Intracranial tumours in the first year of life

Summary Twenty-five infants with histologically verified brain tumours presenting during the first year of life and diagnosed by computed tomography (CT) were studied. The clinical features are presented, the results of surgery assessed and the CT findings analysed and compared with the macroscopic appearance of the tumours. Since the introduction of CT, the number of intracranial tumours diagnosed in infancy has increased, particularly in the supratentorial location. In our study, astrocytomas were the most common, followed by choroid plexus papillomas, ependymomas and primitive glial tumours. At diagnosis, many tumours had become large, but usually had a well-defined edge, suggesting expansion rather than infiltration. The CT features generally corresponded to the macroscopic appearance of the tumours. The operative mortality in the series was 20%.     

Comparison of sonography of the soft tissues of the neck with computerized tomography and magnetic resonance

Ultrasound B-scan, computed tomography and magnetic resonance imaging are currently used in the diagnosis of head and neck tumours. Screening of head and neck tumours should be performed by high resolution B-scan. Its high diagnostic sensitivity, minimal imaging artifacts, real-time recording and its minimal costs are outstanding features. CT is superior in imaging of bony structures; on the other hand, MR is superior in demonstrating site, border and topography of tumours and lymph nodes. Postoperative and/or post-irradiation follow-up of head and neck tumours should be done by sonography which allows differentiation of oedema, scars and tumour recurrence. The parapharyngoscopic sonography, echography, CT and MR can deliver different aspects in planning of neck surgery. An adequate diagnostic schedule is presented.     

Soft tissue tumours and mass-like lesions of the chest wall: a pictorial review of CT and MR findings

Soft tissue tumours and tumour-like lesions of the chest wall are uncommon. The purpose of this pictorial essay is to describe the imaging findings of chest wall soft tissue tumours and tumour-like lesions. We searched the radiological and pathological archive at our institution retrospectively and reviewed the literature on soft tissue tumours of the chest wall. Common chest wall soft tissue tumours and mass-like lesions include peripheral nerve tumours, lipomas, liposarcomas, haemangiomas, elastofibromas, metastases, lymphoma and abscesses. Other lesions encountered include desmoid tumours and malignant fibrous histiocytoma. Many have distinctive radiological findings or occur in specific locations, allowing a specific radiological diagnosis to be suggested.     

Primary tumors of the diaphragm. Apropos of a case

The diagnosis of diaphragmatic tumours is complicated by their rarity and because they are often difficult to distinguish from the more frequent tumours of surrounding structures. We describe two cases: an invasive fibroma and a primary hydatid cyst. We discuss the differential diagnosis of diaphragmatic tumours and suggest a systematic approach to their radiological diagnosis, stressing the value of ultrasonography, CT scanning and diagnostic pneumoperitoneum.     

Surface lesions of the bones of the hand

Surface lesions involving the bones of the hand are uncommon. This pictorial review illustrates the spectrum of conditions including benign primary bone tumours, malignant primary bone tumours and non-neoplastic disorders. The review focuses on the radiographic appearances of these lesions and other techniques such as CT and MR imaging that may suggest a specific diagnosis.     

Brain stem auditory evoked potentials in various tumors in the cerebellopontine angle

Abnormalities of brainstem auditory evoked potentials of 63 patients with tumours in the pontocerebellar angle were classified in 7 types and correlated by size and nature of tumours. Types A and B brainstem responses are characteristic for small tumours up 20 mm and are indicated for computed pneumocysternography in spite of the negative CT of the brain. Type C is statistically more frequently found than larger tumours over 22 mm in size. Other types of responses which are more characteristic for tumours which are not neurinomas are described. Auditory evoked potentials are the most reliable neuro-otologic methods in detection of PCU tumours and their careful analysis provides valuable data both about the size and nature of tumours.     

