Prognostic factors of chondroblastic osteosarcoma and nomogram development for prediction: A population-based, STROBE-compliant study

The present study aimed to develop nomograms to predict survival in patients with chondroblastic osteosarcoma (COS).An analysis was conducted of 320 cases of COS collected from the surveillance, epidemiology, and end results (SEER) database between 2004 and 2015. Independent prognostic factors were screened using univariate and multivariate Cox analyses. Subsequently, nomograms were established to predict the patients' cancer-specific survival (CSS) and overall survival (OS) rates. The prediction accuracy and discriminative ability of the nomograms were examined using calibration curves and the concordance index (C-index).As revealed in the univariate and multivariate Cox regression analysis, age, tumor size, the primary site, the presence of metastasis, a history of having undergone surgery, and a history of having received radiotherapy were found to be independent prognostic factors associated with survival in patients with COS (all P < .05). Furthermore, age >39 years, the presence of distant metastasis, no history of having undergone any surgery, and tumor size >103 mm were found to be associated with poor prognosis in patients, while the primary site of the mandible and no history of having undergone radiotherapy showed associations with a more favorable prognosis in patients. Next, nomograms were constructed to predict the OS and CSS in patients with COS.We constructed nomograms that can provide accurate survival predictions in patients with chondroblastic osteosarcoma. These nomograms can help surgeons customize the treatment strategies for patients with chondroblastic osteosarcoma.

Calcaneal Bone Tumors

Bone tumors of the foot are an uncommon finding. Most tumors are found incidentally on imaging and are benign. Care must be taken although due to the aggressive nature of malignant bone tumors that can occur in the calcaneus. Malignant lesions will more commonly present with symptoms of pain and swelling. Often misdiagnosed as soft tissue injuries, it is critical to be able to diagnose and treat these lesions early. Imaging plays an important role with plain films and advanced imaging. Surgical treatments can range from curettage with grafting to amputation for more aggressive lesions.

Percutaneous Cryotherapy for Treatment of Chondroblastoma: Early Experience

Surgical curettage is currently the standard of care for the chondroblastoma, but in peri-articular tumors it is limited by its morbidity. In this preliminary report, we evaluate the feasibility of percutaneous cryotherapy as an alternative ablative treatment for chondroblastoma. Three patients with a chondroblastoma treated by CT scan-guided cryotherapy are presented in this article. Pain permanently disappeared 2 days after the procedure. No local tumor recurrence or cartilage damage was observed by MRI performed 1 year after the intervention. This preliminary case report suggests that percutaneous cryotherapy may be a possible alternative to the current standard of care in chondroblastoma. Further studies are needed to evaluate if this technique offers similar anti-tumoral efficacy while providing better pain relief and less morbidity than curettage.

Chondroblastoma: a rare cause of femoral neck fracture in a teenager

Chondroblastomas usually present in the epiphyseal region of bones in skeletally immature patients. These uncommon, benign tumors are usually treated with curettage and use of a bone-void filler. Here we report a case of a hip fracture secondary to an underlying chondroblastoma in a 19-year-old woman. Open biopsy with intraoperative frozen section pointed toward a diagnosis of chondroblastoma. Extended curettage was performed, followed by cryotherapy with a liquid nitrogen gun and filling of the defect with calcium phosphate bone substitute. The femoral neck fracture was stabilized with a sliding hip screw construct. The patient progressed well and continued to regain functional status. A final pathology report confirmed the lesion to be a chondroblastoma. Clinicians should have heightened awareness of a pathologic lesion in a young person presenting with a femoral neck fracture and should consider the uncommon differential diagnosis that the lesion is located in the greater trochanter apophysis.

[An aggressive chondroblastoma mimicking paraosteal osteosarcoma]

We present a rare case of an aggressive form of chondroblastoma arising from proximal radius. Because of an initial histopathologic diagnosis of paraosteal osteosarcoma, the patient was treated with preoperative chemotherapy and afterwards a local tumor resection with one half of proximal radius was performed. A final histopathologic examination revealed typical benign chondroblastoma. We discuss the rare localisation of chondroblastoma and its differential diagnosis with surface osteosarcoma.

