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Rationale: Pulmonary blastoma is an extremely rare and highly aggressive tumor. Only a few hundred cases of pulmonary blastoma have been reported. In other cases, a definitive diagnosis is often made through surgical resection. The use of preoperative histopathological sampling in diagnosing was of limited value because of the variety of pulmonary blastoma histology. And there was no literature that the first biopsy was attempted with medical thoracoscopy for diagnosis., Patient Concerns: A 65-year-old man presented to our hospital with pleural effusion and lung mass., Diagnoses: The patient was initially diagnosed with dedifferentiated chondrosarcoma by medical thoracoscopic biopsy but the final diagnosis was pulmonary blastoma through bilobectomy., Interventions: Medical thoracoscopy, and video-assisted thoracoscopic surgery (bilobectomy) followed by adjuvant chemotherapy., Outcomes: After surgical resection of the tumor, adjuvant chemotherapy has been performed 5 cycles at 3 weeks intervals, and there was no evidence of recurrence on follow-up computed tomography performed 4 months after surgery., Lessons: Medical thoracoscopy is useful for the diagnosis of indeterminate pleural effusion; however, caution is needed when confirming rare malignancies, such as pulmonary blastoma. Although surgical resection is the treatment of choice, appropriate adjuvant chemotherapy to improve the prognosis may be necessary if there is pleural metastasis., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Competing Interests: The authors declare no conflicts of interest.

Abstract: A 24-year-old man presented with a 2-month history of progressive, painless vision loss in the right eye, with no history of headache, nasal congestion, rhinorrhea, or epistaxis. His visual acuity was counting fingers at 1 ft in the right eye and 20 of 20 in the left eye with a right relative afferent pupillary defect and mild temporal optic disc pallor. MRI of the brain and orbits showed a mass involving bilateral ethmoid and sphenoid sinuses and right nasal cavity. He underwent urgent extended endoscopic endonasal transsphenoidal approach for resection of the sinonasal skull base tumor and photon radiation therapy. Pathology revealed a well-differentiated cartilaginous neoplasm with focal areas of entrapped native bone, consistent with a chondrosarcoma WHO grade I/III. At 6-month follow-up after surgery, he had a visual acuity of 20/40 in the right eye and 20/20 in the left eye. Malignant tumors from the sinonasal area should be kept in the differential diagnosis for compressive optic neuropathies and may present with vision loss even in the absence of nasal or sinus symptoms., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 by North American Neuro-Ophthalmology Society.)

Study Design: Retrospective analysis., Objective: The aim of this study was to develop and validate a competing-risk-based prognostic model and a nomogram for predicting the three- and five-year probability of cancer-specific death (CSD) in patients with spinal and pelvic chondrosarcoma., Summary of Background Data: The issue of competing risk has rarely been addressed and discussed in survival analysis of bone sarcoma. In addition, the Fine and Gray model, a more accurate method for survival analysis in the context of competing risk, has also been less reported in prognostic study of chondrosarcoma., Methods: A total of 623 patients with spinal or pelvic chondrosarcoma were identified from the SEER database and were divided into a training and a validation cohort. These two cohorts were used to develop and validate a prognostic model to predict the 3- and 5-year probability of CSD, considering non-CSD as competing risk. The C-index, calibration plot, and decision curve analysis were used to assess the predictive performance and clinical utility of the model., Results: Older age (subdistribution hazards ratio [SHR]: 1.02, 95% confidence interval [CI]: 1.01∼1.03; P = 0.013), high grade (SHR: 2.68, 95% CI: 1.80∼3.99; P < 0.001), regional involvement (SHR: 1.66, 95% CI: 1.06∼2.58; P = 0.026), distant metastasis (SHR: 5.18, 95% CI: 3.11∼8.62; P < 0.001) and radical resection (SHR: 0.38, 95% CI: 0.24∼0.60; P < 0.001) were significantly associated with the incidence of CSD. These factors were used to build a competing-risk-based model and a nomogram to predict CSD. The C-index, calibration plot, and decision curve analysis indicated that the nomogram performs well in predicting CSD and is suitable for clinical use., Conclusion: A competing-risk based prognostic model is developed to predict the probability of CSD of patients with spinal and pelvic chondrosarcoma. This nomogram performs well and is suitable for clinical use.Level of Evidence: 4., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Undifferentiated/dedifferentiated carcinoma is an aggressive endometrial carcinoma which remains underrecognized but may account for up to 9% of all endometrial malignancies. We describe 3 cases in which the undifferentiated component was associated with sarcomatous differentiation, characterized by spindled cells in 2 cases and heterologous malignant cartilage in 1 case. Two of the 3 cases demonstrated mismatch repair deficiency by immunohistochemistry. This phenomenon has not previously been formally reported and increases the likelihood of misdiagnosis, especially within biopsy samples; differential diagnoses may include endometrial stromal sarcoma and grade 3 endometrioid adenocarcinoma with spindled morphology. We review the current literature and provide strategies for resolving the differential diagnoses, with a suggested panel of antibodies which includes EMA, E-cadherin, and mismatch repair proteins as approximately 50% of cases show loss of mismatch repair expression.

