Tumores e lesões tumorais benignas - Parte 3

Tumores e Lesões Tumorais

Benignas Lesões Fibrosas, Fibro-ósseas e

fibro-histiocíticas

Dr. Emanuel R. Dantas Médico Radiologista – Membro Titular do CBR

Defeito Cortical Fibroso e Fibroma Não Ossificante

•  Os DCF e FNO são as lesões fibrosas mais comuns do osso, observadas predominantemente em crianças e adolescentes.

•  Localização: ossos longos, particularmente fêmur e tíbia

•  Não são neoplasias verdadeiras, mas defeitos embriológicos.

Dr. Emanuel R. Dantas


•  O DCF é uma pequena lesão assintomática encontrada em 30% das pessoas normais na 1 e 2 décadas de vida.

•  Aparência Radiológica: o  Radiotransparente, elíptica e limitada à cortical de um osso

longo próximo à placa de crescimento o  É demarcada por uma margem fina de esclerose.


Fibrous cortical defect. Fibrous cortical defect, seen here in lateral cortex of the distal tibia in a 13-year-old boy, typically presents as a radiolucent lesion demarcated by a thin zone of sclerosis.


Fibrous cortical defect. A 21-year-old woman with a fibrous cortical defect affecting medial cortex of the distal femur.



•  A maioria dessas lesões desaparece espontaneamente, mas algumas podem continuar, e quando invade a medular de um osso, são designadas de FNO.

•  Com o crescimento contínuo, estas lesões excêntricas no osso, exibem uma características borda esclerótica recortada.


Nonossifying fibroma. When a fibrous cortical defect encroaches on the medullary cavity, it is called a nonossifying fibroma. Note the similarity of the lesion to that in the previous figure. The only difference is that the fibroma is larger and extends beyond the cortex



•  A maioria da lesões sofre involução espontânea (cicatrização) por esclerose ou remodelagem.

•  Complicação: fratura patológica no caso de lesões maiores.

•  Diagnóstico Diferencial: Histiocitoma fibroso benigno


Healing of nonossifying fibroma. (A) Spontaneous involution of nonossifying fibroma in the distal tibia is characterized by progressive sclerosis of peripheral parts of the lesion. (B) A nonossifying fibroma that healed completely may persist as a sclerotic patch. Nonossifying fibromas in this sclerosing phase should not be mistaken for osteoblastic tumors or for sclerosing dysplasia


Complication of nonossifying fibroma. Pathologic fracture is a common complication of a large nonossifying fibroma, as seen here in the distal tibia of a 10-year-old boy. Lesions extending halfway or farther into the medullary region of a bone should be treated by curettage and bone grafting.


Histiocitoma Fibroso Benigno

•  Termo utilizado para subclassificar lesões com aspectos radiológicos semelhantes ao do FNO, mas que possuem uma apresentação clínica atípica.

•  Sua diferenciação com FNO é feita puramente em bases clínicas, pois histologicamente são quase idênticos.

•  Clínica: podem produzir dor ou desconforto no osso envolvido (FNO são assintomáticos).


Histiocitoma Fibroso Benigno

•  Faixa etária: > 25 anos (mais velhos que os do FNO).

•  Aparência: Radiotransparente, com bordas bem definidas e freqüentemente escleróticas, sem qualquer mineralização da matriz.


Benign fibrous histiocytoma. A 37-year-old man presented with occasional pain in the right knee. Oblique radiograph of the knee demonstrates a lobulated radiolucent lesion with a well-defined sclerotic border, located eccentrically in the proximal tibia. Biopsy revealed benign fibrous histiocytoma.


Displasia Fibrosa •  Caracterizada pela substituição de osso

esponjoso lamelar normal por um tecido fibroso anormal.

•  Pode afetar um osso (forma monostótica) ou vários ossos (forma poliostótica).


Displasia Fibrosa Monostótica

•  Afeta mais comumente o fêmur (particularmente o colo), bem como tíbia e costelas.

•  No osso, origina-se centralmente, geralmente poupando epífises.

•  Aspecto Radiológico: o Varia a depender do conteúdo ósseo-fibroso. o Maior conteúdo ósseo: densas e escleróticas o Menor conteúdo ósseo: mais radiotransparentes, com

aspecto de VIDRO FOSCO característico.