[Chondroblastoma]

Chondroblastom, benign cartilage tissue neoplasm, accounts for 1% of all bone tumors. It is encountered in any skeletal bones mainly in persons aged 10 and 25 years. Morphologically, it is represented as large homogenous cells--well-defined oval polygonal chondroblasts with a fine eosinophilic cytoplasm, and a round-to-oval nucleus. Cartilaginous portions of chondroblastoma form lobular structures. The tumor always comprises single-to-multiple multinucleate giant cells. The pathognomonic sign of chondroblastoma is intercellular reticular basophilically stained calcifications as a mesh. Mitotic cells, rather than abnormal ones, are present. There are cases of primary malignant chondroblastomas.

[Cartilage tumours of the bone. Diagnosis and therapy]

Primary malignant bone tumours are rare. The annual incidence of these tumours is 10 per 1 million. Nearly 30% of the primary malignant bone tumours are malignant cartilage tumours. The frequency of benign cartilage tumours cannot be definitely estimated because these tumours are normally clinically inapparent and therefore often diagnosed as an incidental finding. The cartilage tumours appear as benign lesions (e.g. chondroma), as borderline tumours (proliferative chondroma vs grade I chondrosarcoma) or as highly malignant chondrosarcoma (e.g. dedifferentiated chondrosarcoma). Commensurate with the different clinical and oncological manifestations of the cartilage tumours, there are wide differences in the treatment and clinical course of the individual tumour. This article discusses the problems in the diagnosis and treatment of cartilage tumours from an orthopaedic point of view.

[Review of thirty patients with bone chondroblastoma]

BACKGROUND/AIM

To analyse the results of the treatment of the patients with the diagnosis of chondroblastoma, to confirm the possible malignancy and to recommend the best and the safest method of the treatment.

METHODS

We reviewed the cases of 30 patients with chondroblastoma who were treated between 1975 and 2004. Data were obtained using complete medical documentation, physical examinations, radiographic findings, and the available additional diagnostic procedures.

RESULTS

We found that the proximal part of the tibia, proximal part of the humerus, and distal part of the femur were the most common sites of the tumor in 63% of the cases. The higher prevalence of chondroblastoma in male patients was found, especially in the second decade of life. The patients were treated with different surgical procedures after histologically confirmed chondroblastoma. In 1 of the patients, radiation therapy was performed because the lesion recurred, after which the malignant transformation of chondroblastoma occured. We found two more malignant chondroblastomas, one of which had been diagnosed as a primary tumor. Seven patients had a local recurrence, one of them had a second recurrence and the malignant transformation of chondroblastoma. The only solution was a below-knee amputation.

CONCLUSION

Chondroblastoma of bone is a rare lesion with the high local recurrence rate. We emphasized the need for an adequate and rapid diagnosis, including histological verification. The treatment was strictly surgical. The basic goal of the treatment was to avoid tumor penetration into articular cavity and/or local soft tissues. Malignant chondroblastoma of bone should be treated with radical surgical resection, avoiding any adjuvant therapy.

Genetics of chondrosarcoma and related tumors

PURPOSE OF REVIEW

The burgeoning body of information on the genetic changes present in and underlying the development and biology of human cancers has carried implications regarding the possible genetic events that are responsible for not only the genesis of these cancers but also the hope of the cure for these cancers. Chondrosarcomas are a group of tumors that fall into this category. The purpose of this review is to summarize the genetic findings in these tumors.

