Bone tumors. RMG: jan

Transcription

1 Bone tumors RMG: jan KIZZA JOHN KIJOHS

2 Diseases arising in bone Lipoma Fibrous cortical defects Non-ossifying fibroma Bone island Benign simple cysts Enchondroma Osteochondroma Osteoid osteoma Giant cell tumor Chondromyoxoid fibroma Chondromyxoid fibroma Chondrosarcoma Ewing s sarcoma Osteosarcoma Bone metastases *Osteomyelitis Metastasis, prostate cancer with mixed lytic and sclerotic pattern

3 Bone tumor description Age of patient Number of lesions Size Location Edge of the lesion Bone destruction Internal density or structure Periosteal reaction

4 Benign bone lesion Solitary 4cm lesion in distal shaft of tibia Narrow zone of transition Well defined, sclerotic margin Some internal septation No matric calcification No periosteal reaction Dx: Non-ossifying fibroma

5 Malignant bone lesion Solitary area of ill-defined bone destruction in upper fibular shaft of a 19 year old girl Permeative bone destruction with well-defined edge Wide zone of transition Soft tissue calcification adjacent to the bone lesion, with elevation of the periosteum inferiorly Dx: Ewing s sarcoma

6 Indeterminate bone lesion Solitary area of ill-defined bone destruction in proximal femur in a 55 year old man Edge of lesion not well defined. Some medial sclerosis Zone of transition narrow No visible internal structure No calcifications No visible periosteal reaction Dx: Chondrosarcoma

7 Lipoma of bone Unusual Specifically occur in calcaneus Well defined sclerotic edge Narrow zone of transition No periosteal reaction Central calcification due to necrosis of the fat in the middle of the mass Peak age: can occur at any age, mostly 30-60

8 Fibrous cortical defects Small areas of fibrous tissue extending into the cortex of the bone usually in the metaphyses of a child 2-10yrs, peak 7-8 Disappear but can be seen in adults Round or oval with all features of benign lesion (leave me alone lesion) May enlarge to form a non-ossifying fibroma

9 Non-ossifying fibroma Larger version of a fibrous cortical defect 8-20yrs (Peak: 10-20) More in the shaft than metaphysis probably reflecting growth of the fibrous cortical defect which started in the metaphysis Benign lesion, most of which disappear by themselves

10 Fibro-osseous lesion Non-ossifying fibroma Range of appearance AP: smooth hazy appearance of the tissue inside it which was not evident on the lateral Could be a focus of fibrous dysplasia and could just be called a fibro-osseous lesion (bone tissue has too much fibrous tissue in it)

11 Bone island Common lesions in adults of any age and in children to a lesser extent Consists of almost normal bone are benign Well defined dense areas often with small dense lines running into adjacent bone (brush boarder) Can be mistaken for sclerotic mets, but these tends to be large and less regular

12 Benign (simple) bone cysts Fluid filled benign lesions Start in metaphysis and may migrate in diaphysis with growth Expansion of bone with thinning of the cortex Commonly cause pathologic # # thru bone cyst may heal with complex septations. 3-20yrs for 80% of cases.

13 Fibrous dysplasia Areas of bone don t develop in normal bone forming cells, where there should be bone, is calcified fibrous tissue Has several forms. Can affect in just one small area (90% cases) or multiple areas Focal or wide spread areas with no bone trabeculae, instead, a smooth homogenous density (ground glass appearance) Bone often expanded. Cortical thinning may occur 3-15yrs Pathologic # +/-

14 Fibrous dysplasia, polyostotic (multiple bones) Uncommon form in wc multiple bones are affected Diffuse expansion of bone Evidence of previous pathologic #

15 Enchondroma Benign tumor of cartilage growing inside a bone Found incidentally or after pathologic # Occur anyway except the skull, commonly in small bones of hand feet Internal calcification, a feature of these tumors, may be the only part visible Usually left alone, but can change into chondrosarcoma, causing pain and swelling around previously asymptomatic lesion

16 Osteochondroma Benign cartilage tumor Grows outside the bone as a stalk of bone with a cartilage cup on top of it (imgae 1 next slide) or as a broad-base bone mass covered by cartilage (image 2 next slide) Lesions are usually bigger than they appear on x-ray cartilage partially calcified May be solitary or multiple (in a condition diaphyseal aclasis) Benign but can become malignant chondrosarcoma Should be suspected if known lesion start to grow rapidly and become bainful