Monostotic fibrous dysplasia. (A) Typically, the focus of fibrous dysplasia is located in the femoral neck, as seen here in a 13-year-old girl. Note a characteristic sclerotic “rind” encapsulating the lesion. (B) The rib is a frequent site of fibrous dysplasia. Note the expansive lesion exhibiting a ground-glass appearance. Dr. Emanuel R. Dantas

Monostotic fibrous dysplasia. Oblique (A) and lateral (B) radiographs of the left leg of a 32-year-old woman demonstrate a large, trabeculated radiolucent lesion in the distal tibia. Because of its aggressive features, it was thought to be a desmoplastic fibroma; however, biopsy proved it to be a fibrous dysplasia, a rare lesion at this site in adults.


Monostotic fibrous dysplasia. Anteroposterior radiographs of the left humerus in neutral (A) and external rotation (B) projections of a 13-year-old boy show a radiolucent focus of fibrous dysplasia in the diaphysis of the bone.


Displasia Fibrosa Poliostótica

•  Radiologicamente semelhante à forma monostótica.

•  Lcalização: diferente da forma monostótica e predileção surpreendente por um lado do corpo: o  A pelve é freqüentemente

afetada, seguida pelos ossos longos,crânio e costelas



•  Aparência radiológica: o Como na forma monostótica, as extremidades

articulares são preservadas. o A cortical é freqüentemente adelgaçada pelo

componente expansivo da lesão,mas permanece intacta.

o Como na forma monostótica, a substituição do osso medular por tecido fibroso leva a perda do padrão trabecular à aspecto em VIDRO FOSCO.


Polyostotic fibrous dysplasia. A 13-year-old girl injured her right hip. (A) A radiograph of the hip, obtained to exclude a fracture, demonstrates a silent focus of fibrous dysplasia in the femoral neck. To determine other sites of involvement, a radionuclide bone scan was obtained. In addition to the focus in the femoral neck (B), increased uptake of isotope was demonstrated at various other sites, but predominantly the right leg


Subsequent radiograph of the right lower leg in the anteroposterior projection (D) confirms the presence of multiple foci of polyostotic fibrous dysplasia.



•  Complicações: o Mais freqüente: fratura patológica. Se ocorrer no colo

do fêmur à “cajado de pastor”. o Hiperplasia acentuada da cartilagem à acúmulo de

massas cartilaginosas na porção medular do osso afetado.

o  Transformação sarcomatosa


Polyostotic fibrous dysplasia. A “shepherd's crook” deformity, seen here in the proximal femur in a 12-year-old boy with polyostotic fibrous dysplasia, is often the result of multiple pathologic fractures.


Fibrocartilaginous dysplasia. An anteroposterior radiograph of the proximal right femur of a 10-year-old boy with polyostotic fibrous dysplasia exhibits typical appearance of a massive formation of cartilage, known as fibrocartilaginous dysplasia


Fibrocartilaginous dysplasia. (A) An anteroposterior radiograph of the left humerus in a 19-year-old man with polyostotic fibrous dysplasia shows an extensive involvement of almost the entire bone, with cartilage formation in the midportion of the diaphysis. (B) A magnification radiograph demonstrates morphologic details of fibrocartilaginous dysplasia


Complication of fibrous dysplasia. A 34-year-old man was noted to have a deformity of the left leg at age 5 years. Radiographic examination at that time showed typical involvement of the tibia by fibrous dysplasia, which subsequently was confirmed by biopsy. No treatment was given, and he was asymptomatic for 28 years until acute pain in his left leg developed. Conventional radiograph shows evidence of fibrous dysplasia affecting the proximal shaft of the tibia. A large osteolytic destructive lesion in the distal third of the tibia is also seen encroaching on the dense segment of bone and affecting the medullary portion and the cortex. There is a periosteal reaction and a soft-tissue mass. Biopsy revealed transformation of fibrous dysplasia to undifferentiated spindle-cell sarcoma. Dr. Emanuel R. Dantas


•  Distúrbios associados: o Sd. de Albright-McCunne: displasia fibrosa +

distúrbios endócrinos (desenvolvimento sexual prematuro, hiperparatireoidismo e outras endocrinopatias) + manchas café-com-leite.


Albright-McCune syndrome. Polyostotic fibrous dysplasia typically affects one side of the skeleton, as seen here in a 5-year-old girl with precocious puberty whose left upper and lower extremities were affected (Albright-McCune syndrome). Radiograph of the lower leg shows expansion of the tibia and fibula associated with thinning of the cortex. Note the ground-glass appearance of the medullary portion of these bones


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Tumores e lesões tumorais benignas - Parte 3