Rationale: Chondrosarcoma of the sacrum is a highly unusual disease without standard curative managements yet. The objective of this study is to report a very rare case of chondrosarcoma of the sacrum successfully operated by percutaneous vertebroplasty. The management of these unique cases has yet to be well-documented., Patient Concerns: A 45-year-old woman presented with a five-month history of continuous and progressive pain and numbness of left extremity. A lytic, expanding lesion of the sacrum and paraspinal region with severe epidural spinal cord compression was identified., Diagnosis: MRI of spine showed spinal cord compression secondary to the epidural componant of the giant mass, with increased marrow infiltration of the left S2 vertebral and paravertebral region, which presented as a solid tumor. Post-operative pathology confirmed the diagnosis of sacral well-differentiated chondrosarcoma (stage I B)., Interventions: The patient underwent percutaneous vertebroplasty and cement augmentation of sacrum via a posterior approach., Outcomes: The patient's neurological deficits improved significantly after the surgery, but the patient died of multiple systemic metastases at the 2-year follow-up visit. There were no complications associated with the operation during the follow-up period., Lessons: Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Combined efforts of specialists from orthopedics, radiology, neurosurgery, pathology, and medical oncology led to the successful diagnosis and management of this patient. Giant sacral chondrosarcoma, although rare, should be part of the differential diagnosis when the patient presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the sacral chondrosarcoma when the tumor has caused neurological deficits or other severe symptoms. Osteoplasty by cement augmentation is also a good choice for surgical treatment.

Rationale: Chondrosarcoma is a malignant mesenchymal tumor originating from cartilage. The pelvis, ribs, femur, and humerus are the most frequently affected sites, and scapula involvement is relatively rare. The aim of the present study was to report a case of chondrosarcoma in the scapula., Patient Concerns: A 42-year-old woman presented with a 3-month history of a painful mass in the right scapula., Diagnoses and Intervention: The patient underwent tumor resection. The post-operative pathological diagnosis was scapula chondrosarcoma., Outcomes: Following resection, the patient continued to receive routine follow-up care. There was no recurrence or tumor metastasis at a follow-up of 5 years., Conclusions: Surgery remains the primary therapy for chondrosarcoma. One of the greatest challenges in the management of chondrosarcoma is to accurately assess tumor grade before surgical intervention. Chemotherapy and radiotherapy have been applied without success. Chemo- and radioresistance have been examined beyond classic phenotypic properties to identify more efficient therapeutic strategies. Therefore, development of future novel therapies is contingent upon elucidating the molecular mechanisms of chondrosarcoma.

