Biomedical subjects

C H Rickert

Publications and source records attributed to C H Rickert.

At least 37 records · Page 2Linked to original sources

PubMed2001

High uptake of L-3-[123I]iodo-alpha-methyl tyrosine in pilocytic astrocytomas.

Despite a favourable prognosis, pilocytic astrocytomas may exhibit signs of malignancy on various neuroimaging modalities. This retrospective analysis was conducted to determine whether scintigraphic features of malignancy are also found on single-photon emission tomography (SPET) using L-3-[123I]iodo-alpha-methyl tyrosine (IMT) as a tracer. Twenty patients with pilocytic astrocytomas were retrospectively selected from a large series of patients referred for the evaluation of primary or recurrent brain tumours. IMT SPET was performed in 16 patients, positron emission tomography (PET) using 2-[18F]fluoro-2-deoxy-D-glucose (FDG) was available in 10 of the patients and SPET using technetium-99m tetrofosmin or thallium-201 had been performed in 11. Image analysis was performed using standard protocols to determine how many patients exceeded the respective thresholds of malignancy. Features of malignancy were found in 7/16 IMT SPET studies, in 7/10 FDG PET studies and in 7/11 of the residual SPET investigations. A significant correlation of tumour size and IMT uptake in primary pilocytic astrocytomas indicated partial volume effects to partly account for the differential uptake behaviour (n = 10, r = 0.87, P < 0.05). Differences in IMT uptake in primaries (1.7 +/- 0.6, n = 10) and in recurrent tumours (2.3 +/- 0.7, n = 6) did not attain statistical significance. IMT SPET results indicative of malignancy are regularly found in pilocytic astrocytomas, despite their good prognosis. No uptake may be detected in largely cystic or in small tumours.

Adolescent↗

PubMed2001

Epidemiology of central nervous system tumors in childhood and adolescence based on the new WHO classification.

METHOD: The topography, sex distribution and histology of 340 primary CNS tumors in children up to 17 years of age were investigated and (re-)classified according to the latest WHO classification of nervous system tumors. RESULTS: Overall the prevalence for boys (60.9%) was higher and supratentorial locations predominated (53.3%); there was an even distribution of low-grade WHO I/II (51.5%) and high-grade WHO III/IV (48.5%) tumors. Boys were more commonly affected in all age groups throughout childhood and adolescence. Infratentorial location was more common between the ages of 3 and 11 years (57.5%). High-grade tumors were more frequently encountered up to the age of 5 years (53.2%). The main histological entities were pilocytic astrocytomas (23.5%), followed by medulloblastomas (16.3%), ependymomas (10.1%), anaplastic astrocytomas and glioblastomas (7.2% each), and craniopharyngiomas (5.6%); astrocytomas overall accounted for 47.3% of pediatric brain tumors. Rarer entities included germ cell tumors, gangliogliomas, and meningiomas (2.5% each), supratentorial PNET and pineal parenchymal tumors (1.9% each), atypical teratoid/rhabdoid tumors (1.3%), choroid plexus tumors (0.9%), and desmoplastic infantile astrocytomas and dysembryoplastic neuroepithelial tumors (0.6% each). A meta-analysis of 10,582 childhood brain tumors accumulated from 16 international surveys revealed a male-female ratio of 1.29 and a supra-/infratentorial ratio of 0.92. The most common histological diagnoses were astrocytomas (37.6%), medulloblastomas (17.7%), ependymomas (9.9%), craniopharyngiomas (7.3%), and germ cell tumors (4.4%). CONCLUSIONS: Pediatric brain tumors vary considerably in their histological, topographical and gender distribution throughout childhood and adolescence, reflecting different dynamics of individual tumor entities as well as a susceptibility to their occurrence during certain periods of a child's life. Although at times difficult to characterize, pediatric CNS tumors can be satisfactorily classified according to the latest WHO classification of nervous system tumors.

Adolescent↗

PubMed2001

Rosetted glioneuronal tumor: a case with proliferating neuronal nodules.

Glioneuronal tumors with neuropil-like islands (rosetted glioneuronal tumors) were recently reported as a novel brain tumor entity with characteristic clinicopathological features (Am J Surg Pathol 23: 502, 1999). Here we describe the clinical, histological and genetic features of another case arising in the parietal lobe of a 43-year-old man suffering from focal motor epilepsy. Histologically, nodules of small neuronal tumor cells immunoreactive for synaptophysin and NeuN were embedded within a diffuse astrocytoma. Remarkably, highest proliferative activity was observed within the neuronal nodules. Comparative genomic hybridization revealed a gain of chromosome 7q and a loss on chromosome 9p.

