Congenital reticulum cell sarcoma of the cerebellum

Summary A case report, with autopsy findings, of a large circumscribed reticulum cell sarcoma of the cerebellum, in a 15 day-old female infant with clinical symptoms from the 8th day of life, and a review in tabular form of histologically confirmed primary intracranial sarcomas during the first year of life are presented. Among 200 intracranial tumours (except for teratomas) in infants up to one year of age, collected from the literature and a personal series of cases, primary sarcomas account for 9,5% and medulloblastomas for 15%. The relationship between cerebellar reticulum cell sarcoma and so-called medulloblastoma is briefly discussed. The aetiology of congenital intracranial neoplasms is unknown.

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Zusammenfassung Fallbericht über ein erst autoptisch verifiziertes großes, umschriebenes Reticulumsarkom des Kleinhirns bei einem 15 Tage alten weiblichen Säugling, der klinisch Symptome ab dem 8. Lebenstag geboten hatte. Eine Übersicht der histologisch gesicherten primären intrakraniellen Sarkome im ersten Lebensjahr wird in tabellarischer Form gegeben. Unter 200 intrakraniellen Geschwülsten — außer Teratomen — bei Neugeborenen und Säuglingen aus dem Weltschrifttum und einer eigenen Beobachtungsserie machen primäre Sarkome 9,5% und Medulloblastome 15% aus. Die Beziehungen zwischen Reticulumsarkom des Kleinhirns und sog. Medulloblastom werden kurz erörters. Die ätiologie angeborener Hirngeschwülste ist unbekannt.

     

Lactate dehydrogenase isoenzymes in tumours of the nervous system

Summary The variations in the isoenzymes of lactic acid dehydrogenase have been studied in a series of tumours of the nervous system. From these the ratio of heart muscle component to skeletal muscle component (the H/M ratio) has been calculated and compared with the H/M ratio of a variety of regions of normal brain. Oligodendrogliomata were found to have a very high H/M ratio. There was a decrease in the ratio with increasing degrees of de-differentiation of all tumours studied. However the H/M ratio does not appear directly related to the rate of growth irrespective of the tissue of origin of the tumour. Tumours derived from different tissues appear to have their own range of ratios. Tumour cyst fluids showed similar ratios to their parent tumours.     

Myogenic tumours of the larynx

Summary The pathology and clinical course of the very rare tumours of the smooth and striated muscles of the larynx are described. The literature is reviewed and personal cases of angioleiomyoma, leiomyosarcomas, rhabdomyoma, and rhabdomyosarcoma are reported.     

Continuing challenges of primary neuroendocrine tumours of the thymus: A concise review

Primary neuroendocrine tumours of the thymus (NETTs) are exceedingly rare tumours, usually presenting around mid-life, which have a propensity towards males and smokers. They are seen more often in those with MEN-1, but multiple different genetic mutations have been found to be involved in the tumorigenesis of NETTs. Histologically, NETTs are classified according to number of mitoses, the presence of necrosis, and the presence or absence of small cell features. NETTs display a wide spectrum of behavior, and they can be incidentally found on chest imaging, on screening in MEN-1, or present with symptoms of local compression. Advanced disease and paraneoplastic syndromes are common. CT-, PET/CT-, MRI-scans, and somatostatin receptor scintigraphy are the imaging modalities of choice both for the initial assessment as well as for monitoring after treatment. For patients with localized disease, complete surgical resection with lymphadenectomy provides the best chance of long-term, disease-free survival, and can be achieved through either an open or thoracoscopic approach. While chemotherapy-regimens based on platinum, taxane, and temozolomide are used most often, the optimum chemotherapy regimen in the adjuvant and palliative settings remains unclear, as does the role of radiotherapy. Ongoing research on the most effective use of somatostatin analogues, peptide receptor radionuclide therapy (PPRT), kinase inhibitors and immunotherapy in patients with other types of advanced neuroendocrine tumours may lead to further treatment options for NETTs in the future.     

Differentiating medulloblastoma in adults

Abstract

We present two cases of medulloblastoma in adult patients showing extensive astrocytic differentiation. In one case, there was synchronous oligodendroglial differentiation, both changes appearing after treatment with radiotherapy. The possible role of radiotherapy in the differentiation is discussed.     

Prediction of carcinogenic potential of chemicals using repeated-dose (13-week) toxicity data

Sub-chronic toxicity studies of 163 non-genotoxic chemicals were evaluated in order to predict the tumour outcome of 24-month rat carcinogenicity studies obtained from the EFSA and ToxRef databases. Hundred eleven of the 148 chemicals that did not induce putative preneoplastic lesions in the sub-chronic study also did not induce tumours in the carcinogenicity study (True Negatives). Cellular hypertrophy appeared to be an unreliable predictor of carcinogenicity. The negative predictivity, the measure of the compounds evaluated that did not show any putative preneoplastic lesion in de sub-chronic studies and were negative in the carcinogenicity studies, was 75%, whereas the sensitivity, a measure of the sub-chronic study to predict a positive carcinogenicity outcome was only 5%. The specificity, the accuracy of the sub-chronic study to correctly identify non-carcinogens was 90%. When the chemicals which induced tumours generally considered not relevant for humans (33 out of 37 False Negatives) are classified as True Negatives, the negative predictivity amounts to 97%. Overall, the results of this retrospective study support the concept that chemicals showing no histopathological risk factors for neoplasia in a sub-chronic study in rats may be considered non-carcinogenic and do not require further testing in a carcinogenicity study.     

