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

ABSTRACT: 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.

Temporal Bone Chondroblastoma: Systematic Review of Clinical Features and Outcomes.

OBJECTIVE: Chondroblastoma is an uncommon benign neoplasm of cartilaginous origin usually involving the long bones. The temporal bone is a rare location for this tumor. The clinical profile, optimal medical and surgical management, and outcomes of treatment for temporal bone chondroblastoma remain unknown. METHODS: We performed a systematic review of the SCOPUS, PubMed, and CENTRAL databases for case reports and case series on patients with histopathologically proven temporal bone chondroblastoma. Data on demographics, clinical manifestation, surgical management, adjuvant treatment, and outcome on last follow-up were collected. RESULTS: A total of 100 cases were reported in the literature, including one described in the current study. The mean age of patients was 42.3 years (range, 2-85 years), with a slight male predilection (1.3:1). The most common clinical manifestations were otologic symptoms (e.g., hearing loss [65%], tinnitus, and otalgia) and a palpable mass. Surgical excision was performed in all cases, with gross total excision achieved in 58%. Radiation therapy was performed in 18% of cases, mostly as adjuvant treatment after subtotal excision. There were no deaths at a median follow-up of 2 years. Among the patients with detailed status on follow-up, 58% had complete neurologic recovery, 38% had partial recovery, and 4% had progression of symptoms as a result of tumor recurrence. CONCLUSIONS: Temporal bone chondroblastoma has a distinct clinical profile from chondroblastoma of long bones. Surgery is the mainstay of treatment, and radiation therapy may be given after subtotal excision. Outcomes are generally favorable after treatment.

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.

Clinical features, treatments and long-term follow-up outcomes of spinal chondroblastoma: report of 13 clinical cases in a single center.

PURPOSE: Chondroblastoma (CB) in the spine is extremely rare and there is little published information regarding this subject. We attempt to explore the clinical features of spinal CB and address the importance of total resection, especially total en bloc spondylectomy (TES) for the treatment of spinal CB. METHODS: Clinical data of 13 consecutive CB patients who received surgical treatment in our center between January 2006 and December 2016 were reviewed retrospectively. Recurrence-free survival (RFS) was estimated by Kaplan-Meier method and Log-rank test. RESULTS: The 13 CB patients included 9 men and 4 women with a mean age of 32 years. The lesions were located in the cervical spine in 2 cases, thoracic spine in 5 cases, and lumbar spine in 6 cases. All the patients were treated surgically using either curettage, piecemeal total resection, or TES. Postoperative radiotherapy was administered in 2 cases. The mean follow-up period was 41.6 months. Relapse occurred in 3 (23.1%) cases, resulting in one death in 60 months. The mean RFS duration was 28.7 months. CONCLUSIONS: CB predominantly affects males and various age groups. Spinal CB more commonly involves the thoracic and lumbar segments. Spinal CB usually appears as an aggressive and destructive bony lesion with a soft tissue mass on imaging, forming compression on the spinal cord in some cases. Recurrence is not uncommon for spinal CB. Total resection, especially TES, has been confirmed as a powerful method to control the disease, while curettage is more likely to associate with local recurrence. Radiotherapy does not seem to reduce local recurrence.

Cystic bone tumors of the foot and ankle.

Bone tumors are relatively rare in the foot and ankle region. Many of them present as cystic lesions on plain films. Due to the relative rarity of these lesions and the complex anatomy of the foot and ankle region, identification of such lesions is often delayed or they get misdiagnosed and mismanaged. This review discusses the most common cystic tumors of the foot and ankle including their radiographic features and principles of management.

Diagnostic value of histone 3 mutations in osteoclast-rich bone tumors.

