Mini organs grown from tumours predict patient chemo response

Structures grown from patient's tumour cells can help identify which patients will benefit from chemotherapy drugs, according to a new study.

Scientists at the Netherlands Cancer Institute were investigating the response of metastatic colorectal cancers to the chemotherapy drug irinotecan. Irinotecan can be lifesaving but causes severe side effects including hair loss, diarrhoea and fatigue, and not all patients derive any benefit. The researchers used organoids to predict which cancers would respond to the treatment.

'This means that organoids can help improve decision-making on the best treatment options,' said lead author Salo Ooft.

The researchers hypothesised that if the drug could kill cells in the organoid, this would be a good predictor of success in attacking cancer in the patient. They used cells biopsied from 61 patient tumours to grow the organoids in the lab and were successful in growing these 3D tissue cultures from 35 of the samples.   

After studying the response of the organoids to irinotecan, 80 percent of the predicted patient responses were correct. Importantly, they correctly predicted all the patients who would benefit from the drug. 

'The latter is very important as you don't want to deny patients treatment that could have prolonged their life,' said Ooft.

The team's method for developing and screening organoids took only 21 days, compared with two to six months from earlier methodologies. 

However, the technique had some limitations. The organoid technique was unsuccessful in predicting the patient's response to a combination therapy consisting of 5-fluorouracil and oxaliplatin. The team believes that this is because factors such as the patient's immune system play a role, which cannot be tested with an organoid.