Cancer is the scourge of the 21st century, the further progress moves, the more cases of cancer. One of the new methods for detecting cancerous tumors is tumor markers. What is it and can such an analysis be trusted?
What are tumor markers
The word marker comes from the English verb mark, which translates as "mark, label something." The tumor marker is the general name for a blood or urine test for the presence of traces, that is, "marks" that leave cancerous tumors in the body during nucleation, formation and growth.
This is followed by specific proteins or enzymes and their degradation products. Such proteins are produced either by the cancerous tumor itself or by the immune system in response to oncological processes in the body.
Different proteins may form depending on the location of the tumor. Accordingly, this means that tumor markers show where the cancer tumor may be without x-rays. That is why the analysis is used as a diagnostic method along with visual ones such as ultrasound and X-ray.
Varieties of tumor markers and what show
According to the standard, there are more than 200 varieties of tumor markers. The most popular of them are as follows:
- PSA (prostate gland);
- UBC (bladder);
- SA125 (ovaries);
- SA 15–3 (mammary gland);
- SA 19–9 (stomach, intestines, pancreas);
- SA 242 (intestines and pancreas);
- HCG (ovaries, testicles, uterus);
- AFP (cancer of the liver, gall bladder, ovaries, etc.);
- B-2-MG (cancer of the blood and lymph nodes);
- CEA (cancer-embryonic antigen).
The localization of the cancerous tumor indicated by the specific tumor marker indicates in brackets. As you can see, some indicate a specific localization, while others have a variability of diagnosis. Therefore, a combination of markers is often used. For example, in cases of suspected pancreatic cancer, SA 242 and SA 19–9 are prescribed immediately, and for ovarian cancer, AFP, SA125, and hCG. But in any case, with a deviation from the norm, complex diagnostics will be required.
When do tumor markers apply?
Assign them in the following cases:
- if a tumor is suspected, which is not visible during a visual examination;
- to control relapse;
- at risk of malignancy;
- with suspected metastases;
- for preventive purposes, with hereditary and other risks;
- as part of a comprehensive diagnosis;
- monitoring the success of treatment, with a positive outcome, the concentration will begin to decrease.
It is important to understand that a single analysis for thyroid tumor markers, even a cross, is not enough to exclude or, conversely, confirm the presence of a tumor.
Thyroid cancer
This type of cancer is quite rare, mainly in women and the elderly. The thyroid gland is an organ that produces many vital hormones. Lack or excess of which affects growth, mental development, metabolism and overall well-being. The organ is located on the front of the neck and looks like a butterfly: two lobes are connected by a thin isthmus. Due to its proximity to the surface, it is often found at an early stage upon palpation by the patient himself, for example, when washing.
Thyroid cancer has 4 varieties:
- Papillary is about 75% of all malignant tumors in the thyroid gland. Prone to invasive invasions of neighboring organs and lymph nodes.
- Follicular - the second, in particular, type of thyroid cancer. The main reason is iodine deficiency. In this type of cancer, the tumor usually does not leave the thyroid gland.
- Medullary. It is very dangerous, the tumor with it practically does not accumulate radioactive iodine, which makes treatment with it ineffective.
- Anaplastic. This species is characterized by rapid growth and brightly flowing symptoms: hoarseness, coughing up blood, wheezing when breathing, weight loss and difficulty breathing. It is found least of all, but the most dangerous.
Signs of thyroid cancer
The following symptoms are considered signs of a tumor:
- a hoarse voice;
- sharp fluctuation in weight;
- feeling of depression and loss of physical strength;
- pain when swallowing;
- unexplained fever;
- enlarged goiter.
If there is at least one symptom, then you should already worry, and when there are two of them from this list, then it is definitely worth a diagnosis. As well as regular diagnosis, it is worthwhile to undergo those who have a history of immediate relatives who have thyroid tumors.
Diagnostic Methods
The most informative diagnostic methods will be the following:
- Ultrasound of the thyroid gland ;
- morphological examination (biopsy of a tumor fragment for cytological examination);
- blood test for thyroid tumor markers.
But separately, none of them is used for diagnosis. If a tumor is suspected, an analysis of tumor markers requires an ultrasound scan to detect the tumor itself and its exact location. If detected, a morphological study will be required to determine the degree of malignancy. And only then is a diagnosis made.
