Do you lie when a patient asks you a straight question? Or do you fudge the truth with euphemisms?
After all, how do you tell someone that he is dying?
What to tell, how much to tell and when to tell - every doctor struggles with these issues when dealing with a patient who has been diagnosed with a life-threatening illness.
Many people still think of cancer as a dreaded, fatal disease and oncologists are often the ones who have to break the news.
The task is really quite straightforward in the large majority of cases, especially if the patient is an adult and the prognosis is likely to be good.
The main message then is to ameliorate the fears and concerns of the patient and to discuss how to fight and beat the cancer.
But what if the patient is a child or an elderly person? What if the prognosis is guarded? Should we still tell the unvarnished truth?
As a general rule, I try to be as honest as possible when dealing with patients, especially adults, because I believe a person has a right to know everything about his own health But this is not always possible.
"Auntie" is a woman in her 80s. When she saw me three years ago, the referring doctor made the diagnosis of stage 4 breast cancer.
The cancer, which originated in her left breast, had already spread to the lymph nodes, bones and liver.
"Please don't tell her she has cancer," pleaded her family members, who had squeezed into my consultation room. They loved her dearly and felt that the diagnosis would break her spirit and prevent her from agreeing to treatment.
The patient had seen a surgeon some months earlier and he told her: "Ask all your children to come."
He said so because she needed immediate surgery to remove the breast cancer.
She was so frightened by the word "cancer" that she not only failed to comply, she never told anyone about the incident until her family members discovered the large tumour bulging beneath her blouse.
By that time, the cancer had already metastasised or spread and surgery was no longer an option.
After talking to her, I agreed with the family that it would serve little purpose to use the word "cancer".
Instead, I told her that there was "something dirty" growing inside her breast and that this could be "washed away" with medicine.
She accepted my explanation and agreed to have treatment.
Obviously, the medicine I was referring to was chemotherapy.
Over the past three years, "Auntie" has been in and out of my clinic almost weekly. The waiting room is often full of cancer patients - some with hair but many without.
Whether she suspects or knows that she has cancer, I really cannot be sure. But, I am inclined to believe that she knows and doesn't really want to confront the issue.
After all, the "dirty thing" in her left breast was getting better and she was tolerating the medicine that was helping to wash the "dirt" away.
Most people associate chemotherapy with hair loss, nausea, vomiting and weakness.
In reality, there are many chemotherapy programmes used in treating breast cancer that do not cause any hair loss.
Nausea and vomiting can be minimised or prevented by generous use of powerful anti-vomiting drugs such as ondansetron and aprepitant.
The weakness can be minimised by booster drugs to prevent anaemia and dropping of the patient's blood count.
As for "Auntie", all had been well until the last six months when the cancer started to show signs of resisting treatment.
I increased the doses of the chemotherapy in order to keep the disease under control.
Later, new drugs had to be substituted and her hair began to fall.
In the earlier years, her visits were often peppered with friendly banter about family, her daily activities and her faith in God. She treated me as though I was part of her family.
Of late, she knows that things are not going as well. The disease has spread from the left breast to the right side.
She attributes it to her fondness for crabs, which in the eyes of many Chinese contain poisonous substances that can cause skin problems.
Each time I see her, I struggle with myself as to whether I should tell her that this is not just a "skin problem" or "something dirty" but, in fact, cancer.
I have consulted her family members and they are vehemently opposed to my suggestion that she be told.
So I keep up the charade.
I comfort myself by rationalising that it is for the best because she already knows she has a serious illness, but is unprepared to face the truth.
Or perhaps I am the one unprepared - to burst her bubble and give her the grim version of reality.
This article first appeared in "Mind Your Body", a Straits Times Supplement.