Chondrosarcomas of the base of the skull in Ollier's disease or Maffucci's syndrome--three case reports and review of the literature

Non-chordomatous clival bony tumors: A rare experience and systematic literature review

BACKGROUND

Non-chordomatous bony tumors of the clivus are extremely rare. Site, extent, and aggressiveness of tumor limits the extent of resection. It poses challenge to the neurosurgeons due to the complexity of anatomy. There is paucity of literature exclusively on non-chordomatous bone tumors of the clivus in young adults.

OBJECTIVES

To analyze the clinical presentation, imaging findings, surgical approach, complications, and outcome of primary clival bony tumors in young adults.

METHODS

We retrospectively reviewed children and young adults with primary clival bony tumors excluding chordoma who underwent surgical resection between years 2010 and 2023 in our center. We analyzed the demographic details, imaging findings, operative variables, perioperative complications, length of stay, complications, and outcome at latest follow-up.

RESULTS

The mean age was 17.5 ± 1.73 years (range 16 to 19 years). Headache was the presenting complaint in all four patients (100%). The mean duration of symptom was 7.25 ± 3.2 months (range 5 to 12 months). The tumor was localized in clivus in all four patients (100%). The mean length of stay in hospital was 30.5 ± 13.48 days (range 11 to 40 days). All patients underwent surgical treatment. Surgical approaches used were anterior approach in four patients (100%). Gross total excision was performed in one patient (25%), sub-total excision was performed in two patients (50%), and tumor decompression was performed in one patient (25%). Of these, three were designated as having benign tumors and one had a malignant tumor. There was no perioperative mortality. There was one mortality (25%) on 2 months follow-up due to tumor progression. Three patients (75%) had improved symptomatically at latest follow-up. Two patients (50%) received adjuvant chemoradiotherapy. The mean follow-up was 38 ± 39.29 months (range 2 to 72 months).

CONCLUSION

Non-chordomatous bony tumors of the clivus are rare and often underestimated. Surgery is the treatment of choice. Tumor consistency and adhesion to critical neurovascular structures precludes gross total resection. Various approaches are in the armamentarium. Approach to be decided based on the expertise of the neurosurgeon to achieve safe maximal resection. Multidisciplinary approach is mandatory for streamlined management. Adjuvant therapy is decided based on the residual tumor following surgery.

A rare presentation of Maffucci syndrome: A case report and literature review

Maffucci syndrome is an extremely rare disease which can manifest symptoms as early as childhood. It is estimated that there have been <300 cases reported globally; however, this number is likely to be an underestimate. Maffucci syndrome is characterized by multiple enchondromas and soft tissue hemangiomas, which can cause growth and developmental malformations. In addition to bone deformities, pathological fractures and a loss of mobility, patients with Maffucci syndrome may develop secondary central chondrosarcoma and have a higher risk of developing non-skeletal malignant tumors, such as gliomas and mesenchymal ovarian tumors. The present study provides information for clinicians about this disease through the use of imaging, physical examinations, clinical manifestations and the treatment strategy used. There is need to summarize the existing cases of this disease around the world and produce an effective framework for the diagnosis, treatment and prevention of Maffucci syndrome, in order to better understand this disease. The present study reports on a 15-year-old male diagnosed with Maffucci syndrome. . Due to the risk of malignant tumor development in the absence of effective treatment, regular and careful observation through monitoring of tumor markers and imaging studies is important for patients with Maffucci syndrome. As cases of this disease are rare and case data is limited, it is difficult to create a clear treatment plan. There is an urgent need to establish a case database of Maffucci syndrome patients and explore its pathogenesis for early diagnosis, treatment and prevention of disease.

