From the surgical specimen to the tissue bank

Consent form: A prerequisite for obtaining research samples is a valid consent form [LINK]. Tissue assay for iBioTUM is performed by default either in the frozen section laboratory of the Institute of General Pathology and Pathological Anatomy or in the premises of the surgical wing of the Surgical Clinic of the Klinikum rechts der Isar. Special SOPs, so-called Standard Operating Procedures, apply here. These SOPs specify the exact procedure for sample preservation.

No interference with patient care: Tissue preservation is performed exclusively by medical staff of the Institute of General Pathology and Pathological Anatomy. This ensures that in no case will the diagnostic evaluation of the surgical specimen required as part of patient care be compromised. Tissue asservation is performed immediately following the diagnostic evaluation. This keeps the time between receipt of the surgical specimen and shock freezing of the tissue in liquid nitrogen as short as possible.

Short ischemia times: This so-called ischemia time - the time during which the surgically removed tissue remains without blood and oxygen supply - is usually less than 30 minutes. As far as possible, both diseased tissue (e.g., tumor tissue) and healthy tissue are obtained during each tissue assay. After transferring the samples into sample tubes marked with pseudonyms, shock freezing in nitrogen is performed. For this purpose, the pseudonymized sample tubes are transferred into nitrogen tanks intended exclusively for the tissue bank.

Documentation: The documentation of the entire preservation process takes place immediately afterwards and is performed within the framework of a standardized protocol. Sample-oriented data (e.g., type and number of samples) as well as quality-oriented data (e.g., cold and warm ischemia times) are documented. The samples and associated sample data are always pseudonymized and stored separately from each other, so that appropriate data protection requirements are met.

From tissue bank to high quality research sample

Conditions for the use of research samples: Prerequisite for the use of research samples is the approval of a corresponding request by the Use and Access Committee [LINK]. Upon approval, requested tissue samples will be identified via iBioTUM software. After identification of suitable samples with corresponding desired characteristics, these are removed from the nitrogen tanks.

Sample Preparation - Fine Tissue Examination: This is followed by the preparation of a histological slice preparation of the sample as standard. This sectional preparation, usually stained with hematoxylin and eosin, is then evaluated microscopically (fine tissue) by a pathologist with regard to the type of tissue (diagnosis, % tumor cell content if applicable) and quality of the tissue. The results of the microscopic examination are made available to the researchers. Depending on the wishes of the researchers, either sectional preparations will be made or tissue samples will be aliquoted. Care is taken to ensure that the cold chain is not interrupted between the time the samples are removed from the nitrogen tank and the time the desired samples are handed over to the users.

Optional examinations: In addition, tissue microarrays (TMAs) can be prepared or immunohistochemical examinations can be performed upon request.

Fabric Transfer: The transfer of the fabric is usually governed by a Material Transfer Agreement.