Malignant Bone Tumors
What is it? One of several types of cancer affecting the bone, either primary or metastatic. These can cause pain in the bone, especially constant pain that seems to worsen at night.
PRIMARY BONE CANCERS:
-Multiple Myeloma (MM)- the most common primary bone cancer affecting 6 per 100,000 each year or about 30,000 people in the US newly diagnosed each year or 96,000 total living with the disease each year. MM affects primarily the spine, pelvis, and ribs, although it may affect any bone including the calvarium (skull) and may cause pain by fracturing bones or pressure development inside the bones due to an excess productions of plasma cells. It affects patients primarily age 50 to 70 but can be outside this bracket. MM is formed by malignant plasma cells (these are B lymphocytes that have transformed into plasma cells- part of the immune system). Multiple plasma cell tumor types is called MM. In MM there are low blood counts due to plasma cells crowding out normal cells from the bone marrow, and low platelet counts leading to bruising and bleeding and infections. MM sends a signal to the osteoclasts (a type of bone cell) to break down more bone, but doesn't send a corresponding signal to osteoblasts to make more bone, therefore the bone develops a "moth eaten look" or like a shotgun blast. Therefore with weakened bones, there is an increased risk of fractures. The antibodies made by the plasma cells in MM damage the kidneys through the production of amyloid- a combination of light chains of proteins produced by the plasma cells, and ultimately deposited in several organs making them dysfunctional. Only late does kidney damage show up in amyloidosis, sometimes only after the kidneys have failed. About 15,000 people a year in the US die from MM each year. Treatments are radiation and chemo. The 5 year survival is about 50%.
-Osteosarcoma (OS). This is the second most common bone cancer affecting up to to 5 per million population (1/10 that of MM) with 400 new diagnoses each year. , primarily teenagers and children. It is the most common primary bone cancer of children and teenagers. It is extremely rare before the age of 5. Blacks have a higher risk of developing this disease than whites. About 4% carry a gene to transmit this mutation and it may be associated with retinoblastoma (an eye tumor), multiple cancers, strong family history, after radiation treatment for other cancers. These malignant tumors primarily affect the femur, tibia, humerus, pelvis, and skull. It has metastasized 20% of the time when first diagnosed. Pain, swelling, decreased joint motion are common with fracture less commonly seen. Chemotherapy and surgery are the primary treatments. The 5 year survival is 76% for those younger than 15 and 66% for those older than 15.
-Ewing's sarcoma. This malignant bone tumor occurs after age 5 and before age 20 in most, involves the femur, tibia, pelvis, humerus, and ribs. The lower extremity is involved 41% of the time, the pelvis 26%, chest wall 16%, upper extremity 9%, spine 6%, and hand/foot 3%. However, Ewing's may develop primary tumors outside of the bone including in the trunk (32%), extremities (26%), head and neck (18%), retroperitoneum (16%). 25% of Ewing's patients have metastatic disease at the time of diagnosis. Typically it is treated with chemotherapy and surgery, or radiation. It is seen in one out of a million or about 225 children and teenagers in the US. Ewing's is 9 times greater in whites than in blacks. The disease may be localized, metastatic, or recurrent. It arises from a mesenchymal stem cell. The 5 year survival rate is 78% for those younger than 15 and 60% for those age 15-19.
-Chondrosarcoma. This malignancy of the cartilage is seen primarily in the hip, femur, pelvis, or shoulder, or the wide portion of the long bones. It occurs primarily in men between 60 and 80 years old and has an incidence of 5 per million- the same as osteosarcoma, but occurs in much older patients. It is the second most common primary malignancy of the bone, and there are several types of chondrosarcomas, depending on their origin, presentation, location within the bone, and the histological grade of the lesion. The pain is constant, not relieved by rest and interferes with sleep. There may be hip or knee pain as the first symptoms if it is located in the femur. Upper and lower extremity lesions als can cause weakness and disability in addition to pain. Surgery is the primary method of treatment since chemo and radiation have very little effect on some of the tumors. The 5 year survival rates depend on the histological grade: Grade 1: 90%, Grade 2: 81%, Grade 3: 29% , Undifferentiated 0%- the 1 year survival rate is < 10%.
METASTATIC BONE CANCER
Metastatic means the tumors arise from a distant source and invade the bone and bone marrow. The incidence of metastatic (secondary) bone cancer is much higher than primary bone cancer. The breast, prostate, lung, and kidney as primary sources of cancer are responsible for 75% of all cases of metastatic bone cancer. 70% of people with advanced prostate carcinoma or breast carcinoma have bone metastasis. Overall, 1.2 million cases of cancer are diagnosed each year in the US, and half of these tumors can spread to the bone. There is about four times the incidence of metastatic bone cancer compared to primary bone cancer. Metastatic bone disease is detected on MRI, PET scans, Bone scans, and CT scans.
