Why Cancer Attacks Some Tissues—And Not Others

Why do virtually all men over the age of 90 develop some amount of prostate cancer whereas heart cancer is practically unheard of?

The human heart rarely develops cancer, but in men that live to the age of 90, the prostate gland almost invariably develops some cancer. Why should this be the case?


According to Harold Varmus, the Director of the National Cancer Institute, we should be focusing more research on why some tissues are especially vulnerable to cancers while others are practically immune. "The remarkable variation, not just among organs, but among organ types in different environmental settings and locations, represents one of the great challenges that I don’t think the cancer community has completely grappled with yet," he says during Big Think's Breakthroughs: Cancer panel. "This is an area of provocative research that we ought to be paying more attention to now that we have better tools for looking at genetics."

The small intestine is another cancer-resistant organ: "We’re all born with 25 feet of small intestine, yet we see fewer than 5,000 cases a year in the United States," says medical oncologist Deborah Schrag. Compare that with the large intestine: there are just 6 to 9 feet of large bowel, including the colon, yet over 150,000 cancer cases per year—30 times more than the small intestine. This is all the more baffling because, molecularly, the cells of the small and large intestine are pretty similar. The large bowel cells are slightly more involved in reabsorbing water than nutrients, but that alone shouldn't account for the dramatic difference, says Schrag. 

The secret could lie not in the cells themselves but in the microorganisms that exist alongside those cells. Studying the carcinogenic role of microorganisms is a very interesting new theme in cancer research, says Varmus. "The large intestine has trillions of bacteria and the small intestine has much less," he says. "It may well be that this is a driver of oncogenic change." 

More Resources:

Information on the Human Microbiome Project, an attempt to map all the microorganisms living in the body that could contribute to diseases like cancer.

The views expressed here are solely those of the participants, and do not represent the views of Big Think or its sponsors.

'Upstreamism': Your zip code affects your health as much as genetics

Upstreamism advocate Rishi Manchanda calls us to understand health not as a "personal responsibility" but a "common good."

Sponsored by Northwell Health
  • Upstreamism tasks health care professionals to combat unhealthy social and cultural influences that exist outside — or upstream — of medical facilities.
  • Patients from low-income neighborhoods are most at risk of negative health impacts.
  • Thankfully, health care professionals are not alone. Upstreamism is increasingly part of our cultural consciousness.
Keep reading Show less

In U.S. first, drug company faces criminal charges for distributing opioids

It marks a major shift in the government's battle against the opioid crisis.

George Frey/Bloomberg via Getty Images
Politics & Current Affairs
  • The nation's sixth-largest drug distributor is facing criminal charges related to failing to report suspicious drug orders, among other things.
  • It marks the first time a drug company has faced criminal charges for distributing opioids.
  • Since 1997, nearly 222,000 Americans have died from prescription opioids, partly thanks to unethical doctors who abuse the system.
Keep reading Show less

Following sex, some men have unexpected feelings – study

A new study shows that some men's reaction to sex is not what you'd expect, resulting in a condition previously observed in women.

Credit: Pixabay
Sex & Relationships
  • A new study shows men's feelings after sex can be complex.
  • Some men reportedly get sad and upset.
  • The condition affected 41% of men in the study
Keep reading Show less

Calling out Cersei Lannister: Elizabeth Warren reviews Game of Thrones

The real Game of Thrones might be who best leverages the hit HBO show to shape political narratives.

Photo credit: Mario Tama / Getty Images
Politics & Current Affairs
  • Sen. Elizabeth Warren argues that Game of Thrones is primarily about women in her review of the wildly popular HBO show.
  • Warren also touches on other parallels between the show and our modern world, such as inequality, political favoritism of the elite, and the dire impact of different leadership styles on the lives of the people.
  • Her review serves as another example of using Game of Thrones as a political analogy and a tool for framing political narratives.
Keep reading Show less