RECENT FINDINGS

The histopathologic variability of chondrosarcomas is reflected in the complexity and lack of specificity of their cytogenetic and molecular genetic findings, except for extraskeletal myxoid chondrosarcomas. These are characterized in the preponderant number of cases by a translocation, t(9;22)(q22;q12), and in a small number of cases by variant translocations t(9;17)(q22;q11) and t(9;15)(q22;q21). These translocations lead to the formation of abnormal fusion genes and gene products (proteins). In each of these translocations, the CHN gene is involved, resulting in the chimeric fusion genes EWS/CHN, RBP56/CHN, and TCF12/CHN, respectively. The specific translocations and their associated molecular genetic changes are diagnostic of extraskeletal myxoid chondrosarcomas. The abnormal proteins resulting from these fusion genes aberrantly affect gene transcription and cellular signaling pathways thought to be responsible for initiating sarcoma formation. In skeletal (central) chondrosarcomas of varying histopathologic types, the cytogenetic and molecular genetic findings are variable, complex, and apparently lacking in specificity. These changes may reflect a stepwise process (or processes) of oncogenesis involving an array of genes.

SUMMARY

Although some cartilaginous tumors are characterized by specific or recurrent chromosome alterations and molecular genetic changes, much is yet to be learned about the nature and sequence of these genetics events and about their unique role in the stepwise process involved in the development and biology of each tumor type, both malignant and nonmalignant. Until such time, some of the genetic changes, particularly the presence of specific translocations, can be of definite diagnostic value.

[Chondroblastoma and its differential diagnosis]

Chondroblastoma is one of the most well defined cartilaginous tumors of bone on imaging and pathological findings. However in practice, the pathologist is faced with diagnostic difficulties. The most recent features of the tumor are developed in the review: clinical findings, skeletal distribution, and above all, the results of the imaging study which has to be strictly correlated with histology for the diagnosis as well as for the differential diagnosis, location, osteolysis, matrix production, periosteal reactions, MRI studies. Histopathology of chondroblastoma is described: cellular component, architecture, and secondary changes. Usefulness of cytopathology is also stressed on smears or tumor imprints. Main findings of recent and various immunohistochemical stains are described and discussed as well. Ultrastructural and cytogenetic studies are summarized. Treatment, natural history, and prognosis of the tumor are developed. The three most important differential diagnoses are giant cell tumors, clear cell chondrosarcomas, and aneurysmal bone cysts.

Myxoid chondrosarcoma of the sphenoid sinus and chondromyxoid fibroma of the iliac bone: cytomorphologic findings of two distinct and uncommon myxoid lesions

Myxoid chondrosarcoma (MCS) and chondromyxoid fibroma (CMF) are two uncommon myxoid cartilaginous neoplasms with distinct cytologic features, histologic patterns, and immunoprofiles. Because these neoplasms have characteristic biological behaviors and management, their correct diagnosis is crucial to avoid debilitating and unnecessary surgical procedures. We report the imprint cytology (IC) preparation findings along with the differential diagnosis in one case each of myxoid chondrosarcoma and chondromyxoid fibroma of the splenoid sinus and iliac bone, respectively. The two great mimickers for these neoplasms, chordoma and chondrosarcoma, represent difficult diagnostic challenges, especially when MCS and CMF occur in unusual locations. IC in conjunction with the clinical and radiologic findings can provide a rapid preliminary intraoperative diagnostic interpretation which can aid in planning the immediate surgical management, as well as guide specific tissue triage for key ancillary studies such as electron microscopy and cytogenetic analyses. To the best of our knowledge, there have been no cytologic reports of MCS of the sphenoid sinus and CMF of the iliac bone.

Malignant chondroblastoma presenting as a recurrent pelvic tumor with DNA aneuploidy and p53 mutation as supportive evidence of malignancy

We report a rare case of malignant chondroblastoma, which presented in a 47-year-old man as a recurrent tumor, 18 years following wide excision of a typical pelvic chondroblastoma. Radiologic studies of the recurrent tumor showed a large, lytic, destructive lesion of the right pelvic bones and femur, with a pathologic fracture of the latter, a large pelvic soft tissue mass, and multiple pulmonary metastases. Biopsy tissue showed typical features of chondroblastoma, but also increased nuclear atypia, hyperchromasia, and pleomorphism, compared to the original tumor, and, most significantly, abnormal mitotic figures. Immunohistochemical studies of the recurrent tumor revealed p53 mutation and extensive proliferative activity, and flow cytometric studies showed DNA aneuploidy, none of which was present in the original tumor. The patient received chemotherapy and radiation, but died of disease eight months after presentation. We also review chondroblastoma in general, to assign this unusual lesion to a tumor subtype.

