Vera Peters, Quiet Revolutionary

Dr. Vera PetersDr. M. Vera Peters (MD ’34), one of the Faculty of Medicine’s first female professors, made contributions that changed medicine, yet some believe she never got her due. In the 1950s, this legendary radiation oncologist demonstrated that radical mastectomies were unnecessary in most cases. And she turned Hodgkin’s lymphoma into a treatable disease with radiation therapy. Here she shows off U of T Medicine’s pioneering weapon in the war against breast cancer, the “Cobalt X-otron” bomb developed by the scientific staff of the Ontario Cancer Institute, 1958. 


By Susan Bélanger


Vera Peters (1911–1993) became the first female physician in the Faculty of Medicine to achieve worldwide scientific recognition.  She revolutionized the treatment of both breast cancer and Hodgkin lymphoma, and was committed to patient empowerment at a time when such notions were virtually unheard of. Peters accomplished all of this while raising a family, which was also highly unusual for the few women in academic medicine during the first half of the 20th century.

Like many Toronto medical graduates of her time, Mildred Vera Peters came from a modest rural background. Born into a farming family in Thistletown (now part of northwestern Toronto) she grew up milking cows and driving a tractor before school. Her mother Rebecca, however, was a teacher who encouraged her five children to pursue higher education. All but one completed university; Vera, the youngest, proved to be the brightest and most determined. She graduated from U of T’s Faculty of Medicine in 1934, one of only 10 women in a class of 115.

Vera Peters. Torontonensis, 1934Vera Peters. Torontonensis, 1934

Peters’ energy and ambition are already apparent in her yearbook entry, with its long list of extracurricular activities. Still identified here under her full name, she soon did away with “Mildred” and was known professionally as “Dr. M. Vera Peters”.

While Peters was in medical school her mother was diagnosed with breast cancer and underwent a radical Halstead mastectomy. When her cancer metastasized, Gordon Richards, the Faculty’s first head of Radiology, attempted to save her with a vest implanted with radium needles. The treatment was unsuccessful, but inspired Peters to train as a radiation therapist under Richards’ tutelage. In 1937 she joined the full-time staff of the Toronto General Hospital’s radiotherapy service, becoming one of the first women to hold a clinical appointment in a Toronto teaching hospital.

Hodgkin’s Disease: potentially curable

During the early years of Peters’ career Hodgkin’s Lymphoma was considered universally fatal. Yet by 1947 some Toronto patients were still alive a decade after receiving radiation treatment.  Gordon Richards asked her to investigate. Peters did her clinical work during the day, and after dinner each night she lit a cigarette, poured a cup of coffee and plotted each patient’s data on large sheets of graph paper. After two years of late nights she became the first investigator to show that early-stage Hodgkin’s was potentially curable with radiation therapy. This landmark study — which launched Peters’ international research career — was published in 1950 in the American Journal of Roentgenology and Radiation Therapy. 

Unfortunately Richards died of leukemia (a common disease among pioneer radiologists) before the paper was published. But he survived long enough to watch his protégée present her findings at a TGH staff meeting in early 1949.

Cancer treatment in Toronto took a giant stride forward with the establishment in 1958 of the Ontario Cancer Institute and its clinical facility, the Princess Margaret Hospital. Led by pioneer medical physicist Harold Johns, OCI’s scientific staff developed powerful radioisotope-based devices such as the “Cobalt X-otron” bomb, which could target deep tumours without damaging the skin.

Portrait of M. Vera Peters c.1970sOfficial portrait of M. Vera Peters, undated but 1970s; widely reproduced

Breast Cancer: revolutionary conservatism

Peters continued to study Hodgkin’s throughout her career. Yet she remained keenly aware of the physical disfigurement and psychological devastation caused by radical mastectomy, and improving breast cancer treatment became her lifelong passion. During the 1960s and 70s Peters went back to her meticulous charting of patient records from PMH and its predecessor the Radiotherapy Institute. In 1975 she published the first controlled study to demonstrate that outcomes from wedge resection (“lumpectomy”) and radiation were equal to or better than more invasive procedures. “Mastectomy could, with few exceptions, be eliminated in early breast cancer,” adding, “This study shows … that radical methods are not in the best interests of the patients.”

This conservative approach was in line with a long-standing Toronto tradition of organ-sparring cancer treatments, yet was vigorously opposed elsewhere. “I was refuted and shunned by most of the outstanding surgeons in the States,” Peters recalled a few years later. The Canadian medical establishment, while (predictably) quieter in their opposition, was likewise skeptical. Peters’ retrospective studies were criticized as inferior to the emerging “gold standard” of prospective randomized trials. But she rejected random sampling on the grounds that no woman should undergo an unchosen mastectomy, and PMH stayed out of these trials. It wasn’t until 2002 that the conservative approach to early-stage breast cancer was officially endorsed, after two large prospective studies confirmed her findings.

Vera Peters always involved her patients in treatment decisions, a heretical idea during an era when doctors’ orders held sway. Patients adored her for her warmth and empathy. These qualities, along with her quiet determination, shone as well in her personal life. Peters became an important role model for women in academic medicine by successfully juggling the multiple demands of career and family — so successfully indeed that her younger daughter Jenny (Lobb) Ingram became a physician as well.

Unfortunately Peters’ quiet, unassuming manner also worked to her disadvantage in the aggressive, male-dominated world of international medical research. Her contributions to both Hodgkin’s and breast cancer research took longer to gain general acceptance than they otherwise might have done. In daughter Jenny’s words, “she was not a strong speaker” and “hated arguing.” In the absence of more outspoken advocacy, her findings on Hodgkin’s disease didn’t appear in the major medical textbook Harrison’s Principles of Internal Medicine until the 1974 edition, while the quarrel over breast cancer treatment dragged on until the end of the century.

Yet following her retirement from PMH in 1976, Peters began to receive recognition both in Canada and internationally. In 1976 she was invested as a member of the Order of Canada, and promoted two years later to the rank of Officer.

Peters’ favourite awards were those from her own profession. In 1977 she received the Antoine Béclère Award from the Radiological Society of France, the first woman to be so honoured. Two years later, she traveled to New Orleans with her two daughters to receive the medal of the American Society for Therapeutic Radiologists (now the American Society for Radiation Oncology), the leading association in her specialty.

A greater appreciation of Vera Peters’ contributions has emerged in recent years, with the rise of patient-centred care and the vindication of her conservative approach to cancer treatment. Peters was inducted into the Canadian Medical Hall of Fame in 2010, and in 2014 her struggle to reform breast cancer treatment was celebrated in the play Radical by Toronto oncology professor Charles Hayter.