INDIA – About this knot in your stomach – it was probably your unborn twin.
A teenager in India was told after two years ago surgeons removed "hairy cheesy material" from their tummy, LiveScience reports.
More specifically, the mass of 14 by 6 by 4 inches contained apparent ribs and vertebrae, as well as "multiple teeth and structures resembling limb buds," according to an analysis in BMJ case reports.
The 17-year-old had complained of a growing abdominal lump, which sometimes caused pain or the feeling of being full. After a CT scan, the doctors diagnosed her with fetus in the fetus, a rare condition in which an abnormally developed fetus is found in a person's body. Why it occurs is unclear.
Scientists say it's probably an identical twin that absorbs another during early pregnancy, or a type of tumor called teratoma, which consists of body tissues such as muscle, bone, and hair.  There are less than 200 cases registered, and only 7 in persons 15 years and older. In the case of the Indian teenager, the doctors successfully removed most of the mass, but had to leave behind some tissue that was tightly tied to blood vessels.
This increases the risk of cancer and means it needs to be studied annually. But right now, the report says she's fine: "I was worried about my abdominal lump," she says. "I feel very well after the operation … and my parents are also very happy." (Read more about diseases.)
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