17 Osteochondroma

18 Osteoid osteoma Unusual tumor which forms a dense sclerotic area of bone (white arrow), with a small central lucency (called nidus yellow arrow) The nidus may be small or hidden by an overlying dense bone. Cortical lesion may cause a benign periosteal reaction. These lesions are painful and tender Young adults, age range of 5-25 This is a benign condition which is cured by removing the nidus

19 Giant cell tumor Almost all affect the bone after the epiphysis has fused Mostly affect long bones and typically form low density areas which extent right up to the joint surface There may be internal septations as in cases 2 and 3 (next slide) Mostly age: 20-40yrs They cause pain and tenderness and have a risk of pathologic # 15% will become malignant with lung metastases Narrow zone of transition indicate benign, wider zone of transition suggests a malignant lesion. Biopsy and pathologic examination is required to make that dx. Image 3. next slide: expanding lesion of the upper end of the fibula looks like a simple cyst, perhaps with a few septations. But the age of the patient changes the likely dx as well as the other ddx A simple bone cyst is rare after the epiphysis

20 Giant cell tumor

21 Chondromyxoid fibroma Rare tumor affecting the shaft of the bone, and arising from cartilage It has benign features Note the well defined margin of the compartment within bone (white arrow), and the internal septa (yellow arrow) Peak age yrs

22 Chondrosarcoma Malignant tumor of cartilage It may go by itself as in patient 1 or arise in a preexisting benign tumor as in patient 2 (diaphyseal aclasis) Both these examples show extensive tumor calcification May be larger than visible coz of uncalcified cartilage The pelvis is a common site but can also occur in long bones Peak age range: 40-6oyrs and also occasionally in children

23 Ewing s sarcoma Commonest malignant bone tumor in children Peak age: 15yrs but has a wide age range Can behave in many ways like infection, with intense local pain, fever and raised WBC count Patient 1(next slide): typical features; Location in the diaphysis of the bone, Multiple bone destruction, Interruption yellow arrow feature of aggressive tumor and makes infection less likely Prominent periosteal reaction Periosteal rxn formed in layers at some points white arrow (lamellated / onion skin periosteal reaction) Patients 2 and 3(next slide): two variations in the pelvis Sclerotic in patient 2 with involvement of the whole lt ileum, note the associated soft tissue mass displacing the contrast filled UBL blue arrow, Lytic and expanding in patient 3

24 Ewing s sarcoma

25 Osteosarcoma (osteogenic sarcoma) Commonest primary malignant bone tumor in young adults Age peak: 10-25yrs Can occur in older patients especially radiation therapy or those with Paget's disease May present with pathologic # or local pain and swelling, fever Commonly occurs in metaphysis of long bone with knee region commonest site Bone destruction with ill defined margins, and wide zone of transition, irregular and interrupted periosteal reactiona nd new bone formation

26 Adductor magnus insertion, a normal variation May be concerned after seeing previous periosteal reaction Normal and medial metaphysis of the distal femur A large muscle, adductor magnus attaches in this area and can sometimes cause this irregularity (white arrow) in adolescents

27 Osteosarcoma Comes in many variations Pt 1. periosteal mass, destruction of underlying bone and a Codman triangle yellow arrow Pt 2. has a periosteal type which is which is seen in older patients and forms a dense mass completely outside the bone Pt 3. teenager with a pathologic # thru a Telangiectatic osteosarcoma, a very aggressive and highly vascular form

28 Three tumors Three female patients all with a similar lytic tumor in the distal femur. With slight variations of lesion margins, zone of transition, periosteal reaction (red arrow) and site Look similar apart from the patho # in pt 1 Pt 1: osteosarcoma, Pt 2: Giant cell tumor. Pt 3: condrosarcoma Point here; while the X-ray is a very important part of a dx tic process, there is enough of a range for each tumor that unless you see the classic features you will risk giving a misleading dx. Final dx of these malignant or possible malignant will always depend on combition of clinical hx, radiology and pathology

29 Bone metastases - sclerotic Commonest malignant bone tumor by huge margin Can be sclerotic in which new bone is made bcz of tumor cells, lytic in wc the tumor cells grow and destroy bone without any bone reaction, or mixed Sclerotic metastases in a man are more likely to be from a prostate carcinoma, and a woman from breast carcinoma, Other sites can be the cause Pt 1. bladder cancers with focal areas of increase density Pt 2. breast cancer with denser and more well defined lesions