Symptoms of Bone Metastasis:
- Bone pain may be the first symptom that cancer has spread to the bone, although there are many other common causes of bone pain that have nothing to do with cancer. The bone pain is intermittent at first, worse at night, and may improvement with movement. Later it becomes constant. It is sometimes a dull ache, sometimes like a bruise, sometimes sharp and intermittent depending on the person.
- Bone fractures may occur due to weakened bone that is infiltrated with cancer. The most common fractures are in the humerus (arm), femur (thigh), tibia (leg), and thoracic/lumbar spine. Infiltration of the vertebral bodies with metastatic tumors especially in the thoracic spine, lumbar spine, and sacrum may cause compression fractures.
- Spinal cord compression may cause loss of bowel or bladder control, pain in the back or neck, numbness or weakness below the level of the tumor. The tumor may infiltrate the spinal canal or may cause fractures of the vertebral bodies with subsequent compression of the spinal canal. The compression may occur suddenly and is a medical emergency.
- Elevated blood levels of calcium. When metastatic tumors infiltrate the spine, then the calcium in the bone is released causing elevated blood calcium that may cause serious illnesses including constipation, loss of appetite, extreme thirst, dehydration, muscle spasms, agitation, passing large amounts of urine, sleepiness, tiredness, weakness, irregular heartbeat, confusion, seizures, incoordination.
- Anemia and fatigue
TYPES OF METASTATIC CANCER
-Breast Cancer- 12% of women in the US will develop invasive breast cancer at some time during their lifetime. In 2016, there will be nearly 250,000 new cases of invasive breast cancer diagnosed and there will be 40,000 deaths from breast cancer. Of these initially diagnosed breast cancer, 10% will be Stage IV metastatic and 20-30% of recurrent breast cancer will be metastatic. Most of these are with bone metastasis (70%). There are approximately 155,000 women living with metastatic breast cancer in the US. The incidence is higher in blacks and the death rate is higher in blacks. Breast cancer is the number one cause of cancer deaths in women under age 50. Of all the breast cancers diagnosed, 1% are in men.
70% of breast cancer deaths are due to bone metastasis while 10% are due to brain metastasis. The most common sites for breast cancer bony metastasis are the spine, ribs, skull, pelvis, humerus, or femur.
The median survival rate from metastatic breast cancer is 36 months and the five year survival rate with metastatic breast cancer is 22%.
-Lung Cancer- Lung cancer is the leading cause of cancer death in the US with 46 deaths per 100,000. There are 224,000 new cases of lung cancer each year and 158,000 deaths from lung cancer. About 25% of all cancer deaths are due to lung cancer, and the number dying of lung cancer exceed the combined totals of colon, breast, and prostate cancer. Bone metastasis affect 30-40% of those with advanced lung cancer. The most common bones lung cancer spreads to are the spine (thoracic and lower abdomen), the pelvis, humerus and femur, and somewhat uniquely to the hands and feet (most cancers do not spread to the hands and feet). The pain is often worse at night especially when resting in bed. Compression fractures of the spine may occur and invasion of the spinal canal may result in spinal stenosis with weakness or tingling in the lower extremities when walking. The 5 year survival rate for early lung cancer before metastasis is 52% while metastatic lung cancer has a 5 year survival rate of 4%.
-Thyroid Cancer- Thyroid cancer metastasizes most commonly to the lung and to a lesser degree to the bone. There are 62,000 cases of thyroid cancer in the US each year with about 80% in women. There are 2,000 deaths each year from thyroid cancer. There are several types of thyroid cancers. On diagnosis of thyroid carcinoma, 5% will have bone metastasis. Papillary thyroid cancer is 70% of all thyroid cancers but only 1-7% develop bone metastasis. Follicular thyroid cancer has a much higher bone metastasis rate compared to other types of thyroid cancer. The 5 year survival rate for papillary or follicular metastatic thyroid cancer is 50%, for medullary metastatic thyroid cancer is 28%, and for anaplastic thyroid cancer is 7%.
-Kidney Cancer- There are 63,000 people in the US developing renal cell cancer each year and 14,000 die of the disease each year. Nearly 1/3 of patients with renal cell carcinoma will have bony metastasis on diagnosis and 40% of those with surgical resection of the primary tumor will have a relapse with bony metastasis. Following the lung, the bone in renal cell cancer is the second most common location of metastasis. The most common sites for metastasis are the pelvis and ribs (48%) followed by the spine (42%), then the long bones and skull. The overall 5 year survival rate for those with all stages of kidney cancer is 74% but for those with distant metastasis, the 5 year survival drops to 12%.
-Prostate Cancer- There are 181,000 new cases of prostate cancer each year and 26,000 deaths. 80% of the time the bony metastasis are to the hips, spine, and pelvis. There are over 2.8 million men living with prostate cancer in the US each year. The overall 5 year survival rate is 99%, however if there are distant metastasis, the 5 year survival rate drops to 29%.