Primary Skull Base Chondrosarcomas: A Systematic Review

Simple Summary

Primary skull base chondrosarcomas (SBCs) may carry significant tumor-burden by causing severe cranial nerve neuropathies. Current treatment strategies mainly focus on surgical resection and radiotherapy protocols, with a wide range of findings in terms of efficacy and safety. The aim of our systematic review was to comprehensively analyze the current literature on primary SBCs, describing clinical and radiological characteristics, available management strategies, treatment outcomes, and prognoses. We found that most primary SBCs show benign slow-growing patterns but may cause neurological deficits by compressing critical neurovascular structures. Open surgical approaches favor maximal resection with acceptable complication rates, but only a few studies reported the use of newer endoscopic approaches. Proton-based, photon-based, and carbon-based radiotherapy protocols may also allow safe and effective local tumor control as adjuvant treatments or stand-alone strategies in patients not eligible to undergo surgery. Overall, primary SBCs’ prognoses proved to be favorable and comparable to benign skull base neoplasms.

Abstract

Background: Primary skull base chondrosarcomas (SBCs) can severely affect patients’ quality of life. Surgical-resection and radiotherapy are feasible but may cause debilitating complications. We systematically reviewed the literature on primary SBCs. Methods: PubMed, EMBASE, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA guidelines to include studies of patients with primary SBCs. Clinical characteristics, management strategies, and treatment outcomes were analyzed. Results: We included 33 studies comprising 1307 patients. Primary SBCs mostly involved the middle-fossa (72.7%), infiltrating the cavernous-sinus in 42.4% of patients. Cranial-neuropathies were reported in 810 patients (62%). Surgical-resection (93.3%) was preferred over biopsy (6.6%). The most frequent open surgical approaches were frontotemporal-orbitozygomatic (17.6%) and pterional (11.9%), and 111 patients (21.3%) underwent endoscopic-endonasal resection. Post-surgical cerebrospinal-fluid leaks occurred in 36 patients (6.5%). Radiotherapy was delivered in 1018 patients (77.9%): photon-based (41.4%), proton-based (64.2%), and carbon-based (13.1%). Severe post-radiotherapy complications, mostly hypopituitarism (15.4%) and hearing loss (7.1%) were experienced by 251 patients (30.7%). Post-treatment symptom-improvement (46.7%) and reduced/stable tumor volumes (85.4%) showed no differences based on radiotherapy-protocols (p = 0.165; p = 0.062). Median follow-up was 67-months (range, 0.1–376). SBCs recurrences were reported in 211 cases (16.1%). The 5-year and 10-year progression-free survival rates were 84.3% and 67.4%, and overall survival rates were 94% and 84%. Conclusion: Surgical-resection and radiotherapy are effective treatments in primary SBCs, with acceptable complication rates and favorable local tumor control.

Surgery of the lateral skull base: a 50-year endeavour

Disregarding the widely used division of skull base into anterior and lateral, since the skull base should be conceived as a single anatomic structure, it was to our convenience to group all those approaches that run from the antero-lateral, pure lateral and postero-lateral side of the skull base as “Surgery of the lateral skull base”. “50 years of endeavour” points to the great effort which has been made over the last decades, when more and more difficult surgeries were performed by reducing morbidity. The principle of lateral skull base surgery, “remove skull base bone to approach the base itself and the adjacent sites of the endo-esocranium”, was then combined with function preservation and with tailoring surgery to the pathology. The concept that histology dictates the extent of resection, balancing the intrinsic morbidity of each approach was the object of the first section of the present report. The main surgical approaches were described in the second section and were conceived not as a step-by-step description of technique, but as the highlighthening of the surgical principles. The third section was centered on open issues related to the tumor and its treatment. The topic of vestibular schwannoma was investigated with the current debate on observation, hearing preservation surgery, hearing rehabilitation, radiotherapy and the recent efforts to detect biological markers able to predict tumor growth. Jugular foramen paragangliomas were treated in the frame of radical or partial surgery, radiotherapy, partial “tailored” surgery and observation. Surgery on meningioma was debated from the point of view of the neurosurgeon and of the otologist. Endolymphatic sac tumors and malignant tumors of the external auditory canal were also treated, as well as chordomas, chondrosarcomas and petrous bone cholesteatomas. Finally, the fourth section focused on free-choice topics which were assigned to aknowledged experts. The aim of this work was attempting to report the state of the art of the lateral skull base surgery after 50 years of hard work and, above all, to raise questions on those issues which still need an answer, as to allow progress in knowledge through sharing of various experiences. At the end of the reading, if more doubts remain rather than certainties, the aim of this work will probably be achieved.