Adult↗

PubMed2001

Increased chromosomal imbalances in recurrent pituitary adenomas.

Eight pituitary adenomas (four gonadotroph cell adenomas, three prolactin cell adenomas, one null cell adenoma) and their respective recurrences in the same patients were studied by comparative genomic hybridization. Chromosomal imbalances were found in seven of eight patients affecting two of eight primary and seven of eight recurrent tumors. Overall, pituitary adenomas showed an average of 1.6 chromosomal imbalances per primary and 3.4 per recurrent tumor (P < 0.01). Prolactin cell adenomas showed an average of 4.3 chromosomal changes per primary and 6.3 per recurrent tumor, which were significantly more common than in gonadotroph cell adenomas (0 vs 1.7 changes; P < 0.05) and the null cell adenoma (0 vs 1.0 changes; P < 0.05). The most common changes were gains of 4q (in three of eight recurrences), 5q, and 13q (in two of eight recurrences each) as well as losses of chromosome 2 (in both primary and recurring tumors of two patients), 1p, 8q, 10, and 12q (in two of eight recurrences). Minimal common regions associated with recurrent adenomas were gains of 4q31.2-34 (three recurrences), 5q14-23 and 13q21-31 and losses of 12q24.3-qter (two recurrences each). The average MIB-1 proliferation indices were 1.2% for primary and 1.9% for recurrent adenomas (P < 0.005). Our findings suggest that acquisition of certain chromosomal imbalances is related to and may underlie adenoma recurrence.

Adult↗

PubMed2001

Chromosomal aberrations in pituitary carcinoma metastases.

Four pituitary carcinoma metastases [two adrenocorticotropic hormone (ACTH) and prolactin cell tumors each] were studied by comparative genomic hybridization. Chromosomal gains were found in all four carcinoma metastases, but losses only in the two prolactin cell carcinoma metastases. Overall, pituitary carcinoma metastases showed an average of 8.3 chromosomal imbalances per tumor (7 gains vs 1.3 losses), 10 in prolactin cell carcinoma metastases (7.5 gains vs 2.5 losses) and 6.5 in ACTH cell carcinoma metastases (6.5 gains vs 0 loss). The most common changes were gains of chromosome 5, 7p, and 14q (in three tumors each). High-level gains were found on 13q22-qter and 14q (two cases each) and on 1q, 3p, 7, 8, 9p, and 21q (one case each). To date, gains of chromosome 14q have not been reported among pituitary tumors. It remains to be shown whether gain of 14q is associated with malignant progression and metastatic dissemination of pituitary carcinomas.

ACTH Syndrome, Ectopic↗

PubMed2001

Sudden unexpected death in young adults with chronic hydrocephalus.

We present four cases of sudden unexpected death in young adults with chronic hydrocephalus. The patients were between 20 and 28 years of age and had suffered from aqueduct stenosis (two patients), spina bifida in combination with Arnold-Chiari malformation (type II) and fragile X-syndrome. The patients suddenly collapsed with cardiorespiratory failure and could not be resuscitated and none had a history of headache or seizures. The post-mortem examinations revealed no unusual findings and a definite cause of death could not be established. Neuropathological examination revealed chronically hydrocephalic brains without any signs of uncal or tonsillar herniation. We hypothesise that a sudden pressure-induced decompensation of cerebral neuronal pathways involving insular and limbic cortex, hypothalamus and brain stem nuclei, may have caused disturbances of the cardiopulmonary control centres in the reticular formation of the brain stem, which in turn may have led to instantaneous cardiorespiratory arrest resulting in sudden "neurogenic" cardiac death.

Adult↗

PubMed2001

Neglect-associated fatal Marchiafava-Bignami disease in a non-alcoholic woman.

We present the case of an 80-year-old malnourished and non-alcoholic woman who died from neglect-associated Marchiafava-Bignami disease, an illness usually almost exclusively occurring in male alcoholics. The patient had been bedridden for several months and had been looked after by her son. The patient was admitted to hospital in an extremely poor care condition suffering from severe exsiccosis, pressure sores and marasmus and died shortly afterwards. The initial post-mortem examination could not establish a definite cause of death, however, upon neuropathological examination a necrotising cystic lesion in the left cingulate gyrus as well as a central necrosis in the corpus callosum indicative of Marchiafava-Bignami disease were revealed. This is the first known case of Marchiafava-Bignami disease in a non-alcoholic woman and the first case in the forensic setting of neglect.

