Synchronous peritoneal metastasis in advanced gastric or colon carcinoma is still a devastating diagnosis for the affected patients despite modern therapy methods. This is because not only is the quality of life significantly reduced due to, among other things, passenger disturbances and ileus, but life expectancy is also drastically reduced. Although overall survival can be increased by modern systemic chemotherapy, cure is not possible.
As part of a multimodal therapy, a treatment combination consisting of complete surgical resection and perfusion by hyperthermic intraperitoneal chemotherapy (HIPEC) has become established in cases of low-grade PC. It has been shown that a significant increase in overall survival can be achieved with this treatment modality. However, PC recurrence rates of up to 80% are still very high. In addition, despite worldwide use for over 30 years, this treatment method lacks standards as well as patient-specific individualizability. Thus, for PC in colon cancer alone, more than 60 different HIPEC regimens are in use internationally, which so far mainly rely on observational studies or prospective single-arm trials.
Thus, PC offers a clinical setting for preclinical drug testing, e.g. using organoid models, to enable optimal treatment tailored to each individual patient in the future. The present exploratory pilot study aims to establish organoid cultures from tumor material for preclinical testing of HIPEC regimens in the form of mono- and combination therapies, thus investigating the predictive value of the organoid model with respect to the efficacy of the HIPEC procedure. In parallel, extensive molecular genetic studies will be performed on the established organoid cultures to identify resistance to systemic neoadjuvant therapy.
