Prostate cancer is the 2 nd most commonly diagnosed cancer amongst Australian men. Whilst Prostate cancer is the 2 nd most commonly diagnosed cancer amongst Australian men. Whilst localised prostate cancer can be curatively treated with radiation or surgical resection, 10-20% of men present with metastatic disease. Individual patient responses to pharmacotherapy vary. We present a pipeline of deriving patient-derived organoids as a tool for predicting patient-centric responses to therapy.

At the time of robotic assisted laparoscopic prostatectomy at the Princess Alexandra Hospital, patient tumour tissue, demographic data were collected. Utilising an organoid medium-Matrigel™ suspension, 3D in vitro cultures of patient-derived organoids (PDO) were developed. PDO growth and viability were inspected using time-lapse and fluorescence microscopy. PCa PDOs were treated with combinations of standard-of-care chemotherapies over a 6-day period; with endpoint viability measured to indicate response. Standard histology and immunohistochemistry were conducted on original patient tissue and PDOs to validate the prostatic origin.

To date, our tissue biobank contains, 23 malignant prostate tumours, 8 samples of benign prostate tissue and one benign lymph node. Fourteen patients had definitive histology demonstrating intermediate favourable disease (Gleason 3+4=7). The remainder of patients had intermediate unfavourable disease (Gleason 4+4=8). The vast majority of patients had acinar pattern adenocarcinoma, whereas two patients had mixed ductal-acinar adenocarcinoma and intraductal adenocarcinoma. In our cohort we were able to culture PDOs and conduct personalised drug screens, however the success of organoid generation was low.

Our small cohort demonstrates feasibility in generating PDOs for drug screens, however further optimisation of the organoid process is required.