Skull Base Chondrosarcoma Caused by Ollier Disease: A Case Report and Literature Review

BACKGROUND

Ollier disease (OD) is a rare, nonhereditary bone disease that is characterized by the presence of multiple enchondromatosis (3 or more) with a typical asymmetric distribution which is mainly confined to the appendicular skeleton. OD's most serious complication is the transformation of an enchondroma into chondrosarcoma. The most common sites for chondrosarcoma are in the pelvic and shoulder bones, the superior metaphyseal and diaphyseal regions of the extremities. However, the cranium is an extremely rare site for chondrosarcoma because of OD.

CASE DESCRIPTION

We report the case of a 27-year-old woman who was admitted to our hospital with paroxysmal headaches over 1 month and left ptosis for 2 weeks. Magnetic resonance imaging (MRI) scan revealed a mass was located at the left side of the parasellar area. The mass was surgically removed, and histopathologic examination confirmed chondrosarcoma grade I. During follow-up, more imaging examinations and pathologic examination confirmed the final diagnosis was OD.

CONCLUSIONS

Intracranial chondrosarcoma caused by OD is extremely rare but should be considered in the differential diagnosis when primary chondrosarcoma is diagnosed. Preoperative diagnosis is challenging, and definitive diagnosis requires immunohistochemical examination and systematic examination of the body. Surgical resection is the most effective therapy for rapid relief of symptoms. For patients with OD with normal intracranial MRI, long-term follow-up is necessary.

Maffucci syndrome and intracranial chondrosarcomas: a case report featuring spontaneous resolution of sixth nerve palsy

Maffucci syndrome is a rare disease process characterized by enchondromatosis with cutaneous hemangiomatosis. We report a 20-year-old woman with Maffucci syndrome with a 5-day history of diplopia. She was found to have a left sixth nerve palsy due to a parasellar chondrosarcoma. Three weeks later, the patient's diplopia spontaneously resolved. This unusual clinical course prompted us to review frequency of sixth nerve palsy with skull base neoplasms and the phenomenon of spontaneous resolution of diplopia.

Endoscopic Endonasal Approach in Skull Base Chondrosarcoma Associated with Maffucci Syndrome: Case Series and Literature Review

BACKGROUND

Maffucci syndrome is a nonhereditary disorder in which patients develop multiple enchondromas and cutaneous, visceral, or soft tissue hemangiomas. The potential malignant progression of enchondroma into a secondary chondrosarcoma is a well-known fact. Nevertheless, chondrosarcoma located at the skull base in patients with Maffuci syndrome is a very rare condition, with only 18 cases reported in the literature.

CASE DESCRIPTION

We report 2 other cases successfully treated through an expanded endoscopic endonasal approach and discuss the condition based on the literature review.

CONCLUSIONS

Skull base chondrosarcoma associated with Maffucci syndrome is a rare condition. The disease cannot be cured, therefore surgical treatment should be performed in symptomatic patients aiming for maximal tumor resection with function preservation. The endoscopic endonasal approach is a safe and reliable alternative for the management of these tumors.

Enchondroma of the nasal septum due to Ollier disease: a case report and review of the literature

BACKGROUND

Morbus Ollier is characterized by the presence of multiple enchondromas (ie, benign intraosseous cartilaginous lesions). Although their manifestation in the limb bones is well described, only a few cases with ear, nose, and throat (ENT) involvement, primarily arising from the skull, have been reported. The malignant transformation toward slowly growing low-grade chondrosarcomas is the most severe form of progression.

METHODS

We report a unique case of a 54-year-old patient with Ollier disease with an extensive nasal enchondroma apparently eroding the middle nasal concha and expanding to the lateral nasal wall that raised suspicion of malignant transformation.

