Hiroto Inaba, MD, PhD, is an oncologist at St. Jude Children’s Research Hospital and the principal investigator for the Total Therapy 17 clinical trial. Dr. Inaba is also a 17th generation samurai. He will explain everything ...
I was not actually supposed to leave Japan. My family expected me, as its first son, to follow tradition, stay home and someday replace my father as head of the household. I originally planned to spend only a couple of years at St. Jude before returning to my home in the Kii Mountains, but this place has been really hard to leave.
My most famous samurai ancestor, Yoshimichi Inaba (also known as Ittestu Inaba), was born in 1515 during the Sengoku period, the “age of warring states” in which the famous movie Seven Samurai is set. Yoshimichi died in 1589, but he still works with his daimyō (samurai lord) today, as a character in a series of samurai video games.
I represent the 17th generation of my branch of the Inaba lineage after Yoshimichi, and I also lead the 17th iteration of the influential St. Jude Total Therapy protocol investigating treatments for acute lymphoblastic leukemia (ALL) and lymphoma. The two “17s” are a coincidence, and my heritage and my work also have a few things in common.
Since Yoshimichi’s day, the descendants of samurai have found new vocations, but the philosophy behind that way of life, known as bushido, is still very meaningful in Japan. In fact, I sometimes refer to my mission at St. Jude as “fighting leukemia with the samurai spirit.”
At first glance, bushido might seem too traditional or inflexible for guiding scientific research or caring for gravely ill children. I like to point out that my name, Hiroto, means flexible, contrasting with my 16th century ancestor’s nickname, Ittetsu, which actually became a Japanese word meaning stubborn or resolute, due to his character. Here in the 21st century, I must be flexible enough to incorporate new scientific findings and better methods for fighting cancer.
Flexibility had its place in bushido philosophy and in the history of samurai. In The Book of Five Rings, 17th century sword-master Musashi Miyamoto advised his readers to shift effortlessly between disciplines and options when presented with new information. Yoshimishi’s daimyō, Nobunaga Oda, was proud of his archers’ accuracy, but he did not hesitate to adopt a strange new technology called teppo (matchlock guns), imported by the Portuguese, and arm his soldiers with them.
Bushido is not only about fighting. Several of the virtues historically admired by samurai have survived in modern Japanese culture. As a pediatric oncologist, I have found that three specific virtues are helpful guides in my clinical practice.
Today we are fighting ALL and lymphoma with a new “order of battle” known as Total Therapy 17 (TOT17). It is the 17th iteration of the St. Jude Total Therapy clinical trial, which began in 1962, when Dr. Donald Pinkel introduced simultaneous, multi-drug therapy for ALL.
Through the previous 16 Total Therapy trials, we have learned how individual children respond to leukemia medications in very different ways. To reduce toxicity and the risk of adverse effects, we select doses and medications tailored for each individual child.
The objective of Total 17 is to further refine this selection process with precision medicine. Every child in the trial undergoes genomic testing of both normal tissue and leukemia cells to target the therapy. The leukemia-cell data can identify abnormal mutations that may be targetable by new drugs. If the patient does not respond well to treatment, we can add those agents to a therapy to improve the responses.
That's why my fight will not only be treating patients. My fight will include working with our researchers, my fellow clinicians and the companies with new tools we can bring to the fight, to increase survival.
We are seeing a 94% survival rate with ALL, but we still want to go to 100%. There is a way to get there. We have many things to do.