Paul Kalanithi never got to witness the impact that his first, and only, book had on the literary world.

When Breath Becomes Air was published by Random House in 2016, 10 months after Kalanithi died at the age of 37. (His widow, Lucy Kalanithi, completed the book and guided it to publication.) The memoir is an account of Kalanithi’s battle with stage 4 lung cancer, a fight that would last less than two years. As a neurosurgical resident at Stanford University, Kalanithi had experience with helping patients confront their own mortalities. When he received the diagnosis that would shatter his life, he had to confront his own.

The book was met with rave reviews, including a starred one from Kirkus, in which a critic called the book “a moving meditation on mortality by a gifted writer whose dual perspectives of physician and patient provide a singular clarity.”

It didn’t take long for the memoir to find an audience—it spent more than a year on the New York Times bestseller list and won praise from Bill Gates, who called it “the best nonfiction story I’ve read in a long time.”

The book’s success led publishers to put out others by writers grappling with their own imminent deaths, including Julie Yip-Williams, whose The Unwinding of the Miracle was also published posthumously. When Breath Becomes Air has also endured with health care professionals, who regularly push copies into the hands of medical students. It remains a popular, if heart-wrenching, book among readers touched by Kalanithi’s inspirational candor. As he writes, “Even if I’m dying, until I actually die, I am still living.”

Michael Schaub is a contributing writer.