Early diagnosis of any tumor largely determines the success of the upcoming treatment. The main objectives of diagnosis include:
establishment of localization, size and extent of the process that allows us to define the stage and prognosis of the disease.
definition of types of tumors (histological, immunochemical, genetic)
Despite its apparent simplicity, the process of diagnosis can be quite complex, multicomponent, and very diverse. There are several main stages of diagnostics
A. It is extremely important collection of history, which is usually preceded by other diagnostic methods. There is a spectrum of symptoms that can be suspected neoplastic process. For example, for leukemia is characterized by pallor and fatigue, and sometimes swelling of the neck and face, fever, with bone pain, etc. For Hodgkin's disease is characterized by weight loss, the appearance of swelling in the neck. For osteosarcoma - lame for retinoblastoma - a glowing pupil, etc.
Two. The next step is to visualize pathology. Medical imaging techniques include the following types:
Ultrasound
X-ray diffraction methods
Radioisotope techniques
Magnetic method
The ultrasonic diagnostic method can provide a considerable amount of information about the process of tumor: - involvement in the process of tumor blood vessels and lymph nodes - definition of the nature of the tumor, its density, size - detection of metastases
X-ray methods can be divided into rengenograficheskie and tomographic.
To determine the prevalence of the process, the size of the tumor and some other parameters using survey images: radiography of the chest in two projections, abdominal radiography, radiography of the limbs, skull, some bones. Sometimes using an intravenous urography (eg, Wilms' tumor).
The most informative method is the X-ray computed tomography (CT, CT). You can use it to evaluate multiple parameters of tumor growth on the localization, size, character growth, presence of metastases. In pediatric oncology CT scan shows the detection of small metastases, and therefore has value in the assessment of patients with germ cell tumors, sarcomas, tumors of the liver tumor, Wilms. Blagodyarya high-resolution, lower dose rates in modern CT apparatus is also used to determine the effectiveness of treatment.
Magnetic resonance imaging (MRI). It is equally effective and informative method of imaging is CT. Unlike the latter, has its advantages and disadvantages. Slaboeffektiven MRI in detecting bone tumors, tumors of the posterior cranial fossa, skull base. However, soft tissue tumors are visualized very contrasting and sometimes better than with CT. MRI and CT scans as often used with contrast agents that increase the sensitivity of the method.
Radioisotope methods of diagnosis in children are mainly used to detect bone tumors, lymphoproliferative tumors, neuroblastoma, as well as for some functional tests.
Three. The next important stage of diagnosis - verification of the disease. From its accuracy will depend on the choice of treatment, prognosis and treatment efficacy. The following verification methods:
Microscopy. There are light-optical, electronic and laser microscopy. Microscopy requires pre-training study material, sometimes quite long. The most common light microscopy, which allows to determine the cellular and tissue structure of tumors, tumor grade, growth pattern, presence of metastases, etc. Electronic microscopy and laser required only for certain types of tumors for differential diagnosis and more accurate verification.
Immunofluorescence analysis. The method is based on the detection of luminous antigen-antibody complex using specific monoclonal antibodies with glowing marks to the antigens of the membranes of tumor cells. Allows you to diagnose different subtypes of a disease on the expression of a particular trait that can be detected by this method. Widely used in the diagnosis of leukemia.
Immunosorbent assay. Immunofluorescence is similar, but instead of glowing marks used enzyme label.
Analysis of DNA:
Cytogenetic analysis. The first genetic marker of tumor was described in 1960 and was called "Philadelphia chromosome", because researchers working in Philadelphia. Today, we describe the set of specific and nonspecific genetic tumor markers characteristic of a particular pathology. As a result of this method of diagnosis is possible to identify predisposition to tumor development, as well as early detection of disease.
Southern blot analysis. Estimates the number of gene copies in the cell. Rarely used because of the large price of the study.
Polymerase chain reaction (PCR, PCR). A very common method for estimating the genetic information in DNA is a very high sensitivity.
On this list of methods is not finished. Using other methods, and indeed most of these, determined by the specific tasks of diagnosis and characteristics of the disease.
