Frozen Specimen Samples VS. FFPE
Frozen Samples or FFPE?
Both the frozen specimen and FFPE preservation method hold important roles in the analyzing of human tissue samples. The applications for use are very distinct. Each presents its own unique set of benefits and limitations. Many research studies discuss different clinical applications and the efficacy of each method in various circumstances. In some instances, a geneticist benefits from using FFPE compared to frozen human tissue samples and vice versa.
Researchers cite that in areas of molecular discovery, frozen samples might be optimal. However, they are not always available. In one clinical study, the use of FFPE tissue samples is shown to be superior to that of frozen samples. When they combined FFPE with other DNA extraction methods, it demonstrated greater feasibility for determining genetic variables and other important biological information. Additionally, geneticists also find when trying to identify genetic variations that FFPE is ideas as a supplement to frozen samples for the detection of SNV’s.
About Frozen Specimens
The frozen section procedure is the avenue in which a sample can be prepared for rapid microscopic analysis of a specimen. The technical name for it is cryosection because the instrumentation used in this procedure is called the cryostat. (A microtome in the freezer). This procedure occurs most often in the course of oncology-based surgeries.
Frozen section is important in the diagnosis of lesions or tumors and serves to determine if a sample is presenting with malignant or benign components and if the tumor has metastasized. The surgeon can then make a decision f there is an active reason to continue the surgery process.
What Are the Advantages and Disadvantages of the Frozen Section Procedure?
Advantages:
On rare occasions, frozen section methodology can be used to detect antigens masked by formalin in traditional histological techniques such as in the case of lipids.
The preferred method for RNA samples and other proteins.
Frozen section shortens the amount of time to initial diagnosis as opposed to traditional tissue biopsy preparation. Results can be communicated quickly.
The accuracy is considered to be high when clinical relevance is demonstrated.
Disadvantages:
The frozen section method is known to be demanding by even the most seasoned histologists. It can become increasingly stressful when multiple specimens arrive simultaneously from surgeons.
There are some limitations that the ordering doctor should consider in regards to frozen section sampling. The pathologist is interpreting tissue from a limited sample size therefore in some cases, a frozen sample diagnosis cannot be made.
Poor preparation can have disastrous results. Pathologists have to work within a high-pressure circumstance and perform detailed work with limited sample sizes. The diagnosis then determines the continuation of surgery for a patient. Clinical studies cite that extreme care must be taken during preparation.
Ice crystal formations negatively affect human tissue structures.
About FFPE (Formalin Fixed Paraffin Embedded)
It is a common method for preserving and storing tissue samples. The formalin functions to paralyze cell metabolism while the paraffin seals the tissue and reduces the rain of oxidation.
What Are the Advantages and Disadvantages of Using FFPE Tissue?
Advantages:
Because FFPE samples can be stored at ambient temperatures for decades, they are very important to disease research and drug discovery.
FFPE samples are embedded in wax which means they can be cut easily into thin slices and mounted on a microscope for examination purposes. FFPE samples are the most common archived tissue material.
FFPE is cost-effective because they don’t need specialized materials or equipment for storage.
FFPE is also favorable because larger collection quantities can be stored.
In FFPE, the paraffin and wax ensure that cell structures and proteins are well-preserved.
The process is considered to lean toward rapid analysis.
Disadvantages:
The use of formalin which is toxic, carcinogenic, and a poor preserver of nucleic acids.
The fixation of wax and paraffin can be time-consuming.
There isn’t any standardized method of preparing FFPE samples. This means there isn’t a guarantee all samples will be provided in a uniform way.
The proteins even though preserved, are denatured therefore they are no longer biologically active. This means the human tissue samples preserved in this method can only be used for certain types of studies.
FFPE cannot be used in molecular analysis as the results obtained are not on par when compared to results from frozen tissue samples.
Conclusion
Geneticists and other related medical professionals agree that human tissue preservation methods are subjective and dependent upon the experiment or application. Studies reveal that FFPE has significant relevance toward research and morphology features, whereas the frozen section method shows efficacy in surgical applications. Lastly, researchers find both FFPE and frozen section human tissue samples can be used in conjunction to help reproduce genetic components and sequencing results. The technologies to help further these findings in modern clinical applications.
