Molecular Pathology

The molecular changes in rheumatologic malignancies and solid tumours have been making unprecedented strides in oncology and therefore has become pertinent to incorporate molecular data in the pathology reports.

The department of lab medicine at the Basvatarakam Cancer Hospital and Research Institute therefore takes pride in stating that it is one of the few canters in India where the pathologists work with the molecular biologists and sign out reports of molecular pathology in a background of appropriate clinical morphologic correlation and technological, expertise to justify the oncologists & patient queries on targeted therapy and treatment decision.

Molecular cytogenetic services

Molecular Cytogenetics is now an integral diagnostic and prognostic tool in oncology, and aims to provide accurate valuable diagnostic and prognostic information for targeted therapy.

The molecular cytogenetics laboratory with the state of the art infrastructure and trained staff at BIACH&RI offers services for conventional cytogenetics test in leukemias and molecular diagnostics (Hematological malignancies & solid tumors to rapidly and accurately determine the acquired genetic abnormality for medical oncologists at BIACH & RI and beyond.

Services Offered :

Conventional cytogenetics

Cytogenetics is the study of rod like chromosomes in the metaphase stage of cell division

Bone marrow cytogenetics detects acquired chromosome anomalies in the bone marrow or peripheral blood cells where sufficient cancerous or pre-cancerous cells (blast cells) are detected. If the blast count is low in the blood, no cytogenetic results may be possible.

Specimen – 1/2 - 2 ml of early bone marrow aspirate/2-3 ml peripheral blood in sodium heparinized tube/vacutainer. Please supply clinical indication

It includes:

• Cell cultures

• G- banding - Quality and number of cells may be limited if specimen is not adequate

• Banding level: variable, depending on type of neoplasia

• Analysis of 15-20 GTG banded metaphases

• NUMBER OF G-BANDED KARYOTYPES: A minimum of two karyotypes.

• Turn around time - Results reported in 21 days

FISH ANALYSIS OF INTERPHASE CELLS

Fluorescence in situ hybridization (FISH) detects specific gene or chromosome abnormality in non dividing cells and uses a fluorophore labeled probe to identify the abnormality rapidly and accurately in haematological malignancies /solid tumors. The probe DNA can be observed on its target by using a fluorescent microscope with filters specific for the fluorochrome label and the counterstain. Special filters have been developed to allow simultaneous visualization of several fluorochromes. Digital cameras designed to detect low light level emissions and computer imaging are used to increase the sensitivity of probe detection. FISH - interphase cell analysis is used as an adjunct to Cytogenetics or as FISH only.

FISH testing

Extends routine cytogenetic banding methods by resolving ambiguous diagnosis

  • provides a new tool to diagnose submicroscopic abnormalities.

  • Also useful for identification of abnormalities in specimens with a low mitotic index

  • In cases of cytogenetic culture failures

  • Monitoring response to treatment.

FISH FOR GENE AMPLIFICATION:

Gene amplification is a characteristic of cancer cells that allows increased production of specific proteins used for acquisition and maintenance of the malignant phenotype. Amplification of certain oncogenes has an important role in the progression of many tumors. Detection of such amplifications may be of diagnostic and prognostic importance.

The HER-2/neu or erbB-2 oncogene codes for a 185 Kd transmembrane oncoprotein (p185). Approximately 25-30% of breast and ovarian carcinomas have amplification of this gene. Studies have demonstrated that HER-2/neu is amplified and/or overexpressed in 10-30% of invasive breast cancers and in 40-60% of intraductal breast carcinomas.

Amplification and overexpression of this gene were found to be associated with rapid proliferation, low estrogen receptor content, and high grade of ductal carcinomas, which suggests that this oncogene plays an important role in the progression of breast cancer. Further this was shown to be an indicator of poor prognosis in node-positive breast cancer. In node negative breast cancer patients, the subgroup for which accurate prognostic factors could make a significant contribution to treatment decisions.

List of probes here:

Specimens that can be used for FISH include peripheral blood cells, bone marrow cells, and paraffin-embedded tissue sections.

Markers for which FISH services are being offered

FISH probes

Turn around time – Results reported in

PML-RARA-3 days

All other markers 5 days

Solid tumors – 1 week

FISH – positive for MLLgene rearrangement