What is the author's style in The Emperor of All Maladies: A Biography of Cancer by Siddhartha Mukherjee?

Mukherjee describes the immersive training program as being so intensive that nothing outside of the hospital exists for the trainees. Residents eat, sleep and breathe medicine. One member of the hospital staff warned Mukherjee that he had to have a life outside the hospital or he would never make it. Rates for burned out doctors were very high. During this time, Mukherjee began to wonder about the age of cancer. This curiosity led to the writing of The Emperor of all Maladies: a Biography of Cancer.