Hoffa’s fat pad tumours: What do we know about them?

Purpose

We report on a group of patients with tumours in the Hoffa’s fat pad (HFP), their clinical presentation, histological type and treatment, including two synovial sarcomas with their clinical follow-up, which have not been described previously in the literature.

Methods

We performed a retrospective review of our prospectively collected database of 25 cases of HFP tumours with at least six months follow-up.

Results

The gender, age at presentation (over and under 16 years of age), clinical features, history of trauma, treatment chosen, and complications were recorded. The mean age of the patients was 32 years (three to 47). Six patients were under 16 years old. Pain was the most common symptom, present in 92 % (n = 23/25). The final diagnoses included 23 (92 %) benign tumours and two (8 %) malignant tumours. The most common benign tumour was pigmented villonodular synovitis (PVNS) (48 % n = 12). The two malignant tumours were synovial sarcomas and both presented in patients under 16 years old.

Conclusions

Hoffa’s fat pad tumours are an uncommon and rarely diagnosed group of lesions that can be misinterpreted as any knee pathology. Although the majority of HFP tumours are benign, malignant tumours should be considered in the differential diagnosis for the paediatric population.     

Lumbosacral intradural tumours simulating disc disease

Summary Twelve patients with symptoms and signs simulating lumbar disc disease were found to have intradural tumours in the lumbosacral area. Of the nine patients with a neurofibroma, two had previously had a laminectomy for an erroneous diagnosis of disc herniation and one had three separate tumours which were excised in two successive operations. One of the three patients with an ependymoma had a coccygectomy before the correct diagnosis was made. Only one patient who had an ependymoma showed radiographic abnormalities suggesting a neoplastic lesion, but eight of the ten cases in which the cerebrospinal fluid was analysed had a protein content exceeding 50 mg per 100 ml. Myelography provided the correct diagnosis in all cases. Excision of the tumour resulted in full clinical recovery except for one patient with an ependymoma.

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Résumé Chez douze malades présentant une symptomatologie évocatrice d'une hernie discale lombaire, on a découvert une tumeur intradurale. Des neuf patients porteurs d'un neurofibrome, deux avaient subi auparavant une laminectomie du fait d'une erreur de diagnostic avec une hernie discale et un avait trois tumeurs distinctes dont l'ablation nécessita deux interventions successives. Un des trois malades atteints d'épendymome avait subi une résection du coccyx avant que le diagnostic exact ait été posé. Un seul patient, porteur d'un épendymome, présentait des anomalies radiologiques évocatrices d'une lésion néoplasique, mais huit des dix sujets chez lesquels a été pratiqué l'examen du liquidecéphalo-rachidien avaient une albuminorachie supérieure à 50 mg pour 100 ml. La myélographie a permis un diagnostic correct dans tous les cas. L'éxérèse de la tumeur a toujours permis d'obtenir la guérison complète, sauf chez un malade porteur d'un épendymome.

     

Temperature distribution produced by a cylindrical etched fibre tip in laser treatment of tumours by local hyperthermia

A mathematical model is described for the temperature distribution produced when the optical fibre used in laser treatment of tumours has an etched cylindrical tip. Exact solutions are quoted for the equilibrium temperature distribution, of a form easily evaluated with minimal computing facilities. A number of special cases are worked out to illustrate the shape and size of the region treated for different lengths of the tip and different applied powers. Strongly scattering combinations of tissue and wavelength are considered, as well as an example in which absorption is dominant, and an intermediate case. These calculations can be used to estimate the power necessary, alignment of the fibre, and exposure necessary to treat a given tumour. It is clear from them that an etched fibre has many advantages over a conventional tip, especially the greatly reduced risk of charting of the tissue as the maximum temperature reached for a given power is much lower. Consequently, a larger region can be treated than would be possible with a normal tip. Information obtained in this way can be used to supplement the surgeon's experience when deciding on the appropriate form of treatment.     

Molecular aspects in tumour photochemotherapy

Photochemotherapy is based on the selective retention by tumours of a photosensitizer which can then be inactivated upon local irradiation by visible laser light. The process involves the photosensitized generation of reactive intermediate species, such as singlet oxygen, with deleterious effects on the diseased tissues. Some fundamental aspects relevant to this new method are examined. Emphasis is given to the interactions of photosensitizers with membranes and to directions for the development of more efficient molecules.