Magnetic resonance imaging detected radiation-induced changes in patients with proton radiation-treated arteriovenous malformations.

BACKGROUND: Treatment of intracranial arteriovenous malformations (AVMs) includes surgery, radiation therapy, endovascular occlusion, or a combination. Proton radiation therapy enables very focused radiation, minimizing dose to the surrounding brain. PURPOSE: To evaluate the presence of radiation-induced changes on post-treatment MRI in patients with AVMs treated with proton radiation and to compare these with development of symptoms and nidus obliteration. MATERIAL AND METHODS: Retrospective review of pre- and post-treatment digital subtraction angiography and MRI and medical records in 30 patients with AVMs treated with proton radiation. Patients were treated with two or five fractions; total radiation dose was 20-35 physical Gy. Vasogenic edema (minimal, perinidal, or severe), contrast enhancement (minimal or annular), cavitation and nidus obliteration (total, partial, or none) were assessed. RESULTS: 26 of 30 patients (87%) developed MRI changes. Vasogenic edema was seen in 25 of 30 (83%), abnormal contrast enhancement in 18 of 26 (69%) and cavitation in 5 of 30 (17%). Time from treatment to appearance of MRI changes varied between 5 and 25 months (median 7, mean 10). Seven patients developed new or deteriorating symptoms that required treatment with corticosteroids; all these patients had extensive MRI changes (severe vasogenic edema and annular contrast enhancement). Not all patients with extensive MRI changes developed symptoms. We found no relation between MRI changes and nidus obliteration. CONCLUSION: Radiation-induced MRI changes are seen in a majority of patients after proton radiation treatment of AVMs. Extensive MRI changes are associated with new or deteriorating symptoms.

Dynamic contrast-enhanced magnetic resonance imaging may act as a biomarker for vascular damage in normal appearing brain tissue after radiotherapy in patients with glioblastoma.

BACKGROUND: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a promising perfusion method and may be useful in evaluating radiation-induced changes in normal-appearing brain tissue. PURPOSE: To assess whether radiotherapy induces changes in vascular permeability (Ktrans) and the fractional volume of the extravascular extracellular space (Ve) derived from DCE-MRI in normal-appearing brain tissue and possible relationships to radiation dose given. MATERIAL AND METHODS: Seventeen patients with glioblastoma treated with radiotherapy and chemotherapy were included; five were excluded because of inconsistencies in the radiotherapy protocol or early drop-out. DCE-MRI, contrast-enhanced three-dimensional (3D) T1-weighted (T1W) images and T2-weighted fluid attenuated inversion recovery (T2-FLAIR) images were acquired before and on average 3.3, 30.6, 101.6, and 185.7 days after radiotherapy. Pre-radiotherapy CE T1W and T2-FLAIR images were segmented into white and gray matter, excluding all non-healthy tissue. Ktrans and Ve were calculated using the extended Kety model with the Parker population-based arterial input function. Six radiation dose regions were created for each tissue type, based on each patient's computed tomography-based dose plan. Mean Ktrans and Ve were calculated over each dose region and tissue type. RESULTS: Global Ktrans and Ve demonstrated mostly non-significant changes with mean values higher for post-radiotherapy examinations in both gray and white matter compared to pre-radiotherapy. No relationship to radiation dose was found. CONCLUSION: Additional studies are needed to validate if Ktrans and Ve derived from DCE-MRI may act as potential biomarkers for acute and early-delayed radiation-induced vascular damages. No dose-response relationship was found.

Perfusion Magnetic Resonance Imaging Changes in Normal Appearing Brain Tissue after Radiotherapy in Glioblastoma Patients may Confound Longitudinal Evaluation of Treatment Response.