30 Bone metastases - sclerotic Sclerotic mets can be very painful, but are often asymptomatic, and extensive Img1: sclerotic mets in a pt with bladder cancer seen in slide above. Generalized patchy increase in bone density throughout the tibia Img2: Prostate carcinoma mets causing generalized increase in the density of the ribs. There are some focal areas of sparing

31 Bone metastases - lytic Lytic mets carry a risk of pathologic # Common primary sites include; breast in women, and lung in men, with many others Pt1: lytic lesion in the humerus with malignant features already discussed. Though solitary, in a pt aged 60, metastases likely dx Img1c. Same lesion at an earlier stage, just beginning to erode the cortex (green arrow). Patient has lung cancer Pt2. has breast cancer. Ill defined areas of decreased bone density

32 Bone metastases - lytic 2 egs of mets in pelvic region Pt1: has thyroid cancer. 1a, lytic lesion above the acetabular roof (*), destructive lesion in the medial cortex ( ), lytic lesion with periosteal reaction lt anterior inferior iliac spine ( ). Img1b; 3 months later, lytic areas have joined together and expanded inferiorly Pt2: colon cancer with lytic areas in the femoral head (yellow star), acetabular floor (green arrows) Img 2b; growth of the yellow star lesion and new lesions formed in the proximal femur shown by orange arrows

33 Rib metastases Breast cancer with multiple lytic metastases in the ribs (white / yellow arrows) Yellow arrow lesions: diffuse bone destruction and associated extrapleural mass Blue arrow: expanding lytic lesion c a pathologic # An expanding lesion is most often associated with primary tumors of breast, kidney or thyroid. These shd be the organs to examine if a patient presents with an expanding bone metastes

34 Bone metastases - atypical Most bone metastases start centrally in the bone in the medullary cavity where the blood supply in richer and the bone is softer and easier to destroy. Pt1: metastasis in the cortex of the femur (white arrow) Pt2: metastatic nodule in the periosteum (yellow arrow). Both had lung cancer Pt3: expanding metastasis in the ischium (blue arrows) from bladder cancer. There are lytic areas as well ( red arrow)

35 Pathologic # thru metastasis Aggressive looking lesion, a metastasis from a sarcoma Ill defined bone destruction extends all the way between the white arrows There are small lytic areas further inferiorly, yellow arrows There is a crack # btn the blue arrows as the cause for the current pain. This was missed at the time, but very obvious when the patient returned 3days later

36 Assessing the risk of a pathologic # More likely in the lower limb than the upper, lytic lesions rather than sclerotic, and bigger rather than small. Pain is also a warning sign Lesion in a woman with breast cancer has a moderately aggressive appearance. Zone of transition is wide, on lateral; full thickness erosion of the anterior cortex c interrupted periosteal reaction (yellow arrow), dorsal cortex beginning to be eroded (blue). Pt at high risk of path #

37 Acute osteomyelitis, blood-borne Infection in bone Fever and local pain Periosteal reaction usually continuous, may be smooth or wavey. Images on next slide; findings are; Bone destruction (white arrow in pt, yellow arrow in pt2) Periosteal reactionblue arrows Soft tissue swelling Pt 3. thick periosteal reaction (red arrows) suggesting a slower process, lesser aggressive bacteria than patient 2. has bone destruction in anterior cortex (green arrow) rather than medullary cavity, as in pt2

38 Acute osteomyelitis, blood-borne

39 Chronic osteomyelitis If detected and treated, OM will resolve, if an treated will become cronic. Periosteum gets lifted off the cortex by pus which comes out of the medullary cavity along channels for blood vessels Periosteum thickens and makes new bone Bone itself has high pressure pus inside its medullary cavity, wc interferes with its blood supply Cortex dies. Thus new bone like structure outside the original bone, and a dead piece of bone inside, surrounded by pus and bacteria. More often condition becomes chronic Pus eventually breaks out thru a hole in the new bone and cause a drainage hole to form in the overlying skin (sinus).healing can not occur in this situation coz the dead bone surrounded by bacteria has no blood supply ABCs cant reach it to kill the bacterior

40 Chronic osteomyelitis

41 Chronic osteomyelitis the sequestrum Piece of dead bone floating in pus in the medullary cavity of the infected bone Treatment is to remove the sequestrum surgically Dense piece of a bone with a lucent area right around it. Its not attached to anything

42 Brodie s abscess If the battle btn the bacteria and the bone is not quiet so an even, a chronic abscess may occur inside the bone, without the death of cortex as seen above This is called a Brodie s abscess chronic low grade infection in the bone More common in children, in metaphyses as a well defined lytic lesion with benign features Pt 1 & 2 typical features