Avulsion fracture of the anterior inferior iliac spine with abundant reactive ossification in the soft tissue.

Patients who have sustained an avulsion fracture and present clinically during the healing phase of the injury may manifest a mass that clinically and radiographically mimics a malignant neoplasm. A 15-year-old male soccer goalkeeper presented with a large ossified mass in the soft tissues overlying the right hip 6 months after experiencing a popping sensation in his hip joint during a game. Although an osteosarcoma was suspected clinically and radiographically, a Tru-Cut needle biopsy of the lesion revealed reactive bone formation. Correlation of the clinical, radiographic, and pathologic findings indicated an avulsion fracture of the anterior inferior iliac spine with abundant reactive ossification in the soft tissues. The healing phase of an avulsion fracture may clinically and radiographically be mistaken for neoplasia. In such cases, a Tru-Cut needle biopsy may reveal the reactive nature of the process.

Fibrous dysplasia and cemento-ossifying fibroma. A histologic spectrum.

Fibrous dysplasia (FD) and cemento-ossifying fibroma (COF) are benign fibro-osseous lesions that are generally considered to be separate entities, distinguished by histologic and radiographic features. In our experience, some lesions lack the classic clinical, radiographic, or pathologic features of FD or COF and rather have overlapping features of both entities. Consequently, these cases are frequently diagnosed nonspecifically as fibro-osseous lesions. We examined 56 gnathic and extragnathic fibro-osseous lesions of bone morphologically, clinically, and radiographically to determine whether they can be reliably distinguished and whether their distinction has any clinical or prognostic significance. The lesions exhibited a broad morphologic spectrum of patterns ranging from pure FD (24 cases) to pure COF (10 cases). Twenty-two lesions contained a mixture of both patterns; 11 lesions with a predominant FD pattern contained calcified spherules histologically indistinguishable from those characteristically seen in COF. The remaining 11 lesions contained areas of typical FD adjacent to areas of COF. The lesions examined also demonstrated considerable radiographic overlap, and FD could not be reliably distinguished from COF. The recurrence rate was low for all lesions regardless of the histologic pattern. Because of histologic and radiographic overlap and similar low recurrence rate of FD and COF, we consider them to be related lesions, and COF is probably an opposing end of a morphologic spectrum of FD.

Giant solitary synovial chondromatosis.

The purpose of this report is to describe giant solitary synovial chondromatosis, a previously unrecognized feature of synovial chondromatosis that may histologically and radiographically mimic a malignant neoplasm. Giant solitary synovial chondroma is an intra- and/or extraarticular lesion measuring over 1 cm in size and sometimes as large as 20 cm. The radiographic appearance is that of a large, well-marginated mass either of irregular feathery calcification from coalescence of multiple small synovial chondromas, or a rounded calcified mass from the growth of a single synovial chondroma. Radiographically, giant solitary synovial chondromatosis may appear similar to chondrosarcoma and parosteal osteosarcoma.

Case report 806: Monostotic Paget's disease of the hand (fifth metacarpal).

Monostotic Paget's disease of bone is an uncommon disease, reported in the hand in only a few instances. We have described an additional case involving a metacarpal bone in a 43-year-old man. We believe this disease should be considered in the radiological differential diagnosis of lytic expansile, subchondral lesions of the hand.

Mesenchymal hamartoma of the chest wall in infants and children: a clinicopathological study of five patients.

Mesenchymal hamartoma of chest-wall is a rare benign lesion that has varied histological characteristics and usually occurs during early infancy. We report the histological characteristics of mesenchymal hamartoma found in five patients aged respectively 25 days, 5 months, 8 months, and 4 and 8 years at presentation. Two patients presented with respiratory distress, two with an asymptomatic chest-wall mass, and one with a deformity of the left chest wall. Surgical resection was performed on four patients and a biopsy only in one patient. Overall, the tumors were well delineated, lobulated, tan to reddish in color, and on section showed blood-filled cystic spaces with interspersed small islands of cartilage and fibrous tissue. Histological analyses demonstrated mixtures of bone trabeculae with spindle-cell stroma, chondroblast-like proliferation, mature and immature hyaline cartilage, and aneurysmal bone cyst formation. All patients are alive and well without evidence of disease. Despite the alarming clinical and histologic presentation, mesenchymal hamartoma of the chest wall is a non-neoplastic benign lesion.