BACKGROUND: The aim of this study was assess acute and early delayed radiation-induced changes in normal-appearing brain tissue perfusion as measured with perfusion magnetic resonance imaging (MRI) and the dependence of these changes on the fractionated radiotherapy (FRT) dose level. PATIENTS AND METHODS: Seventeen patients with glioma WHO grade III-IV treated with FRT were included in this prospective study, seven were excluded because of inconsistent FRT protocol or missing examinations. Dynamic susceptibility contrast MRI and contrast-enhanced 3D-T1-weighted (3D-T1w) images were acquired prior to and in average (standard deviation): 3.1 (3.3), 34.4 (9.5) and 103.3 (12.9) days after FRT. Pre-FRT 3D-T1w images were segmented into white- and grey matter. Cerebral blood volume (CBV) and cerebral blood flow (CBF) maps were calculated and co-registered patient-wise to pre-FRT 3D-T1w images. Seven radiation dose regions were created for each tissue type: 0-5 Gy, 5-10 Gy, 10-20 Gy, 20-30 Gy, 30-40 Gy, 40-50 Gy and 50-60 Gy. Mean CBV and CBF were calculated in each dose region and normalised (nCBV and nCBF) to the mean CBV and CBF in 0-5 Gy white- and grey matter reference regions, respectively. RESULTS: Regional and global nCBV and nCBF in white- and grey matter decreased after FRT, followed by a tendency to recover. The response of nCBV and nCBF was dose-dependent in white matter but not in grey matter. CONCLUSIONS: Our data suggest that radiation-induced perfusion changes occur in normal-appearing brain tissue after FRT. This can cause an overestimation of relative tumour perfusion using dynamic susceptibility contrast MRI, and can thus confound tumour treatment evaluation.

Hypofractionated high-energy proton-beam irradiation is an alternative treatment for WHO grade I meningiomas.

BACKGROUND: Radiation treatment is commonly employed in the treatment of meningiomas. The aim of this study was to evaluate the effectiveness and safety of hypofractionated high-energy proton therapy as adjuvant or primary treatment for WHO grade I meningiomas. METHOD: A total of 170 patients who received irradiation with protons for grade I meningiomas between 1994 and 2007 were included in the study. The majority of the tumours were located at the skull base (n = 155). Eighty-four patients were treated post subtotal resection, 42 at tumour relapse and 44 with upfront radiotherapy after diagnosis based on the typical radiological image. Irradiation was given in a hypofractionated fashion (3-8 fractions, usually 5 or 6 Gy) with a mean dose of 21.9 Gy (range, 14-46 Gy). All patients were planned for follow-up with clinical controls and magnetic resonance imaging scans at 6 months and 1, 2, 3, 5, 7 and 10 years after treatment. The median follow-up time was 84 months. Age, gender, tumour location, Simpson resection grade and target volume were assessed as possible prognostic factors for post-irradiation tumour progression and radiation related complications. RESULTS: The actuarial 5- and 10-year progression-free survival rates were 93% and 85% respectively. Overall mortality rate was 13.5%, while disease-specific mortality was 1.7% (3/170 patients). Older patients and patients with tumours located in the middle cranial fossa had a lower risk for tumour progression. Radiation-related complications were seen in 16 patients (9.4%), with pituitary insufficiency being the most common. Tumour location in the anterior cranial fossa was the only factor that significantly increased the risk of complications. CONCLUSIONS: Hypofractionated proton-beam radiation therapy may be used particularly in the treatment of larger World Health Organisation grade I meningiomas not amenable to total surgical resection. Treatment is associated with high rates of long-term tumour growth control and acceptable risk for complications.

Long-term evaluation of the effect of hypofractionated high-energy proton treatment of benign meningiomas by means of (11)C-L-methionine positron emission tomography.

