diease

Bone Cancer


OVERVIEW OF Bone Cancer :

 Bone cancer is the type of cancer which develops in the bone and bone marrow.


STRUCTURE of Bone Cancer :

Bone is the supporting framework for your body. The hard, outer layer of bones is made of compact (cortical) bone, which covers the lighter spongy (trabecular) bone inside. The outside of the bone is covered with fibrous tissue called periosteum.

Some bones have a space inside called the medullary cavity, which contains the soft, spongy tissue called bone marrow. The tissue lining the medullary cavity is called endosteum.

Most bones start out as a softer, more flexible form of tissue called cartilage. Cells in the body then lay calcium down onto the cartilage to form bone. After the bone is formed, cartilage may remain at the ends to act as a cushion between bones. This cartilage, along with ligaments and other tissues connect bones to form a joint. In adults, cartilage is mainly found at the end of some bones that are part of a joint.

The bone marrow contains the fatty tissue and also the blood forming cells. The cells that are formed from the bone marrow includes red blood cells, white blood cells, platelets, plasma cells and fibroblasts.

The bone cells consists of two types of cells which are known as

Osteoblast – bone forming cells

Osteoclast-bone resorbing cells.


CAUSES :

Age

Familial history/ genetics

Inflammatory bowel disease- ulcerative colitis and crohns disease

Chronic exposure to radiation

Smoking

Alcohol consumption

Ingestion of higher amount of NSAIDs

Ebstein barr virus


PATHOPHYSIOLOGY :

Benign bone tumours:

  • Osteochondroma is the most common. It often happens in people under age 20.
  • Giant cell tumor is usually in your leg. In rare cases, these can also be cancerous.
  • Osteoid osteoma often happens in long bones, usually in your early 20s.
  • Osteoblastoma is a rare tumor that grows in your spine and long bones, mostly in young adults.
  • Enchondroma usually appears in bones of your hands and feet. It often has no symptoms. It’s the most common type of hand tumour.

Primary tumour:

  • Osteosarcoma: It often forms around your knee and upper arm. It might also occur in paget’s disease of bone.
  • Ewings sarcoma: It usually happens in people between the ages of 5 and 20. Your ribs, pelvis, leg, and upper arm are the most common sites. It can also start in the soft tissue around your bones.
  • Chondrosarcoma: happens most often in people between ages 40 and 70. Your hip, pelvis, leg, arm, and shoulder are the common sites of cancer


COMMON CLINICAL SIGNS AND SYMPTOMS :

  • Bone pain
  • Weakness and fatigue
  • Weight loss and loss of appetite
  • Upset stomach
  • Constipation
  • Confusion
  • Frequent infections
  • Severe thirst
  • Weakness or numbness in your arms and legs


DIAGNOSTIC :

Bone cancer takes place in the bone cells. This result in the activation of the osteoclast which result in the resorption of the bone and suppress the activity of the bone forming cells that is the osteoblast. Bone cells cells initiates the cytokines production which in turn increases the osteoclastic activity.

The osteoclastogenic activating factors include RANKL, MIP-1α, TNF-α, Interleukin 3 (IL-3), and IL-6, Ephrin B 2, Annexin.

Adhesive interaction of the bone cells and stromal cells results in the activation of the  RANKL which in turn increases the osteoclastic activity of  the cells.

Diagnosis of Bone Cancer:

Blood test:

The routine blood test is done to look  for the anaemia, lymphocytosis and other cell count.

Blood chemistry tests:

Creatinine: high amount of creatinine indicates that the kidney is not functioning properly.

Albumin: low amount of this protein in blood indicates bone cancer.

Calcium: since the patient with bone cancer tends to have increase in the bone resorption the blood calcium levels are increased in them.

Lactic dehydrogenase: it is the metabolic product and the rise in LDH indicates that the disease has worst prognosis.

Urine test:

The urine test is indicated to check for the proteins. These test are also known as protein electrophoresis and urine immunofixation.

Quantitative immunoglobulins:

This test measures the blood levels of the different antibodies. The antibodies include IgA, IgD,IgG,IgM.

 

Bone marrow aspiration:

In bone marrow aspiration, the back of the pelvic bone is numbed with local anesthetic. Then, a needle is inserted into the bone, and a syringe is used to remove a small amount of liquid bone marrow. This causes a brief sharp pain. For the biopsy, a needle is used to remove a tiny splinter of bone and marrow. Patients may feel some pressure during the biopsy. There is some soreness in the biopsy area when the numbing medicine wears off. Most patients can go home immediately after the procedure. This test can be useful in multiple myeloma causes.