Chondroblastoma of the temporal bone: a clinicopathologic study of five cases

Chondroblastoma is a rare benign bone tumor. It commonly affects the epiphysis of long bones during the second and third decades of life. Chondroblastoma of the temporal bone is extremely rare. We reviewed five cases of chondroblastoma arising in the temporal bone. Four cases were female and one was male. The ages ranged from 41 to 60 years (mean, 53.6 years). All cases involved the temporal bone. Three involved the left side and two the right. Chief complaints were long-standing localized pain and hearing difficulty. A sharply demarcated lobulated mass was the main radiological finding. Microscopic findings were those of chondroblastoma of usual locations. Two cases showed aneurysmal bone cyst-like areas. Immunohistochemical studies for CD34, CD99, S-100 protein and cytokeratin were performed. Tumor cells were diffusely positive for S-100 protein in three cases and weakly positive for cytokeratin in one case. CD34 and CD99 were negative in all cases. In summary, chondroblastoma of the temporal bone is rare and occurs in older age group than reported cases of chondroblastoma of the usual location in the literature.

Chondroblastoma during the growing age

Chondroblastoma is a benign tumor of bone with a relatively high incidence in older children and adolescents. The regions of the shoulder, hip, and knee are mainly affected, with preference for the epiphysis. Treatment currently consists of excochleation, bone grafts, and sometimes adjuvant therapy such as phenol cauterization or cryosurgery. Because the tumor often is localized near a joint or growth plate, functional impairment and growth disturbances could be expected. Recurrences also are a major concern. A brief overview is given, as well as a presentation of 116 cases in the growing age group from the material of the Dutch Bone Tumor Committee. It seems justified to conclude that most lesions will heal with proper excochleation and bone graft, but there is a reasonable chance of recurrence. Loss of function as well as growth disturbances were not commonly seen in our series. One case of metastasis was found.

Ring chromosome 4 as the sole cytogenetic anomaly in a chondroblastoma: a case report and review of the literature

Chromosome analysis of a chondroblastoma of the right distal femur in a 31-year-old male patient revealed a ring chromosome 4 in approximately one-third of the analyzed cells. The remaining cells had a normal karyotype. These findings were subsequently confirmed by fluorescence in situ hybridization (FISH) with a chromosome-4-specific library. FISH with cosmids pC847.351 (4p16.3) and cT171 (4q35) revealed that fewer than 300 kilobase pairs (kbp) are deleted. To our knowledge, ring chromosome 4 has never been reported in this type of neoplasm. There are, however, several reports of chondroblastoma with other chromosome abnormalities, but the relation of these anomalies to this tumor specifically is unclear. In this report, we also provide a review of the literature concerning cytogenetic studies in chondroblastoma. The possible significance of ring chromosome 4 in this type of tumor is discussed.

Chondromyxoid fibroma of bone: a clinicopathologic review of 278 cases

In a study of the clinical, radiographic, and pathological features of chondromyxoid fibroma, the tumor was slightly more common in men, usually in the second decade of life. Almost half of the tumors involved the long bones, although the ilium and the small bones were also common sites. Roentgenograms showed a sharply marginated, lobulated, lucent defect in the metaphysis. The tumor involved the medullary bone in an eccentric fashion, and the cortex was thinned and expanded. Periosteal reaction and soft tissue extension were uncommon. Mineralization was identified in 13% of the lesions. Histologically, the tumors were almost always arranged in lobules, which were prominent (macrolobular) or somewhat indistinct (microlobular). The tumor cells were spindle-shaped or stellate and arranged in a myxoid matrix. Calcification was seen in more than one third of the cases but was rarely prominent. Hyaline cartilage and chondroblastoma-like areas were not uncommon. Approximately 18% of tumors showed bizarre nuclei. Permeation of bony trabeculae was uncommon. Treatment was conservative surgical removal; approximately one fourth of the patients had recurrence.