PURPOSE: To determine if (11)C-L-methionine PET is a useful tool in the evaluation of the long-term effect of proton beam treatment in patients with meningioma remnant. METHODS: Included in the study were 19 patients (4 men, 15 women) with intracranial meningioma remnants who received hypofractionated high-energy proton beam treatment. Patients were examined with (11)C-L-methionine PET and MRI prior to treatment and after 6 months, and 1, 2, 3, 5, 7 and 10 years. Temporal changes in methionine uptake ratio, meningioma volume, meningioma regrowth and clinical symptoms throughout the follow-up period were evaluated. RESULTS: In 17 patients the tumour volume was unchanged throughout the follow-up. The methionine uptake ratio on PET decreased over the years in most patients. In two patients the tumour remnant showed progression on MRI. In these patients, prior to the volume increase on MRI, the methionine uptake ratio increased. One patient experienced transient clinical symptoms and showed radiological evidence of a radiation-induced reaction close to the irradiated field. CONCLUSION: Proton beam treatment is a safe and effective treatment for achieving long-term growth arrest in meningioma remnants. Follow-up with (11)C-L-methionine PET may be a valuable adjunct to, but not a replacement for, standard radiological follow-up.

Positive correlation between occlusion rate and nidus size of proton beam treated brain arteriovenous malformations (AVMs).

BACKGROUND: Proton beam radiotherapy of arteriovenous malformations (AVM) in the brain has been performed in Uppsala since 1991. An earlier study based on the first 26 patients concluded that proton beam can be used for treating large and medium sized AVMs that were considered difficult to treat with photons due to the risk of side effects. In the present study we analyzed the result from treating the subsequent 65 patients. MATERIAL AND METHODS: A retrospective review of the patients' medical records, treatment protocols and radiological results was done. Information about gender, age, presenting symptoms, clinical course, the size of AVM nidus and rate of occlusion was collected. Outcome parameters were the occlusion of the AVM, clinical outcome and side effects. RESULTS: The rate of total occlusion was overall 68%. For target volume 0-2 cm(3) it was 77%, for 3-10 cm(3) 80%, for 11-15 cm(3) 50% and for 16-51 cm(3) 20%. Those with total regress of the AVM had significantly smaller target volumes (p < 0.009) higher fraction dose (p < 0.001) as well as total dose (p < 0.004) compared to the rest. The target volume was an independent predictor of total occlusion (p = 0.03). There was no difference between those with and without total occlusion regarding mean age, gender distribution or symptoms at diagnosis. Forty-one patients developed a mild radiation-induced brain edema and this was more common in those that had total occlusion of the AVM. Two patients had brain hemorrhages after treatment. One of these had no effect and the other only partial occlusion from proton beams. Two thirds of those presenting with seizures reported an improved seizure situation after treatment. CONCLUSION: Our observations agree with earlier results and show that proton beam irradiation is a treatment alternative for brain AVMs since it has a high occlusion rate even in larger AVMs.

PTPN6 expression is epigenetically regulated and influences survival and response to chemotherapy in high-grade gliomas.

The prognosis of high-grade glioma patients is poor, and the tumors are characterized by resistance to therapy. The aims of this study were to analyze the prognostic value of the expression of the protein tyrosine phosphatase non-receptor type 6 (PTPN6, also referred to as SHP1) in high-grade glioma patients, the epigenetic regulation of the expression of PTPN6, and the role of its expression in chemotherapy resistance in glioma-derived cells. PTPN6 expression was analyzed with immunohistochemistry in 89 high-grade glioma patients. Correlation between PTPN6 expression and overall survival was analyzed with Kaplan-Meier univariate analysis and Cox regression multivariate analysis. Differences in drug sensitivity to a panel of 16 chemotherapeutic drugs between PTPN6-overexpressing clones and control clones were analyzed in vitro with the fluorometric microculture cytotoxicity assay. Cell cycle analysis was done with Krishan staining and flow cytometry. Apoptosis was analyzed with a cell death detection ELISA kit as well as cleaved caspase-3 and caspase-9 Western blotting. Autophagy was analyzed with LC3B Western blotting. Methylation of the PTPN6 promoter was analyzed with bisulfite pyrosequencing, and demethylation of PTPN6 was done with decitabine treatment. The PTPN6 expression correlated in univariate analysis to poor survival for anaplastic glioma patients (p = 0.026). In glioma-derived cell lines, overexpression of PTPN6 caused increase resistance (p < 0.05) to the chemotherapeutic drugs bortezomib, cisplatin, and melphalan. PTPN6 expression did not affect bortezomib-induced cell cycle arrest, apoptosis, or autophagy. Low PTPN6 promoter methylation correlated to protein expression, and the protein expression was increased upon demethylation in glioma-derived cells. PTPN6 expression may be a factor contributing to poor survival for anaplastic glioma patients, and in glioma-derived cells, its expression is epigenetically regulated and influences the response to chemotherapy.

