Test Code SSTR2 Somatostatin Receptor 2 (SSTR2), Immunostain, Technical Component Only
Reporting Name
Somatost Rc2 (SSTR2), IHC Tech OnlyUseful For
Aids in the identification of neuroendocrine tumors
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
IHTOI | IHC Initial, Tech Only | No | No |
IHTOA | IHC Additional, Tech Only | No | No |
Method Name
Immunohistochemistry (IHC)
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
TECHONLYOrdering Guidance
This test includes only technical performance of the stain (no pathologist interpretation is performed). If diagnostic consultation by a pathologist is required order PATHC / Pathology Consultation.
Shipping Instructions
Attach the green "Attention Pathology" address label (T498) and the pink Immunostain Technical Only label included in the kit to the outside of the transport container.
Specimen Required
Specimen Type: Tissue
Supplies: Immunostain Technical Only Envelope (T693)
Container/Tube: Immunostain Technical Only Envelope
Preferred:
-Formalin-fixed, paraffin-embedded tissue block
OR
-2 Unstained, positively charged glass slides (25- x 75- x 1-mm) per test ordered; sections 4-microns thick
Acceptable: None
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
TECHONLY | Ambient (preferred) | ||
Refrigerated |
Reject Due To
Wet/frozen tissue Cytology smears Nonformalin fixed tissue Nonparaffin embedded tissue Noncharged slides ProbeOn slides Snowcoat slides |
Reject |
Day(s) Performed
Monday through Friday
CPT Code Information
88342-TC, primary
88341-TC, if additional IHC
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SSTR2 | Somatost Rc2 (SSTR2), IHC Tech Only | Order only;no result |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
113598 | Somatost Rc2 (SSTR2) IHC, Tech Only | Bill only; no result |
Secondary ID
113597Clinical Information
Somatostatin receptor 2 (SSTR2) is expressed in the secretory cells of the pancreas and the neurons of the central nervous system. SSTR2 is overexpressed in neuroendocrine tumors and can help predict response to targeted radiopeptide therapy. SSTR2 expression can also play a role in guiding imaging studies and treatment choice.
Interpretation
This test does not include pathologist interpretation, only technical performance of the stain. If interpretation is required, order PATHC / Pathology Consultation for a full diagnostic evaluation or second opinion of the case.
The positive and negative controls are verified as showing appropriate immunoreactivity. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request; call 855-516-8404.
Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.
Cautions
Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary widely among published literature and are antigen dependent. Best practice is for paraffin sections to be cut within 6 weeks.
The charge of glass slides can be affected by environmental factors and subsequently may alter slide staining. Sending unsuitable glass slides can result in inconsistent staining due to poor slide surface chemistry.
Best practices for storage of positively charged slides:
-Minimize time slides are stored after being unpackaged
-Limit exposure to high humidity and heat
-Minimize exposure to plastics
Clinical Reference
1. Kiseljak-Vassiliades K, Xu M, Mills TS, et al. Differential somatostatin receptor (SSTR) 1-5 expression and downstream effectors in histologic subtypes of growth hormone pituitary tumors. Mol Cell Endocrinol. 2015;417:73-83
2. Brunner P, Jorg AC, Glatz K, et al. The prognostic and predictive value of sstr2-immunohistochemistry and sstr2-targeted imaging in neuroendocrine tumors. Eur J Nucl Med Mol Imaging. 2017;44(3):468-475
3. Sizdahkhani S, Feldman MJ, Piazza MG, et al. Somatostatin receptor expression on von Hippel-Lindau-associated hemangioblastomas offers novel therapeutic target. Sci Rep. 2017;7:40822
4. Shen Z, Chen X, Li Q, et al. SSTR2 promoter hypermethylation is associated with the risk and progression of laryngeal squamous cell carcinoma in males. Diagn Pathol. 2016;11:10
5. Magaki S, Hojat SA, Wei B, So A, Yong WH. An introduction to the performance of immunohistochemistry. Methods Mol Biol. 2019;1897:289-298. doi:10.1007/978-1-4939-8935-5
Method Description
Immunohistochemistry on sections of paraffin-embedded tissue.(Unpublished Mayo method)
Report Available
1 to 3 daysSpecimen Retention Time
Until staining is complete.Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.Forms
If not ordering electronically, complete, print, and send an Immunohistochemical (IHC)/In Situ Hybridization (ISH) Stains Request (T763) with the specimen.