Primer extension based quantitative polymerase chain reaction reveals consistent differences in the methylation status of the MGMT promoter in diffusely infiltrating gliomas (WHO grade II-IV) of adults

Diffusely infiltrating gliomas (WHO grade II-IV) are the most common primary brain tumours in adults. These tumours are not amenable to cure by surgery alone, so suitable biomarkers for adjuvant modalities are required to guide therapeutic decision-making. Epigenetic silencing of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene by promoter methylation has been associated with longer survival of patients with high-grade gliomas who receive alkylating chemotherapy; and molecular testing for the methylation status of the MGMT promoter sequence is regarded as among the most relevant of such markers. We have developed a primer extension-based assay adapted to formalin-fixed paraffin-embedded tissues that enables quantitative assessment of the methylation status of the MGMT promoter. The assay is very sensitive, highly reproducible, and provides valid test results in nearly 100% of cases. Our results indicate that oligodendrogliomas, empirically known to have a relatively favourable prognosis, are also the most homogeneous entities in terms of MGMT promoter methylation. Conversely, astrocytomas, which are more prone to spontaneous progression to higher grade malignancy, are significantly more heterogeneous. In addition, we show that the degree of promoter methylation correlates with the prevalence of loss of heterozygosity on chromosome arm 1p in the oligodendroglioma group, but not the astrocytoma group. Our results may have potentially important implications for clinical molecular diagnosis.

Targeted alpha-radionuclide therapy of functionally critically located gliomas with 213Bi-DOTA-[Thi8,Met(O2)11]-substance P: a pilot trial

Functionally critically located gliomas represent a challenging subgroup of intrinsic brain neoplasms. Standard therapeutic recommendations often cannot be applied, because radical treatment and preservation of neurological function are contrary goals. The successful targeting of gliomas with locally injected beta radiation-emitting (90)Y-DOTAGA-substance P has been shown previously. However, in critically located tumours, the mean tissue range of 5 mm of (90)Y may seriously damage adjacent brain areas. In contrast, the alpha radiation-emitting radionuclide (213)Bi with a mean tissue range of 81 microm may have a more favourable toxicity profile. Therefore, we evaluated locally injected (213)Bi-DOTA-substance P in patients with critically located gliomas as the primary therapeutic modality.

Quantitative analysis of O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation in patients with low-grade gliomas

Methylation of the MGMT promoter is supposed to be a predictive and prognostic factor in glioblastoma. Whether MGMT promoter methylation correlates with tumor response to temozolomide in low-grade gliomas is less clear. Therefore, we analyzed MGMT promoter methylation by a quantitative methylation-specific PCR in 22 patients with histologically verified low-grade gliomas (WHO grade II) who were treated with temozolomide (TMZ) for tumor progression. Objective tumor response, toxicity, and LOH of microsatellite markers on chromosomes 1p and 19q were analyzed. Histological classification revealed ten oligodendrogliomas, seven oligoastrocytomas, and five astrocytomas. All patients were treated with TMZ 200 mg/m2 on days 1-5 in a 4 week cycle. The median progression-free survival was 32 months. Combined LOH 1p and 19q was found in 14 patients; one patient had LOH 1p alone and one patient LOH 19q alone. The LOH status could not be determined in two patients and was normal in the remaining four. LOH 1p and/or 19q correlated with longer time to progression but not with radiological response to TMZ. MGMT promoter methylation was detectable in 20 patients by conventional PCR and quantitative analysis revealed the methylation status was between 12 and 100%. The volumetric response to chemotherapy analyzed by MRI and time to progression correlated with the level of MGMT promoter methylation. Therefore, our retrospective case series suggests that quantitative methylation-specific PCR of the MGMT promoter predicts radiological response to chemotherapy with TMZ in WHO grade II gliomas.

Correlation of 6-18F-fluoro-L-dopa PET uptake with proliferation and tumor grade in newly diagnosed and recurrent gliomas

6-(18)F-fluoro-l-dopa ((18)F-FDOPA) measured with PET as a biomarker of amino acid uptake has been investigated in brain tumor imaging. The aims of the current study were to determine whether the degree of (18)F-FDOPA uptake in brain tumors predicted tumor grade and was associated with tumor proliferative activity in newly diagnosed and recurrent gliomas.

Typical 3-D localization of tumor remnants of WHO grade II hemispheric gliomas--lessons learned from the use of intraoperative high-field MRI control

Complete resection of grade II gliomas might prolong survival but is not always possible. The goal of the study was to evaluate the location of unexpected grade II gliomas remnants after assumed complete removal with intraoperative (iop) MRI and to assess the reason for their non-detection.