Time trends in T3 to T4 laryngeal cancer: a population-based long-term analysis.

BACKGROUND: A decline in laryngectomies and survival in laryngeal cancer has been reported, especially among patients with advanced tumors. METHODS: Of 1058 patients with laryngeal cancer diagnosed from 1978 to 2007 in the Uppsala-Örebro region in Sweden, 263 T3 to T4 tumors treated with curative intent were studied retrospectively. Two time periods were defined, 1978 to 1992 and 1993 to 2007. RESULTS: Glottic tumors decreased constituting 68.6% of cases in 1978 to 1992 and 47.9% in 1993 to 2007. Laryngectomies were performed in 38.8% and 34.5% in the corresponding time periods. The use of laryngectomy was not strongly prognostic. A decline in overall survival (OS) over time could only be identified for the first year of follow-up. Chemotherapy was only used in a minority of cases. CONCLUSION: The marked decrease of glottic site may mark a shift in etiology. Laryngectomy was not strongly associated with improved survival. The absence of improved survival calls for intensified research.

Vandetanib combined with a p38 MAPK inhibitor synergistically reduces glioblastoma cell survival.

The survival for patients with high-grade glioma is poor, and only a limited number of patients respond to the therapy. The aim of this study was to analyze the significance of using p38 MAPK phosphorylation as a prognostic marker in high-grade glioma patients and as a therapeutic target in combination chemotherapy with vandetanib. p38 MAPK phosphorylation was analyzed with immunohistochemistry in 90 high-grade glioma patients. Correlation between p38 MAPK phosphorylation and overall survival was analyzed with Mann-Whitney U test analysis. The effects on survival of glioblastoma cells of combining vandetanib with the p38 MAPK inhibitor SB 203580 were analyzed in vitro with the median-effect method with the fluorometric microculture cytotoxicity assay. Two patients had phosphorylated p38 MAPK in both the cytoplasm and nucleus, and these two presented with worse survival than patients with no detectable p38 MAPK phosphorylation or phosphorylated p38 MAPK only in the nucleus. This was true for both high-grade glioma patients (WHO grade III and IV, n = 90, difference in median survival: 6.1 months, 95 % CI [0.20, 23], p = 0.039) and for the subgroup with glioblastoma patients (WHO grade IV, n = 70, difference in median survival: 6.1 months, 95 % CI [0.066, 23], p = 0.043). The combination of vandetanib and the p38 MAPK inhibitor SB 203580 had synergistic effects on cell survival for glioblastoma-derived cells in vitro. In conclusion, p38 MAPK phosphorylation may be a prognostic marker for high-grade glioma patients, and vandetanib combined with a p38 MAPK inhibitor may be useful combination chemotherapy for glioma patients.

Synergistic interactions between camptothecin and EGFR or RAC1 inhibitors and between imatinib and Notch signaling or RAC1 inhibitors in glioblastoma cell lines.

