Node-positive left-sided breast cancer: does VMAT improve treatment plan quality with respect to IMRT?

PURPOSE: The aim of the present work was to explore plan quality and dosimetric accuracy of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) for lymph node-positive left-sided breast cancer. METHODS: VMAT and IMRT plans were generated with the Pinnacle(3) V9.0 treatment planning system for 10 lymph node-positive left-sided breast cancer patients. VMAT plans were created using a single arc and IMRT was performed with 4 beams using 6, 10, and 15 MV photon energy, respectively. Plans were evaluated both manually and automatically using ArtiView™. Dosimetric plan verification was performed with a 2D ionization chamber array placed in a full scatter phantom. RESULTS: Photon energy had no significant influence on plan quality for both VMAT and IMRT. Large variability in low doses to the heart was found due to patient anatomy (range V(5 Gy) 26.5-95 %). Slightly more normal tissue dose was found for VMAT (e.g., V(Tissue30%) = 22 %) than in IMRT (V(Tissue30%) = 18 %). The manual and ArtiView™ plan evaluation coincided very accurately for most dose metrics (difference < 1 %). In VMAT, 96.7 % of detector points passed the 3 %/3 mm gamma criterion; marginally better accuracy was found in IMRT (98.3 %). CONCLUSION: VMAT for node-positive left-sided breast cancer retains target homogeneity and coverage when compared to IMRT and allows maximum doses to organs at risk to be reduced. ArtiView™ enables fast and accurate plan evaluation.

Low-grade gliomas -- current concepts.

Diffuse astrocytomas, oligodendrogliomas, and oligoastrocytomas (mixed gliomas) WHO grade II, pleomorphic xanthoastrocytomas (PXAs), pilocytic astrocytomas, and subependymal giant cell astrocytomas (SEGAs) are often referred to as low-grade gliomas. WHO grade II astrocytomas, oligodendrogliomas, and mixed gliomas are characterized by their infiltrative growth, frequent tumor recurrence and a more than 50 % risk for malignant progression. In contrast, pilocytic astrocytomas and SEGAs are circumscribed tumors amenable to a (radio)surgical cure. There are few universally accepted guidelines for the treatment of low-grade gliomas. In this review, three neurosurgeons, a neurologist, a neuropathologist, and a radiation oncologist discuss some of the difficult issues surrounding the diagnosis and treatment of low-grade gliomas from their individual points of view (i. e., classification and neuropathology, MR imaging, stereotactic biopsy, microsurgery, interstitial radiotherapy/brachytherapy, radiotherapy, wait and see strategy).

Influence of ionizing radiation on nucleus 24 cochlear implants.

HYPOTHESIS: To evaluate the influence of conventional or hyperfractionated radiotherapy on Nucleus CI24M or CI24R(CS) implant systems. BACKGROUND: As a consequence of more than 70,000 cochlear implant recipients worldwide, the potential need for radiotherapy is an issue requiring consideration by both implantees and implantation centers. Conditions requiring radiotherapy of the head may include head, neck, or brain tumors. METHODS: The study examines the effect of ionizing radiation on cochlear implant function. The implanted devices examined were the Nucleus CI24M and Nucleus CI24R(CS). In a modeled study, two implants of each type were treated with fraction schemes most frequently used in clinical routine (e.g., conventional fractionation [total dose, 120 Gy] and hyperfractionation [total dose, 116 Gy]). Parameters quantified were the implant output amplitude changes at high and low current level (current levels 255 and 100, respectively), the charge balance of the biphasic pulse, and the accuracy of the impedance telemetry function. RESULTS: Within the clinically relevant dose range (< 80 Gy), implant function in all four devices was normal. Failure occurred in one Nucleus CI24R(CS) device treated with hyperfractionation. A dramatic drop in the output amplitude at 106 Gy was observed, and the impedance measurement failed at a total dose of 111 Gy. CONCLUSION: The results suggest that conventional or hyperfractionated radiotherapy can be applied safely at Nucleus CI24M or CI24R(CS) implant systems in a patient-like setting. Therefore, the authors propose that the results of the study can be applicable in clinical practice.

[Brain metastases. Possibilities and limits of treatment]. / Hirnmetastasen. Möglichkeiten und Grenzen der Behandlung.

The objective of the treatment of brain metastases is not merely to control the disease, but also to preserve an acceptable quality of life by keeping neurological symptoms in abeyance for as long as possible. In most cases, symptoms may be due to considerable perifocal edema. This is responsive to treatment with steroids, and these are therefore given to all patients. Specific treatment regimens include microsurgical removal of metastatic lesions, radiosurgery, irradiation of the brain, and chemotherapy. The choice of the treatment modality is dictated by the general state of health of the patient, the location and size of the metastases, the number of such lesions, and systemic involvement.

Gliosarcoma: a clinical study.

