Pathology of bone tumour

2021-01-30 12:00 AM

Directional diagnosis based on clinical symptoms, X-rays, histopathology confirms diagnosis and classification.

Outline

Bone cancer is a malignant tumour stemming from the cells of the bone, the most common one is linked to bone formation and cartilage formation. This is a common cancer in teenagers and young adults. Boys meet more than women. In other ages, bone cancer is a rare type, the rate of about 0.5% compared to all cancers.

Cause and classification

Causes of bone cancer

Currently, the cause of bone cancer is completely unknown. There are a number of factors that are considered relevant but unproven factors.

Ionizing radiation: Is a physical agent from the external environment causing cancer. In the US, radiation-induced bone cancer accounts for 18% of all bone cancers.

Injuries: Impact from outside the bones, injuries that can result from sports activities; due to traffic accident. In clinical practice, there are some bone cancers that develop in the impacted area or fracture, especially the head on the tibia. In these cases, it is difficult to explain whether an accidental injury or the cause of the activation of over productive bone cells.

Inherited Disorders: An intrinsic factor linked to bone cancer. It is mentioned about this agent because bone cancer occurs at a young age, about 12-20 years old, this is the age when bones thrive, the time is too short for environmental-induced cancers to appear. . Bone cancer usually occurs in patients with cartilage buds growing at the junction of cartilage to long bone, this disease is considered hereditary disease. In patients with retinal cancer, which is considered an inherited cancer, bone cancer is also present. It is thought that due to a disorder of the P53 cancer suppressor gene, the body cannot control the cells with the mutation, causing these cells to continue dividing to create cancer cells.

Some benign bone diseases (which can turn into cancer):

Paget's disease of the bones.

Paget's disease can be seen in the breast and skin, especially in the bones of Paget's disease, causing cancer after 40 years of age.

Fibrocystic dysplasia of the bone.

Classification of bone cancer in organizational studies

Bone-forming cancer.

Cartilage-forming cancer.

Cartilage sarcoma.

Mesenchymal cartilage sarcoma.

Malignant giant cell tumours.

Sarcoma Ewing disease

Vascular cancer.

Extravascular cell carcinoma.

Peritoneal cell carcinoma.

Vascular sarcoma.

Bone connective cell carcinoma

Fibrosarcoma.

Fat sarcoma.

Malignant mesenchymal tumours

Other types of tumours:

U raw live.

Yeast tumours in long bones.

The frequency of occurrence of bone cancer varies, the most common being osteoporosis, according to Dahlon (1978).

Osteosarcoma 45%.

Cartilage sarcoma 25%.

Sarcom Ewing disease 13%.

Raw tumours 9% live.

Fibrosarcoma 7%.

Vascular sarcoma 1%.

Others 1%.

Diagnosis of bone tumour

Directional diagnosis based on clinical symptoms, X-rays, histopathology confirm diagnosis and classification.

Clinical symptoms

Patients are usually young: teenagers or young adults, aged 15-25 are most common, especially in children with a height higher than other children of the same age. The damage is mainly in the lower femur and upper tibial plateau, that is, the lower extremities are near the knee joint. Less common locations are the head above the femur and the head above the arm bone. The most common cancerous flat bones are the pelvis and shoulder blades.

Pain: Pain is the most common initial symptom. Vague pain in the bones and then soon showing obvious pain in short bursts, very uncomfortable. In the late stage of continuous pain, the patient groan, poor appetite, insomnia, common pain relievers, and anti-inflammatory analgesic drugs have almost no effect. Some patients refuse treatment at first, and later accept surgery because of the unbearable pain and complete loss of ability.

Tumour: May appear before, concurrently or after the initial pain symptom is a firm mass, pushes the surface of the skin, the edges are not clear, and is painless palpation. Later, it enlarges quickly, causing the tumour to deform. Soft tissue infiltration, blood vessels under the skin and new small blood vessels, painful on examination, skin colour becomes pink, warmer than elsewhere, density of soft, firm, stretchy due to hematoma. At this stage, the clinical picture is very similar to acute osteomyelitis, if not careful, it is easy to assign wrong surgery, late-stage tumours can infiltrate, break the skin, bleed, making the patient with superinfection anaemia. poor condition due to poor appetite, insomnia and pain.

Pathological fractures: Because cancer destroys bones, self-fracture phenomenon occurs, in some cases, it is easy to mistake normal fractures and even be cast or nailed to the bone marrow.

X-ray symptoms

The diagnostic key belongs to the X-ray image, normally it is necessary to take both straight and tilted films, taken from opposite sides to compare as possible, but note the following signs:

Locations of damage on bones: Types of bone-forming cancers and cartilage-forming cancers often appear at the junction of bone and cartilage of long bones. Ewing sarcoma, multiple bone marrow and malignant lymphoma are usually in the bone stem. Giant cell tumours are usually bone follicles or marrow at the ends of long bones.