Rationale: Extraskeletal myxoid chondrosarcoma is a slow-growing soft tissue tumor of adults with a propensity for local recurrence and eventual metastasis. Only 17 pediatric and adolescent cases have been reported., Patient Concerns: Here we present an 11-year-old boy with a 3-year history of a slowly growing painless left leg mass. Magnetic resonance imaging of the lesion revealed a subfascial well-circumscribed lesion with intramuscular extension in the medial gastrocnemius muscle of the left leg., Diagnoses: He underwent wide local excision of the mass and the histomorphological and immunohistochemical findings were consistent with extraskeletal myxoid chondrosarcoma., Interventions: Possible radiotherapy was the further management plan., Outcomes: He was in good condition with no evidence of recurrence at 6 months postsurgery., Lessons: Although pediatric cases of extraskeletal myxoid chondrosarcoma were reported to be aggressive, the tumor in this case demonstrated indolent behavior. Furthermore, the tumor in this case showed primitive round cell foci which adds to a previous study that especially reported this morphology in pediatric cases.

Rationale: Intracranial chondrosarcomas are rare entities and most of which arise off the midline. Chondrosarcomas that occur in the sellar region are extremely rare, and to the best of our knowledge, there is no reporting about sellar chondrosarcoma with amenorrhea as the onset symptom., Patient Concerns: A 45-year-old woman presented with a 7-month history of amenorrhea and a 3-month history of progressive visual loss in the left eye., Diagnosis: The patient was diagnosed with recurrent sellar chondrosarcoma arising from intrasellar with extensive tumor invasion into bilateral sphenoid sinuses., Interventions: Twice endonasal transsphenoidal tumorectomies were performed followed with a stereotactic radiotherapy and hormone replacement therapy., Outcomes: The patient's condition was stable and her visual symptoms improved, the hormones returned to normal, and no recurrence was noted on MRI after six months., Lessons: Sellar chondrosarcomas with the onset of endocrine dysfunctions are extremely rare, which may be misdiagnosed as pituitary adenoma and the definitive diagnosis depends on histopathological and immunohistochemical evidence. The first choice of treatment is surgery with the goal of complete resection, and postoperative adjuvant radiotherapy should be highlighted.

Study Design: Retrospective analysis., Objective: To determine the epidemiology and prognostic indicators in patients with chondrosarcoma of the osseous spine., Summary of Background Data: Chondrosarcoma of the spine is rare, with limited data on its epidemiology, clinicopathologic features, and treatment outcomes. Therapy centers on complete en bloc resection with radiotherapy reserved for subtotal resection or advanced disease., Methods: The Surveillance, Epidemiology, and End Results Registry was queried for patients with chondrosarcoma of the osseous spine from 1973 to 2012. Study variables included age, sex, race, year of diagnosis, size, grade, extent of disease, and treatment modality., Results: The search identified 973 cases of spinal chondrosarcoma. Mean age at diagnosis was 51.6 years, and 627% of patients were males. Surgical resection and radiotherapy were performed in 75.2% and 21.3% of cases, respectively. Kaplan-Meier analysis demonstrated overall survival (OS) and disease-specific survival (DSS) of 53% and 64%, respectively, at 5 years. Multivariate Cox regression analysis showed that age (OS, P < 0.001; DSS, P = 0.007), grade (OS, P < 0.001; DSS, P < 0.001), surgical resection (OS, P < 0.001; DSS, P < 0.001), and extent of disease (OS, P < 0.001; DSS, P < 0.001) were independent survival determinants; tumor size was an independent predictor of OS (P = 0.006). For confined disease, age (P = 0.013), decade of diagnosis (P = 0.023), and surgery (P = 0.017) were independent determinants of OS. For locally invasive disease, grade (OS, P < 0.001; DSS, P = 0.003), surgery (OS, P = 0.013; DSS, P = 0.046), and size (OS, P = 0.001, DSS, P = 0.002) were independent determinants of OS and DSS. Radiotherapy was an independent indicator of worse OS for both confined (P = 0.004) and locally invasive disease (P = 0.002). For metastatic disease, grade (OS, P = 0.021; DSS, P = 0.012) and surgery (OS, P = 0.007; DSS, P = 0.004) were survival determinants for both OS and DSS, whereas radiotherapy predicted improved OS (P = 0.039)., Conclusion: Surgical resection confers survival benefit in patients with chondrosarcoma of the spine independent of extent of disease. Radiotherapy improves survival in patients with metastatic disease and worsens outcomes in patients with confined and locally invasive disease., Level of Evidence: 4.

