Albert C. Broders, tumor grading, and the origin of the long road to personalized cancer care

The roots of precision cancer therapy began at the Mayo Clinic in 1914 when surgical pathologist Albert C. Broders began collecting data showing that cancers of the same histologic type behaved differently. In March 1920, based upon 6 years of clinical follow-up, Broders published his first paper, utilizing data from over 500 cases of squamous cell carcinoma of the lip that he had blindly divided into four histologic grades based upon degree of differentiation, showing that numerical tumor "grading" allowed him to predict patient prognosis. Before this, surgeons had no scientific way to evaluate prognosis. Broders then replicated his work using other types of tumors at other body sites, as did several Mayo Fellows and pathologists at other institutions. Cuthbert Dukes in London, England not only replicated Broders' findings with rectal adenocarcinomas, he also used the same data to develop the first tumor "staging" methodology by focusing upon depth of local invasion and presence or absence of lymph node metastases. Soon, tumor grading, tumor staging, or the combination of both represented state-of-the-art prognostic techniques for scientific cancer care. This brief historical vignette celebrates the 100th anniversary of Broders' first paper, which is the starting point for the long road to personalized cancer care.