3 types of Tumors of the bone, epidemiology, common bone involved, risk factors
Chondrosarcoma
- Chondroblast –> Cartilage
- Male > Female
- 30-60yo
- Pelvic bone, spine, shoulder girdle
Osteogenic sarcoma
- most common primary bone tumor
- male > female
- teenagers (1-25yo)
- higher risk: familial retinoblastoma
Ewing Sarcoma
- malignant neoplasm of undifferentiated cells arising within marrow cavity
- male > female
- teenager (5-20yo)
Clinical presentation of osteosarcoma
involves Metaphyses of long bone
common bone:
- distal femur, proximal tibia around the knee (50%)
- Pelvic girdle, shoulder joint, jaws
Large firm, white-tan mass
w necrosis & haemorrhage
Clinical features
Outward spread from medullary cavity, infiltrating throught cortex, lifting the periosteum
=> Periosteal elevation (Codman Triangle)
Sun-burst pattern (spiculated pattern from calcified malignant osteoid) -> rapid tumor growth
Bone destruction
Clinical features of Ewing Sarcoma + fav bones
Femur, pelvis, TIbia
Also white-tanned mass w necrosis and haemorrhage
Pain, swelling, tenderness
Concentric onion skin layering of periosteal bones
Types of anemia !! (link to etiology)
- Decrease production of RBC
- Nutritional deficiency: Iron, Vitamin B12, Folate
(iron deficiency is the most common anemia) - Renal failure (erythropoietin)
- Aplastic anemia (mostly due to auto-immune)
- Increase destruction of RBC (Hemolysis)
- inherited: Thalassemia (defective Hb), sickle cell, spherocytosis
- non-inherited: immune or non-immune mediated destruction
- Blood loss
- acute vs chronic loss - Combination of 1-3
Normal Hb value for male and female
Male: Hb <13.5 / Female: Hb <12
Types of anemia (morphology)
Normocytic anemia: Uniform size, lesser cell/volume
- acute blood loss
- aplastic anemia
- hemolytic anemia
Microcytic anemia: Central pallor, various size (anisocytosis), various shape (poikilocytosis), target cells
- Iron deficiency anemia
- thalassemia
Macrocytic anemia: Larger than normal, Anisocytosis, Poikilocytosis
- Vitamin B12 deficiency (maturation)
- Folate deficiency (maturation)
Thrombocytopenia - abnormal range
<100,00 platelets / uL - clinically significant
<50,000 platelets / uL - risk of spontaneous bleeding w min trauma
< 15,000 platelets / uL - spontaneous bleeding wo trauma, fatal
TRO pseudo thrombocytopenia
Haemophilia - types, clinical features
Congenital cause of coagulation disorders
- sex-linked recessive disorders, mainly affect males
80% - haemophilia A (deficiency in factor VIII) **
20% - haemopilia B (deficiency in factor IX)
Similar clinical features, tendency to bleed, joint deformities due to blood in cavity
Von Willebrand’s disease - what is it
most common inherited coagulation disorder
deficiency of von Willebrand factor (vWF)
–> platelet unable to bind to damaged blood vessels wall
4 acquired causes of coagulation disorders
Dietary insufficiency - Vitamin K, protein
Liver - produces clotting fators
Anticoagulant therapy - warfarin, heparin
** Disseminated Intravascular coagulation - most commonly caused by infection
Classification of leukemia
By onset
- Acute, Chronic
By cell of origin
- Lymphocytic, Myelocytic
4 types of leukemia
- their appearance on microscope/description
- age grp
- organ involvement / symptoms
- disease progression
ALL
- Children, young adults, <20yo
- Blast cells on peripheral blood smear or bone marrow aspirate
- accumulation of lymphoblasts in body organs ie. liver, cns, thymus
AML
- Adults
+ Auer rods on peripheral smear (myeloblast cytoplasm)
- genetic abnormalities: Chromosome 8, 16 –> affects treatment plans
- lymphadenopathy, splenomegaly less prominent
CLL
- Elderly >65yo
- Chromosome 11, 13, 17
- Clonal expansion of at least 5000 B lymphocytes per uL of peripheral blood
- mainly B cells are affected, more well differentiated cells –> might not need treatment
- usually asymptomatic –> lymphadenopathy, hepatosplenomegaly –> (10%) autoimmune hemolytic anemia
CML
- Adults (25-60yo)
- Presence of Philadelphia chromosome (BCR-ABL1 fusion gene) (chromosome 9 & 22)
- Asymptomatic –> anemia, neutropenia
- Abdo discomfort, hepatosplenomegaly due to myeloblast infiltrating liver & spleen
- may transform into acute leukemia (blast crisis)
Leukemia - general epidemiology
malignacy arising from bone marrow stem cell
male > female
Leukemia - risk factors
Chromosomal abnormalities (Down syndrome)
Viral infection (HIV, EBV)
Carcinogen exposure
- Benzene
- smoking
- chemo, ioninsing radiation.. rt..
Pathophysiology of acute leukemia
- abrupt onset, rapid progression
malignant myeloblasts or lymphoblasts multiple in BM –> eliminate normal tissue in BM
–> bone marrow suppression (pancytopenia)
–> bone pain due to marrow expansion, periosteal infiltration
Malignant cells accumulates in organs, esp in ALL
- Generalised lymphadenopathy
- Hepatosplenomegaly
- Thymus
- CNS
Resulting in symptoms of pancytopenia + CNS manifestations
(headache, vomiting w no nausea, nerve palsies)
pathophysiology of chronic leukemia
Proliferation of fully differentiated lymphoid and myeloid cell (more mature cells)
Gradual onset, milder S&S