Aged↗

PubMed2001

Pediatric high-grade astrocytomas show chromosomal imbalances distinct from adult cases.

We studied 23 pediatric high-grade astrocytomas by comparative genomic hybridization. Chromosomal imbalances were found in 10 of 10 anaplastic astrocytomas and 11 of 13 glioblastomas and consisted of +1q (43%), +3q (26%), +1p, +2q, +5q (22%), -22q (34%), -6q, -10q (30%), -9q, -11q, -13q, -16q, and -17p (22%). Anaplastic astrocytomas frequently showed +5q (40%), +1q (30%), -22q (50%), -6q, -9q (40%), and -12q (30%); glioblastomas +1q (54%), +3q (38%), +2q, +17q (23%), -6q, -8q, -10q, -13q, and -17p (31%). Minimal common regions mapped to +1q21-41, +3q27-qter, +2q31-32, +5q14-22, -22q12-qter, -10q23-25, -6q25-qter, -9q34.2, -11q14-22, -16q22-qter, and -17p. High-level gains were located on 1q (7 cases), 2q, 7q (4 cases), 3q (3 cases), 9, 17q (2 cases), 4q, 8q, 18, and 20q (1 case). A significantly shorter survival was found for anaplastic astrocytomas showing +1q (P: < 0.05), MIB-1 proliferation index >25% (P: < 0.001) and glioblastomas (P: < 0.05). Compared with adult cases, +1p, +2q, and +21q as well as -6q, -11q, and -16q were more frequent in pediatric malignant astrocytomas. Among the latter +5q, -6q, -9q, -12q, and -22q were characteristic for pediatric anaplastic astrocytomas and +1q, +3q, +16p, -8q, and -17p for pediatric glioblastomas. Our results show that chromosomal aberrations differ between pediatric anaplastic astrocytomas and glioblastomas as well as between pediatric and adult high-grade astrocytomas, supporting the notion of a different genetic pathway. Furthermore, gains of chromosomal material on 1q might be correlated with a worse prognosis in pediatric anaplastic astrocytomas.

Adolescent↗

PubMed2000

[Progressive multifocal leukoencephalopathy in AIDS. Overview and retrospective analysis of 17 patients].

We describe retrospectively the course of 17 AIDS patients with progressive multifocal leukoencephalopathy (PML) and give a review of their clinical symptoms and survival times. The relative frequency of PML in our cohort of AIDS patients was 2.6%. The mean of CD4-positive cells was 80.5 +/- 82.5/microliter. CD4-positive cells were > 200/microliter only in one patient and increased significantly under a combination of three antiretroviral drugs whereas, with the other patients, CD4-positive cells did not increase with a maximum of two antiretroviral drugs. The mean survival time was 6.6 (1.5-20) months and correlated positively with the number of CD4-positive cells. The diagnosis of PML can be regarded as confirmed when JC-virus DNA is detectable in cerebrospinal fluid, typical changes can be seen in MRI and typical clinical symptoms occur. No effective therapy is known to date. Single case reports on therapy with cidofovir, as in one of the cases described here, showed positive results.

AIDS-Related Opportunistic Infections↗

PubMed2000

Cerebral malakoplakia associated with Escherichia coli infection.

Malakoplakia is an unusual chronic inflammatory disease occurring predominantly in the bladder and only rarely affecting other organs. For the urinary tract, its aetiology has been ascribed to the presence of Escherichia coli, while the very few cases of cerebral malakoplakia which have been reported so far, have mostly occurred in infants in the clinical setting of neonatal herpes virus infection or otherwise in adults in areas of cerebral infarction. We here report a case of E. coli-associated malakoplakia of the brain. It occurred in a 53-year-old man who had undergone long-term corticosteroid therapy and had previously been operated on a cerebral E. coli-associated abscess. This case indicates that malakoplakia of the brain might also be a histiocytic reaction against bacterial antigens of the E. coli family.

Abscess↗

PubMed2000

Comparative genomic hybridization in pineal germ cell tumors.