Surgery for locally aggressive bone tumours

Treatment of 16 patients with aggressive benign bone tumours and one patient with a low grade malignancy with a combined regimen of cryosurgery, phenolization and acrylic cementation is reported. Patients were aged between 9 and 51 years and were treated by this method between the years 1986 and 1993. Minimal follow up was 13 months. The commonest histological diagnosis was giant cell tumour (7), followed by aneurysmal bone cyst (6), chondromyxoidfibroma (3) and low grade chondrosarcoma (1). Patients were assessed for functional outcome and local recurrence. On average 86 per cent of premorbid function was restored at follow up and there was one local recurrence (6.29 per cent). We conclude that this is a satisfactory method of gaining local control of these tumours.

[Surgical procedures for bone neoplasms in children]

The treatment of 40 patients with bone tumors have been presented. The primary tumors were located in the following sites: femur (14), tibia (8), fibula (4), humerus (4), scapula (1), clavicle (2), pelvis (5), hand (1). Investigated group were: osteosarcoma (18), Ewing's sarcoma (14), chondrosarcoma (2), fibrosarcoma (1), synovial sarcoma (1), chondroblastoma (4). In the most frequent malignant bone tumors, osteosarcoma and Ewing's sarcoma, unified management was adapted. The treatment was initiated with multidrug chemotherapy and followed by surgery or radiotherapy (Ewing's sarcoma) of the primary site. Surgery was performed in 30 cases: 19 mutilating operations because of the broad local invasion, 11 conservative surgical procedures (limb -- salvage operations). Satisfactory oncological and functional effect can be achieved after limb-salvage surgical procedures in the cases of localized, especially semimalignant bone tumors.

Phenol as an adjuvant in the control of local recurrence of benign neoplasms of bone treated by curettage

Throughout the present century phenol has been used to "sterilise" the edges of cavities left in bone after the clearance of benign tumours in order to reduce the risk of local recurrence. The results have been analysed of 165 benign bone tumours capable of local recurrence (aneurysmal bone cyst, chondroblastoma, giant cell tumour) treated with and without the use of phenol. The overall recurrence rate was 41% in 98 cases treated by simple curettage and 7% in 27 cases treated by curettage followed by the application of phenol.

Chondroblastoma: a clinical and radiological study of 104 cases

The clinical and radiographic findings in 104 patients with chondroblastoma are presented. Pain was an almost constant presenting complaint, often accompanied in the case of para-articular lesions by impaired function of an adjacent joint. The majority (80%) were in long bones with a mean age of presentation of 16 years. The characteristic radiological image of these lesions was an eccentric radiolucency, having a sharply defined sclerotic margin and containing areas of calcification in approximately a third of cases. They were always related to a growth plate. Nearly half were confined to the affected epiphysis or apophysis itself, but most of the remainder had traversed the growth plate to involve also the adjacent metaphysis. The bones around the knee and the proximal ends of the humerus and femur were the sites of predilection. A minority (20%) affected flat bones and short tubular bones of the hand and foot, with a peculiar affinity for the calcaneus and talus. The mean age of presentation of these was 28 years. The radiological pattern was similar, except for a greater tendency to expand the affected bone. Complications included the formation of a secondary aneurysmal bone cyst in 16 cases (10 of them in long bones), one malignant chondroblastoma, and one fibrosarcoma developing after radiation of the original chondroblastoma.

Metastatic chondroblastoma. Report of a fatal case with a review of the literature on atypical, aggressive, and malignant chondroblastoma

A boy with metastatic and fatal chondroblastoma is presented. Unlike previously published examples of metastatic chondroblastoma, these metastases developed before any operative manipulation of the primary tumor. The histologic characteristics of the primary, metastatic, and locally recurrent tumors were those of a conventional chondroblastoma. A review of published cases of atypical, aggressive, and malignant chondroblastoma is presented with current follow-up information. Although some metastatic chondroblastomas may result from operative manipulation of the primary tumor and are clinically benign, other histologically benign chondroblastomas exist that are capable of pursuing a malignant course. The authors designate these as malignant chondroblastomas. No histologic criteria exist for the separation of these tumors.