The bone marrow tissue is examined in the lab to see the appearance, size, and shape of the cells, how the cells are arranged and to determine if there are myeloma cells in the bone marrow and, if so, how many. The aspirate (the liquid part of the bone marrow) may also be sent for other tests, including immunohistochemistry and flow cytometry, and chromosome analyses, including karyotype and fluorescent in situ hybridization (also known as FISH).

Immunohistochemistry: a part of the biopsy is treated with special proteins which causes some colour change and it is useful for detecting the bone cancer.

Flow cytometry:

A sample of bone marrow is treated with special proteins that stick only to certain cells.

Cytogenetics:

This test evaluates the chromosome in normal bone marrow cells and in myeloma cells. Chromosomal abnormalities such as deletions, translocations , abberations can be detected.

Fluorescent in situ hybridization(FISH):

It uses special fluorescent dyes that only attach to specific parts of chromosomes. It can find most of the chromosomal changes.

Fine needle aspiration (FNA) biopsy:

A needle is used to aspirate small fragments of tissues. It is used for cancer in the lymph node in the lungs.

Other imaging test:

Bone Xray:

The x ray predicts any abnormal area in the bone

Computed tomography:

It reveals the slice of the bone. It uses both the combination of x ray and computer aided device.

It helps to analyse the size, shape and position of any lung tumour and also it helps in the detection of enlarged lymph nodes.

It also looks for any masses in the adrenal gland, liver, brain and other organs.

 CT guided needle Biopsy:

CT scan might be used to guide a biopsy needle into this  area to get the tissue for bone cancer.

MRI scan:

It uses the soft tissue image of the organ. It uses the both the magnet and radiowaves.

It often reveals whether the cancer cells has spread to the brain or spinal cord.

Positron emmisison tomography:(PET)

 A radioactive form of sugar in injected into the blood and the positron are emitted to reveal the cancer site.

They can detect if the cancer cell has spread anywhere.

Bone scan:

A low level radioactive material is injected into the blood and collects mainly in abnormal areas of bone and resorption areas in bone can be viewed.

1. At least one of the following:

  • High blood calcium level
  • Poor kidney function
  • Low red blood cell counts (anemia)
  • Holes in the bones from tumor found on imaging studies (CT, MRI, PET scan)
  • Increase in one type of light chain in the blood so that one type is 100 times more common than the other
  • 60% or more plasma cells in the bone marrow

 


TREATMENT AND PROGNOSIS :

  • Limb salvage surgery. Your doctor removes the part of the bone with cancer but not nearby muscles, tendons, or other tissues. They put a metallic implant in place of the bone.
  • Amputation. If a tumor is large or reaches your nerves and blood vessels, your doctor might remove the limb. You may get a prosthetic limb afterward.

 

  • Chemotherapy:
  • A chemotherapy is after the sugery or before the surgery to shrink the cancer cells. A chemotherapy is nothing but the delivery of drug intravenously
  • Radiation therapy:
    • It uses powerful x rays or emission of protons to destroy the cells. The radiation therapy also aids  in shrinkage of the cells and also relief the symptoms caused by the cancer.

 

  • Immunotherapy
    • it is a drug treatment that uses your immune system to fight cancer. Your body's disease-fighting immune system may not attack your cancer because the cancer cells produce proteins that blind the immune system cells from recognizing the cancer cells. This immunotherapy boos those cells and helps the body to fight against it.
    • Drugs used: Thalidomide, lenalidomide, and pomalidomide
  • Targeted therapy:
    • This therapy involves targeting the specific organs. It involves the emission of rays.
  • Steroid therapy:
  • Prednisone or Dexamathasone can be given to reduce the effect of plasma cells.
  • Bone modifying cell:

              These drugs are used to strengthen the bone. Drugs: zoledronic acid  and pamidronate, Denosumab

 

 


PROGNOSIS :

The early 5 year survival rate is 75% and to the distant spread is 53%.


PREVENTION :

Avoid smoking

Avoid air pollution areas

Avoid the exposure to the radiation and chronic chemicals

Follow healthy diet


Medicines used in the Treatment :

cyclophosphamide,

 doxorubicin

 cisplatin

carmustine