A Tapeworm Actually Gave Someone Its Cancer

It’s a weird story, a gross story, and a sad one, too. In addition to all the things that doctors say might potentially cause cancer in humans, we can now add tapeworm to the list.

HIV-Positive Patient Presents Strange Symptoms

A 41-year-old man in Colombia had been diagnosed as HIV-positive for seven years before seeking medical help for severe symptoms including fatigue, fever, cough, and weight loss that had been plaguing him for several months. The man couldn’t afford his HIV medication and was also found to be riddled with dwarf tapeworms, also called by their scientific name of Hymenolepis nana.

These tapeworms can grow up to an inch and a half long, but they don’t usually cause symptoms in most people. They’re extremely common, with as many as 75 million people carrying entire colonies of these parasites without ever noticing.

According to the CDC, people are infected with this parasite when they unknowingly ingest food that’s been contaminated with mouse droppings or insects, or by accidentally ingesting feces particles from someone else who is infected. All of those infection methods are shockingly commonplace, no matter where you live.

But tapeworms like these shouldn’t have caused this man’s symptoms, so doctors looked for other causes. Then they found that his lungs and lymph nodes were covered in miniscule little tumors. The doctors were completely baffled.

Man Diagnosed with Tapeworm Cancer Dies

The CDC released a statement saying that “The tumors looked similar to a human cancer, but initial CDC lab studies revealed the cancer-like cells were not human.” So either their patient was some kind of alien, or something non-human was causing this man’s cancer.

At first they considered that it could be an unusual symptom of slime mold in the sick man’s lungs, exacerbated by his HIV-compromised immune system. But while they scrambled for answers and a solution to the man’s cancer, his health sharply declined and he died.

After further analysis on the now deceased man’s mysterious lung tumors, researchers found that the DNA in the cancerous cells matched those of the tapeworms. They determined that the cause of the man’s non-human cancer was the non-human life living inside him.

This is the first documented case of a human ever being infected by cancer from a parasite. While there are some types of bacteria and strains of virus that can cause cancer in a human (the human papillomavirus or Helicobacter pylori bacteria, for example) but it’s still relatively rare. And a cancer caused by a parasite was previously unheard of. No one knew for sure that a tapeworm could even get cancer!

Although Rare, Doctors Continue Research on Cancer-Causing Tapeworms

Dr. Atis Muehlenbachs, a pathologist at the Centers for Disease Control and Prevention said in a report that although this strange case of cancer-via-parasite is “rare,” it merits further investigation because according to Muehlenbachs, “…this tapeworm is found worldwide and millions of people globally suffer from conditions like HIV that weaken their immune system. So there may be more cases that are unrecognized. It’s definitely an area that deserves more study.”

Although parasites like the dwarf tapeworm can be easily treatable with the proper treatments, it’s not yet determined whether or not the cancerous tumors transmitted from the parasites is treatable with the same medications. Chemotherapy is a possibility, but researchers still can’t be sure that it’d eliminate the parasitic-caused tumors.

Because such a bizarre medical case is rare, doctors and researchers agree that this kind of cancer could have infected humans before, but it previously went undiagnosed and undocumented. Now that they know a human host getting cancer from their parasitic hitchhikers is a possibility, they hope to raise awareness about the odd diagnosis and further explore potential cures and treatments.