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Dr. Paul G. Walfish: Fifty years of advancing thyroid cancer care

Amazing research discoveries that impact patient care are taking place at Mount Sinai Hospital.

This episode focuses on the groundbreaking research of Dr. Paul Walfish in thyroid cancer and how his work has impacted Katherine, a patient of his since 2003.

"I feel very fortunate
to be under the care of
a physician/scientist
who is on the
cutting edge
of medicine."
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Katherine Newman

Photo courtesy of Christopher Strube/Dolce Media Group

After receiving surgery for thyroid cancer, Katherine was referred to Dr. Paul Walfish in 2003 to help manage the ongoing screening and care she required. She had a complex history which included thyroid cancer as well as two different skin cancers - melanoma and squamous cell carcinoma . “As a result of my health history, I had an international network of specialists with whom I would consult regularly about my care decisions,” says Katherine. “They all referred to Dr. Walfish by first name, were familiar with his work and had profound respect for him. It was very reassuring.”

Katherine recalls one of the many instances where Dr. Walfish’s research and expertise impacted her care. “He wanted to use a radiation dose that was significantly lower than the standard at the time, as he felt the larger dose could contribute to other cancers down the road,” explains Katherine. “While I was cautious with that approach at first, the fact that I knew he was a leading authority in thyroid cancer made it only natural that I would defer to him. In the end, the lower dose actually ended up becoming the new standard of care for thyroid cancer treatment.”

As an academic health sciences centre, many of Mount Sinai’s clinicians are also researchers, a fact that can provide additional assurance for patients, as it did for Katherine. “I feel very fortunate to be under the care of a physician/scientist who is on the cutting edge of medicine,” she says. There are other instances she recalls where his expertise prompted him to make decisions that had a significant impact on her quality of life, allowing her to avoid debilitating treatments and lengthy hospital stays. “He personalized the treatment for me, taking into account my unique history, my lifestyle and his understanding of my prognosis. I can’t imagine getting better care for thyroid cancer from anyone else.”

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As a pioneer in the treatment of thyroid disease, Dr. Paul Walfish has made significant contributions to medical science and clinical care on a global scale. With more than 250 publications in the world literature, his prolific career at Mount Sinai Hospital – now in its 50th year – has helped put the Hospital on the map as a leader in the field of head and neck diseases, including thyroid cancer. Though his accomplishments are many, Dr. Walfish remains deeply committed to exploring new questions and finding innovative strategies to improve the lives of those touched by thyroid disease.

Dr. Walfish has been a game-changer in the field of thyroid cancer. In 1965, after establishing the Nuclear Medicine Department at Mount Sinai, he and his colleagues at Mount Sinai pioneered studies in North America using fine needle biopsy and ultrasound technology on thyroid nodules for the early detection of thyroid cancer. They also made an important discovery that large, fluid-filled thyroid nodules, previously believed to carry less than a two per cent risk of cancer, actually carried a 30 to 40 per cent risk. In addition, Dr. Walfish pioneered a new testing method that can determine whether radioactive iodine treatment is required following thyroid cancer surgery. These new techniques armed clinicians with enhanced tools and knowledge, essentially revolutionizing the management and treatment of thyroid cancer in North America.

Most recently, working together with colleague Dr. Ranju Ralhan at Mount Sinai, the duo identified a tissue biomarker that can help predict whether certain patients will develop oral cancer. “We are extremely pleased to have identified a protein that can predict which oral lesions will transform into cancer,” says Dr. Walfish. “This will be a great tool to determine which patients will require closer follow-up, and in time will lead to improved patient survival.” The team is continuing to explore the identification of biomarkers for other cancers, including breast, prostate and thyroid.

Dr. Walfish’s many discoveries have not only reshaped clinical care at Mount Sinai Hospital, but they have also had international impact. As a clinician and researcher, he exemplifies how the research conducted within a hospital setting makes its way to the patient’s bedside, with innovative approaches to treatment and care.

Dr. Paul G. Walfish (right) receiving the Queen Elizabeth II Diamond Jubilee Medal from Peter Mansbridge

Read about some of Dr. Walfish’s groundbreaking discoveries in thyroid disease »

Dr. Paul Walfish’s groundbreaking discoveries in thyroid disease


•  Pioneered the application of fine needle biopsy and ultrasound technique in North America for the early detection of thyroid cancer. This has helped many patients with benign nodules avoid surgery and has become the gold standard for testing thyroid nodules.

•  Discovered that certain large, fluid-filled thyroid nodules previously believed to carry less than a two per cent risk of cancer, actually carry a 30 per cent risk.

•  Pioneered the use of biomarker (a protein in the blood) – called thyroglobulin – to determine which patients require radioactive iodine treatment after thyroid cancer surgery. This discovery has achieved a new standard of care that helps patients with low-risk thyroid cancer avoid unnecessary exposure to radiation and its potential side effects, as well as the inconvenience and anxiety of the associated dietary preparation and subsequent hospital stay.

•  Pioneered the development of a newborn screening program in Ontario to detect congenital hypothyroidism, a feat that resulted in Dr. Walfish receiving both the Order of Canada and the Order of Ontario. If left untreated before one month of age, congenital hypothyroidism can lead to severe brain damage resulting in mental disability and growth failure. This screening test is now in practice in all developed countries worldwide.

•  Discovered a temporary disturbance of thyroid function in six to eight per cent of mothers after delivery and documented the autoimmune nature of this condition, which is now recognized worldwide as the Postpartum Painless Thyroiditis Syndrome.

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From the research bench to the patient’s bedside, Dr. Paul Walfish has contributed significantly to scientific knowledge that will continue to inform clinical decision-making for thyroid diseases and impact the lives of patients like Katherine.

Dr. Paul Walfish is the Alex and Simona Shnaider Research Chair in Thyroid Oncology. He is also the Director of Mount Sinai’s Alex and Simona Shnaider Research Laboratory in Molecular Oncology, and Senior Consultant at The Joseph & Mildred Sonshine Family Centre for Head and Neck Diseases. Under the direct supervision of Dr. Ian Witterick and in collaboration with Drs. Jeremy Freeman and Paul Walfish, The Sonshine Centre is at the forefront of research and applies the latest advances in diagnosis and treatment for its patients.

The annual Da Vinci Gala raises funds to support the operational costs of The Joseph & Mildred Sonshine Family Centre for Head and Neck Diseases and the Alex and Simona Shnaider Research Laboratory in Molecular Oncology.