A uniform increase in size indicates pathological processes in the gland. Normally, the thyroid gland in women is no more than 19 cmÂł and 25 cmÂł in men. A cancerous tumor is characterized by an uneven outgrowth, which is seen on ultrasound.
Early diagnosis of the disease can save the patient’s life, because at the 1st and 2nd stages, the cancer is successfully treated, and the cases of healing at the 3rd are rare. At stage 4, doctors can do little, only prolong life and alleviate suffering.
Thyroid cancer informative markers
So which tumor marker shows thyroid cancer? Such tumor markers are hormones that the iron itself produces if it has a tumor or other degenerative changes. These are hormones such as calcitonin and thyroglobulin. Additionally, tumor growth indicates a level of cancer-embryonic antigen or abbreviated CEA.
The thyroid cancer marker calcitonin is produced by thyroid C cells. It is indicative of the diagnosis of a medullary type of cancer.
Thyroglobulin is produced by epithelial cells. A blood test for thyroglobulin is indicative only for papillary and follicular cancers. If you deviate from the norm, tests for the level of triiodothyronine and thyroxine (T3 and T4) will be indicative.
Each has its own specificity:
- The level of cancer-embryonic antigen increases with various locations of the cancerous tumor, including in the thyroid gland.
- Thyroglobulin levels usually increase with relapse of thyroid cancer.
- The hormone calcitonin rises with medullary thyroid cancer.
Analysis preparation
For the most reliable result, before passing an analysis on thyroid cancer markers, it is recommended to fulfill the following requirements:
- The analysis is given in the morning on an empty stomach. It is recommended to stop eating at least 8 hours before delivery, but you can drink some water.
- For 48 hours, any medication and dietary supplements, alcohol are stopped.
- For 24 hours, it is better not to eat spicy, salty and smoked.
- Do not overstrain and do not get nervous whenever possible, with stress hormonal disruptions occur.
- For a week, stop taking hormonal drugs.
If any requirements cannot be fulfilled, then the laboratory should be informed about this, he will make a note. For example, refusing to take any medication regularly carries a risk to life.
5 minutes before blood donation, pentagastrin is administered to the patient for calcitonin levels to stimulate.
Norms for women and men
The amount of thyroglobulin in the blood of a healthy person usually does not exceed 10 ng / ml, but a slight increase is not scary, since the norms are slightly higher. The norms of some hormones, for example, calcitonin in men and women can vary.
Tumor marker | Norm in the thyroid gland in men | Norm in the thyroid gland in women |
Thyroglobulin | From 2 mg / ml, but not more than 20 mg / ml, according to other sources, the norm is up to 60 mg / ml |
Calcitonin | 0.68–33 mg / ml, preferably closer to 8 mg / ml | 0.07-12.97 mg / ml |
Cancer-embryonic antigen (CEA) | No more than 5 ng / ml |
The norms are not the same; they differ in different laboratories. But, even after receiving an analysis with deviations from the norm, one should not panic.
Statistics show that people often go to the laboratory bypassing the doctor, focusing on the norms, but this is wrong. After all, as an isolated diagnostic method, it is useless.
But if this happened, then the analysis should be evaluated by an oncologist, who will diagnose or refute it, sending it for an additional examination. It is worth remembering that in the presence of a tumor, the indicators are likely to be overestimated significantly, 10, or even 20 times. A slight increase indicates more likely a malfunction in the thyroid gland.
About 10% of healthy people have elevated rates. During pregnancy, indicators can increase significantly and this is normal, since various hormonal changes occur. After breastfeeding, hormones should return to normal. With age and with inflammatory processes in the body, indicators also increase.
Advantages of analysis for tumor markers over other diagnostic methods
Is it possible to trust tests for tumor markers, if so many factors can affect their reliability? Like any diagnostic method, there are minuses and pluses, as well as a narrow focus.
Cons of visual diagnostics:
- There is a risk that the tumor will not be detected, especially at an early stage.
- A small dose of radiation or electromagnetic radiation.
There are one minus of tests for tumor markers, but serious - this is unreliability.
If we perceive the method not as the only one, but as an auxiliary one, then all claims to it will disappear, in its area of ​​responsibility the analysis copes quite well. As control of the resumption of growth of a removed tumor, analysis is indispensable. It also helps to monitor the effectiveness of treatment and the occurrence of relapses after removal of the tumor. But for preventive diagnosis, ultrasound is more indicative. There is a risk that the tumor has already begun to develop, and tumor markers will be negative.