Sequence analysis of the rat Brca1 homolog and its promoter region

OBJECTIVE: Isolated malleus-handle fracture is a clinical entity seldom reported in the medical literature but well known in the last century. The purpose of this paper was to review the literature over the last 150 years and describe three new cases. STUDY DESIGN: Extensive review of the literature and chart review of three patients with isolated malleus-handle fracture. SETTING: The study was performed partly at a private practice and partly in an academic tertiary referral center. PATIENTS: At least 43 malleus-handle fractures have been reported in the literature. Three new occurrences were studied. RESULTS: The review of the literature showed that head trauma with skull base fracture was the most frequent cause of malleus-handle fracture, followed by blows on the tympanic membrane and barotrauma, penetration of pen-holders or hair pins, penetration of twigs, and attempts to remove a foreign body pushed inside the ear. In the first patient reported here, the malleus-handle fracture was caused by a whirlpool bath, in the second, the cause was unknown, and, in the third, it was caused by a brisk decompression inside the ear canal. CONCLUSIONS: This lesion is not rare, and the diagnosis frequently is missed because the tympanic membrane appears intact. A careful otoscopic examination with pneumomassage, an abnormally high compliance at tympanometry, and a carefully recorded medical history may lead to the diagnosis of isolated malleus-handle fracture in a patient with a mild conductive hearing loss.     

Effects of Trp64Arg mutation in the beta 3-adrenergic receptor gene on body fat, plasma glucose level, lipid profile, insulin secretion and action in Chinese

A case of concurrent enchondroma and periosteal chondroma of the right proximal humerus in a 19-year-old woman is reported. Radiographs and CT scans showed a periosteal lesion with saucerization and spicula-like mineralization of the lateral aspect of the right proximal humerus and an ill-defined irregular lucency with stippled calcifications of the medullary cavity adjacent to it. MRI showed a long intramedullary lesion in addition to the surface lesion. There was no cortical disruption by imaging and gross examination. Histologically, both lesions showed benign cartilaginous tumors; concurrent enchondroma and periosteal chondroma of the humerus was therefore diagnosed. This combination in the same bone in a patient without enchondromatosis is exceedingly rare. Radiographic features may be confused with chondrosarcoma.     

Surgical management of patients with osteogenesis imperfecta: 10 years'' experience

INTRODUCTION: Chondromas are rare intracranial tumors. The authors present two cases of intracranial intradural chondroma, one originating from the falx cerebri and the other from the dura mater of the convexity. METHOD AND RESULTS: Diagnostic procedures, including magnetic resonance imaging, and surgical findings are described. In both cases, pre-operative diagnosis could have been at least suspected, and the tumor was completely removed, without recurrence after a follow-up of many years. The pathogenesis and pathological findings are discussed, and cases from the literature are reviewed. CONCLUSION: Benign intradural chondroma has a good prognosis, with no recurrence after surgical excision in most cases.     

Nasal cerebral heterotopic tissue (nasal glioma) in the adult: a rare cause of primary cerebrospinal fluid rhinorrhea

BACKGROUND: Nasal cerebral heterotopia is a congenital lesion that is mainly detected in early childhood. The rare cases of this disorder found in adult patients are located intranasally. A common symptom is compromised nasal air passage. Clinical findings include polypoid masses in either the nasal cavity or the paranasal sinuses. To our knowledge, primary cerebrospinal fluid (CSF) rhinorrhea has been reported only twice in these patients. PATIENT: A 64-year-old female patient presented with CSF rhinorrhea proven by beta 2-transferrin testing. Previous head injury or intranasal manipulation were excluded. Anterior rhinoscopy revealed a watery drainage from the right middle meatus. CT scan showed a defect in the lateral roof of the right ethmoid sinus, approximately 5 mm in diameter; MRI revealed a mass in the right ethmoid and frontal sinuses, penetrating the anterior skull base. The lesion was resected by an extranasal approach. It showed a fibrous connection to the frontal lobe. Histologically, the lesion consisted of neural tissue composed of gray and white matter, both with a normal structuring. Dura and skull base were reconstructed. There were no signs of a CSF leak postoperatively. RESULTS AND CONCLUSIONS: The differential diagnosis of CSF rhinorrhea includes traumatic events and neoplasms, elevated intracranial pressure, and connate lesions as encephaloceles and, in rare cases, nasal cerebral heterotopia.     