Malignant chondroid syringoma of the skin: magnetic resonance imaging features

Skin tumours are usually divided into melanoma and non-melanoma types. Malignancies of the adnexal structures, of which sweat gland tumours are an example, are characterized under the non-melanoma types. Sweat gland malignancies are rare tumours that are usually associated with a poor prognosis. Given the rarity of these tumours, MRI findings of such tumours have not been described previously in the literature. We present a case report of an unusual malignant tumour of sweat gland origin known as a malignant chondroid syringoma of the skin with described MRI features. The MRI features are non-specific depicting intermediate signal intensity, changes on the proton density sequence and increased signal on the T2 and STIR-weighted sequences. Although these imaging features are characteristic of most soft tissue masses MRI can, in most cases, accurately depict the anatomic extent and identify tissue of origin, depth of invasion and relation to adjacent structures, such as muscles and bones. Thus high-resolution MRI of the skin in the future can be extremely helpful in characterizing and staging dermal neoplasms.     

Epidermoid cyst of the base of the skull]

Epidermoid cysts are rare congenital tumours representing less than 1% of all intracranial tumours. They are derived from the development of abnormally situated ectodermal tissue and are often an incidental finding. We report a case confined to the base of the skull, responsible for an extradural mass.     

Carcinoid tumour of the orbital muscles: A rare occurrence

Malignant carcinoid tumours are rare and usually follow an indolent course. Metastases from these tumours are uncommon, and usually involve bone, liver and lymph nodes. Orbital metastases have rarely been described, and generally involve the choroid rather than orbital structures. Our knowledge of the response of these tumours to radiotherapy is extremely limited. Two cases of orbital metastases treated with radiotherapy are presented here and the literature on the efficacy of palliative radiotherapy for this tumour is reviewed. Recommendations are made regarding an effective radiotherapy regimen for treating orbital metastases from malignant carcinoid tumours.     

MRI of cartilaginous tumours of the larynx.

Cartilaginous lesions of the larynx are uncommon, approximately 250 cases being documented in the literature. In general, these tumours grow slowly, exhibiting only local aggressiveness. Distant metastases are rare. Up until now CT has been the best diagnostic tool for the evaluation of these tumours because it demonstrates intratumoral calcification so well. To the best of our knowledge there are no reports of the use of MRI for these lesions. Three cases of cartilaginous laryngeal tumours are presented, emphasizing the MRI features.     

Radiotherapy of giant-cell tumour of the vertebral column (author's transl)]

Five cases of successfully irradiated giant-cell tumours of the backbone, are reported; the problems of the radiotherapy of such tumours are discussed.     

Petrous surgical approaches in tumors of the cerebellopontine angle]

Three petrous incisions, performed by an ENT-neurosurgery team, can be used for the resection of tumours of the cerebellopontine angle: transpetrosal incisions (posterior translabyrinthine and transcochlear) which provide large access to the IAM and the posterior surface of the petrous bone, but they sacrifice hearing. The suprapetrosal incision (reserved for tumours in the meatus) and the mastoidoretrosigmoid incision (for tumours less than or equal to 20 mm) preserve the labyrinth in an attempt to preserve hearing. The principal objectives of surgical resection of tumours of the cerebellopontine angle (85% of which are acoustic neuromas) are total resection (to preserve the vital prognosis) and preservation of facial nerve function. Attempts to preserve hearing must be confined to cases selected by a complete clinical otological and audiometric examination.     

Rare tumors of the cerebellopontine angle]

Tumours of the cerebellopontine angle are essentially benign in adults, are generally treated surgically and require a preoperative assessment as precise as possible. MRI simplifies the diagnostic assessment; it is indicated as the first-line investigation and is usually sufficient whenever a tumour of the posterior cranial fossa is suspected. Acoustic neuromas represent 75% of all tumours of the cerebellopontine angle. Other tumours are rare and essentially consist of meningioma, detected in 10 to 14% of cases and cholesteatoma in 1 to 5% of cases. Cholesteatoma, with a pathognomonic appearance, must be distinguished from arachnoid cyst. Other tumours are exceptional. The authors define the diagnostic criteria based on their experience and present a recent review of the literature.     

