Bone marrow cancer: causes, symptoms, diagnosis, treatment

Oncological disease of myeloid (hematopoietic) tissue is classified as hemoblastosis, and this is actually bone marrow cancer. It should be noted that cancer cells from the bone marrow are capable of affecting bone tissue, and then various forms of bone cancer develop. And they can cause oncological blood lesions.

When speaking about bone marrow cancer, specialists mean an oncological disease of the most important hematopoietic organ of a person, which is located in the spongy tissue of bones (the end sections of long tubular bones and the cavities of many spongy bones, including the bones of the pelvis, skull, sternum). It is the special cells of the myeloid tissue of the bone marrow - hematopoietic stem cells - that synthesize leukocytes, platelets, erythrocytes, as well as eosinophils, neutrophils, basophils and mononuclear phagocytes. Bone marrow does not synthesize lymphocytes, but it contains B-lymphocytes, which recognize genetically foreign substances (antigens) in our body, begin to produce protective antibodies and "release" them into the blood, ensuring the functioning of the immune system.

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Causes of Bone Marrow Cancer

Numerous studies into the causes of bone marrow cancer have shown that bone marrow is rarely affected separately from other organs. A much more common situation is when bone marrow becomes the target of metastases. According to oncologists, cancer metastases to bone marrow are most often observed in patients with malignant neoplasms of the lungs, thyroid gland, mammary glands, prostate gland, and also in childhood neuroblastoma (cancer of the sympathetic nervous system). In the latter case, metastases to bone marrow occur in more than 60% of patients. While metastases of cancer to bone marrow in malignant tumors of the colon occur in only 8% of cases. Dissemination (spread) of cancer cells from the primary tumor site occurs through blood and lymph, and thus uncontrollably multiplying cancer cells enter the bone marrow.

However, there is also primary bone marrow cancer, the true causes of which are currently unknown. Factors such as infections, harmful chemicals or other adverse environmental influences may play a role in the development of bone marrow cancer, but there is no strong evidence of this. There are also no well-founded arguments that there is a hereditary factor.

Most researchers tend to see the causes of bone marrow cancer in somatic mutation of plasma cells - the main cells that produce antibodies and are the final stage of B-lymphocyte development. According to this version, bone marrow cancer - bone marrow sarcoma or myeloma disease - occurs due to the destruction of myeloid tissue, which occurs due to excess plasma cells. Sometimes plasma cells can completely displace normal hematopoietic tissue from the bone marrow.

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Symptoms of Bone Marrow Cancer

Bone marrow cancer, as medical statistics show, mainly affects men after 50 years of age, but can also develop in younger people. The disease has two forms: with one focus (solitary) and multiple (diffuse).

Domestic and foreign oncologists point out the following main clinical symptoms of bone marrow cancer:

• anemia, in which a person quickly gets tired, complains of weakness and dizziness. Sometimes anemia is the very first and main manifestation of the disease;
• persistent pain in the bones that intensifies with movement (most often in the lower back, pelvis and rib area);
• bruises on the body and bleeding gums (blood clotting problems associated with low platelet levels);
• compression of the spinal nerve endings, which is expressed in weakness of the leg muscles, numbness of individual parts of the body or legs, pain in the bladder or intestines and problems with emptying them;
• increased thirst, nausea, vomiting, constipation (indicate high levels of calcium in the blood - hypercalcemia);
• nosebleeds, blurred vision, headaches, drowsiness (associated with increased blood viscosity due to very high levels of an abnormal immunoglobulin protein - paraprotein);
• sites of damage to the bone marrow and bones (pelvis, ribs, sternum, skull, less often - long bones) in the form of holes of various sizes, but invariably round in shape with clear boundaries;
• swelling over the site of the tumor.

With the diffuse form of bone marrow cancer (myeloma), the following symptoms are observed:

• progressive normochromic anemia, exhaustion, weight loss;
• bone pain;
• the size of single lesion nodes increases and merges, causing thickening of bone tissue;
• systemic osteoporosis, i.e. a decrease in bone density and strength (may be accompanied by pathological fractures);
• the lesion spreads to the spine, causing its curvature (thoracic kyphoscoliosis);
• susceptibility of patients to bacterial infections due to a significant decrease in immunity (due to hypogammaglobulinemia).

Stages of bone marrow cancer

At the first, and often at the second stage of bone marrow cancer, this disease is rarely diagnosed, since patients mistake the pain that torments them for radiculitis, and doctors - for osteochondrosis, rheumatism, arthritis or primary radiculoneuritis. If patients consult a urologist about kidney problems, they are immediately suspected of having urolithiasis or pyelonephritis. And only on ultrasound are local pathological lesions of bone tissue detected.