RESULTS

Radiological and histological features of enchondromas can be controversial and seem to have limited sensitivity to exclude low-grade malignancy. The clinical symptoms play a decisive role in differentiation between enchondromas and low-grade chondrosarcomas.

CONCLUSION

Surgery remains the only effective solution in removing an enchondroma and preventing the tendency toward malignant transformation.

Diagnosis and microsurgical treatment of chondromas and chondrosarcomas of the cranial base

Chondromas and chondrosarcomas of the cranial base are rare neoplastic diseases. The aim of the present study was to evaluate the diagnosis and microsurgical treatment of these difficult cranial base tumors. A total of 19 patients who underwent microsurgery were pathologically diagnosed with cranial base chondromas or chondrosarcomas and their clinical data was reviewed. The chondromas and chondrosarcomas of the cranial base in the present study commonly originated in the sphenopetrosal, sphenoclival or petroclival junctions, and the majority were located in the parasellar region of the middle cranial base extradurally. The most frequent symptoms were headaches and cranial nerve palsy, and the Karnofsky performance score (KPS), assessed pre-operatively, averaged at 87.1. A frontotemporal or preauricular subtemporal-infratemporal approach was used in 11 cases, a tempo-occipital transtentorial or presigmoid supratentorial-infratentorial approach was employed in six further cases, and the far-lateral or retrosigmoid approach was applied in the remaining two cases. A total or near-total tumor removal was secured in 13 cases, while a subtotal removal was obtained in another five and a partial removal was achieved in one case. The most common post-operative complications included cranial nerve palsy and cerebrospinal fluid leakage, but there were no post-operative fatalities. A total of 15 patients were followed up for a mean of 67.2 months (range, 5–140 months), and 13 (76.5%) of these patients were living normal lives (KPS, 80–90). There were two patients with recurrent tumors. The neuroradiological examinations and the presenting symptoms and signs allow the pre-operative diagnosis to be presumed for the majority of cranial base chondromas or chondrosarcomas. Surgical resection is the key treatment for these tumors, and this treatment is known to improve the survival rates.

Skull base chondrosarcoma: evidence-based treatment paradigms

Chondrosarcomas are indolent but invasive chondroid malignancies that can form in the skull base. Standard management of chondrosarcoma involves surgical resection and adjuvant radiation therapy. This review evaluates evidence from the literature to assess the importance of the surgical approach and extent of resection on outcomes for patients with skull base chondrosarcoma. Also evaluated is the ability of the multiple modalities of radiation therapy, such as conventional fractionated radiotherapy, proton beam, and stereotactic radiosurgery, to control tumor growth. Finally, emerging therapies for the treatment of skull-base chondrosarcoma are discussed.

A case of Maffucci syndrome

The Maffucci syndrome consists of a combination of multiple enchondromas and haemangiomas. It appears in the first two decades of life, with no family history. In this case we are reporting about a 26-year-old female who had suffered from multiple enchondromas since the age of two. At the age of nine, the patient presented with additional haemangiomas, which facilitated making proper diagnosis. She now presents with a massive lesion of her left upper extremity. The patient had initially rejected operative treatment when the disease was at early stages. At later stages, a more complex reconstruction of the hand would have been necessary to secure hand function. This procedure that sometimes induces a risk related to potential necessity of blood transfusion was rejected by the patient for religious reasons. Amputation of the extremity was therefore the last resort procedure.