Non-Hodgkin lymphoma of the central skull base: MR manifestations

OBJECTIVE: The aim of this study was to demonstrate the MR characteristics of non-Hodgkin lymphoma of the skull base to help in the differential diagnosis of this neoplasm from other conditions. MATERIALS AND METHODS: MR of five patients, 7-64 years old, with pathologically proved lymphomas of the skull base were reviewed. Three cases had primary skull base lesions involving the sphenoid bone and the cavernous sinus. One case with a nasal cavity lesion involving the skull base and one with a relapsing skull base lesion of previously treated tonsillar lymphoma were included. RESULTS: The lesions had signal intensities that were similar to that of gray matter of brain on both T1- and T2-weighted imaging. Bilateral cavernous sinuses were involved with encasement of internal carotid arteries in every case. Postcontrast MR showed homogeneous enhancement of the tumor with dural infiltration along the planum sphenoidale, clivus, or tentorium. The clivus was destroyed or replaced by tumors in adult cases but in two children the clivus was preserved with intact sphenooccipital synchondrosis. In one case the tumor extended to the extracranial portion through the jugular foramen. CONCLUSION: The MR findings of a permeative lesion of the skull base, invasion of the cavernous sinus without arterial narrowing, infiltration along the dural surface, and an iso- or hypointensity with brain on T2-weighted imaging should suggest lymphoma.     

The role of stereotactic radiosurgery in the treatment of malignant skull base tumors

PURPOSE: To determine the efficacy and toxicity of stereotactic radiosurgery in the treatment of malignant skull base tumors. METHODS AND MATERIALS: Thirty-two patients with 35 newly diagnosed or recurrent malignant skull base tumors < or = 33.5 cm3 were treated using the Leksell Gamma unit. Tumor histologies included: adenoid cystic carcinoma [12], basal cell carcinoma [1], chondrosarcoma [1], chordoma [8], nasopharyngeal carcinoma [3], osteogenic sarcoma [2], and squamous cell carcinoma [8]. RESULTS: After a median follow-up of 2.3 years, 83% +/- 15% (+/-95% confidence interval) of patients experienced a symptomatic response to treatment. Local control at the skull base was 95 +/- 9% at 2 years and 78 +/- 23% at 3 years. Local-regional control above the clavicles was 75 +/- 15% at 1 year and 51 +/- 20% at 2 years. Overall and cause specific survival were identical, 82 +/- 13% at 1 year, 76 +/- 14% at 2 years, and 72 +/- 16% at 3 years. One patient developed a radiation-induced optic neuropathy 12 months after radiosurgery. CONCLUSION: Stereotactic radiosurgery using the Leksell Gamma Unit can provide durable tumor control and symptomatic relief with acceptable toxicity in the majority of patients with malignant tumors 4 cm or less in size involving the skull base. Further evaluation of more patients with longer follow-up is warranted.     

Low-grade myxoid chondrosarcoma of the temporal bone: differential diagnosis and report of two cases

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.     

Expression of the novel mitoxantrone resistance associated gene MXR7 in colorectal malignancies

Chondrosarcoma constitutes 6% of all primary bone tumors and 11% of malignant primary bone tumors. Nevertheless, in a review of the tumor registry of the University of Michigan covering a period of 50 years, there were only 3 cases involving the temporal bone. A case of a woman with a chondrosarcoma of the temporal bone that was partially resected by means of an infratemporal approach at the skull base is presented. This patient had previously undergone surgical treatment for otosclerosis of the other ear. Several considerations regarding survival factors in this type of tumor are dealt with in terms of the histological features, therapeutic options and anatomic location. The possibility that this lesion may originate from the persistence of the cartilaginous inclusions that some authors consider to be involved in the origin of otosclerosis is discussed.     

Chordomas of the skull base: dynamic MRI

OBJECTIVE: To investigate the role of dynamic MRI in the diagnosis of chordomas at the skull base. MATERIALS AND METHODS: Six patients with surgically proven chordomas of the skull base were examined with spin-echo technique (repetition time/echo time 200 ms/15 ms). Serial imaging was performed every 30 s for 240 s after a rapid injection of gadopenetate dimeglumine (0.1 mmol/kg). The contrast material enhancement ratio (CER) was analyzed. The CER was obtained for each region of interest as follows (Sn - So) x 100/Smax - So, where Sn indicates signal intensity at each dynamic phase; So, signal intensity on the image obtained before administration of contrast material; and Smax, maximum signal intensity of all dynamic imaging. RESULTS: All chordomas showed very slow but steady increase of contrast enhancement with no peak within 240 s. The CERs of six cases at 30 s are 13 to 40 (mean value +/- standard deviation: 22.8 +/- 10.2). CONCLUSION: Dynamic MRI may be helpful in differentiating between chordomas and other tumors of the skull base.     

