It's a "meet cute" story as old as time: man ingests tapeworm, tapeworm grows to alarming sizes inside the man's digestive system, tapeworm begins having uncontrollable DNA errors leading to malignant cancers, man's weakened immune system allows these tapeworm tumors to spread throughout his body, everyone dies of tapeworm cancer. That's what happened to a Colombian man this month when he went to the hospital with a fever and cough, and experiencing sudden weight loss.

This image from the CDC shows the tapeworm cancer cells in the tumor from the Colombian patient. You could probably just tell from looking, though, right?

The doctors ran scans on the man and discovered tumors in his lungs and lymph nodes. When the doctors in Colombia did a biopsy on the tumors, they found really weird cells. Upon closer examination, the cells were rapidly multiplying and clumping just like cancer cells, but they were about 1/10 the size of human cells. Doctors also found actual, live tapeworms in the tumor, which is not usually where tapeworms live.

An H. Nana egg, H. Nana adults, and an H. Nana head(ish thing).
Sources: LiveScience