BACKGROUND AND PURPOSE: Gliosarcomas are rare biphasic neoplasms of the central nervous system composed of a glioblastoma multiforme (GBM) admixed with a sarcomatous component. There are conflicting reports regarding their clinical aggressiveness. Four hundred and twenty-two consecutive patients with GBM were treated at our hospital between 1980 and 1999, among them 12 gliosarcomas. The goal of this study was to examine clinical features, treatment, survival and patterns of failure of gliosarcoma patients and to compare them with the entire group of GBM patients. This comparison was refined by a matched pair analysis with a group of 12 GBM patients selected for age, Karnofsky performance status, resection status, fractionation scheme and total dose (control GBM group). MATERIALS AND METHODS: Seven gliosarcoma patients were male, five female, with a median age of 56 years (range 37-76 years). The median tumor size was 4.5 cm (range 3-8 cm). The locations, all supratentorial, included temporal in six, parietal in five, frontal in four and occipital in one patient. All patients underwent tumor resection followed by postoperative radiation therapy. RESULTS: Median survival was 11.5 months for the gliosarcoma group, 8.1 months for the entire GBM group (log rank test, P=0.16) and 11.0 months for the control GBM group (log rank test, P=0.36). All gliosarcoma patients had local tumor recurrences and died due to neurologic causes within 19.3 months after radiation therapy. CONCLUSIONS: With regard to clinical features, survival and patterns of failure, gliosarcomas and GBM cannot be distinguished clinically. Therefore, the same principles should be applied for the treatment of these tumors.

Atypical teratoid/rhabdoid tumors in adult patients: case report and review of the literature.

Atypical teratoid/rhabdoid tumors (AT/RT) of the central nervous system are rare and extremely aggressive malignancies of early childhood. We report a case of AT/RT in an adult patient. A 30-year-old woman presented with headache, vomiting and ataxia during the second trimester of pregnancy. Magnetic resonance imaging revealed a posterior fossa mass. A gross total resection was performed. Pathological examination revealed an AT/RT. Despite the dismal prognosis the patient decided not to undergo an abortion. For this reason postoperative accelerated hyperfractionated radiotherapy was limited to the tumor region. Six months later the woman delivered a healthy baby. One week postpartum, a central nervous system recurrence localized apart from the primary lesion was treated with radiosurgery. Two months later a diffuse progression was noted. Despite a 6 week course of oral temozolomide, the tumor progressed and the patient died 11 months after diagnosis. Although survival was short, surgery and involved field radiotherapy yielded a progression-free interval of 9 months. This allowed the patient to carry pregnancy to term. Radiosurgery resulted in a complete remission of the first recurrence. Oral chemotherapy was not effective in controlling diffuse tumor spread.

Anemia is associated with decreased local control of surgically treated squamous cell carcinomas of the glottic larynx.

PURPOSE: A strong association between hemoglobin levels and tumor control exists in head and neck cancer treated with radiotherapy. This retrospective study has been performed to determine whether or not this association can also be found in the surgical setting. METHODS AND MATERIALS: Between January 1970 and December 1990, 258 patients with glottic SCC received conventional surgery only (T1/T2/T3/T4 n = 188/31/37/2, respectively). Locoregional control was calculated by the Kaplan-Meier method. The influence of hemoglobin, T stage, age, gender, performance/nutritional status, and grading was evaluated using a Cox model. RESULTS: Five-year locoregional control for T1a/T1b/T2/T3/T4 tumors was 91%/85%/76%/62%/0%, respectively (log-rank test, p < 0.0001). Anemia (male < 13, female < 12 g/dL hemoglobin) was present in 27 patients. It was associated with significantly worse 5-year locoregional control, i.e., 60% vs. 85% (log-rank test, p = 0.003). In multivariate analysis stratified for T stage, two variables were of influence: positive margins (relative risk [RR], 3.8; 95% confidence interval [CI], 1.7-8.4), anemia (RR, 3.0; 95% CI, 1.4-6.2). The largest subgroup consisted of 162 patients characterized by male gender, T1, and complete resection. In this subgroup, the significant variables were T stage (T1b vs. T1a; RR, 3.5; 95% CI, 0.96-12.4) and hemoglobin with a RR of 1.4 (95% CI, 1.0-2.1) per g/dL less analyzed as a continuous variable. CONCLUSION: Anemia is associated with a high risk of treatment failure in surgically treated glottic cancer. Hemoglobin levels might be predictive even within the normal range as indicated by subgroup analysis.

Is there any correlation between MDR1, GST-pi-expression and CEA?

BACKGROUND: The levels of mRNA-expression of multidrug resistance (MDR1) and glutathione-S-transferase pi (GST-pi) were measured and correlated with the immunohistochemical expressions of tumour markers. MATERIALS AND METHODS: Analysis of total mRNA was performed by Northern and slot blots. The expression of carcinoembryonic antigen (CEA) and other tumour markers was assessed by immunohistochemistry. The tumour panel comprised tumours of different histologies. RESULTS: CEA-positive tumours showed a significantly higher ex-pression of MDR1 and GST-pi than CEA-negative tumours. Wilcoxon-Test: mean rank of the MDR1 expression (14.3 vs. 7.8; p < 0.05) and GST-pi expression (15.3 vs. 5.9; p < 0.001). No other correlation could be found. CONCLUSIONS: The relationship of MDR1 and GST-pi with the tumour marker CEA implies that evaluation of CEA can help in discriminating between tumours with high or low expression of drug resistance. Furthermore, correlation between MDR1, GST-pi and CEA indicates that there might be a common mechanism, regulating drug resistance and expression of CEA.

Accelerated hyperfractionated radiotherapy in 149 patients with glioblastoma multiforme.

Between August 1986 and December 1997, 149 patients with glioblastoma were treated postoperatively with 1.5 Gy fractions three times daily to a total dose of 54 Gy with 4-h intervals. Median actuarial survival was 8.8 months. Survival was 31% at 12 months and 4% at 24 months. No severe acute toxicity occurred. Multivariate analysis revealed that only age < or = 60 years and lactate dehydrogenase levels < or = 240 U/l predicted significantly higher survival probabilities.