The last stage of any oncological disease is considered to be a condition when the tumor has metastasized to the lymph nodes and other organs. Stage 4 bone marrow cancer is an extensive bone marrow sarcoma with metastases or a diffuse form of myeloma disease.

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Diagnosis of bone marrow cancer

It is clear that the symptoms of bone marrow cancer cannot be the only basis for diagnosis. Moreover, diagnostics must be differentiated. Laboratory analysis of blood (biochemical and determination of IgM antibodies in the blood), urine, feces, as well as histological examination of particles of affected tissue (biopsies) and biochemical analysis of myeloid tissue (bone marrow puncture) are necessary.

In the diagnosis of bone marrow cancer, radiological methods, bone scintigraphy, computed tomography (CT) and magnetic resonance imaging (MRI) are necessarily used.

In 97% of patients with bone marrow cancer, blood and urine protein tests are abnormal.

Blood analysis for bone marrow cancer is very specific. Thus, the color index of blood (i.e. the relative content of hemoglobin in one erythrocyte) is close to one (with the norm being 0.85-1.05). ESR indicators are elevated. A change in the shape of erythrocytes (poikilocytosis) characteristic of anemia is detected, as well as a significant difference in the size of erythrocytes in the same person (anisocytosis) with a large percentage of abnormally small erythrocytes (microcytosis).

In the blood of patients with bone marrow cancer, the number of nuclear forms of erythrocytes and erythroblasts (intermediate cells in the development of red blood cells) is increased. The number of reticulocytes (young erythrocytes that are formed in the bone marrow and circulate in the blood) is also higher than normal. But the content of platelets in the blood test for bone marrow cancer is significantly lower than the normal level.

To confirm the diagnosis, a histological analysis of the bone marrow is performed - a biopsy (trepanobiopsy), and the myelogram compiled based on its results allows for an objective assessment of the condition of the bone marrow cells.

Treatment of bone marrow cancer

Treatment of bone marrow cancer depends on the form of the disease. In the solitary form of myeloma, the main method of treatment is surgical, in which the lesion is removed.

Symptomatic treatment is also prescribed, which is aimed at relieving pain (taking painkillers); strengthening bones (bone tissue protectors - bisphosphonates); increasing the content of red blood cells in the blood (steroid hormonal agents).

To improve the composition of patients' blood and reduce the level of paraprotein in it, exchange transfusion or membrane plasmapheresis can be used.

If the lesions are solitary, a course of radiation therapy is administered. In diffuse myeloma, various chemotherapy regimens are used to stop the proliferation of cancer cells.

Stem cell transplantation may be an option for treating bone marrow cancer. This treatment is not suitable for all cases, but it offers a better chance of complete remission. Stem cells are usually obtained from the blood of a patient with cancer before radiation or chemotherapy.

The total duration of treatment for bone marrow cancer until remission can be about a year. In many cases where there is partial remission, the disease returns at some point (relapses). Over time, treatment of relapses becomes more complex and difficult.

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Prevention of bone marrow cancer

It should be noted that decreased immunity plays an important role in the development of bone marrow cancer. Therefore, to provide the body with substances useful for bone marrow, it is recommended to eat:

• fatty sea fish (as a source of essential fatty acids);
• chicken (proteins, selenium, B vitamins);
• walnuts (iron, cobalt, copper, iodine, zinc, manganese and polyunsaturated fatty acids);
• peanuts (arachidonic acid);
• chicken eggs (lutein);
• seaweed (iodine).

Correcting hypercalcemia properly is very important, so people diagnosed with bone marrow cancer (myeloma) are usually advised to drink plenty of fluids - at least three liters a day. This helps to reduce high calcium levels.

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Bone marrow cancer prognosis

Most often, the prognosis for bone marrow cancer is unfavorable. Although with primary solitary myeloma without metastases, the survival rate of patients is 75-80%. In most cases, osteogenic tumors lead to death, that is, when cancer cells from the bone marrow penetrate the bones and cause bone cancer (osteogenic sarcoma, chondrosarcoma, chordoma, Ewing's sarcoma, etc.).

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How long do people live with bone marrow cancer?

In general, if detected and treated early, about half of people live 3-4 years. In some cases, the disease responds very well to treatment, and survival is much higher. In particular, a successful stem cell transplant gives a good chance of complete remission of bone marrow cancer.