Pediatric thalamic glioblastoma associated with Ollier disease (multiple enchondromatosis): a rare case of concurrence

Ollier disease and Maffucci syndrome are rare syndromes in which there is deforming dysplasia of cartilage, primarily but not exclusively involving the metaphyses and diaphyses of long bones. In a minority of patients, dysplasia can lead to sarcomatous degeneration, producing chondrosarcomas. There also appears to be an association with other neoplasms. Little has been written about the association between Ollier disease and intracranial tumors, and these papers have largely consisted of case reports in adults. The authors present the case of a 6-year-old girl with left arm osseous changes consistent with Ollier disease and a biopsy-proven thalamic glioblastoma multiforme. They then examine the co-occurrence of brain tumors in conjunction with a dyschondroplasia syndrome in children and adolescents to assess the presentation, treatment offered, and disease course of similar cases. Eight other such cases were identified, 6 in patients with Ollier disease (ranging in age from 7 to 18 years), and 2 with Maffucci syndrome (both in late adolescence). Including our own patient, 7 of the 9 cases of comorbid dyschondroplasia and intracranial malignancy occurred in girls. Some patients presented soon after the acute onset of symptoms, and others had a more subtle, protracted course over as many as 2 years. Some tumors were deemed resectable and others not. In only 1 instance was follow-up beyond 1 year reported.

[Chondrosarcomas of skull base treatment]

BACKGROUND AND PURPOSE

Skull base chondrosarcomas are rare. Gross total removal is the treatment of choice, but can be difficult depending on the closeness of noble structures. Proton beam therapy can be associated in most cases.

METHODS

Retrospective study of five cases treated in 13 years and study of the literature.

RESULTS

Median age of patients was 34 years [28-46]. Cranial nerve palsy was the common clinical presentation. Tumor location was variable but always off midline. Treatment was surgical in all patients with a maximal resection and proton beam therapy associated for two cases. Surgical complications were rare with cranial nerve palsy as the main side effect. Outcomes were good with a median follow-up of 12.4 years [4.3-16.2].

DISCUSSION

The review of the literature showed that chondrosarcomas of skull base are rare. The best outcome is achieved with total surgical resection. Medical imaging can only give clues to the diagnosis. Pathology is required to obtain a precise immunohistochemistry diagnosis. Multidisciplinary treatment using proton beam therapy and surgical removal enables a good local control (90-100%) at 5 years with good quality-of-life. It is difficult to determine how many cases have been published (around 220 cases in the literature) since many surgical or radiotherapy series included the same patients.

The association between intracranial tumours and multiple dyschondroplasia (Ollier's disease or Maffucci's syndrome): do children and adults differ?

In Ollier's disease (OD) and Maffucci's syndrome (MS), there is deforming dysplasia of cartilage, primarily but not exclusively involving the metaphyses and diaphyses of long bones. In a minority of patients with either of these rare syndromes, dysplasia can lead to sarcomatous degeneration, producing chondrosarcomas. There also appears to be an association with other neoplasms, which can include intracranial tumours. The primary objective of the current paper was to compare children/adolescents who have either OD or MS and an intracranial malignancy with their adult counterparts. All relevant cases in the medical literature were identified by electronically searching PubMed, SciSearch, Scientific Commons, Springer Link, and Google. Translate DotNet and Babelfish were used to translate non-English text. Non-parametric Pearson chi-square analyses were used to compare youths versus adults with respect to gender and geographic distribution (by continent), tumour histology and site of lesion, and the underlying enchondromatosis syndrome (OD vs. MS). All tests were 2-tailed, and P < 0.05 represented a statistically-significant difference. Forty-six patients with 47 intra-cranial malignancies were identified, with nine of the patients being 18 years old or less and categorized as youths. The incidence of intracranial chondrosarcomas peaked in the fourth decade of life, in parallel with the peak number of MS cases; conversely, both non-sarcomas and OD peaked in the third decade of life. Six of nine youths (67%) versus 17 of 36 adults with gender data (47%) were female (P = 0.30). There was no difference in geographic distribution by continent (P = 0.82). Four youths (44%) versus 16 adults (43%) had a chondrosarcoma (P = 0.95), and there was no statistically significant difference by tumour site (P = 0.42). However, seven (77%) of the youths had Ollier's disease as their underlying enchondromatosis syndrome, versus just 17 (46%) of the adults, a difference that approached statistical significance (P = 0.086). The association between enchondromatosis and intracranial malignancy seems to be roughly the same in youths versus adults, though Ollier's disease cases appear to predominate among youths.

