An oncologist from Novosibirsk spoke about metastases and cancer diagnostics. In the latest issue of the Oncolikbez rubric, we will tell you about the methods of cancer diagnostics – both the usual ultrasound and CT, and scintigraphy, SPECT / CT and MRI of the mammary glands (do not be alarmed by incomprehensible abbreviations – we will explain what it is).
Medical observer of the NHS Maria Tishchenko spoke with the head of the department of radiation diagnostics of the oncological dispensary Natalia Ushakova. Why is it important to choose a powerful MRI machine, how to avoid errors when doing research in different clinics, is it necessary to do CT only with contrast, and is it true that after one of the examinations, clothes need to be burned? Answers to the most important questions – read in the interview.
– What research is there for diagnosing cancer, clarifying the diagnosis or tracking dynamics?
– Our department of radiation diagnostics includes five divisions – X-ray, computed and magnetic resonance imaging, ultrasound and a radioisotope laboratory in which SPECT / CT is performed (high-tech diagnostic examination of tissues and organs using radioisotopes, which allows you to see an image of an organ, its dimensions, structure, lesion site and assess the functional features. – Approx. ed.).
X-ray is one of the methods of radiation diagnostics, which is based on the examination of the internal organs of a person using X-rays. This method is used to study the organs of the chest, osteoarticular system, gastrointestinal tract.
Mammography is a study of the mammary glands using X-rays, it is used for prophylactic purposes (as screening), as well as diagnostic (to clarify the nature of the formation in the gland, detected by ultrasound or clinical research).
The radioisotope laboratory contains a SPECT / CT (single-photon emission computed tomography in combination with CT) machine – a highly sensitive diagnostic method that allows you to scan the entire body, a limited area or an individual organ.
The main task of radionuclide research in oncology is to assess the prevalence of the tumor process and the effectiveness of treatment. This method is most widely used in the study of bones – osteoscintigraphy. In our department we also deal with scintigraphy of the thyroid gland, parathyroid glands, lymphoscintigraphy, nephroscintigraphy, liver scintigraphy.
Computed tomography and magnetic resonance imaging are one of the best non-invasive diagnostic methods. It allows you to reconstruct very thin sections, visualize changes, the size of which does not exceed even a few millimeters, which makes it possible to detect diseases at the earliest stages.
The computed tomography unit has two tomographs for diagnostic procedures and CT planning before starting radiation therapy. The second newest device was recently installed. It is a state-of-the-art 64-slice device with the highest image quality, with the ability to reduce radiation exposure during scanning.
Computed tomography is a diagnostic method based on a layer-by-layer study of the structure of internal organs and systems. The data are obtained using X-ray equipment, combined with a powerful computer station, which allows for prompt detailed analysis of the image.
Computed tomography is used to examine the organs of the chest (with the help of CT, benign and malignant formations of various localization can be detected – tuberculosis, pneumonia, developmental anomalies, vascular disorders and other diseases), organs of the abdominal cavity and retroperitoneal space, organs of the small pelvis, brain, bones of the skull, paranasal sinuses, spine, joints, blood vessels.
MRI (magnetic resonance imaging) is a modern diagnostic technique that uses a magnetic field and radio waves, rather than ionizing radiation, which is used in X-ray machines and computed tomography. Therefore, MRI is safe and can be done as often as needed.
The most in demand are MRI of the abdominal organs, pelvic organs, spine, joints, and brain. In our arsenal there is a special coil for examining the mammary glands. Employees are now learning this technique.
– What possibilities does this coil provide? How will it help examine the mammary glands?
– MRI of the breast is a more accurate study for finding a tumor, when other methods cannot reliably verify the formation. For example, in the study of “X-ray dense” mammary glands, with a negative ultrasound result, in the early stages, which are almost impossible to detect using other research methods, especially for women with a high risk of developing this disease. Also, MRI of the mammary glands is used to assess the prevalence of the process, to check the status of implants after reconstructive surgeries and to assess the dynamics of the disease after chemotherapy.
– There is a widespread belief that X-ray is not a very reliable examination method compared to others. In what situations is it still sufficient?
– We have a new X-ray machine: the image quality is very high. In practice, we see that some small metastases, which would have been missed on another analog device, are visualized quite clearly on this, therefore, much depends on the quality of the technology.
– What kind of radiation exposure does the patient receive? This is not dangerous?
– On modern devices, the radiation exposure is minimal: they have the latest technologies that allow you to reduce it. For some types of CT examinations, the radiation exposure is even equal to that which can be obtained during a conventional X-ray.
For prevention, fluorography should be done once a year. And when a pathology is detected, there are recommendations for each disease, and it is the attending physicians who prescribe as many procedures and those types of diagnostics that are necessary for a particular patient in order to effectively track the course of treatment.
Now the community of radiologists is concerned that many clinics accept without a doctor’s referral, but not all patients understand what kind of research this is, what the consequences may be. Therefore, at the slightest complaint, patients run to do CT. In some situations, this was not worth doing at all, but in some it was possible to use a different method.
– If we are talking about the search for metastases, then the doctors understand what type of cancer the patient has, and mainly refer to some specific research?
– Yes, as a rule, doctors are guided by the type of cancer and the patient’s complaints, but everything is individual. Each cancer has its own path of metastasis. In each case, it is necessary to consult an oncologist to determine the necessary examination plan (from a simple X-ray examination to MSCT or scintigraphy) for the patient.
– How urgent is the problem of the quality of MRI machines in our city: if their capacity in Tesla is lower (for example, 0.4 Tesla), then patients can be misdiagnosed?
– This is very relevant. We have a machine with a capacity of 1.5 Tesla – for an oncological dispensary, this is the most optimal option for routine work.
– There are difficulties due to the fact that patients do research in different medical institutions, where the results are interpreted in different ways, and then you need to track the dynamics of tumor development?
– Yes, sometimes difficulties arise. Patients often forget to bring a disc if they have undergone examinations at other centers.
Our doctors always look at previous studies, images and make their own descriptions, not relying on the conclusions made before them. Everyone measures education in their own way, there may be errors, so it is imperative to analyze electronic data, images of previous scans.
– What myths do you encounter in your work – what questions do patients often ask?
– There was such a myth, and I think that we managed to debunk it: patients called and said that they needed to do CT with contrast. To the question “Why?” we received the following answer: “Well, how is it: without contrast, nothing is visible, but with contrast, everything is visible.” But it is not so. In general, in each case, the examination plan is determined by the attending physician.
Sometimes patients are also mistaken that there is radiation exposure during MRI studies, but this is not the case.
It happens that patients come to a radioisotope laboratory for research and say: “Doctor, will I need to burn my clothes after I pass your test?”, To which the doctors give an unequivocal negative answer. The isotopes used in our clinic are very short-lived: the radiopharmaceutical is quickly excreted from the body – after 1–2 days it leaves the body completely, so there are no side effects associated with radiation.
Three more important texts about oncology
The Novosibirsk radiologist told how cancer tumors are irradiated and how long the treatment takes.