Longitudinal research using computerized clinical databases: caveats and constraints

Synovial chondromatosis of the temporomandibular joint is a rare occurrence. Resorption of the floor of the skull base caused by the tumour with invasion into the middle cranial fossa has only been described a few times. We report on diagnosis, histologic examination and therapy of a patient with synovial chondromatosis in the articular tubercle of the right temporomandibular joint invading the middle and cranial fossa. After tumour exstirpation the defect in the floor of the middle cranial fossa was reconstructed using a split-skull graft via an intracranial approach.     

Lung abscess complicating chondromas in Carney's syndrome

Carney's syndrome consists of a combination of three rare tumours: gastric leiomyosarcoma, pulmonary chondroma and catecholamine-secreting paraganglioma. We describe a young woman with Carney's syndrome, who developed a lung abscess, due to obstruction of a bronchus by a chondroma, 11 yrs after having had a partial gastrectomy for a leiomyosarcoma.     

Surgery of the base of the skull

To treat pathological processes, primarily tumors, in the base of the skull is one of the most intricate neurosurgical problems. In the past decade, interest in this problem has greatly increased due to the advent of new methods of diagnosis, up-to-date neurosurgical equipment and to a greater cooperation of physicians of related disciplines: ophthalmologists, otosurgeons, plastic surgeons. The authors present and summarize the experience accumulated by the researchers of the N. N. Burdenko Institute of Neurosurgery in the past 10 years in treating basal tumors. Based on a great deal of clinical findings, approaches are proposed in treating some groups of basal tumors, such and pituitary adenomas, craniopharyngiomas, meningiomas at various sites, trigeminal and acoustic neurinomas, and malignant neoplasms of the base of the skull. The conditions required for successful surgical treatment of the processes in the base of the skull are described in detail. One of them is a correct determination of a surgical approach.     

Extraskeletal chondroma of the foot

Extraskeletal chondroma is a rare, benign cartilaginous tumor seen most frequently in the soft tissues of the hands and feet. The authors present a case of extraskeletal chondroma in a 52-year-old male patient who had a small mass on the left foot involving the flexor surface of the second toe. Radiographs showed the presence of a soft-tissue mass with scattered calcified foci. Surgical excision revealed a benign, lobulated cartilaginous tumor with prominent areas of calcification. Histologically; the lesion consisted of cartilage cells with centralized zones of cellular pleomorphism and giant-cell proliferation at the tumor margin consistent with extraskeletal chondroma.     

Neurotrophic factor and neuronal apoptosis]

We document the occurrence of a solitary extramedullary plasmacytoma (SEP) in a cardiac transplant patient. The diagnosis of plasma cell malignancy was confirmed by histopathologic and immunohistochemical examination of a nodular skin lesion. A complete systemic evaluation showed no evidence of metastatic disease. The patient was treated locally with radiation therapy (RT), but disseminated multiple myeloma developed 4 months after diagnosis. A variety of tumors have been reported to develop in the cardiac or renal transplant recipient, although plasma cell malignancies are rare. To our knowledge, this is the first reported case of an SEP in an organ transplant recipient.     

Experiences with hemangiopericytoma in cranial base surgery

BACKGROUND: Haemangiopericytomas are rare vascular neoplasms which show either slow local tumour growth or aggressive progression in size with a high tendency of recurrence and metastasis. Manifestations of haemangiopericytomas in the area of the nose and sinuses are supposed to have a relatively benign course. To date clinical and histological parameters for prognosis are uncertain. Therefore in a quite large number of cases only the clinical course allows to evaluate the dignity of a haemangiopericytoma. PATIENTS AND RESULTS: We present our experience with five haemanglopericytomas in contact with the skull base out of a total number of 457 skull base tumours. The site of origin of these five haemangiopericytomas were: nasal septum, pterygopalatine fossa, oronasopharynx, temporal bone, and parotid gland. All neoplasms showed primary or recurrent tumor in contact with the skull base and an intracranial extension was observed twice. One patient died postoperatively of a cerebral infarction. Three patients showed one or more recurrences which were treated surgically. In one case 5 recurrences occurred. Despite of 4 surgical procedures within a period of 15 months, the tumour could be controlled only for a short period of time, and the patient died 16 months after the first operation. CONCLUSION: One has to consider that haemangiopericytomas of the head and neck show a potential malignant course. The vascular tumor may recur decades later. Adequate therapy and life-long follow-up are therefore mandatory in haemangiopericytomas. Complete surgical resection of the tumour is usually the treatment of choice, in spite of the high degree of surgical skill required, especially in advanced tumour and in case of recurrence.     

