Patient Position Reproducibility in Fractionated Stereotactically Guided Conformal Radiotherapy Using the BrainLab? Mask System

Purpose: Dedicated mask systems nowadays allow the use of stereotactic radiotherapy in fractionated regimes, therefore combining the advantages of high precision radiotherapy with the biological benefit of fractionation. Therefore the knowledge of institution specific isocenter accuracy is essential for decision-making about margins to be allowed to form the planning target volume. Patients and Methods: Measurements of isocenter deviations during fractionated treatments were performed in 33 patients using the simulator Simulix-xy (Oldelft) in connection with the BrainLab^® angiographic localizer-box as well as port-films. In both cases repeated images were overlaid by use of anatomical landmarks with a methodical accuracy in the order of 0.5 mm. Results: Both methods yield random isocenter deviations of less then 2 mm (standard deviation) in all three directions and no significant systematic deviations. These values are in the order of the accuracy of the method, obtained by comparison of two independent investigators, as well as they are comparable with the literature. Conclusions: The accuracy of less than 2 mm indicates safety margins of 3-4 mm as sufficient for clinical routine to cover the target in 95.5% of all set-ups (2 SD). Ziel: Spezielle Maskensysteme erlauben heutzutage die Anwendung der stereotaktischen Strahlentherapie in fraktionierten Regimes und damit die Kombination der Vorteile der Hochpräzisionsbestrahlung mit dem biologischen Nutzen der Fraktionierung. Deshalb ist die Kenntnis der institutsspezifischen Genauigkeit der Isozentrumseinstellung eine notwendige Voraussetzung für die Entscheidung über die erforderlichen Sicherheitsabstände. Patienten und Methode: Die Messung der Isozentrumsgenauigkeit erfolgte bei 33 Patienten sowohl durch Simulatorkontrollen in Verbindung mit der BrainLab^®-Localizer-Box oder durch Verifikation mit Portfilmen. In beiden Fällen wurden die Filme anhand anatomischer Lankdmarken mit einer methodischen Sicherheit von unter 0,5 mm überlagert. Ergebnisse: Beide Methoden zeigten zufällige Isozentrumsabweichungen von weniger als 2 mm (Standardabweichung) in allen drei Raumebenen (Abbildung 1, Tabelle 2) und keine signifikanten systematischen Abweichungen. Damit liegen die Ergebnisse im Bereich der methodischen Genauigkeit, wie durch den Vergleich der Befunde zweier unabhängiger Untersucher gezeigt wird (Tabelle 1), und sind mit Literaturdaten gut vergleichbar. Schlussfolgerung: Die Genauigkeit von unter 2 mm zeigt, dass ein Sicherheitsabstand von 3-4 mm für die klinische Routine ausreichend ist, um bei 95,5% der Einstellung die sichere Erfassung des Targets zu garantieren.     

Patient Position Reproducibility in Fractionated Stereotactically Guided Conformal Radiotherapy Using the BrainLab® Mask System

PURPOSE: Dedicated mask systems nowadays allow the use of stereotactic radiotherapy in fractionated regimes, therefore combining the advantages of high precision radiotherapy with the biological benefit of fractionation. Therefore the knowledge of institution specific isocenter accuracy is essential for decision-making about margins to be allowed to form the planning target volume. PATIENTS AND METHOD: Measurements of isocenter deviations during fractionated treatments were performed in 33 patients using the simulator Simulix-xy (Oldelft) in connection with the BrainLab angiographic localizer-box as well as port-films. In both cases repeated images were overlaid by use of anatomical landmarks with a methodical accuracy in the order of 0.5 mm. RESULTS: Both methods yield random isocenter deviations of less then 2 mm (standard deviation) in all three directions and no significant systematic deviations. These values are in the order of the accuracy of the method, obtained by comparison of two independent investigators, as well as they are comparable with the literature. CONCLUSIONS: The accuracy of less than 2 mm indicates safety margins of 3-4 mm as sufficient for clinical routine to cover the target in 95.5% of all set-ups (2 SD).     

Genome-wide expression patterns of invasion front, inner tumor mass and surrounding normal epithelium of colorectal tumors

Background

The normal human prostate glandular epithelium has the unique function of accumulating high levels of zinc. In prostate cancer this capability is lost as an early event in the development of the malignant cells. The mechanism and factors responsible for the ability of the normal epithelial cells to accumulate zinc and the loss of this capability in the malignant cells need to be identified. We previously reported that Zip1 is an important zinc uptake transporter in prostate cells and is down regulated in the malignant cells in situ along with the depletion of zinc levels. In this report we investigated the expression of two other Zip family zinc transporters, Zip2 and Zip3 in malignant versus nonmalignant (normal and BPH) glands. Zip2 and Zip3 relative protein levels were determined by immunohistochemistry analysis of human prostate tissue sections.