Squamous epithelial carcinoma and undifferentiated carcinoma of the inner nose and paranasal sinuses

272 patients with tumours of the nasal cavity and paranasal sinuses were followed up from 1949 until 1982 at the ENT Department of the University Hospital in Kiel. 53% of the tumours were classified as squamous cell or undifferentiated carcinomata. At an early stage such tumours cause nonspecific symptoms which may mimic those of chronic sinusitis. Early diagnosis is usually hindered by the occult growth within the facial skeleton and especially by the minor symptoms caused by tumours of the paranasal sinuses. In contrast, tumours of the nasal cavity cause symptoms at an early stage and consequently are diagnosed early. The majority of cases with tumours of the paranasal sinuses present at an advanced stage (T3 to T4) in 70% of cases. The most common site of squamous cell carcinoma is the maxillary sinus (50%). Distant metastases and regional lymph node metastases are rarely seen at presentation regardless of the size of the primary tumour. Metastases usually indicate a tumour dependent death in the near future. The main prognostic indicators are the size of the tumour (significantly worse prognosis for T4 in comparison to T2 or T3 tumours) and the localisation (significantly better prognosis for tumours of the floor of the nasal cavity or the nasal septum compared to tumours of the paranasal sinuses). The age of the patient or the degree of differentiation of the tumour did not influence on the survival rate. Tumour-dependent deaths rarely occur after more than five years. Patients were assigned to two treatment groups and matched according to the tumour stage. One group received surgery only, whereas the second group received a combined treatment of surgery with subsequent radiotherapy. There was a significant difference between the two groups in favour of the surgical treatment. According to these data we recommend surgical excision without postoperative irradiation in cases where complete removal of the tumor has been histologically proven.     

Radionuclide imaging of neuroendocrine tumours: biological basis and diagnostic results

Neuroendocrine tumours have been defined as APUD-omas in the past by authors who identified common metabolic characteristics (amine precursor uptake and decarboxylation) in a group of tumours thought to originate from cells of the neural crest and to be able to produce biogenic amines. The identification of neuroendocrine tumours with APUD-omas was not confirmed by subsequent investigators. At present it is known that a group of neuroendocrine tumours derive from pluripotent stem cells or from differentiated neuroendocrine cells, and that they have a particular pattern of histology due to the presence of some secretory products and particular cytoplasmic proteins. Many radiopharmaceuticals have been successfully used in nuclear medicine to visualise neuroendocrine tumours; most of them are based on specific uptake mechanisms, but some are non-specific probes. This review is focussed on the clinical application of radiolabelled metaiodobenzylguanidine, indium-111 pentetreotide, radiolabelled vasointestinal peptide, radiolabelled monoclonal antibodies and positron-emitting tracers. While many different types of neuroendocrine tumours are identified today, only the most common histotypes and those tumours of major relevance for nuclear medicine are considered in this review (anterior pituitary tumours and neuroblastoma are excluded). New knowledge in molecular biology, relevant biological and histological patterns, and the physiological and clinical behaviour are described for neuroendocrine tumours of the lung, tumours of the gastroenteropancreatic tract, medullary thyroid carcinoma, tumours of sympatho-adrenal lineage, and multiple endocrine neoplasia. The nuclear medicine results in diagnostic imaging are presented, and the major comparative studies with different tracers are reported. The study of further possible diagnostic approaches addressing the biological characteristics of these tumours could open the way to various new therapeutic options.     

Vascular masses of the head and neck

The classification, clinical presentation, natural history and imaging appearances of vascular masses of the head and neck are reviewed. The radiological appearances of congenital vascular masses (infantile haemangiomas and other congenital vascular tumours, high-flow and low-flow vascular malformations), acquired vascular masses (benign and malignant tumours, non-neoplastic lesions) and other hypervascular masses are described and illustrated, together with consideration of image-guided interventions.     

Neuroradiological findings of intracranial schwannomas not arising from the stems of cranial nerves

Four cases of intracranial schwannomas not arising from the stems of cranial nerves are reported. All cases were confirmed by surgery and pathological examination. The related histogenesis and the CT and MRI findings are discussed, and the literature is reviewed. The CT and MRI findings of these tumours were analysed retrospectively and their pathological characteristics were reviewed. The tumours presented as heterogeneous hypointense to isointense mixed dense lesions with multiple areas of cystic degeneration and necrosis. Extensive cystic degeneration was the prominent characteristic on CT. The tumours showed hypointense to isointense signal on T(1) weighted images and heterogeneous hyperintense signal on T(2) weighted images. On contrast enhanced CT and MRI, the solid component and the wall of the tumours showed moderate to strong enhancement. Haematoxylin and eosin staining of the lesion demonstrated two histological patterns, Antoni type A and Antoni type B. Immunostaining showed intense immunoreactivity for S-100 protein. The CT and MRI findings of these tumours were similar to those of schwannomas arising from cranial nerves, although the former show a higher rate of cystic degeneration. Therefore, even when a mass is not in the usual cranial nerve region, if its imaging characteristics are similar to those of common schwannomas, the possibility of a schwannoma not arising from cranial nerve should be considered.     