Indications for, contraindications to, and interruption of craniofacial procedures

In spite of increasing experience with skull base surgery, some of the guidelines for indications for operations may vary according to the institution. One-hundred two patients underwent craniofacial oncologic resections at our institution from 1982 to 1995. A retrospective analysis of the indications for and contraindications to these procedures was undertaken. The main indications for malignant tumors were skin lesions with direct invasion of the anterior or lateral skull base (69%) and nasal-paranasal sinus tumors (21%). The main indications for benign tumors were glomus lesions (26%), menigiomas (22%), and fibro-osseous lesions of the anterior skull base (19%). The main contraindications were extensive invasion of the central nervous system, invasion of the cavernous sinus and/or internal carotid artery by aggressive malignancies, and bilateral orbital invasion in a nonblind patient. Also, 6 patients had their procedures interrupted during craniotomy for several reasons - extensive central nervous system invasion (2 cases), bilateral orbital invasion (1), lack of brain retraction (1), lack of histologic diagnosis during the operation (1), and purulent discharge at the frontal sinus (1). Craniofacial oncologic operations are extensive surgical procedures that have to be properly indicated in order to obtain low levels of morbidity and mortality. The selection of cases is of paramount importance. In some instances, it seems advisable even to interrupt these operations in the first phase.     

Model-based surgical planning and simulation of cranial base surgery

Plastic skull models of seven individual patients were fabricated by stereolithography from three-dimensional data based on computed tomography bone images. Skull models were utilized for neurosurgical planning and simulation in the seven patients with cranial base lesions that were difficult to remove. Surgical approaches and areas of craniotomy were evaluated using the fabricated skull models. In preoperative simulations, hand-made models of the tumors, major vessels and nerves were placed in the skull models. Step-by-step simulation of surgical procedures was performed using actual surgical tools. The advantages of using skull models to plan and simulate cranial base surgery include a better understanding of anatomic relationships, preoperative evaluation of the proposed procedure, increased understanding by the patient and family, and improved educational experiences for residents and other medical staff. The disadvantages of using skull models include the time and cost of making the models. The skull models provide a more realistic tool that is easier to handle than computer-graphic images. Surgical simulation using models facilitates difficult cranial base surgery and may help reduce surgical complications.     

Vagal paraganglioma: a review of 46 patients treated during a 20-year period

BACKGROUND: Vagal paragangliomas (VPs) arise from paraganglia associated with the vagus nerve. Approximately 200 cases have been reported in the medical literature. Because of their rarity, most information regarding these tumors has arisen from case reports and small clinical series. OBJECTIVE: To detail the clinicopathologic features of 46 patients with VP with an emphasis on the role of a multidisciplinary skull base team in both the successful extirpation and rehabilitation. DESIGN: Retrospective review of 46 patients with VP managed by a single skull base team. SETTING: An academic tertiary medical center. RESULTS: Forty-six patients were treated over a 20-year period (1978-1998). Ten (22%) demonstrated intracranial extension. There was a history of familial paragangliomas in 9 (20%) of the patients. The incidence of multicentric paragangliomas was 78% in patients with familial paragangliomas vs 23% in patients with nonfamilial paragangliomas. Management of this group of 46 patients consisted of surgery (n = 40), radiation therapy (n = 4), and observation (n = 2). The operative approach consisted of a transcervical excision often combined with a transtemporal or lateral skull base approach as dictated by the tumor extent. Postoperative cranial nerve deficits were common, and, as such, aggressive rehabilitation was a vital component in the management of these tumors. CONCLUSIONS: The management of VP and its associated cranial nerve deficits remains a difficult clinical problem. Options for treatment include surgical resection, radiation therapy, and, in selected cases, observation. Surgical extirpation requires a multidisciplinary skull base team to achieve complete tumor resection. Radiation therapy is reserved for elderly patients and patients at risk for bilateral cranial nerve deficits. Rehabilitation of cranial nerve deficits is an integral part of the management of VP.     

Aggressive fibromatosis (fibrosarcoma) of the facial nerve

Aggressive fibromatosis of the facial nerve is a very rare tumor. Three cases have been previously reported. The tumor is locally recurrent and often has a fatal outcome. This report is of a ten-year-old boy whose tumor originally developed in the parotid area with subsequent spread to the base of the skull, the neck and the cerebellopontine angle. Treatment was by wide surgical excision, radiation therapy and chemotherapy. Despite treatment, the patient died. The clinical features of this case will be described. Only wide surgical excision early in the course of the disease may offer a chance for cure.