Case report 798: Recurrent chondromyxoid fibroma in connective tissue of leg.

In summary, this is a case of recurrent CMF in soft tissue, 17 years after the diagnosis of the initial lesion. The literature concerning this entity is reviewed and the histological and radiological patterns are considered. The causative factors are evaluated and the prognosis is discussed.

Chondrosarcoma: MR imaging with pathologic correlation.

Magnetic resonance (MR) images of 21 surgically confirmed chondrosarcomas were retrospectively reviewed in conjunction with plain radiographs and computed tomographic scans and correlated with pathologic findings. The tumors appeared lobulated, and signal intensity, as analyzed visually (intermediate on T1-weighted, high on T2-weighted images), was similar for all lesions, regardless of pathologic type. Size of lesion was not an indicator of grade. The appearances of mesenchymal and dedifferentiated chondrosarcomas mimicked that of conventional chondrosarcoma. Extraskeletal chondrosarcoma was visualized as a lobulated soft-tissue mass. In all cases, MR imaging accurately depicted intraosseous and soft-tissue extent of tumor noted at surgery and pathologic examination. Histologic type or grade of chondrosarcoma generally cannot be characterized on the basis of visual analysis of signal intensity noted on routine MR images. However, MR imaging is excellent for exact delineation of tumor extent.

Imaging of the normal spine, developmental anomalies, and trauma of the spine and extremities.

Many significant papers in the current literature have considered the spectrum of developmental and traumatic alterations in the spine. The increasing role of MR and CT imaging is stressed as well as the continued importance of conventional radiography. The distinguishing features and pathology of developmental anomalies and traumatic injuries and the importance of accurate and complete diagnosis are discussed. This review includes articles that emphasize imaging of the normal spine, congenital anomalies, and trauma of the spine and extremities.

Easily missed trauma of bones and ligaments.

While most fractures and dislocations are easily detected by radiographic and physical examination, some traumatic events are overlooked because the normal radiographic anatomy is not appreciated. Furthermore, certain routine radiographic views are inadequate to detect specific injuries. "Chip" or "sprain" fractures are often considered minor injuries when they actually connote significant injury to ligaments and capsules. These injuries are usually dismissed by the primary care physician, who does not believe them serious enough to warrant consulting an orthopedic surgeon. However, some are also overlooked by radiologists and orthopedic surgeons. If these injuries are not treated adequately, permanent loss of function or death may result. With these thoughts in mind, we will describe some of these injuries and discuss the radiographic anatomy, the knowledge of which should preclude some of the serious mistakes of diagnosis.

Radiologic concepts of lymphoma of bone.

The imaging of lymphoma of bone is illustrated by conventional radiology, computed tomography, magnetic resonance imaging, and nuclear radiology. The features of non-Hodgkin's lymphoma are demonstrated.

Parosteal osteogenic sarcoma arising in cranial bones: clinical and radiologic features in eight patients.

Parosteal osteogenic sarcoma is a distinct surface bone tumor with a better prognosis than conventional osteogenic sarcoma. We studied eight histologically proved cases of cranial parosteal osteogenic sarcoma. The tumors were identical in histologic appearance to parosteal osteosarcoma arising in long bones. Clinically, the tumor presented as a hard, painless, nodular scalp mass. The prevalence in women outnumbered that in men by 3:1, with most cases occurring between the second and third decades of life. Plain radiographs showed a rounded, sessile bone growth of variable size arising from the outer table of the skull. The tumor was heavily ossified centrally with variable margins and, at times, with radiating bony spicules at the periphery. No satellite bone nodules were noted in adjacent soft tissues. In three cases a fine radiolucent cleft was demonstrated between the tumor and the underlying outer table on the tangential radiographs or CT. After en bloc resection of the tumor, follow-ups for 20 years in one patient and 1 year in two patients showed no recurrence. Parosteal osteosarcoma of the skull is a rare low-grade tumor that usually arises from the outer table of the skull and has distinctive radiologic features that should distinguish it from other exophytic cranial bone neoplasms.

Small cell osteosarcoma. A clinicopathologic study of 27 cases.

