INDIA – For this lump in your belly – it's probably your unborn twin.
So they told a teenager in India after surgeons removed "hairy cheese" from their belly two years ago, LiveScience reports.
More specifically, the 14-by-6-by-4-inch mass contained visible ribs and vertebrae, along with "multiple teeth and limb-like structures" when analyzed in BMJ case reports.
A 17-year-old man complained of a growing lump of the abdomen that sometimes caused her pain or a feeling of fullness. After computed tomography, doctors diagnosed her with fetus in a fetus, a rare condition in which a strangely developed fetus is found in a person's body. Why it appears is not clear.
Scientists say that an identical twin probably engulfs another during early pregnancy at Arizona State University, or a type of tumor called a teratoma consisting of body tissues such as muscles, bones, and hair.  Fewer than 200 instances have been recorded and only 7 of people aged 15 and over. In the case of the Indian teenager, the doctors successfully removed most of the mass but had to leave tissue tightly bound to the blood vessels.
This increases the chance of cancer and means that it must be checked annually. But for now, the report says it's okay: "I was very worried about my tummy," she says. "After the surgery, I feel very well … and my parents are also very happy." (Read more stories about the medical condition.)
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