Ollier disease

BACKGROUND

Ollier disease is a rare, nonfamilial disorder characterized by multiple enchondromatosis with an asymmetric distribution and areas of dysplastic cartilage. Clinical manifestations usually start with local pain, bone swelling, and palpable bony masses, often associated with bone deformity. Intracranial enchondromas arise from the skull base because of its cartilage embryological derivation. Headache and cranial nerve palsy are the most prominent clinical findings. The only effective treatment is represented by surgery that allows to resect the tumors and to treat their complications, such as pathological fractures, growth defect, and neurological symptoms.

METHOD

We report on a 12-year-old boy affected with Ollier disease and operated on for a skull base enchondroma. The tumor was partially removed through a right pterional approach to the cavernous sinus. Serial postoperative magnetic resonance imaging showed an increasing residual tumor and the patient underwent radiation therapy.

CONCLUSION

Surgery remains the main therapy for intracranial enchondromas. Radiotherapy is required in case of sarcomatous evolution or when a gross total tumor resection is not feasible, as in the present case.

Maffucci syndrome associated with a pituitary adenoma and a probable brainstem tumor

Malignancies are a common feature of Maffucci syndrome, with chondrosarcomas being the most common tumor type. The authors present the first case of Maffucci syndrome associated with a pituitary adenoma and a probable brainstem glioma and review the literature concerning intracranial tumors related to this disease. They report the case of a 35-year-old woman with Marfucci syndrome (diagnosed when she was 22 years old) who presented with complaints of decreased visual acuity and visual field defect. Neuroimaging revealed a pituitary macroadenoma and a suspected brainstem tumor. The macroadenoma was partially removed. There were no postoperative complications and the patient experienced rapid improvement in visual acuity. On follow-up examination 2 years later, the lesion in the pons showed the same dimensions. No sarcomatous changes of enchondromas or hemangiomas occurred. To the authors' knowledge, including the present case, only 7 cases of Maffucci syndrome associated with glioma and 7 cases associated with pituitary adenoma have been reported in the literature. This report emphasizes that patients with this disease are at a higher risk for primary intracranial tumors and reinforces the concept of the multiplicity of tumors that may arise in this syndrome. It also underscores the importance of early diagnosis, regular clinical surveillance, and follow-up studies of these patients.

Chondrosarcoma of the skull base in Maffucci's syndrome

We report a new case of skull base chondrosarcoma in Maffucci's syndrome. Maffucci's syndrome combining enchondromatosis with cutaneous haemangioma is rarely associated with chondrosarcoma. The review of literature highlights a small number of this pathological association.

Chondrosarcoma of the skull base: long-term follow-up

OBJECTIVE

Chondrosarcoma of the skull base is an uncommon neoplasm comprising 0.15% of all intracranial tumors and 6% of skull base neoplasms. The outcome of treatment is difficult to assess because the slow growth rate means that there is a long interval before detecting the recurrence. We describe the use of lateral skull base techniques for these lesions and examine the long-term outcomes. The pathological features, radiological findings, and radiotherapy options are also discussed.

STUDY DESIGN

Retrospective case review with current follow-up where possible.

SETTING

Tertiary referral neurotologic private practice.

PATIENTS

Eight patients with histologically confirmed skull base chondrosarcoma operated on since 1979. At the time of the surgery, the five women and three men ranged in age from 31 to 63 years, with a mean of 42.9 years. The follow-up ranged from 9 months to 25 years and 5 months.

INTERVENTIONS

All patients underwent surgical removal; the earliest patient underwent surgical removal via transcochlear and retrosigmoid approaches, and seven via an infratemporal fossa approach, with or without exenteration of the otic capsule.

MAIN OUTCOME MEASURES

Number of patients with residual and recurrent tumors.

