Girl, 13, managed to conceal the 'rugby ball-sized' growth for eight months

A 13-year-old girl had a rugby ball-sized tumour removed from her breast that she had concealed for eight months.

The teenager arrived at a clinic in Wales with a huge mass on her left breast, which had begun to grow as her began puberty. 

In the previous eight weeks, the tumour had grown drastically, she told doctors describing her case in the journal BMJ Case Reports.

They noted an ‘enormous rugby ball sized mass’ in her breast, measuring 35cm long and 20 cm wide.

‘Despite the enormity of the lesion, the patient managed to keep it concealed from her parents for eight months,’ they added.

Incredibly, she also kept the tumour hidden while attending school.

Suspecting it was a soft tissue cancer known as a sarcoma, doctors immediately they carried out blood tests, X-rays, biopsies and ultrasounds.

But when the tests ruled out cancer, she was diagnosed with pseudoangiomatous stromal hyperplasia (PASH).

This is a benign tumour, caused by an overgrowth of soft tissue cells.

It was decided that because of the size of the tumour, it would need to be removed surgically.

But doctors worried how much salvageable breast tissue would remain, and whether this would disrupt the breast developing normally.

Despite the girl and her family being made aware of these issues, she still decided to have it removed.

During the procedure, two tumours with a total weight of 2.7kg (6lbs) were removed, and doctors managed to preserve her breast tissue.

She recovered well, aside from some discharge from the scar on her breast.

More than a year after the procedure, scans showed her breast was developing well.

Doctors believe this case is the largest tumour of its kind in a child.

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