While created with anatomic pathology in mind, the DICOM Specimen Module is designed to support specimen identification, collection, sampling and processing attributes for a wide range of laboratory workflows. The Module is designed in a general way so not to limit the nature, scope, scale or complexity of laboratory (diagnostic) workflow that may generate DICOM images.
To provide specificity on the general process, the Module provides extendable lists of Container Types, Container Component Types, Specimen Types, Specimen Collection Types, Specimen Process Types and Staining Types. It is expected that the value sets for these “types” can be specialized to describe a wide range of laboratory procedures.
In typical anatomic pathology practice, and in Laboratory Information Systems, there are conventionally three identified levels of specimen preparation – part, block, and slide. These terms are actually conflations of the concepts of specimen and container. Not all processing can be described by only these three levels.
A part is the uniquely identified tissue or material collected from the patient and delivered to the pathology department for examination. Examples of parts would include a lung resection, colon biopsy at 20 cm, colon biopsy at 30 cm, peripheral blood sample, cervical cells obtained via scraping or brush, etc. A part can be delivered in a wide range of containers, usually labeled with the patients name, medical record number, and a short description of the specimen such as “colon biopsy at 20 cm”. At accession, the lab creates a part identifier and writes it on the container. The container therefore conveys the part’s identifier in the lab.
A block is a uniquely identified container, typically a cassette, containing one or more pieces of tissue dissected from the part (tissue dice). The tissue pieces may be considered, by some laboratories, as separate specimens. However in most labs, all the tissue pieces in a block are considered a single specimen.
A slide is a uniquely identified container, typically a glass microscope slide, containing tissue or other material. Common slide preparations include:
“Tissue sections” created from tissue embedded in blocks. (1 slide typically contains one or more tissue sections coming from one block)
“Touch preps” prepared by placing a slide into contact with unprocessed tissue.
“Liquid preparations” are a thin layer of cells created from a suspension.