Breast cancer drugs could be used to shrink liver tumours in rare bile duct cancer following successful trial in Japan

A combination of non-chemo breast cancer drugs could soon be used to treat patients with a rare form of liver cancer.

Tucatinib and trastuzumab – when used together – were shown to shrink tumours in patients with bile duct cancer.

The cancer affects tubes in the liver that carry bile, which helps the body digest food by breaking down fat, and there are few effective treatments.

For those whose cancer has not spread beyond the bile ducts, the five-year survival rate is about 20 per cent – but once it spreads this drops to just two per cent.

Researchers in the pioneering trial in Japan used the two drugs to treat patients with a variety of tumours linked to a protein in the body called human epidermal growth factor receptor 2, or HER2. 

Tucatinib and trastuzumab – when used together – were shown to shrink tumours in patients with bile duct cancer (Stock Image) 

Tumours with high levels of HER2 are more likely to spread quickly through the body. Tucatinib and trastuzumab are already used to treat HER2-positive breast cancer patients.

The tablets are more effective than traditional chemotherapy and have fewer side effects.

The trial concluded that bile duct cancer had the strongest response to the medicines, with nearly half seeing their tumours shrink.

Every year in Britain some 2,700 people are diagnosed with bile duct cancer, also known as cholangiocarcinoma. Cases have doubled in the past two decades, but the reason for this is unknown.

Experts say tucatinib and trastuzumab should now be offered to bile duct cancer patients who have failed to respond to existing treatments.

‘This chemotherapy-free combination was shown to be safe and well tolerated,’ said Dr Yoshiaki Nakamura, oncologist at the National Cancer Centre Hospital East, in Kashiwa.