When my mother was diagnosed with carcinoid cancer in 2005, when she was 49, it came as a lightning shock. Her mother, at 76, had yet to go gray, and her mother's mother, at 95, was still playing bingo in her nursing home. My mother had always been, despite her diminutive frame, a titanic and irrepressible force of vitality and love. She had given birth to me and my nine younger siblings, and juggled kids, home and my father's medical practice with humor and grace for three decades. She swam three times a week in the early mornings, ate healthily and never smoked.

And...