Macrocephaly in neurofibromatosis type 1: a sign post for optic pathway gliomas?

Optic pathway gliomas, which occur in 15-20% of paediatric patients with neurofibromatosis type 1, are the most common central nervous system tumour associated with this neurocutaneous disorder. The detection of optic pathway gliomas is essential for further management but is often delayed in infancy due to oligosymptomatic progression and difficulties in clinical detection. Therefore, the aim of our study was to find a clinical indicator for the presence of optic pathway gliomas in children with neurofibromatosis type 1 in order to facilitate early diagnosis and initiate further ophthalmological and neuroimaging investigations.

Multiple small "imaging" branch-duct type intraductal papillary mucinous neoplasms (IPMNs) in familial pancreatic cancer: indicator for concomitant high grade pancreatic intraepithelial neoplasia?

Most screening programs for familial pancreatic cancer are currently based on endoscopic ultrasonography and/or magnetic resonance imaging (MRI). Cystic lesions, especially those suspicious for small intraductal pancreatic mucinous neoplasms (IPMNs) of the branch ducts, can be visualized in up to 40 % of individuals at risk, but their pathological importance in the setting of FPC is yet not well established. Individuals at risk from a prospective screening program for familial pancreatic cancer with small "imaging" IPMNs of the branch-duct type (BD-IPMN) who underwent pancreatic resection were analysed regarding clinico-pathological data and the locations of pancreatic lesions. Five of 125 individuals at risk who underwent screening had multiple small (size 2-10 mm) unicystic lesions and/or multicystic single lesions in the pancreatic body and tail suspicious for BD-IPMNs upon MRI imaging and decided to undergo surgical resection after interdisciplinary counselling, although none fulfilled the consensus criteria for IPMN resection. Histological examination revealed BD-IPMNs with low or moderate dysplasia of the gastric type in combination with multifocal PanIN2 and PanIN3 lesions in 4 individuals. The remaining patient had only tiny ductectasias in the pancreatic tail with multifocal PanIN 2 lesions in the entire gland and one PanIN3 lesion in the pancreatic head. Intriguingly, the location of the most dysplastic histological lesions (PanIN3) did not correspond to the preoperatively detected lesions and were not visible in preoperative imaging. In the setting of FPC, the presence of multiple small "imaging" BD-IPMNs may indicate the presence of high-grade PanIN lesions elsewhere in the pancreas.

Fatal myocardial infarction at 4.5 years in a case of homozygous familial hypercholesterolaemia

Management of homozygous familial hypercholesterolaemia is notoriously difficult. For these patients, LDL apheresis is considered the treatment of choice. Treatment initiation is advocated generally from the age of seven years onwards (Thompson et al., Atherosclerosis 198:247-255, 2008). Here, we present the case of a young girl from a large inbred family of Turkish descent with homozygous familial hypercholesterolaemia and fatal outcome at the early age of 4(1/2) years.In conclusion, this case suggests that management of homozygous familial hypercholesterolaemia may require earlier and more aggressive treatment, including LDL apheresis before the age of seven years.

Loss of heterozygosity 1p36 and 19q13 is a prognostic factor for overall survival in patients with diffuse WHO grade 2 gliomas treated without chemotherapy

PURPOSE: This study was conducted to elucidate the impact of loss of heterozygosity (LOH) for chromosomes 1p36 and 19q13 on the overall survival of patients with diffusely infiltrating WHO grade 2 gliomas treated without chemotherapy. PATIENTS AND METHODS: We assessed the LOH status of tumors from patients harboring WHO grade 2 gliomas diagnosed between 1991 and 2000. Patients were either followed after initial biopsy or treated by surgery and/or radiation therapy (RT). Overall survival, time to malignant transformation, and progression-free survival were last updated as of March 2005. RESULTS: Of a total of 79 patients, LOH 1p36 and LOH 19q13 could be assessed in 67 and 66 patients, respectively. The median follow-up after diagnosis was 6 years. Loss of either 1p or 19q, in particular codeletion(s) at both loci, was found to positively impact on both overall survival (log-rank P < .01), progression-free survival, and survival without malignant transformation (P < .05). Tumor volume (P < .0001), neurologic deficits at diagnosis (P < .01), involvement of more than one lobe (P < .01), and absence of an oligodendroglial component (P < .05) were also predictors of shorter overall survival. The extent of surgery was similar in patients with or without LOH 1p and/or 19q; RT was more frequently resorted to for patients without than for patients with LOH 1p/19q (30% v 60%). CONCLUSION: The presence of LOH on either 1p36 or 19q13, and in particular codeletion of both loci is a strong, nontreatment-related, prognostic factor for overall survival in patients with diffusely infiltrating WHO grade 2 gliomas.

