Cari Romm – Doctors Found a Tiny Second Brain Growing Inside This Woman’s Tumor

Here’s a horrifying little story to kick off your weekend: A 16-year-old girl in Japan recently had a tumor surgically removed from her ovary — and when her doctors split it open, they found a tiny brain growing inside.

To be more specific, they found “clumps of greasy, matted hair inside, and a 3-centimetre-wide brain-like structure covered by a thin plate of skull bone,” New Scientist reported. In a case report published last week in the journal Neuropathology, the girl’s doctors explained that the structure turned out to be a cerebellum, the part of the brain that coordinates movement, and part of a brain stem, which connects the brain to the spine.

This particular type of tumor — the kind containing tissues normally found elsewhere in the body — is called a teratoma, Greek for “monstrous tumor,” and it’s a fairly common thing to find in the ovaries: According to New Scientist, “about one-fifth of ovarian tumours contain foreign tissue, including hair, teeth, cartilage, fat and muscle,” and, yes, brain cells. But as Japanese researcher Masayuki Shintaku, one of the report’s co-authors, told the magazine, it’s rare for those cells to create something actually resembling a human brain — and especially a brain so fully formed that it actually had functioning neurons, as this one did.

Read more