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue sarcoma usually presenting in proximal extremities of middle-aged men. The authors discuss a unique case of EMC, localized in the plantar foot of a 76-year-old woman, clinically suspected as plantar fibromatosis. It is important to avoid misdiagnosis of EMC because of their propensity for late recurrence and their metastatic potential.

Chondrosarcoma of the larynx is a rare tumor, accounting for 0.07% to 2% of all laryngeal cancers. Nevertheless, it represents the most frequent nonepithelial neoplasm of the laryngeal region.Laryngeal chondrosarcomas are usually characterized by slow growth and low metastatic potential.The exact etiopathogenesis of chondrosarcoma is still debated. Diagnosis can be difficult given the slow rate of growth and nonspecific patient symptoms at presentation.Because of its rarity, literature about laryngeal chondrosarcoma is mainly made up of case reports and small case series.Therefore, it is important to add any information regarding this pathology.The aim of this article was to present and discuss a new case of chondrosarcoma located in the thyroid cartilage in a 63-year-old woman.

The incidence of both benign and malignant bone tumors arising in the hand is relatively low in comparison with other locations. Although the overwhelming majority of these tumors are benign, even benign tumors can be locally destructive and compromise hand function. Intralesional tumor excision is the most appropriate surgical intervention for many benign bone tumors of the hand; however, destructive or malignant tumors may require wide local excision or even amputation to achieve complete tumor eradication. The purpose of this review article is to provide an overview of the pertinent benign and malignant bone tumors that may be encountered by hand surgeons. Clinical presentation, radiographic features, recommended workup, and available treatment options are all reviewed.

Chondrosarcomas are malignant neoplasms of mesenchymal origin and represent a heterogeneous group of tumors ranging from indolent, low-grade lesions to aggressive, high-grade neoplasms. The early diagnosis and treatment of chondrosarcomas is paramount to achieving a better prognosis. Multiple imaging modalities have been used for the purpose of initial detection, characterization, and staging, as well as for the performance of image-guided biopsies. As imaging techniques continue to evolve, radiologists are assuming an increasingly important role in the management of chondrosarcomas. This review describes the imaging characteristics of chondrosarcomas on multiple modalities and emphasizes the imaging features that may assist in differentiating these tumors from their benign counterparts, enchondromas and osteochondromas, which frequently still pose challenging diagnostic dilemmas.

Treatment of Hodgkin disease (HD) with chemoradiotherapy in children is associated with increased risk for developing secondary neoplasms. Parathyroid adenoma (PTA) and chondrosarcoma (CS) are quite rare types of secondary neoplasms after HD. We describe a 5-year-old boy with stage IV HD, successfully treated with MOPP (mechlorethamine, vincristine, procarbazine, and prednisone)/ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy followed by 35 Gy mantle radiotherapy who developed primary hyperparathyroidism because of benign PTA at the age of 20 years, and died of CS in thoracic vertebrae at the age of 22 years. Consecutive occurrence of PTA and CS after treatment of pediatric HD, to the best of our knowledge, has not been reported earlier.