Mesenchymal tumours of the thorax: CT findings and pathological features

Mesenchymal tumours of the thorax are uncommon and may originate from the muscle, bone, cartilage, vessel, nerves, fat and fibrous tissue. These tumours occur at different sites including the lung, pleura, mediastinum or chest wall. Mesenchymal tumours tend to show protean and non-specific imaging characteristics. However, in some instances, the imaging characteristics of the tumour may allow a specific diagnosis to be made, such as with lipoid or vascular tumours.     

201Tl SPET in the differential diagnosis of brain tumours.

The aims of this study were to assess the utility of 201Tl single photon emission tomography (SPET) in the differential diagnosis of brain tumours and to elucidate the relationship between 201Tl tumour uptake and degree of contrast-enhancement on magnetic resonance imaging (MRI). Early (15 min) and delayed (3 h) 201Tl SPET imaging and T1-weighted MRI were performed before and after Gd-DTPA enhancement in 101 (41 malignant and 60 benign) untreated brain tumours. The 201Tl uptake ratio (tumour-to-normal brain count ratio) for both the early and delayed SPET studies and the retention index (the ratio of delayed to early 201Tl uptake) were calculated. Malignant tumours were separated from benign tumours with 87% accuracy based on the assumption that tumours with a 201Tl retention index < 0.7 or no abnormal uptake are benign. Meningiomas and pituitary adenomas were differentiated from other benign tumours by their characteristic pattern on SPET. The degree of contrast-enhancement of the tumour on MRI was concordant with the early 201Tl uptake ratio for most histological types. However, schwannomas and cavernous haemangiomas showed a low 201Tl uptake ratio in spite of a high degree of contrast-enhancement on MRI. In conclusion, 201Tl SPET provides additional information that helps in the differential diagnosis of brain tumours.     

PET/CT appearance of desmoid tumour of the chest wall

Desmoid tumours are rare, poorly circumscribed tumours that have a firm consistency and, although benign, have a remarkable tendency to infiltrate into surrounding structures. Extra-abdominal desmoid tumours involve mainly the extremities or the chest wall and are usually managed by wide radical resection. Moreover, desmoid tumours involving the chest wall are locally aggressive tumours with a high recurrence rate. We report a case of a pathologically proven desmoid tumour of the chest wall in a patient with a history of bilateral breast cancer and oesophageal cancer. We discuss the imaging appearances of this tumour on positron emission tomography combined with computed tomography (PET/CT) and magnetic resonance imaging.Desmoid tumours are poorly circumscribed tumours that are firm, rubbery and have a remarkable tendency to infiltrate into surrounding structures with a strong propensity to recur locally after resection [1]. Desmoid tumours of the chest wall are uncommon tumours that have been described extensively in the pathological and surgical literature.¹⁸F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography combined with computed tomography (FDG-PET/CT) has been shown to be very useful in the staging of patients with breast cancer and oesophageal cancer, as well as in the evaluation of treatment response [2]. It has a specific ability to discriminate responders from non-responders more accurately and earlier than conventional imaging methods [2]. PET/CT also plays an important role in the assessment of malignant soft-tissue tumours of the chest wall, such as sarcoma, by improving the accuracy of staging and helping to determine the appropriate therapy [3]. The PET/CT imaging characteristics of chest wall desmoid fibromatosis, a benign condition that may clinically mimic metastatic disease or sarcomatous degeneration, has not yet been reported to our knowledge.We describe the PET/CT and MRI appearances of a biopsy-proven desmoid tumour of the chest wall in a patient with a history of bilateral breast cancer and oesophageal cancer.