Tumour margin: The tumour represents the growth rate of the tumour and the response of the surrounding organization. With benign tumours often have regular banks, thick, strong bones almost do not destroy the tumour margins. For benign tumours with progression or malignant tendencies such as giant cell tumours grade III and IV the tumour margins are very thin, weak, many sites are destroyed, there is no phenomenon of calcium formation around the tumour.

For osteoporosis and cartilage cancers do not see tumour margins or bone resorption, or create calcium in the soft tissue, the margins are wrinkled.

Osteoporosis Marks: Bone resorption is the standard marker of bone cancer. Depending on the type of tumour, bone resorption images are different. It can be seen in a cystic shape, a gag shape and a loss of calcium in the bone, and sometimes a picture of a fracture due to resorption.

Signs of bone formation by alternating with resorption: Very easy to confuse with osteomyelitis, but especially never signs of bone death.

Periosteal reaction: Periosteal reaction usually suggests bone cancer but is not specific. The periosteal reaction is usually thin, forming many leaves. In irregular periosteal cancer, periosteal breaks or no trace of the periosteal is visible due to the cancer invading soft tissue.

Diagnostic cytology

Diagnostic cytology with fine needles is a means of microscopic diagnosis for fast, convenient, and inexpensive disease identification. However, the appropriate ratio of a diagnosis of cytology to a histopathology of 55%, with 5% false positives, can overcome this problem by using a long, rigid needle suitable for bone tissue. and must have an expert read the template. While the above disadvantages cannot be overcome, cytological diagnosis must be prudent, negative cases do not negate the diagnosis.

Diagnosis of histopathology

The best histopathological diagnostic statement for bone cancer is fat biopsy, that is, knife biopsy, specimen sampling, 1cm3 for histopathological classification and histological grading. However, this method requires doing in the operating room because complications may occur due to bleeding after biopsy, sometimes emergency surgery is required.

Needle biopsy - cutting allows taking samples of sufficiently diagnostic specimens for this method, simple implementation, giving fast results compared to histopathological diagnosis reaching 85-87% without false positives, no variables symptoms, but the weakness is about 13%, still painful when puncture. In cases of unsatisfactory needle biopsy, immediate biopsy can be used during surgery or an open biopsy easily results after 48 hours. Thanks to the firm histopathological results prior to admission, physicians have enough time and information to discuss treatment plans with patients and their family members, especially in amputations.

Diagnosis of bone cancer metastasis

Pulmonary metastasis is an early metastasis of bone cancer, so it is necessary to take a lung scan to detect cancer that has metastasized in the lungs by blood, lung metastases often have glossy and nodular images, rarely due to pleural effusion. metastasis. Need liver ultrasound to find metastases. Metastatic form of jumping metastasis in bone cancer, for example tibial cancer jumped over the knee joint to the head under the femur.

In fact, there is about 10-20% of lung metastases at the time of diagnosis of bone cancer and many patients have lung metastasis within 6 months after treatment. It is the leading cause of death in bone cancer

Progressive stage diagnosis

Based on tumour classification (T), regional lymph nodes (N), distant metastasis (M) and differentiation of cells (G-Grading).

Primary tumour (T):

T0: the primary tumour is not found.

T1: The tumour has not been broken down.

T2: The tumour breaks the periosteum.

Regional ganglion (N):

N0: no regional lymph node metastasis.

N1: regional lymph node metastasis.

Distal metastasis (M):

M0: not far from metastasis.

M1: distant metastasis.

G: cell differentiation (Grading):

G1: Highly differentiated cancer.

G2: Moderate differentiated cancer.

G3: Low differentiated cancer.

G4: Cancer does not differentiate.

(Sarcom Ewing is in G4)

Stages: (1993 American Cancer Commission)

Stage Ia

G1,2

T1

N0

M0

Stage Ib

G1,2

T2

N0

M0

Stage IIa

G3.4

T1

N0

M0

Stage IIb

G3.4

T2

N0

M0

Stage IIIa

Any G

Any T

N1

M0

Stage IIIb

Any G

whatever T

Any N

M1

Stage rating (from Enneking et al. 1980)

Tumour (T)

T1: Tumour localized bone has not broken the periosteum.

T2: Widespread tumour disrupts the periosteal membrane.

Metastasis (M): regional metastasis and distant metastasis

M0: not metastasis.

M1: metastasis.

Cell differentiation (G)

G1: low malignancy.

G2: High malignancy.

Specifically, Enneking's staging is as follows:

Stage IA: G1T1M0.

Stage IB: G1T2M0.

Phase IIA: G2T1M0.

Phase IIB: G2T2M0.

Stage III: Any G, any T, has M1.

Differential diagnosis

Clinically, before tumour disease and radiographs with resorption and bone formation need differential diagnosis with the following diseases:

Osteomyelitis: Especially subacute and chronic inflammation.

Tuberculosis of the bones.

Healing bone tumours: Bone cysts, atherosclerosis.

