Orthopedia Homeobox Protein (OTP) Immunostain, Technical Component Only
Use
This test is useful for distinguishing lung carcinoid tumors from metastatic neuroendocrine tumors. The orthopedia homeobox protein (OTP) is a nuclear transcription factor that may serve as a novel prognostic factor associated with pulmonary carcinoid tumors. Negative or weak expression of OTP is associated with poor prognosis. Nuclear staining for OTP has been reported to have high sensitivity and specificity for diagnosing lung carcinoid tumors, while cytoplasmic granular staining does not reflect OTP expression and should not be regarded as positive.
Special Instructions
Not provided.
Limitations
Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary among published literature and are antigen-dependent, with best practice being sections cut within 6 weeks. The charge of glass slides can be affected by environmental factors, potentially altering slide staining. Improper specimen collection and handling conditions, such as sending unsuitable glass slides, may result in inconsistent staining due to poor slide surface chemistry.
New York Approved
Methodology
Immunoassay (IHC)
Biomarkers
Orthopedia Homeobox Protein (OTP)
Protein
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (FFPE)
Volume
Not provided
Minimum Volume
Not provided
Container
Immunostain Technical Only Envelope
Collection Instructions
Please provide formalin-fixed, paraffin-embedded tissue block or 2 unstained, positively charged glass slides per test ordered. Each slide should be 25 x 75 x 1-mm, and sections should be 4-microns thick.
Causes for Rejection
Wet/frozen tissue, cytology smears, nonformalin fixed tissue, nonparaffin embedded tissue, noncharged slides, ProbeOn slides, Snowcoat slides
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Ambient preferred |