Fifteen primary pineal germ cell tumors (8 germinomas, 4 mixed teratomas-germinomas, 2 immature teratomas, and 1 yolk sac tumor) and 2 recurrences of the yolk sac tumor were studied by comparative genomic hybridization (CGH). An average of 1.8 chromosomal changes per germinoma (0.5 gains vs 1.3 losses), 5.5 per mixed teratoma-germinoma (3.0 gains vs 2.5 losses), 3.5 per immature teratoma (2.0 gains vs 1.5 losses), and 2.0 in the yolk sac tumor (2 gains vs 0 losses) were found; the first recurrence showed 7 (4 gains vs 3 losses), the second 13 imbalances (8 gains vs 5 losses). The most frequent imbalances were gains on 12p (40%), 8q (27%), and 1q (20%) as well as losses on 13q (47%), 18q (33%), 9q and 11q (20% each). Among germinomas, the most common chromosomal changes were -13q and -18q (38% each), in mixed teratomas-germinomas +8q (100%), +12p (75%), -13q (75%) and -9q (50%). Seven high-level gains were identified: 5 in mixed teratomas-germinomas (+8q: 3 cases, + 12p: 2 cases), 1 each in a germinoma (+2p) and an immature teratoma (+12p). Minimal common regions of over- and underrepresentation were found on +8q11.22-21.1, +12p11.1-12.1, -9q32-qter, -11q23.2-qter, -13q32-qter and -18q22-qter. Our findings suggest, that imbalances in cerebral germ cell tumors affect the same chromosomes as among their extracerebral counterparts, albeit in a considerably lower frequency among cerebral germinomas where +12p does not seem to play a major role.

Adolescent↗

PubMed1999

[Cidofovir (vistide) in therapy of progressive multifocal leukoencephalopathy in AIDS. Review of the literature and report of 2 cases].

The progressive multifocal leukoencephalopathy (PML), a complication of the acquired immunodeficiency syndrome (AIDS) in 4%-5% of all cases, is an encephalitis caused by the JC papovavirus. The prognosis is very poor with a mean survival time after diagnosis of 3 to 6 months. No effective therapy is known to date. Therapeutic trials in small groups of patients with alpha-interferon, didanosine, and arabinoside were of minor success. A controlled study with cytarabine did not show any efficacy. Single case reports on a therapy with cidofovir (Vistide), an approved nucleotide-analogone in the therapy of cytomegalovirus-retinitis in AIDS-patients without renal dysfunction, showed positive results. We describe 2 more cases of a therapy of cidofovir in AIDS-associated PML. Out of 22 cases described in the literature, including these 2 cases, with a therapy of cidofovir in AIDS-associated PML, 16 patients improved under therapy, 2 remained stable, and only 4 patients still worsened fulminantly. These results indicate an additive antiviral effect of cidofovir against JC-virus. This may be used in the therapy of PML in AIDS-patients because no alternative antiviral therapy of PML is available at present. The efficacy of cidofovir for the therapy of PML is suggested by case reports. The exact mechanisms leading to an improvement under a therapy with cidofovir in the 16 cases described so far should be evaluated in a randomised, controlled study with an adequate size of cohorts.

AIDS-Related Opportunistic Infections↗

PubMed1999

Neuropathology and prognosis of foetal brain tumours.

A survey of brain tumours that had been diagnosed prenatally by foetal sonography yielded 89 cases. The most commonly found tumour entities were teratomas (53.9%), glioblastomas (14.6%), lipomas (9. 0%), plexus papillomas (7.9%) and craniopharyngiomas (5.6%). The mean gestational age at ultrasound diagnosis was 30.0 weeks, ranging between 25.4 weeks in craniopharyngiomas and 35.3 weeks in lipomas. Girls were more frequently affected (57.4%; P < 0.05). The average maximum tumour size at diagnosis was 6.5 cm, ranging between 1.6 cm in lipomas and 8.2 cm in teratomas. Tumours diagnosed between 1979- 1988 accounted for 29.2% of all cases and were larger when identified than the ones reported between 1989- 1998 (5.9 vs 8.4 cm; P = 0.08). Of all patients, only 18.8% were alive after the first week and 10.5% after the 1st year of life. Prognosis was particularly poor among foetuses with brain tumours detected before 30 weeks' gestation of which 96.9% died. Significantly longer survival was found for lipomas (12.0 vs 3.8 months), tumour detection after gestational age of 30 weeks (6.3 vs 1.2 months) and in cases reported after 1988 (5.3 vs 2.9 months, all P < 0.05). Cytogenetic data was given for eight teratomas of which three showed a pathological and five cases a normal karyotype for both foetus and tumour. In conclusion, foetal brain tumours are rare neoplasms of whose cytogenetics little is known. They are mainly detected at the beginning of the third trimester of pregnancy with teratomas being the most common entity. Foetal brain tumours have a mainly unfavourable clinical outcome. However, their prognosis has improved in the last decade.

Brain↗

PubMed1999

Ependymoma of the cauda equina.