Recurrent acute and chronic pancreatitis in two brothers with familial chylomicronemia syndrome

The chylomicronemia syndrome is well recognized as a rare etiologic factor of acute pancreatitis; however, whether hypertriglyceridemia can cause chronic pancreatitis (CP) remains unclear. We describe the long-time course of 2 brothers with the familial chylomicronemia syndrome caused by identical compound heterozygous mutations in the lipoprotein lipase (LPL) gene with markedly reduced LPL activity. Other etiologic factors were excluded, including mutations in the PRSS1, SPINK1, and CFTR gene. Although both brothers had recurrent acute pancreatitis and the same LPL genotype, CP became evident in only one patient. Progression to CP was associated with a more severe disease course. Thus, the chylomicronemia syndrome may cause CP in the absence of other known causative factors, and similar to alcoholic and hereditary CP, a more severe disease course is associated with disease progression.

Local targeting of malignant gliomas by the diffusible peptidic vector 1,4,7,10-tetraazacyclododecane-1-glutaric acid-4,7,10-triacetic acid-substance p

PURPOSE: Malignant glial brain tumors consistently overexpress neurokinin type 1 receptors. In classic seed-based brachytherapy, one to several rigid (125)I seeds are inserted, mainly for the treatment of small low-grade gliomas. The complex geometry of rapidly proliferating high-grade gliomas requires a diffusible system targeting tumor-associated surface structures to saturate the tumor, including its margins. EXPERIMENTAL DESIGN: We developed a new targeting vector by conjugating the chelator 1,4,7,10-tetraazacyclododecane-1-glutaric acid-4,7,10-triacetic acid to Arg(1) of substance P, generating a radiopharmaceutical with a molecular weight of 1,806 Da and an IC(50) of 0.88 +/- 0.34 nmol/L. Cell biological studies were done with glioblastoma cell lines. neurokinin type-1 receptor (NK1R) autoradiography was done with 58 tumor biopsies. For labeling, (90)Y was mostly used. To reduce the "cross-fire effect" in critically located tumors, (177)Lut and (213)Bi were used instead. In a pilot study, we assessed feasibility, biodistribution, and early and long-term toxicity following i.t. injection of radiolabeled 1,4,7,10-tetraazacyclododecane-1-glutaric acid-4,7,10-triacetic acid substance P in 14 glioblastoma and six glioma patients of WHO grades 2 to 3. RESULTS: Autoradiography disclosed overexpression of NK1R in 55 of 58 gliomas of WHO grades 2 to 4. Internalization of the peptidic vector was found to be specific. Clinically, the radiopharmeutical was distributed according to tumor geometry. Only transient toxicity was seen as symptomatic radiogenic edema in one patient (observation period, 7-66 months). Disease stabilization and/or improved neurologic status was observed in 13 of 20 patients. Secondary resection disclosed widespread radiation necrosis with improved demarcation. CONCLUSIONS: Targeted radiotherapy using diffusible peptidic vectors represents an innovative strategy for local control of malignant gliomas, which will be further assessed as a neoadjuvant approach.

Objective response to radiation therapy and long-term survival of patients with WHO grade II astrocytic gliomas with known LOH 1p/19q status

BACKGROUND: WHO grade II gliomas are often approached by radiation therapy (RT). However, little is known about tumor response and its potential impact on long-term survival. PATIENTS AND METHODS: Patients subjected to RT were selected from the own database of WHO grade II gliomas diagnosed between 1991 and 2000. The volumetric tumor response after RT was assessed based on magnetic resonance imaging and graded according to standard criteria as complete, partial (PR, >or= 50%), or minor (MR, 25% to <50%). RESULTS: There were 24 astrocytomas and three oligoastrocytomas. 21 patients (78%) were dead at follow-up (mean survival 74 months). None of the patients had chemotherapy. Objective response occurred in 14 patients (52%, five PR and nine MR) but was not associated with overall survival. The vast majority of the tumors had no loss of heterozygosity (LOH) 1p and/or 19q (86%). CONCLUSION: Approximately 50% of patients with astrocytic WHO grade II gliomas respond to RT despite the absence of LOH for 1p/19q. The potential predictive factors for response and the impact of response on overall survival remain unclear.