Building A Treasure Chest Of Medical Data

Professor Kanagaratnam Shanmugaratnam set up the Singapore Cancer Registry in 1967, a time when everything had to be done by hand; this meant meticulously transferring decades of data to now-obsolete punch cards.

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AsianScientist (Mar. 23, 2016) – Kanagaratnam Shanmugaratnam, emeritus consultant at the National University K Hospital (NUH) and emeritus professor of pathology at the National University of Singapore (NUS), holds court in his NUH office, surrounded by the tools of his trade—microscope, slides and years of carefully-collated reports.

Sprightly, razor-sharp and Internet-savvy at 94, Singapore’s “Father of Pathology” exudes an air of calm, methodical professionalism.

“I’ve been looked after very well by all the consultants here,” he says matter-of-factly, referring to the three stents in his heart.

Professor Shanmugaratnam has been working continuously in the field of histopathology—a medical specialty in which diseases are diagnosed by the microscopic examination of tissue samples—since 1948. He is best known for establishing the Singapore Cancer Registry (SCR), a treasure trove of data that has proved invaluable to clinicians, researchers and public health administrators seeking to monitor and control cancers afflicting the Singaporean population. He is also an internationally-renowned expert on nasopharyngeal carcinoma, a cancer of the upper respiratory tract, which disproportionately affects ethnic Chinese.


The war years

Professor Shanmugaratnam enrolled at Singapore’s King Edward VII College of Medicine in 1938. But the Second World War and the attendant Japanese occupation of Singapore, which lasted from 1942 to 1945, interrupted his studies. Left adrift, he and his fellow medical students had to find work of some sort to avoid being taken away for manual labour.

The Japanese Army Medical Corps had taken over and converted the College of Medicine building into bacteriology and serology laboratories. Professor Shanmugaratnam found work there as a laboratory technician, and later also at the Chuo Byoin (Central Hospital)—the pre-war KK Women’s and Children’s Hospital, which during the war was turned into a general hospital for local and Japanese civilians.

“It was a very tough time, of course—no medications, and difficulties with food and personal safety,” he says. “But as far as laboratory work was concerned, under limited circumstances, we did fairly well. It was during those years that I developed an interest in pathology. I was always interested in laboratory work on the science side, rather than the actual care of patients.”

Professor Shanmugaratnam’s classes at the College of Medicine resumed in June 1946. He graduated in 1947, and joined the Government Medical Service as an assistant pathologist the following year. He went on to complete a PhD in pathology at the University of London in 1957.


Cataloguing decades of data

In 1950, keen on observing local disease patterns, Professor Shanmugaratnam started a simple card index of all histologically-diagnosed cancers in Singapore. At the time, the government’s department of pathology, where he was based, provided histology services for the whole island, making record-keeping a simple undertaking.

But not all cancers are histologically diagnosed. Other methods, such as radiology (the use of imaging techniques, including X-rays and ultrasound) are also used, especially when tumours are located in inaccessible locations such as the lung. In 1967, Professor Shanmugaratnam founded the Singapore Cancer Registry (SCR)—a nation-wide registry that would capture all cancers regardless of how they are diagnosed.

Established in NUS’s department of pathology, the SCR was initially funded by the International Agency for Research on Cancer (IARC), a World Health Organization (WHO) agency based in Lyon, France, and later by annual donations from the Singapore Cancer Society and research grants from NUS.

The SCR was the first comprehensive, population-based cancer registry in South-east Asia. Singapore, says Professor Shanmugaratnam, was an ideal country in which to establish such a registry. Even back then, there were regular censuses of the population, identity card numbers for all citizens and permanent residents, and good hospital diagnostic facilities that were easily accessible across the island. Still, the sheer amount of data posed challenges.

To ensure completeness, registration was based on information from several sources: cancer notification forms submitted by doctors, hospital discharge forms from all government hospitals, reports from all pathology departments, and death statistics from the Registrar of Deaths.

“The difficulty was that we had no computing facilities when we first started, and that made cancer registration a very difficult, time-consuming operation,” recalls Professor Shanmugaratnam. “Everything had to be done by hand.”

The SCR employed just two secretaries and one record searcher to handle its day-to-day operations. They would manually collate the data and transfer it to 80-column punch cards—a now-obsolete data entry system that involved punching holes in stiff IBM-made paper cards to encode the information. These were shipped to Lyon where they could be read and tabulated by IARC computers.

