Though the idea might make you squirm, some tumours really can grow their own body parts – or at least fragments of them.
These peculiar formations, called teratomas, arise from germ cells, which have the remarkable ability to transform into any type of tissue.
Normally, germ cells develop into sperm or eggs, but when their growth veers off course, they can form disordered clusters of tissue.
The name ‘teratoma’ comes from the Greek word teras, meaning ‘monster’, and it’s fitting.
These tumours can contain an astonishing mix of things, from hair and teeth to muscle and even organ-like structures, such as thyroid glands or eyes.
Fully functional organs are extremely rare, but the complexity of these tumours is undeniable.
Teratomas are most frequently found in the ovaries or testes, but can also appear in midline areas of the body, such as the mediastinum (the area of your chest that holds your heart) or the base of the spine.
While the majority of teratomas are benign and easily removed, a small proportion – especially those in men – can become malignant and require urgent treatment. Surgery is the primary approach for managing these tumours and the prognosis is usually positive.
Beyond their medical challenges, teratomas have provided valuable insights into the science of cell development.
Because they can include tissues derived from all three layers of reproductive ‘germ’ cells, they serve as a fascinating model for studying how cells differentiate and organise themselves.
So, can tumours grow organs? In a way, yes. But these structures are often dysfunctional and haphazardly assembled.
Teratomas are a striking, if unsettling, example of the strange and unpredictable nature of human biology.
This article is an answer to the question (asked by Anisa Manning, Stevenage) 'Can tumours grow their own organs?'
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