Malignant lymphoma manifestations of bone.

The principles of treatment

Before 1970, bone cancer was a disease with poor treatment results. Most patients died from lung metastases. Since the 70s up to now, the world has achieved many remarkable progresses through the application of a combination of surgical and chemical treatment. Bone cancer is now considered treatable, with the results of life after 5 years from 60-70%. Chemotherapy plays a key role in altering the prognosis of bone cancer:

Chemotherapy for bone cancer

There are 2 chemotherapy methods (preoperative and postoperative) and many chemicals are used such as Cisplatin, Ifossamide, Adriamycin and especially high dose Methotrexate combined with folic acid has the highest response rate.

Chemical treatment before surgery

Chemical use before surgery within 3 months of the disease can be operated on the 8th day after the last methotrexate use. Chemical treatment before surgery has many advantages.

There is sufficient time and conditions to assess the response of cancer to chemicals by histopathology and tumour reduction to contribute to prognosis.

Control metastases that are undetectable when diagnosed.

Minimize primary tumour creates favourable conditions for limb-conserving surgery.

Chemotherapy is the time needed to prepare for conservative surgery (bone grafts, prosthetic replacements) or discuss the possibility of amputation with the patient.

It is usually more difficult for adults to accept high doses of methotrexate than it is for children. Therefore, the dose should not exceed 8g per square meter of skin. Methotrexate alone combined with folic acid resulted in a 35% response rate.

The current chemotherapy regimen is a combination of folic acid + methotrexate.

Vincristine, every 21 days and only use the drug on the first 3 days. Usage is as follows:

Vincristine 2mg / m2 day 1.

Methotrexate 3-7.5g / m2 day 1.

Folic acid 75mg / m2 day 1, 2 and 3.

All drugs are administered intravenously, particularly folic acid can be administered intravenously or oral. To limit the toxicity of Methotrexate, urine alkalizers can be used for easy detoxification. Firstly, infuse for 1/2-hour 500ml 1.4% bicarbonate salt solution. If the patient weighs no more than 25kg, only use 250ml of above solution. After that, the entire dose of Methotrexate mixed with 500 ml of 5% glucose infused continuously for 4 hours. Use of folic acid started 20 hours after taking Methotrexate.

In addition to the above regimen, AC regimen (Adriablastine / Cisplatine) and some other regimens can be used.

Chemical treatment after surgery

Chemical use after surgery has many disadvantages compared to preoperative, but nonetheless it still achieves the goal of reducing relapse in place, especially in conservative surgery and limiting distant metastases - drugs and usage are similar to the regimen outlined above.

Surgical treatment

Surgical treatment is necessary even in cases that respond to chemicals. According to some studies, without surgery, only 23% live 5 years without recurrence, even though the disease is completely recovered through chemicals. Meanwhile, the rate of chemotherapy and surgery is much higher.

Chiropractic surgery

Tumour resection and transplantation to restore lost bone or replace prosthetic bone. Indication: Cancer is localized, has not invaded the main nerves and blood vessels of the limb:

Cut off wide enough, 6-7cm from the u-shore.

Also organize the muscles to move, recreate the motor structure.

There is enough software and cover.

Skill:

Tumour resection: Cut the bone and organize the tumour wide enough to avoid recurrence.

Re-bone replacement: Replace prosthetic materials and bone graft of the same type.

Mechanical transfer and software cover.

Conservative surgery showed no reduction in survival but local recurrence by 3-10%. High postoperative complications: Broken graft and broken material fake infection and slow healing 20-30%, 50% of these cases need re-surgery.

Amputation surgery, removing joints

Children are young (due to the strong development of bones).

Chiropractic nerve damage.

No chemical response.

Biopsy in the wrong position makes it difficult to preserve surgery.

Infections, skin invasion.

Unable to open wide surgery, conservative surgery causes more loss of muscle function than amputation.

Metastatic drive surgery

After chemotherapy, if the lung metastasis is localized or concentrated on one side of the lung, the lobe or lung can be removed.

Radiation treatment

Depending on the type of cancer histopathology such as osteosarcoma, cartilage sarcoma, fibrosarcoma and is indicated for non-surgical cases. Local radiation at a dose of about 55-60 Gy has analgesic effects and slows the rate of tumour growth.

Ewing's sarcoma, vascular sarcoma, good Hodgkin malignant lymphoma, especially topical. But the survival rate over 5 years is still low, patients often die from distant metastases.

Prognosis

The prognosis of bone cancer depends on the following factors:

Location of Cancer: The far end of the limb is better than the proximal head.

Histopathology: Cartilage sarcoma and giant cell tumours.

 Treatment modalities:

Disease stage: Late-stage gives poor treatment result.

Preoperative chemicals combined with surgery for a good prognosis.

In general, with aggressive chemotherapy and surgery, 60-70% of spinal cancers are found after 5 years. Patients with chemical resistance and lung metastases have a poor prognosis.