After a decade of operations, the SCR eventually acquired its own computing equipment, largely through the efforts of Chia Kee Seng and Lee Hin Peng, now professors at the NUS school of public health, who were actively involved in developing the registry. Since 1983, the SCR has published regular, detailed reports on the incidence and patterns of various cancers in Singapore. This data allows public health personnel to identify interesting or unusual trends among different ethnicities, age groups, occupations, or other demographic groups.

For example, Singapore’s three major ethnicities—Chinese, Malays and Indians—have differing cancer incidence rates: Chinese have the highest risk of developing nasopharynx, lung and colon cancers, Malays ovarian cancer, and Indians mouth cancer. Among the major Chinese dialect groups in Singapore, nasopharyngeal cancer (NPC) is more common among the Cantonese, whereas oesophageal and stomach cancers are more common among the Hokkiens and Teochews.

Patterns of cancer occurrence in Singapore have also changed over time—incidence rates for prostate cancer, colon cancer and lymphomas have risen, while incidence rates for oesophageal and stomach cancers have dropped. Understanding these trends allows high-risk groups to be targeted with screening and prevention programmes. Follow-up studies, which monitor patients over time, can also be done to assess the effectiveness of treatment regimes.

Professor Shanmugaratnam served as the SCR’s director from 1968 to 2002.

“As a pathologist my main concern was diagnostic work,” he says. “But I felt that this was important data to collect. Such information is essential for the development and evaluation of cancer control programmes.”

In 2001, the SCR, bulging with more than thirty years of data, was transferred to the Ministry of Health. It is now part of the National Registry of Diseases Office, which also comprises registries for acute myocardial infarction (heart attack), chronic kidney failure, stroke and trauma injuries. While electronic medical record systems have simplified the maintenance of disease registries, their importance has not diminished.

“Patterns of cancer are changing so rapidly that what happens in the next 10 to 15 years may not be representative of what happened before,” says Professor Shanmugaratnam.



Classifying cancers

In addition to founding the SCR, Professor Shanmugaratnam is an expert in the histopathology and epidemiology of NPC, one of the cancers affecting the upper respiratory tract. NPC caught Professor Shanmugaratnam’s attention because of its unusual disease pattern. Rare in most countries, it is one of the leading cancers in southern China and South-east Asia.

Once cancers have been diagnosed, histopathologists further classify them according to a detailed range of criteria. These include the type of tissue in which the cancer arises, how abnormal the cells of a tumour look, and the severity of the disease—whether or not it has spread to other organs, for example. Classification is not just an academic exercise; it helps doctors make a prognosis and decide on a course of treatment.

Drawing on his expertise in histopathology, Professor Shanmugaratnam was largely responsible for developing the WHO’s classification of NPC. He is the leading author of the first (1978) and second (1991) editions of the book, Histological Typing of Tumours of the Upper Respiratory Tract, and also an editor on the third edition of the book, The International Classification of Diseases for Oncology (2000).


An evolving discipline, and a lifetime of learning

Over the course of a career that has spanned almost seven decades, Professor Shanmugaratnam has seen the discipline of pathology change dramatically. While simple tissue sections and stains were the standard in the 1950s, pathologists today have access to a range of techniques, including electron microscopy, cytopathology (examining cells instead of tissues), immunohistochemistry (the use of antibodies to label cell constituents) and molecular diagnostics (detecting genetic changes in cancerous cells, for example).

Professor Shanmugaratnam still conducts fortnightly seminars for trainee doctors in the department of pathology, and consults on difficult cases referred to him by colleagues from both public and private hospitals. Keeping up with new developments in the field has thus become a deeply-ingrained habit, now facilitated by modern technology.

In his free time, Professor Shanmugaratnam enjoys reading about local history, and also listens to Indian classical music, in which he was trained. He used to play the pullankuzhal (or venu), an Indian bamboo flute.

But simply being able to do his job, he says, is what gives him the most satisfaction.

“I’m glad I have been able to continue working after retirement as a part- time consultant in the NUS department of pathology.”

And so every weekday morning, without fanfare or ceremony, Professor Shanmugaratnam arrives at his office to peer quietly down the eye-piece of his microscope, looking for the answers within.


This feature is part of a series of 25 profiles, first published as Singapore’s Scientific Pioneers. Click here to read the rest of the articles in this series.

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Copyright: Asian Scientist Magazine; Photo: Bryan van der Beek.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Shuzhen received a PhD degree from the Johns Hopkins Bloomberg School of Public Health, USA, where she studied the immune response of mosquito vectors to dengue virus.

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