Discovery of a Nonspecific Precancer Screening Indicator named “Dicentric+Translocation” of the Chromosomal Aberrations

Background: To search the major carcinogenic factor or explore a non - specific early- stage and rapid screening indicators of cancer. Methods: Select 49 tumor patients and 60 healthy persons, Chromosome aberration and lymphocyte micronucleus were analyzed before radiation therapy of tumor patients. Results: the “Dicentric + Translocation” of Chromosome 36(73.47%).The frequency of chromosome aberration and lymphocyte micronucleus were higher, especially the “Dicentric+Translocation “of chromosome aberrations (P <0.01), the frequency of double centromere chromosomes and translocation increased; the chromosome conglutination and dissolution appeared. Conclusion: Could it be used as an early screening indicator for cancer; does it suggest that ionizing radiation is a major carcinogen? It is worthy of further study.


Background
Identifying the causes of human cancer is the first step in cancer prevention. The identification of a cancer hazard may have broad and profound implications. As a disease with a truly global reach, cancer has touched most people in a personal way. Importantly, this new appreciation of cancer's complexity is redirecting attention to cancer prevention and early detection -research areas.
Cancer is not one disease, but many diseases. Cancer is a disease in which normal cells divide out of control and can invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymphatic system. Cancer can be caused by many factors, such as exposure to carcinogens, genetic mutations, certain behaviors, age, and so on.
There are many ways to screen for cancer. Main types: physical examination and history: Examining the body for general signs of health, including signs of illness, such as a lump or other unusual object. The patient's living habits, past illnesses and treatment measures. Laboratory testing: Testing of human blood, tissue, urine or other substances. Imaging screening: Imaging of the internal areas of the body. Genetic test: Laboratory test that analyzes cells or tissues to look for genetic or chromosomal changes. These screening methods are used to find out whether a person is at risk for a particular disease or condition [1].   Slides were produced. It was stained by giemsa staining, air-dried and coded. It was used to analyze the lymphocyte chromosome aberration [2,3].

Reagents and Instruments
Peripheral blood 2ml was collected from each cancer patient and divided into 0.5 mL portions before radiation therapy and healthy people were distinguished; 0.5 mL of the blood was added to 4 mL portion of the culture media (80% RPMI-1640 and 20% FBS

Statistical Methods
The statistical analysis software SPSS version 10.0 was used for the analysis of variance and t test for each corresponding groups.
"Dicentric+Translocation" Chromosome Analysis All slides were used to analyze the lymphocyte chromosome aberration and micronucleus assay by the Olympus microscope; about 4360 metaphases were analyzed before RT and 6700 metaphases of healthy people were analyzed.  "Dicentric+Translocation" is a specific chromosomal aberration caused by ionizing radiation, the background value is around 0.06%.

Detection and analysis of micronucleus in peripheral blood lymphocytes (Table 2)
Table2: Lymphocyte micronucleus detection analysis.  People who detect and treat cancer early improve survival or prolong survival compared with those who don't find the disease until symptoms appear. For many cancers, on the other hand, there are no good screening tests for early detection. There have been effective early screening tests, many of which have not been shown to be effective in reducing cancer mortality [9][10][11][12][13][14].

Subject
Many studies have found that screening has drawbacks as well as benefits. There is a risk of overdiagnosis and overtreatment-that is, of diagnosing and treating cancers that are not life threatening or causing symptoms. However, overdiagnosis and overtreatment unnecessarily expose patients to the potential physical harm of unnecessary and often invasive diagnostic tests and treatments, as well as the psychological stress associated with cancer diagnosis.
The current important work is how to improve the accuracy of cancer screening tests and expand the accuracy of cancer screening methods. There have been some success stories in screening and early detection. In the United States, for example, the death rate from cervical cancer has dropped significantly after annual pap smears, and colorectal and breast cancer screening has also been shown to reduce the death rate from these cancers.
Screening for cervical cancer and colorectal (colon) cancer can prevent cancer by finding early lesions so they can be treated or removed before they become cancerous. Screening for cervical, colorectal, breast, and lung cancers helps find these diseases at an early stage, when treatment works best.

Conclusion
The Dicentric and Translocation are equivalent in chromosomal aberrations caused by ionizing radiation, because the chance of forming a dicentric or translocation is the same when the DNA double strand is broken by a ray.
Could it be used as an early screening indicator for cancer; does it suggest that ionizing radiation is a major carcinogen? It is worthy of further study.

Declarations
Ethics approval and consent to participate.
The research was approved by the Bioethics Committee at the Gansu provincial center for disease control and prevention.
Informed consent was obtained from all individual participants included in the study.