It was the day before Labour Day and the clinic was exceptionally crowded.
The public holiday meant that we had a shorter work week.
As patients on chemotherapy were scheduled for their consultations and treatment according to planned treatment protocols, we had to squeeze more patients than usual into each working day that week.
The waiting time was very long that day. I trudged along at my usual pace, refusing to be distracted or rushed by the crowd.
Most of my patients are familiar with the waiting time.
Time and again, I have explained how important it is for me to spend as much or as little time as each patient requires, depending on the complexities of the case and the needs of the patient.
Some patients spend barely five minutes in the consultation room - they have come for their routine follow-up and all is well.
Other patients end up requiring up to an hour, as there are problems that have to be addressed.
On that day, I thought things were running pretty smoothly. Most of the visits were straightforward and there were no major issues or crises.
Suddenly, the zen was broken by loud shouting in the waiting room. A patient in her 60s, whom I shall call Mrs Dewi (not her real name), was screaming at the staff manning the reception counter.
In my 18 years of private practice, I have never heard such shouting in my clinic. My distraught staff came running to the consultation room, saying that Mrs Dewi was unhappy about the long wait.
I first met her nine weeks earlier. She had abdominal discomfort and was diagnosed with stage 4 stomach cancer.
The positron emission tomography-computed tomography (PET-CT) scan showed a thickened stomach wall, and that the cancer cells had spread to the abdominal lymph nodes.
More devastatingly, almost half of her liver had been replaced by cancer metastases.
Clearly, the disease could not be cured. But it could be treated.
Initially, Mrs Dewi was reluctant to undergo treatment. But after a lengthy deliberation, she decided to proceed.
The first cycle of chemotherapy went well. However, she was unhappy after the second cycle - she felt that the nurse had ignored her concerns that her arms felt cold during the infusion of intravenous fluids.
She also complained that her left leg was aching and blamed it on the attending nurse.
When I examined her leg, I noted that the left leg was slightly more turgid than the right.
I explained to her that she could have developed deep vein thrombosis (DVT).
This condition is often described as "economy class syndrome" as it can occur in airline passengers who have not moved their legs for long periods on flights. The sluggish flow of the blood leads to the formation of blood clots in the legs.
In cancer patients, this can happen because cancer can cause the blood to become stickier, resulting in blood clots in the legs.
These clots can migrate to the heart, leading to a pulmonary embolism, when the clots cause blockages in the blood vessels leading from the heart to the lungs.
Sufferers of this syndrome often experience shortness of breath, chest discomfort and may even die suddenly, just as in a massive heart attack.
We did a Doppler ultrasound test on Mrs Dewi's leg - and, indeed, it was DVT. I started her on a blood thinning injection (to make her blood less sticky) and by the next day, she felt better. I made it clear to her that the DVT had nothing to do with the nurse or the infusion.
I also explained the need to place a filter in the abdominal vein, called the inferior vena cava, to prevent any clots from migrating to the heart.
She agreed to have the procedure, but wanted to have it done in her home country of Indonesia.
When she turned up for her third cycle of chemotherapy, I was shocked that she did not have the filter in place and had missed her blood thinning injections.
I spent a long time explaining the dangers of DVT. In the end, she had the filter fitted here.
On the day of her outburst, she was scheduled for a review of her post-treatment PET-CT scans.
When I heard the shouting at the reception counter, I called Mrs Dewi into the consultation room immediately. Before she stepped in, I quickly reviewed her medical records and PET-CT results.
She entered the room with a broad smile and a friendly greeting - without a trace of her anger earlier.
I showed her the PET-CT scans and said that she had responded very well to the chemotherapy.
Almost all the cancerous lesions had disappeared.
I was elated at the results but, at the same time, dismayed at her behaviour towards the nurses. I explained that it was unacceptable.
I went on to prepare a medical report detailing the treatment I had given her and explained that I could no longer continue to look after her.
To be honest, as I reflected on my decision to discharge her from my care, I questioned myself whether I had made the right decision.
Till today, I am not sure.
Part of me tells me that I should have just carried on my duties as a doctor.
The other part says that once that special doctor-patient relationship is broken, it is better for both parties to part company.
My wife, with her usual wisdom, reminded me that I should also watch how I behave.
In his Labour Day message, labour chief Lim Swee Say, who is the secretary-general of National Trades Union Congress, said that we must strive to be a nation of better customers and better people.
Indeed, behaving well towards one another should be reciprocal, but should a doctor's care be unconditional?
I have long told myself that part of medical care is to be able to withstand any emotional or physical weight that the patients place on me.
Does that include tolerating poor behaviour in my clinic towards the nurses, which also causes distress to other patients?
This is a question which I answered in haste on the day before Labour Day, but one which I continue to ponder today.
Dr Ang, the medical director of Parkway Cancer Centre, has been treating cancer patients for 23 years. In 1996, he was awarded Singapore's National Science Award for his outstanding contributions to medical research.
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