Chordoma originates from embryonic notochordal remnants in the midline along the spinal axis and is characterized by cords and lobules of neoplastic cells arranged within myxoid matrix. Because of histologic similarities with myxoid matrix and overlapping immunohistochemical profile, chondrosarcoma, myxopapillary ependymoma, and chordoid meningioma enter in the histologic differential diagnosis at this site. Therefore, the judicious use of a panel of selected immunostains is unquestionably helpful in diagnostically challenging cases. To find useful immunohistochemical markers for assisting in differential diagnosis between chordoma and other tumors with chordoid morphology, an immunohistochemical study using D2-40, epithelial membrane antigen (EMA), pan-cytokeratin (panCK), glial fibrillary acidic protein (GFAP), S-100 protein, galectin-3, neural cell adhesion molecule (NCAM), beta-catenin, E-cadherin, and carcinoembryonic antigen was performed on 14 chordomas, 7 chondrosarcomas, 9 myxopapillary ependymomas, and 4 chordoid meningiomas. Chordoma typically showed positive for EMA and panCK and negative for D2-40 and GFAP; whereas chondrosarcoma revealed positive for D2-40, and negative for EMA, panCK, and GFAP; myxopapillary ependymoma positive for GFAP and negative for EMA; and chordoid meningioma positive for EMA, and negative for panCK and GFAP. On the basis of our immunohistochemical study, a panel of D2-40, EMA, panCK, and GFAP allowed the correct recognition of all tumors examined. Other immunohistochemical markers including S-100 protein, galectin-3, NCAM, beta-catenin, E-cadherin, and carcinoembryonic antigen were of little value in differential diagnosis. In summary, the best immunohistochemical markers useful for the evaluation of tumors with chordoid morphology were D2-40, EMA, cytokeratin, and GFAP. D2-40 was a true chondroid marker to be useful for the differential diagnosis with chordoma.

We describe a case of a rare primary chondrosarcoma of the heart in a 62-year-old woman who was referred to our institution with a diagnosis of left atrial undetermined mass. Despite utilization of transesophageal echocardiography and multislice computed tomography imaging, the definitive diagnosis of chondrosarcoma was achieved only with histology of the operative specimen. The tumor was extending from the left atrium to the left pulmonary veins causing obstruction of the venous drainage and a clinical and radiological picture of persistent respiratory infection. Surgery achieved only partial resection of the mass, including the removal of the obstruction to the pulmonary venous drainage. After surgery, a rapid healing of the respiratory infection was observed; however, 3 months later, the tumor was already regrowing rapidly.

Study Design: Case report., Objective: To report on thoracic spinal cord compression caused by a mass in a 66-year-old female with new onset of myelopathic symptoms and a history of multiple hereditary exostoses., Summary of Background Data: To our knowledge, there have been no previous reports of spinal cord compression in a patient with multiple hereditary exostoses caused by breast adenocarcinoma metastatic to osteochondromas of the spine. METHODS.: Chart, pathologic, and radiographic documentation of the preoperative and postoperative clinical course of the patient was used., Results: The patient had resolution of her neurologic symptoms following wide surgical excision, decompression, and stabilization from T2 to T10. The patient's mass was found to be breast adenocarcinoma metastatic to osteochondromas of the spine., Conclusions: When faced with a patient with a history of multiple hereditary exostoses with new onset of myelopathic symptoms and a mass compressing the spinal cord, the clinician's differential should be broad and always initially include a metastatic lesion, osteochondroma, or chondrosarcoma.

The goal of this study was to evaluate the diagnostic relevance of the expression of growth factors in cartilaginous tumors and to investigate on the possible correlation with grade, local recurrence, metastatic potential, and survival. Expression of VEGF, PDGF, FGF1, TFGbeta2, TNFalpha, Ki-67, and p53 was analyzed in 21 cases of benign and malignant cartilaginous tumors using immunohistochemistry. Immunohistochemical staining was performed on sections from paraffin-embedded tissue. The correlation of these markers' expression and grading or clinical outcome was also evaluated. Immunohistochemistry revealed a high correlation between grading and VEGF-positive staining (P=0.001). In addition, a correlation with local recurrence was found in cases with a positive expression of Ki-67 (P=0.035), TGFbeta (P=0.007), PDGF (P=0.007), and p53 (P=0.0455), with a time-related association. These data suggest a progressive modification in the biologic behavior of malignant cartilaginous tumors. VEGF could be used as a marker in the preoperative surgical assessment of chondrosarcoma. New therapeutic strategies could be considered for VEGF-positive cases. Positive expression of TGFbeta and PDGF seems to be a predictor of clinical outcome.