PURPOSE: The current treatment strategies for glioblastoma have limited health and survival benefits for the patients. A common obstacle in the treatment is chemoresistance. A possible strategy to evade this problem may be to combine chemotherapeutic drugs with agents inhibiting resistance mechanisms. The aim with this study was to identify molecular pathways influencing drug resistance in glioblastoma-derived cells and to evaluate the potential of pharmacological interference with these pathways to identify synergistic drug combinations. METHODS: Global gene expressions and drug sensitivities to three chemotherapeutic drugs (imatinib, camptothecin and temozolomide) were measured in six human glioblastoma-derived cell lines. Gene expressions that correlated to drug sensitivity or resistance were identified and mapped to specific pathways. Selective inhibitors of these pathways were identified. The effects of six combinations of inhibitors and chemotherapeutic drugs were evaluated in glioblastoma-derived cell lines. Drug combinations with synergistic effects were also evaluated in non-cancerous epithelial cells. RESULTS: Four drug combinations had synergistic effects in at least one of the tested glioblastoma-derived cell lines; camptothecin combined with gefitinib (epidermal growth factor receptor inhibitor) or NSC 23766 (ras-related C3 botulinum toxin substrate 1 inhibitor) and imatinib combined with DAPT (Notch signaling inhibitor) or NSC 23766. Of these, imatinib combined with DAPT or NSC 23766 did not have synergistic effects in non-cancerous epithelial cells. Two drug combinations had at least additive effects in one of the tested glioblastoma-derived cell lines; temozolomide combined with gefitinib or PF-573228 (focal adhesion kinase inhibitor). CONCLUSION: Four synergistic and two at least additive drug combinations were identified in glioblastoma-derived cells. Pathways targeted by these drug combinations may serve as targets for future drug development with the potential to increase efficacy of currently used/evaluated chemotherapy.

Haemangiopericytoma presenting with acute intracerebral haemorrhage--a case report and literature review.

BACKGROUND: Intracranial haemangiopericytoma (HPC), a rare malignant tumour, should be distinguished from meningioma and solitary fibrous tumour, which have been considered as separate entities since 1993, according to histopathology and clinical characteristics. METHODS: A PUBMED search for "Intracranial Haemangiopericytoma" yielded 176 articles, where 26 were of particular interest for this review article. CASE REPORT: Our patient, a 27-year-old man with HPC of grade III according to WHO, presents with an acute intracerebral haematoma, which is extremely rare. RESULTS: Surgery (total resection) is the primary treatment. Long-term close clinical and radiological follow-up is crucial due to the high rate of recurrence and tendency for development of metastasis. DISCUSSION: The effects of postoperative radiotherapy need further investigation. Besides neurosurgery, radiotherapy should always be considered in both patients with these highly malignant tumours (WHO grade III) and in patients with partial resection or inoperable cases (WHO grade II).

A review of dose-dense temozolomide alone and in combination with bevacizumab in patients with first relapse of glioblastoma.

Treatment of patients with glioblastoma improved dramatically when concomitant and adjuvant temozolomide was added to external radiation therapy. The addition of this new treatment schedule as well as the improvements in individually-tailored radiation treatment, has resulted in a larger proportion of patients being fit for further treatment after first relapse. One of the most interesting combinations that have started to become part of the therapeutic arsenal in the daily clinic is dose-dense temozolomide in combination with bevacizumab. We reviewed and compiled the literature concerning the present topic based on a search of the PubMed database (http://www.ncbi.nlm.nih.gov/pubmed/) for the years between 1995 and 2011. The clinical studies that have been performed are small and divergent, making it difficult to grade the scientific evidence for the combinatorial treatment of dose-dense temozolomide and bevacizumab. However, the available studies and the experience we have at our departments suggest that this combination is of interest for glioblastoma patients experiencing first relapse. More randomized clinical trials are needed in order to establish the standard of treatment at first relapse in patients with glioblastoma.

Molecular profiling using tissue microarrays as a tool to identify predictive biomarkers in laryngeal cancer treated with radiotherapy.

AIM: To explore the usefulness of the expression of five potential cancer biomarkers in predicting outcome in patients with laryngeal cancer. MATERIALS AND METHODS: In the present study, the Swedish National Cancer Registry databases were used to identify patients with laryngeal cancer diagnosed during the years 1978-2004 in the Uppsala-Orebro region and treated with radiotherapy. The expression of Ki-67, MutS homolog 2, (MSH2), p53, B-cell CLL/lymphoma 2 (Bcl-2) and cyclin D1 in the cancer cells was assessed immunohistochemically using tissue microarrays (TMAs) and its predicitve value on survival and relapse was analyzed using Cox regression models. RESULTS: A total of 39 patients were included in the present study. Nuclear MSH2 staining was statistically significantly correlated to Ki-67 expression (p=0.022). However, univariate and multivariate Cox analyses showed no statistically significant association between the expression of the investigated biomarkers and overall survival or relapse. CONCLUSION: The present exploratory study does not show any significant predictive value of the biomarkers examined with respect to survival or relapse. However, with larger patient cohorts, we believe that protein profiling using TMAs and immunohistochemistry is a feasible strategy for prognostic and predictive biomarker screening in laryngeal cancer.

