Eduardo Santini-Araujo

Osteosarcoma of the jaw: an analysis of a series of 74 cases

To analyse a series of cases of osteosarcoma of the jaw.

Giant Cell Reparative Granuloma

Giant cell reparative granuloma is a benign, reactive intraosseous process characterized by the presence of multinucleated giant cells, fibroblasts, and immature new bone formation in the absence of hyperparathyroidism. The lesion arises most commonly in the craniofacial skeleton and in small bones of the hands and feet. There is no sex predominance. Seventy-five percent of the lesions occur in the first three decades of life with a peak in the third decade. It is a solitary radiolucent expansive lesion located more frequently in the diaphysis or metaphysis – with evolution, it may extend to the epiphysis after growth plate closure. It presents a sharp margination. Histological features are as follows: Giant cells are commonly arranged in clusters. The giant cells are small and with few nuclei. Frequently, giant cells are seen around hemorrhagic zones. The stroma is formed by spindle mononuclear cells that produce collagen. Immature bone and osteoid reactive trabeculae lined by prominent osteoblasts are common features.

Metaphyseal Fibrous Defect

A benign nonneoplastic bone lesion, composed of fibrous tissue with a whorled pattern, with multinucleated giant cells, hemosiderin pigment and lipid-bearing histiocytes and inflammatory elements. It is one of the most frequent tumorlike lesions of bone and is more frequent in males (60 %) than in females (40 %). It has the highest incidence in the second decade (67 %) followed by the first decade (20 %), and it is most common in the lower metaphysis of the femur and the upper metaphysis of the tibia – both locations comprise 80 % of cases. The radiographic appearance is characteristic and usually diagnostic. It is a radiolucent, eccentrical, elongated lesion in the metaphysis of long bones, juxtaposed to the endosteal surface of one cortex. The long axis of the lesion is usually parallel to that of the host bone. Frequently, lesions can be confidently diagnosed based on radiographic features and puncture needle or surgical biopsy. Surgical treatment is not necessary and may be followed by X-rays.

Paget’s Disease of Bone and Sarcoma Complicating Paget’s Disease

Paget’s disease is a chronic disease of bone due to a hyperactivity of osteoclasts and osteoblasts resulting in abnormal bone remodeling. Lesions may be monostotic or polyostotic. It is most common in Northern European – Anglo-Saxon, New Zealanders, and Australians – people. It is more frequent in males than females, 2:1. It is more frequent after the fourth decade. The innominate bone and femur are the most common locations, followed by the lumbar spine, skull, and tibia. Radiologically, in the early stage, the lesion is sharply marginated, lytic, and radiolucent. In the skull it is called osteoporosis circumscripta. The transition between the lesion and the normal cortex is sharp and wedge shaped like a “blade of grass” or a “flame.” In the middle stage the roentgenologic appearance also changes, and radiolucency and radiodensity reflect the histopathological picture.

Bizarre Parosteal Osteochondromatous Proliferation

Osteofibrocartilaginous benign process arising in the surface of a bone, more common in hand and foot locations. There is no sex predominance and it is more common in the second and third decades. Near 75 % of cases are located on the surfaces of small bones of the hands and feet, more commonly in the proximal phalanges. Radiologically it is a he terotopic well-marginated calcified rounded mass attached to the cortical surface of the bone. The lesion presents three components: cartilage, bone, and spindle cells. Treatment consists of excision. Recurrence is seen in half of the patients. Malignant transformation is not reported.

“Brown Tumor” of Hyperparathyroidism

Localized destructive cyst-like areas in the skeleton, due to osteoclast resorption, in the general frame of primary, secondary, or tertiary hyperparathyroidism. It is more frequent in females and has the highest incidence between third and sixth decades. It is most common in tubular bones of the extremities and maxillary bones. The lesions may involve any skeletal bone and may be solitary or multiple. Radiologically, lesions are osteolytic with undefined margins. Histologically the bone marrow is replaced by a loose, richly vascularized, connective tissue. The remaining cancellous bone shows an increased osteoclastic activity on its surface. Hemorrhage and abundant hemosiderin pigment deposits are present. The most common differential diagnosis is a giant cell tumor of the bone. Surgical treatment in case of hyperfunctioning parathyroid – adenoma or hyperplastic glands – tends to reduce the osteoclastic activity.

Juxta-articular Bone Cyst

Juxta-articular bone cyst is an intraosseous, nonneoplastic, subchondral cystic lesion not related to joint pathology (especially osteoarthritis). The lesion contains mucoid fluid and is lined by fibrous tissue with myxoid change. If the joint presents osteoarthritis, the lesion is defined as a degenerative subchondral pseudocyst. The lesions have male predominance and most often occur in adults (80% between the third and sixth decades of life). They have a predilection for bones adjacent to the hip, knee, ankle, wrist, and shoulder joints. Roentgenograms show a well-outlined oval or round, osteolytic radiolucent lesion, frequently located eccentrically, in close relationship to the subchondral layer in the epiphysis of a long tubular bone. Histologically, the cyst is surrounded by a connective tissue membrane with scarce fibroblasts and parallel fascicles of collagen fibers; it lacks an evident synovial layer. Foci of myxoid transformation are present in the connective membrane; stellate cells and abundant mucoid substance are also seen. Painful cysts are treated with curettage and bone grafting.

Fibro-osseous Pseudotumor of Digits

Fibro-osseous pseudotumor of digits (FPD) is a rare benign lesion. It is a localized self-limited fibro-ossifying process that occurs in the proximal phalanx of digits. It is predominant in female. It occurs in adolescents or young adults, and the common sites of involvement are the proximal phalanx and metacarpal and metatarsal region. Radiologically, the lesion is an ill-defined and calcified soft tissue mass without zoning pattern of myositis ossificans. Histologically, the lesion resembles myositis ossificans. Treatment is excision of mature lesions which is curative.

Epidermoid Bone Cyst

Epidermoid bone cyst is an intramedullary, unilocular cyst lined by squamous epithelium containing keratin, with greater incidence in males. Acral lesions – common in manual workers – present from the third to sixth decade of life. Skull lesions are more frequent in the first decade. Excluding the epithelium-lined cyst of jaws, epidermoid cysts are located almost exclusively in the distal phalanges, followed by the skull – frontal and parietal region. Roentgenographically, it is a well-defined round osteolytic lesion. The inner lining of the cyst consists of squamous malpighian epithelium with a granulosa layer covered by laminated masses of keratin that fill the cavity. Treatment includes curettage or excision of the phalanx lesion or skull cysts.

Methods of Bone Biopsy

Biopsy must be done in every patient with a tumor in whom radical surgery or radio- or chemotherapy is contemplated. Close cooperation between surgeon, radiologist, oncologist, and pathologist is paramount to arrive at an accurate diagnosis and to avoid complications. The planning of the biopsy should be done after oncological principles and considering possible next surgical procedures in order to prevent local recurrences. Two types of biopsies may be done: open biopsy and needle biopsy, each method having advantages and disadvantages that should be considered in each case. With help of the modern image methods and with a team approach, it is possible to achieve a great degree of accuracy and safety in needle biopsy procedures.