Standardized Management and Ethical Requirements of Human Tissue Paraffin Blocks in Biobanks

Sources and Informed Consent of Human Tissue Wax Blocks in Biobanks

As one of the important preservation formats in biobanks, the collection and retention of human tissue wax blocks must follow the principle of informed consent. In clinical diagnosis and treatment or research projects, an informed consent form approved by the ethics committee should be used to clearly inform subjects of the purpose of the samples, retention period, privacy protection measures, and the means by which subjects may withdraw consent. Biobanks should establish comprehensive management of the scope of authorization to avoid using samples for research beyond the authorized scope. For historical samples, compliance should also be assessed according to current regulations and institutional policies.

Labeling, Records, and Information Management for Wax Block Preservation

An important task in standardized management is to ensure that each human tissue wax block has a unique identifier and is linked to clinical information, pathological diagnosis, and sample processing records. Paper records and electronic systems may be managed in parallel, but should be checked regularly to reduce blurred labels, duplicate numbers, or missing information. Common practices include using labels resistant to low temperatures and organic solvents, and printing two-dimensional barcodes on the side of the wax block or on the embedding cassette. Information systems can record storage location, time of check-in and check-out, and purpose, facilitating traceability and statistical analysis.

Establish a unique identifier and link it to the pathology number and clinical information

Use solvent-resistant labels and regularly check label integrity

Check-in and check-out operations should be promptly entered into the information system

Storage Environment and Quality Review Requirements

Paraffin-embedded tissue blocks have relatively moderate environmental requirements, but high temperature, high humidity, and direct sunlight should still be avoided. It is generally recommended that the storage temperature not exceed 25 degrees Celsius, with relative humidity controlled within a reasonable range. A sampling inspection plan can be developed for inventory samples to observe whether the wax blocks are cracked, deformed, moldy, or have detached labels. If abnormalities are found, an timely assessment should be made as to whether they affect subsequent testing, and the handling process should be recorded. Quality review results should be included in the biobank's annual report to provide a basis for continuous improvement.

Ethical Compliance and Boundaries of Sample Use

The use of human tissue wax blocks involves ethical and legal issues. Before research use, the corresponding ethics review approval should be obtained, and activities should be carried out strictly within the approved scope. When genetic testing, data sharing, or cross-institutional transfer is involved, ethical reassessment should be conducted, and informed consent should be re-obtained when necessary. Sample destruction must also be carried out according to institutional policies and procedures, with records retained. Compliance management not only protects the rights and interests of subjects, but also enhances the sustainable operation capacity of biobanks, providing a reliable resource foundation for subsequent research.