Objective: To determine the contribution of 18fluoro-deoxyglucose positron emission tomography (18FDG PET) in distinguishing benign from malignant osteochondromas., Materials and Methods: From 2000 to 2004, 10 patients (4 females, 6 males, 12 to 64 years old) with osteochondromas were referred for whole body PET by clinicians for metabolic evaluation before planned surgery for pain or cosmesis. Two PET readers and 1 pathologist, blinded to their diagnoses and imaging studies (except for radiographs), correlated results post surgery. The PET average and maximum standard uptake value (SUV) generated by computer for Regions of Interest and correlated with radiographs, were based on axial 3.37 mm thick, 3 x 3 mm pixel images. Since SUVs vary from site to site depending on scanning devices and techniques, a 2.0 maximum cutoff SUV separated benign and malignant osteochondromas based on our standard protocols and specific equipment (Siemens Ecat Exact Knoxville, Tenn) used with our prior oncological studies., Results: Results showed that no definitive statistical conclusions could be drawn due to the small number of patients involved, but they were, nevertheless, deemed promising., Conclusions: The 18FDG whole body PET aided the identification of malignant osteochondromas, their local recurrence and metastases by both displaying and quantifying their metabolic activity. Although the current study is limited by a small cohort, which precludes statistical analysis, additional experience with PET analysis of osteochondromas may further support its value as a physiological parameter supplementing anatomically based imaging modalities most often used for their evaluation.

Objective: To highlight a case of cochlear implantation in the setting of ipsilateral petrous apex chondrosarcoma., Background: A patient with bilateral progressive hearing loss was incidentally found to have a destructive right petrous apex lesion on computed tomography before cochlear implantation. The patient had no associated symptoms and a magnetic resonance imaging scan was obtained, narrowing the differential diagnosis. A middle cranial fossa approach was performed for synchronous biopsy of the lesion and cochlear implantation., Results: Frozen sections revealed a low-grade chondroid lesion, and a Med-El Combi 40+ cochlear implant with a split electrode array was inserted via the middle fossa. Final pathologic examination revealed a Grade I chondrosarcoma. The patient suffered no complications postoperatively and was followed-up over 5 years with serial computed tomographic scans and clinical examinations. No additional treatment was administered. Eighteen months postoperatively, the patient experienced episodic vertigo. There were no new findings on computed tomography, and the vertigo improved with a low-salt diet. Otherwise, the patient had excellent hearing results, and the lesion has not progressed under observation., Conclusion: The implications of observing low-grade chondrosarcomas in well-selected patients and the unique aspect of cochlear implantation on the affected side are discussed.

Aim: Chondroblastoma and clear cell chondrosarcoma are uncommon skeletal neoplasms that have a strong tendency to involve the epiphysis of long bones. They also share some overlapping histological features. Thus, it can be difficult both radiographically and histologically to distinguish these neoplasms. So far there are no immunohistochemical markers available that have been shown to be helpful in differentiating these neoplasms., Methods: In our study of a series of clear cell chondrosarcomas (n = 15) and chondroblastomas (n = 35), S100, vimentin, aggrecan and collagen type II were detected by immunohistochemistry., Results: We detected immunohistochemical evidence of type II collagen within both the extracellular matrix-rich (chondroid) and matrix-poor areas in all 15 cases of clear cell chondrosarcoma. In contrast, immunohistochemical analysis failed to show staining of collagen type II in any of the 35 chondroblastomas. Other markers, including S100 protein, vimentin and aggrecan proteoglycan were tested in parallel and found to be focally positive in both neoplasms., Conclusion: Therefore, our data show that in cases when clear cell chondrosarcoma and chondroblastoma pose a diagnostic challenge, the presence of type II collagen in the extracellular tumour matrix significantly supports the diagnosis of clear cell chondrosarcoma and aids in distinguishing it from chondroblastoma.

Extraskeletal myxoid chondrosarcoma (EMC) is an intriguing entity with a broad morphologic spectrum that overlaps features found in other benign and malignant mesenchymal tumors. This phenotypic plasticity should be known to avoid erroneous diagnosis. The identification of older age, larger tumor size, proximal tumor location, and metastatic disease as independent adverse predictors of survival is useful in achieving optimal treatment and follow-up in high-risk patients.