Results

Normal and BPH glandular epithelium consistently exhibited the strong presence of both Zip 2 and Zip3; whereas both transporters consistently were essentially non-detectable in the malignant glands. This represents the first report of the expression of Zip3 in human prostate tissue; and more importantly, reveals that ZiP2 and Zip3 are down regulated in malignant cells in situ as we also had demonstrated for Zip1. Zip2 and Zip3 transporter proteins were localized predominantly at the apical cell membrane, which is in contrast to the Zip1 localization at the basolateral membrane. Zip2 and Zip3 seemingly are associated with the re-uptake of zinc from prostatic fluid.

Conclusion

These results coupled with previous reports implicate Zip2 and Zip3 along with Zip1 as important zinc uptake transporters involved in the unique ability of prostate cells to accumulate high cellular zinc levels. Zip1 is important for the extraction of zinc from circulation as the primary source of cellular zinc. Zip 2 and Zip3 appear to be important for retention of the zinc in the cellular compartment. The down regulation of all three transporters in the malignant cells is consistent with the loss of zinc accumulation in these cells. Since zinc imposes tumor suppressor effects, the silencing of the gene expression for these transporters is a required event for the manifestation of the malignant activities of the neoplastic cells. This now provides new insights into the genetic/molecular events associated with the development of prostate cancer; and supports our concept of Zip1, and now Zip2 and Zip3, as tumor suppressor genes and zinc as a tumor suppressor agent.     

Microflora changes with norfloxacin and pivmecillinam in women with recurrent urinary tract infection

Similar changes in the periurethral and vaginal microflora were observed in 19 women with recurrent urinary tract infection following treatment with norfloxacin (NOR) or pivmecillinam (PIV). Escherichia coli strains were suppressed by both treatments. Staphylococcus spp. and enterococci colony counts increased following PIV treatment in the periurethral flora but remained stable with NOR.     

Non-grafted sinus implants in periodontally compromised patients: a time-to-event analysis

This study reports the results of implant therapy involving a sinus membrane lift and of conventional implant therapy in 68 periodontally compromised patients treated between June 1990 and June 2002. Patients had at least two implants inserted, one of which was placed in the maxillary sinus region following fenestration of the lateral sinus wall and lifting of the sinus membrane. Two implant systems were used: a two-stage system (Astra) and a one-stage system (ITI). Annual follow-up visits included recording of plaque, probing pocket depth and measurement of the radiographic distance in millimeter from the implant shoulder to the alveolar crest. Survival analysis showed that the proportion of implants that had not been explanted after 5 years ranged between 88.7% for ITI sinus implants and 97% for ASTRA conventional implants. After 10 years, the proportion of implants remaining in situ ranged between 59% for ITI conventional implants and 97% for ASTRA conventional implants. Cox regression analyses showed that the factors influential for implant explantation were implant type (HR(ITI) = 2.8), implant length (HR(< or = 10 mm) = 3.1), patient being a smoker (HR(smoking) = 2.2) and patient having at least 20 natural teeth (HR(> or = 20 teeth) = 3.8). Our results demonstrate that sinus implants may be inserted with the same success as conventional implants in periodontally compromised patients.     

Coccidioidomycosis with cerebral and cerebellar granulomas

We discuss the diagnosis, treatment and prognosis of a Danish male with disseminated coccidioidomycosis. He presented with headaches and slight fever. Examination showed pulmonary, cutaneous and cerebral and cerebellar granulomas, a rare complication. He was treated with intravenously and subsequently orally administered fluconazole. Symptoms and clinical findings regressed during treatment.     

Cancer specific Mucin-1 glycoforms are expressed on multiple myeloma

Present therapies cannot cure the large majority of patients with multiple myeloma (MM) and therefore new treatment strategies are imperative. This study analysed the different glycosylation profiles of Mucin-1 (MUC1) on MM and acute myeloid leukaemia (AML) cells using a series of anti-MUC1 antibodies. Seventy-three per cent of the MM patients had plasma cells that expressed the fully glycosylated forms of MUC1. In contrast to controls, normal bone marrow cells and AML cells, the differentiation-dependent and cancer-associated glycoforms of MUC1 were present on 59% and 36% MM tumour cells respectively. This indicated that aberrantly glycosylated MUC1 is a potential immunotherapeutic target in MM patients.     

Randomized, double-blind comparison of acute beta1-blockade with 50 mg metoprolol tartrate vs 25 mg carvedilol in normal subjects

Differential efficacy of immediate-release metoprolol tartrate and carvedilol in the treatment of congestive heart failure remains a subject of ongoing debate. The degree of beta1-blockade can be assessed by percentage reduction of exercise heart rate. Twelve healthy subjects underwent symptom-limited cardiopulmonary exercise testing repeated weekly and 2 hours after randomized, double-blind administration of 50 mg metoprolol tartrate vs 25 mg carvedilol. Baseline heart rate, heart rate at 40% and 70% peak O2 consumption, and maximal exercise were significantly blunted more by metoprolol tartrate than by carvedilol (P<.05 for all). Peak O2 consumption was significantly reduced by metoprolol tartrate (P<.03) but not by carvedilol (P=.054). The change in O2 consumption was significantly correlated with the degree of beta1-blockade (r =0.45; P<.05). In healthy subjects, a higher degree of beta1-blockade is achieved with 50 mg metoprolol tartrate compared with 25 mg carvedilol.