Home > News > Content
FISH Detection Of Adult Chronic Myeloid Leukemia (2018 Edition)
- Jan 04, 2019 -

In order to further improve the standardization level of cancer diagnosis and treatment , to ensure the quality and safety of medical treatment, the National Health Commission has revised the diagnostic and treatment criteria for 18 kinds of cancer, such as primary lung cancer, and formed the relevant criteria for cancer diagnosis and treatment (2018 edition).

Healthcare Biotechnology will analyze the relevant contents of FISH test in these cancer diagnostic and therapeutic criteria. Today, we first understand the criteria for diagnosis and treatment of adult chronic myelogenous leukemia (2018 edition).

Chronic myelogenous leukemia (CML), often referred to as chronic myelogenous leukemia, is a malignant tumor formed by clonal proliferation of bone marrow hematopoietic stem cells. It is characterized by abnormal increase of peripheral leukocytes and the increase of neutrophils, late granulocytes and mature granulocytes, eosinophils and basophils. More than 95% of patients have Ph chromosomes, and all CML have BCR and ABL1 gene rearrangements.

Genetic evidence is a necessary condition for the diagnosis of CML. Cytogenetic examination showed that the presence of Ph chromosome or BCR, ABL1 gene rearrangement (bcr/abl1 fusion gene) could confirm the diagnosis of CML. Routine cytogenetic examination is the most commonly used means of detection. 95% of patients can find Ph chromosome by routine chromosome analysis and make a definite diagnosis. Some patients can detect abnormal karyotypes other than Ph chromosome. Fluorescence in situ hybridization (FISH) is a sensitive and accurate technique for detecting BCR and ABL1 gene rearrangement. Some patients with normal karyotype were confirmed by FISH to have a definite diagnosis of BCR/ABL1 rearrangement.

Variant Ph chromosomes: Complex translocations (cumulative 3 or more chromosomes) are often formed in 5% of patients. Chromosomes other than Y chromosomes can be involved. In variant Ph chromosomes, 22q- exists, but the missing part translocates to chromosomes other than chromosome 9, or forms complex genetic material exchanges involving chromosomes 9, 22 and other chromosomes. High-resolution techniques analysis showed that the fusion of 9q34 and 22q11 was fundamental to the formation of Ph chromosomes, both classical and complex.

Occult Ph chromosome: 9q34 and 22q11 exchange translocations, 9q34 to 22q11 form 22q-, 9q+, 22q-under optical microscope is the identification marker of Ph chromosome, in a few cases, 22q-after translocation is longer than classical type under optical microscope and can not be recognized, that is, the so-called occult Ph chromosome. At this time, BCR-ABL rearrangement is confirmed by banding technology and molecular methods.

About 70% of patients in chronic phase are classical Ph chromosomes, 20% of patients have other chromosomal abnormalities, including Y, +8, +22q, +Ph, etc., and the proportion of normal people over 60 years old is 10%. 

In some rare BCR-ABL1 fusion types (such as b2a3), both conventional karyotype analysis and RT-PCR showed negative results. FISH results showed that ABL gene was atypically inserted into BCR gene on chromosome 22. BCR-ABL fusion was positive. It was diagnosed as CML and received imatinib 400 mg/day. After 6 months of treatment, FISH was used to detect and complete cytogenetic response. If the patient only carries out karyotype analysis and RT-PCR detection, without FISH detection, CML will not be diagnosed and timely imatinib treatment will be delayed seriously.

image

Therefore, in order to ensure that CML patients do not miss diagnosis and accurately monitor the therapeutic effect, FISH detection is needed. The Fast FISH Probe  of Healthcare Biotechnology adopts the principle of non-repetitive sequence design. It has the following characteristics: first, fast: short hybridization time, free choice of 2-16 hours hybridization according to clinical needs, Fast FISH Probe can be completed quickly in case of need of re-examination, greatly reducing the waiting time of clinical departments and patients. Secondly, it has high specificity, accurate positioning of hybridization signals and less non-specific hybridization signals. Thirdly, the sensitivity is high, and the detection advantage of minimal residual lesions in clinic is better than that of traditional probes.

image

                                                          BCR/ABL gene negative fusion

  BCR/ABL gene positive fusion

Wuhan Healthcare Biotechnology Co., Ltd. is located in Wuhan Optics Valley Biolake, the national bio-industrial base. The company is a high-tech enterprise integrating R&D, production, sales and testing services with the strategic direction of precise medical diagnosis products for major diseases such as tumors, cardiovascular and cerebrovascular diseases.

Since its inception, the company has been committed to providing more efficient diagnostic products, insisting on independent research and development, and has established research and development teams in clinical medicine, molecular biology, microfluidic control, mechanical automation and other disciplines. The company has won more than 10 invention patents at home and abroad, and FastProbe ®Fast FISH  probe preparation technology with full independent intellectual property rights is in the leading international level. The incubation time of new generation probes based on patented technology is only 2 hours, and the detection time of fluorescence in situ hybridization is shortened from 3 days to several hours, with higher sensitivity, specificity and signal-to-noise ratio. The company independently developed and internationally pioneered automatic fluorescence in situ hybridization platform, automatic fluorescence scanning system and computer artificial intelligence result interpretation system for microfluidic chips, which realized the rapid, automatic, high throughput and intelligent FISH detection of bone marrow, peripheral blood and exfoliated cells. This subversive technology greatly promoted the clinical application of fluorescence in situ hybridization technology. Based on the advantages of technology and products, the company has built a complete marketing system at home and abroad. The products have entered more than 20 countries and regions, won a good market reputation and wide customer recognition, and become a leading brand of fast fluorescence in situ hybridization probe in the world.

The company has always adhered to the purpose of "fast, accurate, more than this". It has been working tirelessly to advance and contribute to the development of global precision medical cause.