I grew up in a house of spirituality, homeopathy, palmistry, astrology, art, and science alike. My father, with a masters degree in statistics, is a computer systems architect. He also fancies himself an amateur palm reader. The irritation with which I reluctantly used to give my hands over to my father, before the SATs, college decisions, medical school admissions, and my residency match results was real, but I was always curious.

In a crystal shop on Harvard’s campus, I came across a tattered copy of the book my father had been tracking down named, The Book of Fate & Fortune: Cheiro’s Palmistry.” I could never tell if my father believed in the palm’s ability to prognosticate, or if he enjoyed entertaining guests at parties, but Hindu mythology, including the epic Mahabharat, references examining the hands to foretell important aspects of a person’s life.

From an evolutionary perspective, it is speculated that lines on the palm persist to allow us complex micromotion without stretching the skin. Imagine when our hands are tight, swollen with fluid, the lines begin to disappear, and our dexterity decreases. This hardly explains the medical origin of variation in hand-shape, fingerprints, and handprints. We know there is genetic basis for the shape of a person’s hand, and even some of the lines found on the palm. A single palmar crease combines the head-line and the heart-line into one, which doctors and geneticists have long associated with Down Syndrome, is caused by a chromosomal abnormality. Marks may be acquired by vocation or craft. The book makes simple associations — callused and rough hands mean a patient does physical labor. Most interestingly, a person’s health is reflected in their hands.

“Hold your hands out,” I tell my patients, searching for clubbing or rounding of the digits to discern their lung function. I squeeze their fingertips to measure how long it takes for the blood to flow back into them to see how well does the heart works. I look for stains, rashes, track marks, signs of insects or scabies. I look for muscle tone and bulk, the range of motion, and any deformities suggestive of joint disease. I look for upper motor neuron function and lower motor neuron function, and other clues of neurological disease. I look for these things in the hands of my patients. I look for their past history, and I look to these signs to tell me the future of their health.

The book of Cheiro begins with a “Defense of Palmistry,” in which he states, “I am well aware that palmistry is considered quackery and humbug; but after all, facts are stubborn things, even if they do not rest on any known scientific basis … Almost all medical men admit now that the different formations of nails indicate different diseases, and that it is possible from the nails alone to predict that the subject will suffer from paralysis, consumption, heart disease, and so on. Many a well-known doctor has told me he has read more from the hand than he dared acknowledge, and that it was but the old-time prejudices which kept many a man from admitting the same thing.”

“Long nails … bluish in appearance, denote bad circulation proceeding from ill-health, or nervous prostration. This is very often the case with the hands of women between the ages of fourteen and twenty-one and forty-two and forty-seven.” Cheiro was describing Raynaud’s phenomenon, which is a spasm of the blood vessels in the hands, often manifesting in young women and results from either cold or emotional stress.

This “quack” used observation to correlate physical findings with the status of people’s health. He then applied this “methodology” to famous people’s hands who were already deceased, and for whom “outcomes” were already known. I was reminded of a common practice in oncology, where nomograms, or predictive or prognostic tools, are developed based on observations of one group, and then applied to a different group of patients to validate how well the predictive tool works. Cheiro resembled a scientific investigator. Or I resembled a palm reader.

Before Ms. Washington (name changed) ever shows up in the clinic for recommendations regarding her breast cancer, I spend hours poring over her medical chart, looking for clues about her age, her co-morbidities, any hints that will tell me how likely it is for her to die of other diseases, over her breast cancer. I think about the biology of her tumor (at least, what we think we know about the biology), to understand how it might respond to various therapies. I look at evidence and literature, and memorize the risk of recurrence, the risk of death. I put all of the numbers together, guess at her future, and then, she chooses her own treatment. She writes her own destiny.

Our genetics portend future and potential. Maybe some events come to pass, and others do not, influenced by changeable factors we do not yet understand. On a cellular level, the blueprints of our future are somehow coded into our body, in a flexible, but not fatalistic sense — we are totipotent, multipotent, and differentiated. As a radiation oncology resident, I am asked “What are my chances of cure? Of survival? Of this cancer coming back.” We have many more data points than Cheiro did to help guide patients as to what their outcomes may be, but we hide a little bit of our own palmistry in words like “positive predictive value,” “likelihood,” and “prognosis.” I am often struck by how much we cannot say with any certainty. We are all fortune tellers.

Divya Yerramilli is a radiation oncology resident.

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