We report a study of 27 patients with small cell osteosarcoma (SCO), 17 from the M. D. Anderson Cancer Center (MDAH) and ten from the Pediatric Oncology Group (POG). There were 12 male patients and 15 female patients; 19 were white, five were black, and three were Hispanic. They ranged from 6 to 28 years of age with a median of 14 years. Histologically there were three patterns: Ewing's-like, lymphoma-like, and spindle cell. All cases showed osteoid formation and a few had chondroid areas. There was cytoplasmic glycogen in ten cases. Initial treatment for MDAH patients included intraarterial infusion of cisplatin in ten, amputation in four, partial mandibulectomies in two, and biopsy with local radiotherapy and systemic chemotherapy in one. All POG patients had resection or amputation followed by adjuvant chemotherapy. Twelve patients are alive, of whom nine have had significant follow-ups for 25 to 90 months. Fourteen patients are dead of lung, spine, and brain metastases from 1 to 23 months after initial diagnosis. One patient is alive with lung relapse at 4 months. In summary, SCO is a high-grade variant of osteosarcoma, with an incidence of up to 4% of all osteosarcomas, that affects patients of the same age group and has the same anatomic location as conventional osteosarcoma. Currently, SCO appears to have a prognosis that is the same as or slightly worse than that of conventional osteosarcoma. Furthermore, although intraarterial infusion is effective for the primary tumors in the bone, distant metastases are difficult to control.

Craniofacial osteosarcomas: plain film, CT, and MR findings in 46 cases.

Forty-six osteosarcomas of the cranial and facial bones were reviewed radiographically by using the conventional parameters for long bone tumors. There were 32 de novo osteosarcomas (11 maxillary, 13 mandibular, and eight cranial) and 14 postradiation osteosarcomas. All the maxillary tumors originated from the alveolar ridge, and the majority of mandibular lesions began in the body of the mandible. The postradiation osteosarcomas occurred in portions of bones at the borders of the radiation field; the latent period ranged from 4 years, 2 months to 50 years (mean, 14 years). The majority of de novo or postradiation craniofacial osteosarcomas were osteolytic with a long transition zone and no periosteal reaction; the exception was in the mandible, where nearly half the cases were osteoblastic and periosteal reaction was occasionally present. Tumor matrix mineralization occurred in more than 75% of the cases, and osteoid matrix calcification was most frequent, even though most tumors were chondroblastic. Soft-tissue extension of tumor was present in all cases and contained calcifications in more than half. Conventional radiographs are of limited value in evaluating head and neck osteosarcomas because of the superimposed bony structures. CT provides excellent detection of tumor calcification, cortical involvement, and, in most instances, soft-tissue and intramedullary extension. MR is even more effective in demonstrating the intramedullary and extraosseous tumor components on both T1- and T2-weighted images. However, CT and plain films are superior to MR in detecting the matrix calcifications and bone destruction or reaction.

Osteosarcoma chemotherapy effect: a prognostic factor.

Chemotherapy has become a routine part of the treatment of osteosarcoma. However, the precise role of preoperative chemotherapy remains in question. Between 1979 and 1982, a group of 40 patients were treated by multimodality therapy consisting of preoperative chemotherapy (intra-arterial cis-platinum and systemic adriamycin), surgery, and postoperative chemotherapy. Survival in this group is 64%, while continuous disease-free survival is 58%. Although age, sex, tumor size, site, and classification were found to be prognostic factors, histologic evidence of response to preoperative chemotherapy, measured as percent tumor necrosis, was found to be the most significant prognostic factor. When continuous disease-free survival was calculated as a function of tumor necrosis it was 91% in patients with greater than or equal to 90% tumor necrosis, while it was 14% in patients with less than 90% tumor necrosis. At initial presentation, 7% of patients were judged limb-salvage candidates. But due to the local effects of preoperative chemotherapy, 60% ultimately underwent limb-salvage surgery. Preoperative arteriograms were a reliable means of monitoring response to chemotherapy and served as an indicator of residual viable tumor. Using arteriogram directed planes of section, postchemotherapy, specimens were "mapped" and analyzed for chemotherapy effect. When present, residual viable tumor was preferentially found at the interface of tumor and normal anatomic structures; "sanctuary sites." It is necessary that standard methods for analyzing postchemotherapy specimens be developed; a technique is described.