determine whether neoplastic deposits represent
metastases or new primary lung cancer
Overview
Clinical Indications
Mutations of tumor suppressor genes and/or oncogenes are frequently identified in human cancers. These mutations often appear before detectable morphological changes. Identification of the mutational profile may be a useful indicator to:
- Compare the mutational fingerprint of two or more sites of cancer to determine whether the neoplastic deposits are representative of a recurrence/metastasis of cancer or a new primary (independent) cancer.
- Define the primary site of formation in relationship to multiple sites of metastatic spread.
- Differentiate multicentric carcinoma versus intra-organ spread of one cancer.
- Differentiate local recurrence of cancer versus new primary cancer formation.
- Define the presence or absence of cancer in atypical cytology by comparing the mutational fingerprint with that of known previous cancer.
Specimens derived from solid tumors including colorectal, lung, breast, gynecologic, and liver are appropriate for this analysis.
Methodology
Microdissection to obtain minute representative areas of cellular atypia followed by polymerase chain
reaction (PCR) / Fragment based analysis for loss of heterozygosity (LOH) using a panel of microsatellite markers in proximity to 16 tumor suppressor genes including P16, PTEN, TP53, VHL, DPC4, and OGG1.
Analysis of oncogenes and additional markers of tumor suppressor genes may be added to the panel depending on the type of organ, tissue, or histopathology.
Ordering Instructions
Testing can be initiated only upon receipt of a signed, completed requisition for RespriDx. All available imaging or clinical data, such as cytology or histopathology reports, should be submitted. Clinical data will be included in the integrated report. Contact Client Services at 1-800-495-9885 for details.
Turnaround Time
Less than 18 business days after receipt of specimen or fluid and a signed, completed test requisition.
Specimens
Histopathology slides – Formalin fixed, paraffin embedded (FFPE) tissues:
- Submit eight (8) unstained, recut, 4-5μm tissue sections from paraffin blocks on slides, and one (1) H&E stained slide.
- Submit most representative section(s). Include one section that contains non-neoplastic tissue for use as a control.
- Decalcified, bleached, or Zenker’s or Bouin’s fixed tissues are not acceptable for testing.
Cytology slides:
- Papanicolaou stained smear or ThinPrep® slides are acceptable.
- Other stains may affect the assay. Please notify Client Services (1-800-495-9885) prior to submission. Slides most representative of the pathologic state should be submitted for testing. Specimens should include cells that demonstrate the greatest atypia or malignancy for accurate test interpretation. Interpretation of the molecular results may be limited if too few cells are present in the sample.
Paraffin blocks:
- Paraffin blocks may be submitted. There will be additional process time for the cutting and preparation of sections.
Storage and Shipping Instructions
- Slides or paraffin blocks can be shipped Monday through Friday for next day delivery to Interpace Diagnostics.
- Specimens shipped on Friday should be labeled “For Saturday delivery” on the airbill.
- Specimens should be shipped in the appropriate collection and shipping kit.
- Maintain paraffin blocks and slides at room temperature. In warm weather, ensure that paraffin blocks do not melt by including a cold pack in an insulated shipper.
Limitations
Mutational analysis is not intended for:
- Diagnosis of lymphomas or leukemias.
- Determination of the origin of tumor when the primary cancer is unknown.
Questions?
Sources
- Diagnostic and Prognostic Utility of Molecular Markers in Synchronous Bilateral Breast Carcinoma. Saad RS, Denning KL, Finkelstein SD, Liu Y, Periera TC, Lin, Silverman JF. Modern Pathology. 2008;1-8.
- Patterns of Allelic Loss of Synchronous Adenocarcinomas of the Lung. Dacic S, Ionescu DN, Finkelstein, SD, Yousem SA. American Journal of Surgical Pathology. 2005;29:897-902.
- Molecular Profiling of Primary and Metastatic Neoplasms in the Lung Using Cytologic Material Obtained by Fine-Needle Aspiration: Report of Two Cases. Schoedel KE, Finkelstein SD, Swalsky PA, Ohori NP. Diagnostic Cytopathology. 2004;30(5):342-346.
- Modern Pathology Microdissection-Based Allelotyping Discriminates De Novo Tumor From Intrahepatic Spread in Hepatocellular Carcinoma. Finkelstein S, Marsh W, Demetris AJ, Swalsky PA, Sasatomi E, Bonham A, Subotin M, Dvorchik I. Hepatology. 2003;37:871-9.
- Shen C, Wang X, Tian L, Che G. Microsatellite alteration in multiple primary lung cancer. J Thorac Dis. 2014;6(10):1499–1505.