Patients with Ollier's disease (multiple skeletal enchondromas) and Maffucci's syndrome (multiple enchondromas associated with subcutaneous hemangiomas) may develop skull base chondrosarcomas or low-grade astrocytomas as a delayed consequence of these disorders. We report three patients with Ollier's disease and Maffucci's syndrome who had diplopia as the initial manifestation of intracranial tumors. Since patients with Maffucci's syndrome and Ollier's disease are at risk for the delayed development of brain and systemic neoplasms, neuroophthalmologists must be aware of the need for long-term surveillance in patients affected by these conditions.

Objective: The accurate diagnosis of different petrous apex lesions is increasingly common as a result of modern imaging techniques, combining computed tomography and magnetic resonance imaging. The clinical features, diagnostic evaluation, imaging, and treatment outcomes of patients with petrous apex lesions are reviewed., Study Design: Retrospective case review., Setting: Private practice tertiary otologic referral center., Patients: Sixty-six patients treated at the House Ear Clinic in the last 2 decades for a lesion of the petrous apex. Lesions included cholesterol granuloma, cholesteatoma, and chondrosarcoma, among others. Mean follow-up time was 27 months and ranged from 1 month to 10 years., Intervention(s): Cholesterol granulomas were treated with drainage procedures, solid tumors were surgically removed using primarily the middle fossa or infratemporal fossa approaches., Results: The most common presenting symptoms were hearing loss, dizziness, headaches, and tinnitus. Decreased cranial nerve V function was present in 22%. The most common cystic lesion was cholesterol granuloma, which constituted 60% of all lesions in the study, followed by cholesteatoma (9%). Chondrosarcomas were the most common solid lesion (6% of all lesions). Asymmetric pneumatization and retained secretions give radiographic findings commonly overdiagnosed as lesions of the petrous apex., Conclusions: Lesions of the petrous apex can be diagnosed accurately by CT and MRI and can be divided into cystic and solid lesions. Cholesterol granulomas are by far the most common lesion found in this site and can be drained with minimal morbidity via the infracochlear approach. Solid tumors may require extensive exposure and a combined skull base approach for complete removal.

We present a unique case of aggressive osteoblastoma arising from thyroid cartilage. A 52-year-old man presented with a 10 month history of neck discomfort but without frank pain. CT and MR examinations disclosed a well defined mass arising from the thyroid cartilage. This lesion had areas of coarse calcifications and a central area of lucency. The appearance suggested chondrosarcoma. Hemilaryngectomy was performed to remove the mass en bloc. Surgical pathology diagnosed aggressive osteoblastoma arising from thyroid cartilage.

Infrequently encountered tumors involving the middle ear cleft can cause symptoms and signs that are identical with those of acute or chronic otitis media. Selection of patients who require a more thorough evaluation is predicated upon a high index of clinical suspicion. Integration of the results of a preoperative neuroradiologic evaluation, including high resolution computerized tomography, magnetic resonance imaging, and either conventional or magnetic resonance angiography, may suggest the histopathologic nature of the lesion and direct appropriate treatment. The authors present their experience with the management of 11 patients who had either malignant or benign middle ear lesions that were initially believed to represent infectious middle ear disease. The perioperative decision making process and patient outcomes are compared to other historical reports.

Objective: To assess the role of MRI in evaluating periosteal chondrosarcoma in the foot, an anatomically complicated location., Materials and Methods: Three cases of surgically and histologically confirmed periosteal chondrosarcomas occurring in the foot (58-year-old woman, 57-year-old woman, and 63-year-old man) were retrospectively reviewed with an emphasis on MR findings., Results: Magnetic resonance successfully delineated the hypovascular nature and lobulating pattern of the lesion suggesting the cartilaginous component, the periosteal location with sparing bone marrow, and the extent of involvement of adjacent structures. These findings were either not seen or less clearly seen on CT in the former two cases., Conclusion: In cases of periosteal chondrosarcomas in the foot MRI can play a significant role both in the characterization of the lesion and in planning surgical therapy.