Myxopapillary ependymomas are benign tumours which occasionally metastasize along cerebrospinal fluid pathways. Extraneural metastases of spinal ependymomas, however, are very rare, even more so when situated in the pleura. We report the case of a 67 year old woman presenting with shortness of breath after recurrent myxopapillary ependymomas of the cauda equina. Chest X-ray showed multiple pleural lesions diagnosed as metastases of a myxopapillary ependymoma. The MIB-1 proliferation index was 3.1% for the initial spinal tumour, 14.2% for the first and 11.2% for the second recurrence while 12.0% for the pleural metastasis.

Aged↗

PubMed1999

Chromosomal imbalances in primary lymphomas of the central nervous system.

Twenty-two primary central nervous system lymphomas of immunocompetent adults were studied by comparative genomic hybridization. All were high-grade diffuse large B cell lymphomas. Comparative genomic hybridization revealed an average of 5.5 chromosomal changes per tumor, with gains being more common than losses (3.5 vs. 2.0). The most frequent DNA copy number changes were gains on chromosomes 1, 12, 18 (41% each), 7 (23%), and 11 (18%) and losses involving chromosomes 6 (59%), 18, and 20 (18% each). Commonly involved regions were +12q (41%), +18q (36%), +1q (32%), and +7q (23%), as well as -6q (50%), -6p (18%), -17p, and -18p (14% each). High-level gains were found on 7 chromosomes, mainly involving chromosomes 18q (23%), 12q (18%), and 1q (14%). Minimal common regions of over- and underrepresentation were found on +1q25-31, -6q16-21, +7q11.2, +12p11.2-13, +12q12-14, +12q22-24.1, and +18q12.2-21.3. A significant correlation between loss of DNA copy numbers on chromosome 6q and shorter survival could be established (10.2 vs. 22.3 months; P < 0.05). Our findings suggest that chromosomal imbalances of primary central nervous system lymphomas are similar to those of diffuse large B cell lymphomas at other locations and are probably not related to cerebral presentation; however, they may be prognostically relevant.

Adult↗

PubMed1998

Melanotic progonoma of the brain: a case report and review.

So far, only 25 melanotic progonomas have been found in the central nervous system (male/female ratio 3.5), mostly located in the cerebellum. The average age is 8 years (range 3.5 months to 69 years) with 85% becoming clinically apparent in the first decade of life; 73.7% of the patients reported succumbed to their disease at a mean age of 2.8 years, with a postoperative survival time of just 9 months. Systemic metastases were reported in 9 cases and had mostly spread via cerebrospinal fluid. In contrast to peripheral melanotic progonomas usually found in the maxilla, cerebral progonomas have a much worse outcome and have to be regarded as malignant. We present the case of a 1-year-old boy suffering from a melanotic progonoma of the pineal gland, who died at the age of 22 months with extensive spinal and abdominal metastases 10 months after partial removal of the tumor.

Abdominal Neoplasms↗

PubMed1998

Epidemiological features of brain tumors in the first 3 years of life.

We investigated the age-related location, gender distribution, and histology of 75 brain tumors in children under 3 years of age seen in our department between 1984 and 1997. These were characterized by a higher overall incidence in boys (42/33 cases; ratio 1.3) and a prevalence for a supratentorial location (48/27 cases; ratio 1.7); the most common histological entities were astrocytoma (25.3%) and ependymoma (17.3%), followed by medulloblastoma (13.3%) and PNET (10.8%); 44% were high-grade tumors corresponding to WHO grades III and IV. In the 1st (22 cases), 2nd (25 cases) and 3rd (28 cases) years of life, the boy-girl ratios were 1.0, 1.5 and 1.3, respectively, while there was a decrease with age in the frequency of supratentorial (ratios 3.4, 1.1, and 1.2) and high-grade tumors (77.3%, 36.0%, and 32.1%). In the 1st year of life the most common neoplasms were PNETs (22.7%) and in the 2nd year both astrocytomas and ependymomas (24.0 % each); astrocytomas (35.7%) prevailed in the 3rd year of life.

Age Distribution↗

PubMed1998

A unique case of cerebral spleen.

We present the first case of cerebral splenosis, occurring in a 20-year-old man 15 years after posttraumatic splenectomy. He became symptomatic through seizures and was operated on for suspected meningioma of the right occipital pole. Histologic evaluation of the lesion revealed splenic tissue with matching immunohistochemical results. Because no penetrating head injuries were reported at the time of trauma, a hematogenous spread of splenic tissue has to be assumed.

Adult↗