RESULTS

In the patient who underwent surgery via the transcochlear approach, recurrence was noted within 3 months, and new exploration using the retrosigmoid approach was performed for the removal of the recurrent lesion. This patient showed no signs of recurrence for 25 years since last surgery. Of the seven patients who underwent surgery via the infratemporal fossa approach, one had residual tumor found at 1 year, but remained alive and well for 21 years after the surgery. The other six had gross total resection and showed no signs of recurrence at the last known follow-up. One patient died as a result of an unrelated cause 18 years after surgery for the chondrosarcoma.

CONCLUSION

The gross total resection of these lesions is possible because of the evolution of lateral skull base techniques and can be routinely accomplished with the infratemporal fossa approach. The improved exposure afforded by this approach seems to have resulted in more complete extirpation of the tumor and a decrease in the recurrence rate.

Treatment of Multiple Oral and Oropharyngeal Venous Malformations in Maffucci's Syndrome with a Combination of Percutaneous Sclerotherapy and Ligation

Maffucci's Syndrome is an osteochondromatous syndrome with congenital vascular malformations. Major ailments involved are habitual fractures, length discrepancy of the extremities, impediment of the affected parts, extremity overgrowth and pain. The vascular lesions, aside from their mass effects, tend to ulcerate and bleed. Endotracheal intubation is also troublesome in these patients. Malignant tranformation of mesodermal tissue is the major lethal factor in this syndrome. This report describes severe respiratory impairment caused by venous malformations in a young girl. Multiple bunched venous malformations within the tongue, oral cavity and oropharynx were treated with percutaneous sclerotherapy and a simple ligation technique. Airway obstruction was cleared following repetitive treatment sessions.

Maffucci' s syndrome complicated by intracranial chondrosarcoma: two new illustrative cases

Maffucci's syndrome is a rare congenital condition, sometimes misdiagnosed as Ollier's disease, characterized by multiple enchondromas combined with hemangiomas and phlebectasia. Coexisting primary malignancies have been described sporadically. We report two cases of Maffucci's syndrome associated with cranial base chondrosarcoma, emphasizing pathophysiological features and the challenging management of intracranial chondrosarcomas. To the best of our knowledge, only twelve similar cases have been reported in the literature.

Chordomas of the base of the skull and upper cervical spine. One hundred patients irradiated by a 3D conformal technique combining photon and proton beams

To define the prognostic factors for local control and overall survival among 100 consecutive patients with chordoma of the base of skull or upper cervical spine treated by fractionated irradiation combining proton and photon beams. Between December 1993 and August 2002, 100 patients (median age: 53 years [8 - 85], M/F sex ratio: 3/2) were treated by a combination of high-energy photons and protons. The proton component was delivered at the Centre de Protonthérapie d'Orsay (CPO) by a 201 MeV beam. The median total dose delivered to the tumor volume was 67 GyECo. With a median follow-up of 31 months [range: 0 - 87], 25 tumours relapsed locally. The 2- and 4-year local control rates were 86.3% (+/-3.9%) and 53.8% (+/-7.5%), respectively. According to multivariate analysis, at least 95% of the tumor volume encompassed by the 95% isodose (p = 0.048; RR: 3.4 95%CI [1.01 - 11.8]) and a minimal dose delivered into the tumor volume <56 GyECo (p = 0.042; RR: 2.3 95%CI [1.03 - 5.2]) were independent prognostic factors of local control. Ten patients died. The 2- and 5-year overall survival rates were 94.3% (+/-2.5%) and 80.5% (+/-7.2%), respectively. According to multivariate analysis, local tumor control (p = 0.005; RR: 21 95%CI [2.2 - 200]) was a prognostic factor of overall survival. For chordomas of the base of the skull and upper cervical spine treated by surgery and irradiation combining photons and protons, the quality of irradiation, reflected by homogeneity of the dose into the tumor volume, is a major factor of local control. Close attention must be paid to minimize the underdosed areas close to critical organs. The role of surgical resection remains paramount, and a trial of dose escalation would have to consider an increase in the dose to critical organs, especially as current results indicate the low toxicity of this treatment.