Cancer Extraction, Tumor Reconstruction, In Vitro Testing – Personalized Cancer Treatment Scientists have created laboratory-grown “miniature tumors” to test responses to different therapies. The study involved taking tumor samples (biopsies) from 71 people with advanced bowel or stomach cancer that had spread to other parts of the body and who had tried many other cancer treatments. The researchers used these samples to grow miniature replica tumors in the lab and then tested different anti-cancer drugs on them, wanting to see if the replica tumors responded in the same way as human tumors. Ultimately, they found that the miniature tumors responded so accurately that they could predict which cancer treatments would and would not work, and that identifying in advance which treatments were likely to be effective could save valuable time and improve the outlook for cancer patients. These findings could open up a whole new field of personalized cancer treatments, but the research is still in its early stages and more work needs to be done. The study was carried out by researchers from The Institute of Cancer Research and The Royal Marsden Hospital in London and it was published in the journal Science. This is a valuable study that opens up new areas for cancer treatment, it is often difficult to know which drugs a person may respond to, especially if they have tried several treatments. This work shows that it is possible to replicate a patient’s tumor in the lab, allowing for pre-testing of which therapies they might respond to and which ones they won’t. This research has the potential to help deliver truly personalized treatments and avoid repeated trials for many patients when clinicians offer them a new cancer drug. This could help ensure that effective treatments are administered early, which could slow tumor progression and improve patient prognosis. However, this research is still in its early stages and replicating miniature tumors has not yet been used to guide treatment, so further research is needed to see if this will lead to more cancers being cured and improved survival rates.