What Stephen Jay Gould's Story Can Help Us Understand About Mesothelioma — and Statistics

An essay written from a hospital library

In his 1985 Discover essay, the paleontologist Stephen Jay Gould opened with a date. "In July 1982, I learned that I was suffering from abdominal mesothelioma, a rare and serious cancer usually associated with exposure to asbestos."

He asked his doctor what the best medical literature on it was. She told him there was nothing really worth reading. He went to Harvard's medical library anyway and found the number she had spared him: a median mortality of eight months after discovery.

Then he did something useful with it. The essay he wrote, "The Median Isn't the Message," is still handed to people who have just been given a number.

The Harvard Gazette reported that Gould died on the morning of May 20, 2002, in Manhattan, of metastasized lung cancer. He was 60. That is a different disease from the mesothelioma he wrote about, and nearly twenty years separated the two.

What he got right about the number

Gould's argument is short, and it holds.

A median is the halfway point. Half the group is above it, half below. It is not a prediction, and it is not the same as a mean, which is the total divided by the number of people.

His second point is the one that matters more. Survival data is skewed. Nobody survives less than zero months, so the left side of the distribution is squeezed against a wall. The right side has no wall at all. It stretches out for years.

So the middle of a survival curve sits much closer to the bad end than most people assume. Being on the right half is not a rare escape. It is half of everyone.

He also noted what a distribution is attached to. His applied to survival with mesothelioma under the treatment of that time. He entered an experimental protocol. When the treatment changes, the distribution can change too.

Our pages on what a five-year survival rate actually means and on median survival work through the same arithmetic.

The cancer itself

This cancer starts in the mesothelium, the thin membrane lining the chest and the belly. NCI calls it a relatively rare cancer of those linings.

Gould's was peritoneal, meaning it began in the lining of the abdomen. The other main site is the pleura, the lining around the lungs.

Asbestos is behind most of it. NCI states that IARC found clear evidence that asbestos causes this cancer, along with cancers of the lung, larynx and ovary. NCI adds that most cases are thought to come from asbestos. Its summary for doctors puts a known history of asbestos exposure at about 70 to 80 percent of cases.

Fluid build-up is the main practical problem. NCI reports that such fluid, called an effusion, is a major symptom for at least 66 percent of patients.

When to get checked

NCI lists the signs. Any of these, especially with a history of asbestos exposure, is a reason for an appointment.

• Trouble breathing.
• A cough that persists.
• Pain under the rib cage.
• Pain or swelling in the abdomen.
• Lumps in the abdomen.
• Constipation.
• Blood clots forming when they should not.
• Weight loss for no known reason.
• Fatigue.

There is no screening test for this cancer in the general public. Past exposure to asbestos belongs in your written medical history. The gap between exposure and disease can run for decades. Our page on asbestos exposure and cancer risk covers who was most often exposed.

How it is diagnosed and treated

Work-up starts with a chest x-ray and a CT scan. A biopsy of the pleura or the peritoneum confirms it. NCI lists five routes to that tissue: needle biopsy, thoracoscopy, thoracotomy, peritoneoscopy and open biopsy.

In the chest, surgery can mean wide local excision. It can mean pleurectomy and decortication, which strips the lining off the lung. The largest option is extrapleural pneumonectomy, which takes a whole lung with the chest lining, the diaphragm and the sac around the heart.

Pleurodesis is different. It seals the space so fluid stops coming back.

For disease in the belly, NCI describes HIPEC, short for hyperthermic intraperitoneal chemotherapy. The surgeon removes all the cancer that can be seen. Then a heated drug solution is pumped through the belly.

Radiation, systemic chemotherapy and immunotherapy also have roles. Our page on mesothelioma goes through the options by stage.

What this does not mean

Gould's twenty years are not a forecast. NCI lists what the outlook actually turns on. Stage. Tumor size. Whether surgery can remove it all. How much fluid there is. Age, activity level, and how the heart and lungs are working. How the cells look under a microscope. White cell count and hemoglobin. And sex.

Nor is his essay an argument that numbers do not matter. He went and found his. The argument is about reading them correctly.

One more thing is worth saying plainly. The eight-month median he read in 1982 came from the literature of that time. It described a group treated with the tools then available. It never described him, and it does not describe anyone today.

Sources

• Stephen Jay Gould, The Median Isn't the Message, Discover, June 1985 — https://www.stat.berkeley.edu/~rice/Stat2/GouldCancer.html
• Harvard Gazette, Stephen Jay Gould dies at 60 — https://news.harvard.edu/gazette/story/2002/05/stephen-jay-gould-dies-at-60/
• NCI, Mesothelioma Symptoms — https://www.cancer.gov/types/mesothelioma/symptoms
• NCI, Mesothelioma Diagnosis and Prognosis — https://www.cancer.gov/types/mesothelioma/diagnosis-prognosis
• NCI, Mesothelioma Treatment — https://www.cancer.gov/types/mesothelioma/patient/mesothelioma-treatment-pdq
• NCI PDQ, Malignant Mesothelioma Treatment (Health Professional Version) — https://www.cancer.gov/types/mesothelioma/hp/mesothelioma-treatment-pdq
• NCI, Asbestos Exposure and Cancer Risk — https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/asbestos/asbestos-fact-sheet

How this article was prepared

An AI-assisted editorial system helped prepare this page. No named medical reviewer has reviewed it unless one is listed.

The National Cancer Information Foundation publishes Cancer Explained. This page is for learning. It is not medical advice and does not suggest a test or treatment.

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