Oncology (prostate), promoter methylation profiling by real-time PCR of 3 genes (GSTP1, APC, RASSF1), utilizing formalin-fixed paraffin-embedded tissue, algorithm reported as a likelihood of prostate cancer detection on repeat biopsy
CPT4 code
Name of the Procedure:
Prostate Cancer Promoter Methylation Profiling by Real-time PCR
Common name: Real-time PCR prostate cancer detection
Technical terms: DNA methylation profiling, GSTP1, APC, RASSF1, formalin-fixed paraffin-embedded (FFPE) tissue
Summary
This procedure tests for prostate cancer by analyzing the methylation status of three specific genes (GSTP1, APC, RASSF1) using real-time PCR. A tissue sample preserved in paraffin is used to determine the likelihood of detecting prostate cancer in any future biopsies.
Purpose
Medical Condition: Prostate cancer
Goals: To evaluate the risk of prostate cancer by detecting aberrant methylation in DNA from prostate tissue, aiding in the decision for repeat biopsies.
Indications
Symptoms such as elevated PSA levels, abnormal digital rectal exam findings, or previous negative biopsies with persistent suspicion of cancer may warrant this procedure. It is suitable for patients with a heightened risk or uncertain diagnosis of prostate cancer.
Preparation
Patients may not need special preparation for this specific test since it uses previously collected tissue samples. However, they should follow general biopsy preparation guidelines, which typically include fasting and medication adjustments as directed by their physician.
Procedure Description
- Sample Collection: Tissue is obtained from an earlier prostate biopsy, preserved in formalin, and embedded in paraffin.
- DNA Extraction: DNA is extracted from the formalin-fixed paraffin-embedded (FFPE) tissue.
- PCR Amplification: Methylation status of the GSTP1, APC, and RASSF1 genes is assessed using real-time PCR.
- Data Analysis: Results are analyzed through an algorithm that reports the likelihood of prostate cancer detection in future biopsies.
No anesthesia or sedation is needed as the procedure is laboratory-based using previously collected tissue samples.
Duration
The laboratory analysis typically takes a few hours to a couple of days, depending on the lab's processing times.
Setting
Performed in a specialized laboratory equipped for molecular diagnostics.
Personnel
Molecular biologists, laboratory technicians, and pathologists work collaboratively to perform and interpret the test.
Risks and Complications
Since the procedure uses pre-existing tissue samples, there are minimal risks to the patient. Handling and processing errors are rare but possible.
Benefits
This method provides a non-invasive way to predict the likelihood of prostate cancer detection on repeat biopsy, potentially reducing the need for unnecessary biopsies and aiding in early cancer detection. Results are usually available within a few days.
Recovery
There is no physical recovery needed from the test itself since it does not require new tissue sampling.
Alternatives
Other diagnostic options include:
- Repeated traditional biopsy
- MRI or ultrasound-guided biopsies
- PSA testing and monitoring
Each alternative varies in invasiveness, accuracy, and patient suitability.
Patient Experience
Patients can expect minimal direct involvement beyond the initial biopsy. There are no additional physical discomforts associated with this lab-based test. The results aid in understanding the potential need for further biopsies, reducing uncertainty and anxiety.