W. Thomas London, 85, of Wyncote, a leading Fox Chase Cancer Center researcher whose work with colleagues led to the development of the hepatitis B vaccine, died Saturday, June 3, after suffering a heart attack at Abington Hospital–Jefferson Health.

An internist and endocrinologist, Dr. London was among the pioneering scientists who made an important connection between a viral antigen and hepatitis B in the 1960s. The scientists then found a link between chronic hepatitis B infection and liver cancer, and conducted research that contributed to the development of the hepatitis B vaccine in 1969, preventing many who were vaccinated from contracting the disease.

"Infection with the hepatitis B virus is preventable" with a vaccine, Dr. London told United Press International in May 1983. "We think infants born to mother carriers are at the highest risk of developing liver cancer. It's obvious that this early time in life is the time to focus primary prevention."

To that end, Dr. London sponsored vaccination efforts here and overseas. "He developed a big vaccination program in the tri-state area," said a daughter, Barbara L. Almario.

Dr. London spent the bulk of his career at Fox Chase Cancer Center. He was recruited in 1966 from the National Institutes of Health by his mentor and colleague, the Nobel laureate Baruch "Barry" Blumberg, discoverer of the hepatitis B virus. The two did further study on the virus, developed a blood test to detect the infection, and then worked on the vaccine.

The collaboration resulted in 265 publications in medical journals describing their work.

In the late 1970s, Dr. London founded the Liver Cancer Prevention Program at Fox Chase and ran it for two decades. He chaired Fox Chase's Institutional Review Board starting in 1988, and directed a division of the cancer center delving into population science studies. He also did clinical work, caring for those living with chronic liver disease.

"Tom's work in studying the pathogenesis, diagnosis, prevention and treatment of viral-related liver cancer earned him international recognition," said Fox Chase in a Tuesday statement announcing his death. "His long-term collaboration with Barry Blumberg led to breakthrough studies of hepatitis B and its link to primary liver cancer."

In 1992, Dr. London studied the case histories of 90,000 patients in Haimen city, China, and 19,000 in Senegal to pinpoint the factors that led to a high risk of liver cancer in both places. He found chronic infection with the hepatitis B virus to be the major risk factor, according to the Washington State University Department of Global Health, which studies disease control priorities.

Later, Dr. London served as vice president of the board of the Hepatitis B Foundation and its research arm, the Baruch S. Blumberg Institute. On Oct. 1, 2015, the Blumberg Institute announced the endowment of a professorship in his name. Five days later, hepatitis B researcher Ju-Tao Guo was named as the first occupant of the chair.

"For more than a half-century, Dr. London has represented the very best in a doctor and scientist – sincere compassion and outstanding research to advance the cause of and cure for hepatitis B infection," said Timothy Block, president and co-founder of the foundation and the institute. "The W. Thomas London Distinguished Professorship is imbued with a legacy of scientific integrity and achievement that will inspire the occupants of the chair for generations to come."

Although Dr. London retired from Fox Chase in 2009, he remained a foundation adviser and board member, retiring from the board only a week before he died.

Born and reared in Perth Amboy, N.J., he graduated from Perth Amboy High School in 1949. He earned a bachelor of science degree from Oberlin College and a medical degree from Cornell University Medical College. From 1962 to 1966, he served in the Public Health Service at the National Institutes of Health.

He was an elected member of the American Association for the Advancement of Science, a founder of the American Society of Preventive Oncology, and an editor of several scientific journals.

Despite his achievements, he never talked much about his professional life. "He was modest and humble to a fault," his family said.

Dr. London approached his avocations in the same methodical and self-directed way that he pursued science. He loved organic gardening, and was famous in his Wyncote neighborhood for growing the first crocuses to bloom each spring.  "He spent happy hours every winter ordering bulbs from Holland," his family said.

An avid reader of political science and the history of the natural sciences, Dr. London taught several classes at the Cheltenham Township Adult School (CTAS) on topics relating to science and disease.

He also served on the board of CTAS for four decades, and was president for one term. He took his first yoga class there in the late 1970s, and made it part of his daily routine for the next four decades.

Dr. London was a generous supporter of Oberlin and booster of Perth Amboy High, which in 1994 inducted him into its Hall of Fame.  "All his life, he effusively promoted the many charms of his hometown," his family said. He liked to wear a T-shirt that read: "It all started in Perth Amboy."

Besides his daughter, he is survived by his wife of 60 years, Linda G.; children Katharine, Emily and Nancy; eight grandchildren; and a sister.

A memorial service will be held at 2 p.m. Thursday, June 8, at Goldsteins' Rosenberg's Raphael Sacks, 6410 N. Broad St. He donated his body to science.

Contributions in his memory may be made to the Hepatitis B Foundation, 3805 Old Easton Rd., Doylestown, Pa. 18902 or via www.hepb.org; or to the Cheltenham Township Adult School, 500 Rices Mill Rd., Wyncote, Pa. 19095, via cheltenhamtownshipadultschool.org.