Impact of age at diagnosis on prognosis and treatment in laryngeal cancer.

BACKGROUND: The aims of this study were to analyze how age affects treatment and treatment outcome, and to determine whether tumor characteristics differ between different age groups with laryngeal cancer. METHODS: Patients with laryngeal cancer during 1978-2004 in the Uppsala-Orebro region in Sweden were retrospectively studied. RESULTS: There were no significant differences in the 945 cases between age groups concerning major patient and tumor characteristics, such as male/female ratio, distribution of glottic/supraglottic tumors, stage, or site of recurrence. Overall survival (OS) and disease-specific survival (DSS) were worse among the oldest, although a significant proportion was cured. Relapse risk was lower among the oldest (12%) compared with the youngest (23%). The risk of never becoming tumor-free was 25% among the oldest and 7% in the youngest. Among the most elderly, only 1 late recurrence occurred. CONCLUSION: Elderly patients with laryngeal carcinoma cope well with treatment. Undertreatment may determine outcome more than age. The oldest group should be followed for a minimum of 2 years.

Characterization of novel and complex genomic aberrations in glioblastoma using a 32K BAC array.

Glioblastomas (GBs) are malignant CNS tumors often associated with devastating symptoms. Patients with GB have a very poor prognosis, and despite treatment, most of them die within 12 months from diagnosis. Several pathways, such as the RAS, tumor protein 53 (TP53), and phosphoinositide kinase 3 (PIK3) pathways, as well as the cell cycle control pathway, have been identified to be disrupted in this tumor. However, emerging data suggest that these aberrations represent only a fraction of the genetic changes involved in gliomagenesis. In this study, we have applied a 32K clone-based genomic array, covering 99% of the current assembly of the human genome, to the detailed genetic profiling of a set of 78 GBs. Complex patterns of aberrations, including high and narrow copy number amplicons, as well as a number of homozygously deleted loci, were identified. Amplicons that varied both in number (three on average) and in size (1.4 Mb on average) were frequently detected (81% of the samples). The loci encompassed not only previously reported oncogenes (EGFR, PDGFRA, MDM2, and CDK4) but also numerous novel oncogenes as GRB10, MKLN1, PPARGC1A, HGF, NAV3, CNTN1, SYT1, and ADAMTSL3. BNC2, PTPLAD2, and PTPRE, on the other hand, represent novel candidate tumor suppressor genes encompassed within homozygously deleted loci. Many of these genes are already linked to several forms of cancer; others represent new candidate genes that may serve as prognostic markers or even as therapeutic targets in the future. The large individual variation observed between the samples demonstrates the underlying complexity of the disease and strengthens the demand for an individualized therapy based on the genetic profile of the patient.

Cancer of the parotid gland; long-term follow-up. A single centre experience on recurrence and survival.