Skull base chondrosarcoma and chordoma are rare tumors that generally have a poor prognosis. In 1973, Heffelfinger et al described a chondroid variant of chordoma, called chondroid chordoma that was found to have a significantly better prognosis than classic chordoma. However, recent evidence suggests that many of the tumors diagnosed as chondroid chordoma may, in fact, be low-grade myxoid chondrosarcomas. This report presents the diagnosis and treatment of two cases of skull base tumor that were diagnosed preoperatively as schwannoma because they were thought initially to be centred on the jugular foramen. Initial histologic evaluation suggested chondroid chordoma, but immunohistologic techniques and a review of the literature led to a diagnosis of low-grade myxoid chondrosarcoma.

A retrospective CT, MR, and histopathologic study was performed in five patients with histologically verified low-grade myxoid chondrosarcoma of the base of the skull. In four patients, the tumor originated off the midline and was associated with bone destruction at the petrous apex near the petrooccipital fissure. Tumor extent included the cerebellopontine angle in three patients and the parasellar area in two patients. The fifth tumor originated on the midline and was associated with destruction at the dorsum sellae. Three tumors contained calcifications, whereas two lesions were mostly isodense with brain on CT scan. All tumors were hypointense on T1-weighted MR images and very intense on T2-weighted images except for areas of signal void consistent with calcifications. Light microscopy revealed islands of mature hyaline cartilage in an abundant myxoid ground substance. Histology and immunocytochemical analysis were consistent with a low-grade myxoid chondrosarcoma. The CT and MR features of low-grade myxoid chondrosarcoma are comparable with those of chordoma. Chordoma usually arises from the midline, but cases with origin from the lateral portion of the clivus or the petrous apex have been described. Low-grade myxoid chondrosarcoma has distinct histologic and immunocytochemical features and includes lesions formerly called "chondroid chordomas."

MR studies of five chondrosarcomas and three enchondromas were performed with intravenous Gd-DTPA administration. All tumors showed enhancement of scalloped margins and curvilinear septa (ring-and-arc pattern) on T1-weighted SE sequences with Gd-DTPA. On radiologic-pathologic correlation, the enhanced areas corresponded to fibrovascular bundles surrounding hyaline cartilage lobules. The rings and arcs of enhancement with Gd-DTPA on MR is a reflection of the lobulated growth pattern of cartilaginous tumors and therefore helpful in differential diagnosis of bone tumors.

Soft tissue tumors of seven patients were imaged with magnetic resonance imaging (MRI) prior to operative resection. In four cases, gross surgical specimen biopsy sites were broadly selected from areas of diverse signal intensity. A subsequently developed "grid analysis" technique, used in three additional patients, better localized differing zonal intensities within individual gross specimens. Further investigation of this technique is warranted, since MR images, when analyzed by means of a detailed grid technique, appear to enhance histologic diagnostic accuracy. Examination of larger segments of inhomogeneous soft tissue tumors is facilitated, while pathologists' sampling time is diminished.

Myasthenia gravis (MG) commonly presents with weakness and fatigability of the lids and extraocular muscles, which respond to treatment with anticholinesterase medication. However, certain intracranial mass lesions may mimic these features of MG; alternatively, MG may mask the signs of a coexistent intracranial mass. We describe 8 patients originally diagnosed as having MG by knowledgeable clinicians, in whom an intracranial lesion instead of, or in addition to, MG was later identified. The lesions included parasellar tumors and aneurysms. In patients presenting with clinical features of ocular MG, it is therefore essential to establish a definite diagnosis of MG, to exclude other possible causes of "pseudomyasthenia," and to exclude other diseases that might be masked by coexisting myasthenic weakness. We recommend that patients with clinical features of MG limited to the ocular or cranial musculature be thoroughly evaluated for intracranial mass lesions, using CT or MRI if warranted.