly extended course of one of the latest chemotherapy regimens, cancer resistance to the treatment was setting in.

To complicate the problem, she was starting to feel significant side effects from the chemotherapy.

These side effects tend to be cumulative over time.

Her energy level was down. She was losing sensation in her fingers and toes.

We were faced with two stark options - start yet another chemotherapy regimen and risk compounding the side effects she was feeling, or risk losing control of her cancer.

Fortunately, an easier path was found. A new therapy, known as palbociclib, could shut down the resistance mechanism that blocks the effectiveness of hormonal therapy.

Cancer cells make use of the female hormones in the patient's body to generate a growth signal allowing them to grow and multiply.

This signal can be shut down by hormonal therapy, which has been in clinical use for decades.

But after a while, the cancer cells learn to switch on an alternative pathway to generate the growth signal, so that they can return to their previous happy state of uncontrolled growth and multiplication.

Palbociclib cuts off this backup signal pathway.

If it is used early, prior to the onset of resistance to hormonal treatment, patients can expect to live, on average, an additional 10 months without any worsening of the cancer.

If it is used late, after resistance has set in, the extension of life without the cancer worsening is approximately five months.

This new targeted therapy was approved in the United States by the Food and Drug Administration last February, on the back of impressive benefits that it brought to patients suffering from advanced breast cancer.

Permission was sought with the Health Sciences Authority (HSA) for Madam Deepa to access this new therapy under a special compassionate-use programme.

As a result, she is still alive and well today.

Her breast cancer was kept under control by the new treatment for over half a year.

Not only did it prolong her life, it also bought an important respite from the side effects of past chemotherapy, allowing that to blow over and restore her quality of life.

By the time the cancer developed resistance to palbociclib and started to grow again, she was well enough to resume chemotherapy and the cancer was brought into remission again.

Palbociclib was approved by the HSA last month. I now have the option to use this treatment earlier, thus effectively delaying the onset of resistance to hormonal therapy and the need to start chemotherapy by almost two years.

It costs about $7,000 to $8,000 a month and comes in the form of a tablet taken every day for 21 days continuously, followed by a week of rest.

It can potentially benefit two out of every three women with advanced breast cancer.

I have always counselled my patients not to fear the use of chemotherapy, should the need arise.

However, if there is a way to delay the need for chemotherapy, if there is an easier way up the mountain, I, as the ranger, have a duty to guide them on this easier path.

• Dr Wong is a medical director and consultant medical oncologist at The Cancer Centre, Singapore Medical Group. He has been looking after cancer patients for the past 20 years. He is also an adjunct clinician scientist in the Institute of Bioengineering and Nanotechnology at the Agency for Science, Technology and Research.

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A version of this article appeared in the print edition of The Straits Times on August 09, 2016, with the headline Ain't no mountain high enough. Subscribe