BACKGROUND: The aim of the study was to investigate the results of treatment of malignant parotid gland tumours at a single centre during a 56 year period, focusing on tumour control and survival. PATIENTS AND METHODS: At Uppsala University Hospital, Sweden, 144 patients (73 male and 71 female) with parotid cancer were treated between 1948 and 2004. The mean and median ages were 62 and 65 years, respectively (range 16-89 years). Surgery was the primary treatment in 113 (78%) patients followed by radiotherapy in 81. Postoperative radiotherapy in doses of 64-66 Gy, where the intention was curative and delivered with either split course or not, was administered to a majority of patients after 1970. The split-course mode was practised between 1970 and 1989. The median follow-up time was 8.3 years for patients still alive. There were 57 (40%) relapses, of which 40 were local recurrences with 26 inside the treatment volume. RESULTS: The overall 5-year survival was 53%. The majority of tumour-related deaths appeared in the first 3-5 years after diagnosis. Age, co-morbidity, the presence of lymph node metastases, adenoid cystic carcinoma and extent of disease were important for outcome; gender, however, was not. We found no difference in the survival between patients following split course therapy versus continuous fractionation. No difference could be seen in the survival of patients treated in the 1970s versus the 1990s. CONCLUSIONS: Age, nodal engagement, a higher T-stage, adenoid cystic carcinoma histopathology, facial palsy and intercurrent disease worsen the outcome of patients, whereas gender does not. Treatment principles at our hospital have been surgery followed by radiotherapy since the early 1970s even though a split course technique was practised during a part of this period. Survival has not improved markedly. Thus, there is scope for improvement for this group of patients.

Boron neutron capture therapy (BNCT) for glioblastoma multiforme: a phase II study evaluating a prolonged high-dose of boronophenylalanine (BPA).

BACKGROUND AND PURPOSE: To evaluate the efficacy and safety of boron neutron capture therapy (BNCT) for glioblastoma multiforme (GBM) using a novel protocol for the boronophenylalanine-fructose (BPA-F) infusion. PATIENT AND METHODS: This phase II study included 30 patients, 26-69 years old, with a good performance status of which 27 have undergone debulking surgery. BPA-F (900 mg BPA/kg body weight) was given i.v. over 6h. Neutron irradiation started 2h after the completion of the infusion. Follow-up reports were monitored by an independent clinical research institute. RESULTS: The boron-blood concentration during irradiation was 15.2-33.7 microg/g. The average weighted absorbed dose to normal brain was 3.2-6.1 Gy (W). The minimum dose to the tumour volume ranged from 15.4 to 54.3 Gy (W). Seven patients suffered from seizures, 8 from skin/mucous problem, 5 patients were stricken by thromboembolism and 4 from abdominal disturbances in close relation to BNCT. Four patients displayed 9 episodes of grade 3-4 events (WHO). At the time for follow-up, minimum ten months, 23 out of the 29 evaluable patients were dead. The median time from BNCT treatment to tumour progression was 5.8 months and the median survival time after BNCT was 14.2 months. Following progression, 13 patients were given temozolomide, two patients were re-irradiated, and two were re-operated. Patients treated with temozolomide lived considerably longer (17.7 vs. 11.6 months). The quality of life analysis demonstrated a progressive deterioration after BNCT. CONCLUSION: Although, the efficacy of BNCT in the present protocol seems to be comparable with conventional radiotherapy and the treatment time is shorter, the observed side effects and the requirement of complex infrastructure and higher resources emphasize the need of further phase I and II studies, especially directed to improve the accumulation of (10)B in tumour cells.

Clinical impact of positron emission tomography (PET) with (18F)fluorodeoxyglucose (FDG) in head and neck tumours.

CONCLUSION: PET plays an important role in staging, on suspicion of recurrence and for detection of occult primary tumours in the head and neck. OBJECTIVE: Since 1998 we have used positron emission tomography (PET) with (18F)fluorodeoxyglucose (FDG) to assess selected patients. This procedure has often helped in making decisions on staging and treatment. PATIENTS AND METHODS: The case records of the first 80 patients (104 PET examinations) were studied retrospectively. RESULTS: A total of 39 examinations were performed for staging. PET detected all primary tumours except two (stage T1), and staging was adjusted after 13%. In all, 33 PET examinations were performed on suspicion of recurrent tumour. In 52% of these PET determined further treatments; in 21% PET had a direct impact on the surgical planning. In 18 patients with metastases from an occult primary tumour, PET detected 39% of those tumours; in 22% it was the sole modality to do so. No recurrences or second primary tumours were detected when PET was used for follow-up of clinically cured patients. Results were similar when squamous cell carcinomas (SCCs) were considered alone as compared to the complete material. The mean standardized uptake value (SUV) was higher for cases deemed tumour-positive than in negative cases.