The following article by Professor Soo Khee Chee is from Mind Your Body of the Straits Times dated 3 Feb 2011, Thu.
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Odds of surviving cancer
By Professor Soo Khee Chee
One of the most common problems for doctors is to reassure patients diagnosed with cancer and their relatives that cancer is not a death sentence.
And one of the pleasures of working as a surgical oncologist is to see patients who had a seemingly incurable disease turning up at my outpatient clinic 10 to 15 years after treatment.
At the point of diagnosis, patients are often overwhelmed with thoughts of dying and pain.
The danger with such thoughts is that they cause pessimism and desperation, which sometimes lead to irrational decision making.
In truth, with so many advances in surgical techniques, radiation facilities, imaging technology and cancer drugs, the chances for survival have improved dramatically.
With World Cancer Day being marked tomorrow, we look at the many factors that determine the probability of survival. Perhaps one of the most significant is the stage of the cancer when the patient is diagnosed.
We generally divide the development of cancer into stages 1 to 4. Those with stage 1 cancer almost invariably survive while the chances of survival for those with stage 4 cancer are significantly less, though not hopeless.
Take, for example, Ms N, who was referred to me seven years ago when she was 20 years old. To my horror and sadness, she had stage 4 cancer in her head and neck.
Her treatment required mutilating surgery involving the removal of her eye and several lymph nodes from her neck, followed by radiation and chemotherapy.
Three years ago, she was diagnosed with another cancer in her pancreas and had to undergo surgery again.
This brave soul just returned for a review two weeks ago. She graduated from university some years ago and was voted the best worker in her department for her outstanding capabilities and cheerful disposition.
Each time I see her, I am inspired by her fighting spirit.
A second factor in determining one's probability of survival is the location of the tumour, though again, there is sometimes great variance.
For example, in thyroid cancer, the most common variety (papillary cancer) has a 20-year survival rate of 90 per cent, while for the most aggressive variety (anaplastic cancer), 90 per cent of patients are dead within six months. I tell my medical students that if one were to have a choice, I would wish a papillary cancer for myself and for my enemy, an anaplastic cancer.
Similarly, most common skin tumours do very well but others have a relentless growth rate leading to rapid demise.
One such skin tumour is a cancer arising from the blood vessels on the skin - angiosarcoma. In our experience, this tumour is nearly always fatal as it is resistant to chemotherapy and recurs after being excised or given radiation.
Fortunately for Mr M, who had this disease on six sites on his forehead, at the back of his neck and either side of his arms, an experimental therapy being used in a clinical trial at National Cancer Centre Singapore (NCCS) worked. This involved administering a light-sensitive drug and shining a laser light over the tumours some hours later.
Mr M has been disease-free for five years now.
A third factor is individual biological variation. For some inexplicable reasons, some people have cancer that develop aggressively despite being treated at an early stage, while others with late-stage cancer survive much longer than expected.
Ms J, a 26-year-old woman, noticed an ulcer on her tongue during the late stage of her pregnancy. It was diagnosed as a stage 1 cancer and she was treated in another country.
In our experience, those with such cancer have a five-year survival rate of 85 per cent. Unfortunately, the cancer recurred within four months.
We further resected her tongue and neck and gave her chemo-radiotherapy. But our treatment did not succeed and she died within six months.
On the other hand, Mr S, whom I operated on 20 years ago for stage 4 stomach cancer, has remained well when the five-year life expectancy was less than 10 per cent.
Much cancer research is directed to understanding the exact biological factors which sometimes override the stage of the disease in determining survival.
We are in the genomic era and efforts are being made to further characterise cancer based on their molecules. This molecular profile will determine the need for additional treatment and targeted chemotherapy. Personalised cancer treatment based on such research is here, though there is still a lot we do not know.
The fourth factor is the medical team treating the patient with cancer. In a recent publication, it was noted that the choice of the treating physician was as important as the stage of the disease in determining the survival of the cancer patient.
Patients will get the best advice from a multi-disciplinary team that includes surgical, medical and radiation oncologists, and radiologists and pathologists to give input on X-rays and tissue diagnoses. These doctors are often sub-specialists managing a large number of cancer patients in their specific fields. As a result, they are very experienced.
Mrs T, who consulted me 10 years ago, had three operations for recurrent colon cancer. In her last operation, a month prior to seeing me, the surgeon made a cut but then closed it without removing the tumour because it looked inoperable.
We undertook this 10-hour operation and today, she remains disease-free.
The bottom line: Surviving cancer is dependent on many factors and includes making complex decisions.
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Professor Soo Khee Chee is the director of National Cancer Centre Singapore. He is also the vice-dean for clinical and faculty affairs in Duke-NUS Graduate Medical School and the deputy chief executive officer for research and education in Singapore Health Services
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