Differentiating osteoclast-rich lesions of bone (giant cell tumor of bone [GCTB], chondroblastoma [CBA], and aneurysmal bone cyst [ABC]) can be challenging, especially in small biopsies or fine-needle aspirations. Mutations affecting codons 34 and 36 of either H3 Histone Family Member 3A (H3F3A) and/or 3B (H3F3B) are characteristically seen in GCTB and CBAs. We devised a simple assay to identify these mutations and evaluated its applicability for routine clinical diagnosis. One hundred twenty-four tissue specimens from 108 patients (43 GCTBs, 38 CBAs and 27 ABCs) were collected from the archives of the Calgary Laboratory Services/University of Calgary and Vanderbilt University Medical Center. Histology was reviewed by an expert orthopedic pathologist. A single base extension assay (SNaPshot) is used to interrogate each nucleotide in codons 34 and 36 of H3F3A and codon 36 of H3F3B. Final diagnoses were generated after re-reviewing cases and incorporating molecular findings. Of 43 GCTBs, 38 (88%) had an H3F3A G34W mutation; 35 of 38 CBAs (92%) had a K36M mutation in either H3F3B (N = 31; 82%) or H3F3A (N = 4; 11%); none of 27 ABCs had a tested mutation. Molecular findings changed the histomorphologic diagnosis in 5 cases (3 GCTB changed to ABC, and 2 ABC changed to GCTB). These findings support the diagnostic utility of mutational analysis for this differential diagnosis in certain challenging cases when clinicoradiologic and histomorphologic features are not definitive, particularly for distinguishing cellular ABC versus GCTB with secondary ABC.

Chondroblastoma in adult age.

PURPOSE: Chondroblastoma (CB) is a rare benign tumor that occurs most commonly in the second decade of life. No studies on CB in adulthood have been reported. Our purposes were to report a single-institution experience on CB in adults and to discuss the clinical and imaging findings, type of treatment, oncologic and functional outcomes. PATIENTS AND METHODS: All patients diagnosed and treated for CB from 1981 to 2014 were reviewed. The main inclusion criterion was patients above their 30 years of age at diagnosis. Clinical presentation, imaging, surgical treatment, complications and functional outcome were evaluated. Local recurrences were recorded. RESULTS: There were 15 males (65%) and 8 females (35%) with a mean age of 40 years (range 30-59 years). Tumor involved the small bones (talus, calcaneus, acromion, cuneiform, metatarsals) in 15 patients (65%) and the long bones in eight patients (35%). Treatment consisted of curettage only (6 cases), curettage plus phenol (13 cases), curettage plus radiotherapy (one patient with vertebral tumor), resection (two patients with CB of the acromion) and chopart amputation (one patient with a metatarsal tumor). At a mean follow-up of 8.4 years (range 3-30 years), twenty patients (87%) remained continuously disease-free, whereas three had local recurrences. None of the patients received chemotherapy. CONCLUSION: This study confirms that the occurrence and outcome of adult patients with CB are similar with those affecting younger patients. The main difference consists of the involved bones; flat bones and short tubular bones of the foot, especially the talus and calcaneus, are most commonly involved as opposed to long tubular bones. LEVEL OF EVIDENCE: Therapeutic study, level IV-1 (case series).

Calcaneal chondroblastoma with pathologic fracture and recurrence.

Chondroblastomas account for <2% of all bone tumors. The calcaneus is the fifth most common location of occurrence. Males in their second decade of life are most often affected, presenting with an insidious onset of localized pain, swelling, and tenderness. The finding of associated pathologic fracture has been rare. Imaging studies can aid in the formulation of the differential diagnosis and surgical plan. The definitive diagnosis requires histologic examination. Curettage and bone grafting is curative in >80% of cases. Local recurrence rates of ≤38% have been reported, most often because of inadequate resection, and have been associated with malignant conversion and metastasis. Adjuvant therapies can help minimize the incidence of local recurrence. Long-term follow-up examinations are recommended, given the protracted interval that can exist between recurrence and the potential for malignant conversion and metastasis. We present the case of a young, healthy, active male with a calcaneal chondroblastoma and associated pathologic fracture whose initial treatment consisted of curettage, hydrogen peroxide lavage, and allogeneic bone grafting. Recurrence developed at 15 months postoperatively and was treated with repeat curettage, high-speed burring, and reconstruction with steel Steinman pins and polymethylmethacrylate, resulting in no pain or recurrence at the 5-month follow-up point.

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]. / Nietypowa postac i lokalizacja chrzestniaka zarodkowego, nasladujacego przykostnego miesaka kosciopochodnego.

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]. / Knorpelbildende Knochentumore. Diagnose und Therapie.

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]. / Le chondroblastome et ses pièges diagnostiques.

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.