Possible Dose-Response Relationship in Palliative Radiotherapy for Non-bone Painful Lesions.

AIMS: Total radiation dose does not predict pain response in conventionally fractionated radiotherapy for bone metastases. By contrast, in radiotherapy for solid painful tumours other than bone metastases, it is unknown whether there is a dose-response relationship. We sought to determine whether a higher total radiation dose predicted a higher pain response rate in palliative radiotherapy for non-bone painful lesions. MATERIALS AND METHODS: We carried out a secondary analysis of a prospective observational study. For patients scheduled for radiotherapy for painful tumours, Brief Pain Inventory data were collected at baseline and at 1, 2 and 3 months after the start of radiotherapy. The predictive value of total radiation dose was evaluated using the Fine-Gray model, in which death without a pain response was treated as a competing risk. RESULTS: Of the 203 patients with solid painful tumours, 78 (38%) had non-bone painful lesions. There were no significant differences in pain response rate, the rate of the predominance of non-index pain or reductions in pain interference scores between the patients with non-bone lesions and those with bone metastases. Multivariable analysis showed that total radiation dose was an independent significant predictor of pain response in patients with non-bone painful lesions. This result was not robust to sensitivity analysis with Cox regression analysis. CONCLUSIONS: Higher total radiation dose seemed to be associated with a higher rate of pain response in patients with non-bone painful lesions. However, this finding was not robust to sensitivity analysis. Dose-response relationship should be investigated in clinical trials enrolling patients with these kinds of painful tumour.

Prognostic value of perfusion MR imaging of high-grade astrocytomas: long-term follow-up study.

BACKGROUND AND PURPOSE: Although the prognostic value of perfusion MR imaging in various gliomas has been investigated, that in high-grade astrocytomas alone has not been fully evaluated. The purpose of this study was to evaluate retrospectively whether the tumor maximum relative cerebral blood volume (rCBV) on pretreatment perfusion MR imaging is of prognostic value in patients with high-grade astrocytoma. MATERIALS AND METHODS: Between January 1999 and December 2002, 49 patients (30 men, 19 women; age range, 23-76 years) with supratentorial high-grade astrocytoma underwent MR imaging before the inception of treatment. The patient age, sex, symptom duration, neurologic function, mental status, Karnofsky Performance Scale, extent of surgery, histopathologic diagnosis, tumor component enhancement, and maximum rCBV were assessed to identify factors affecting survival. Kaplan-Meier survival curves, the logrank test, and the multivariate Cox proportional hazards model were used to evaluate prognostic factors. RESULTS: The maximum rCBV was significantly higher in the 31 patients with glioblastoma multiforme than in the 18 with anaplastic astrocytoma (P < .03). The 2-year overall survival rate was 67% for 27 patients with a low (< or =2.3) and 9% for 22 patients with a high (>2.3) maximum rCBV value (P < .001). Independent important prognostic factors were the histologic diagnosis (hazard ratio = 9.707; 95% confidence interval (CI), 3.163-29.788), maximum rCBV (4.739; 95% CI, 1.950-11.518), extent of surgery (2.692; 95% CI, 1.196-6.061), and sex (2.632; 95% CI, 1.153-6.010). CONCLUSION: The maximum rCBV at pretreatment perfusion MR imaging is a useful clinical prognostic biomarker for survival in patients with high-grade astrocytoma.

Impact of FDG-PET/CT fused imaging on tumor volume assessment of head-and-neck squamous cell carcinoma: intermethod and interobserver variations.

BACKGROUND: Although gross tumor volume (GTV) at the primary site can predict local control of head-and-neck squamous cell carcinoma (SCC) in patients who are treated with organ-preservation therapy, GTV assessment does not eliminate substantial interobserver variation. PURPOSE: To evaluate whether F-18-fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) fused imaging provides additional information for GTV assessment. MATERIAL AND METHODS: We obtained FDG-PET/CT fused images on 20 patients with head-and-neck SCC. All had undergone preoperative conventional workup, including contrast-enhanced CT and magnetic resonance imaging (MRI). The GTV of the primary tumors was designed by two independent observers who used routine clinical data. Observer A was a radiologist and observer B a radiation oncologist. GTV1 and GTV2 were designed without and with FDG-PET/CT, respectively. For geometric interobserver comparison, we calculated the concordance rate as the ratio of the intersection (AxB) of the GTVs to their union (AxB). Intermethod (GTV1 vs. GTV2) and interobserver (A vs. B) differences in the GTVs were assessed by Bland-Altman analysis and the Spearman rank-correlation test. The interobserver concordance rates for GTV1 and GTV2 were compared using a two-tailed paired-samples t test. RESULTS: On FDG-PET/CT, all primary tumors were visualized. There was no systemic trend for a volume difference between GTV1 and GTV2. Although the 95% limits of agreement were wider for interobserver than intermethod differences, the 95% limits of interobserver agreement were narrower for GTV2 than GTV1. The mean interobserver concordance rate for GTV2 was higher than for GTV1 (54.5% vs. 39.1%, P=0.0002). CONCLUSION: FDG-PET/CT is a useful modality for consistent GTV assessment, which should not be used as a single modality but rather to obtain supplemental information in patients with head-and-neck SCC.

Magnetic resonance imaging of pilocytic astrocytomas: usefulness of the minimum apparent diffusion coefficient (ADC) value for differentiation from high-grade gliomas.

BACKGROUND: On contrast-enhanced magnetic resonance (MR) images, pilocytic astrocytomas (PAs) are usually well-enhanced tumors that may mimic high-grade gliomas (HGGs). On the other hand, it has been suggested that areas exhibiting minimum apparent diffusion coefficient (ADC) values reflect the sites of highest cellularity within heterogeneous tumors. PURPOSE: To test the hypothesis that the cellularity of PAs is significantly different to the cellularity of HGGs, which should result in significant differences in minimum ADC values. MATERIAL AND METHODS: Between 1999 and 2005, 15 patients (nine males, six females) with histopathologically confirmed PAs underwent pretreatment MR examination including diffusion-weighted (DW) imaging. We reviewed their MR findings with respect to the size, location, morphology, contrast enhancement, and minimum ADC value of the tumors. The minimum ADC values of the 15 PAs were compared with those of 104 HGGs diagnosed during the same period. RESULTS: The diameter of the 15 PAs ranged from 11 to 60 mm (mean 36 mm); all were located around the ventricles, and all contained enhancing components. All except two small (11 and 14 mm) PAs contained cystic components. The minimum ADC values were significantly higher in PAs (median 1.688, range 1.375-1.897 x 10(-3) mm(2)/s) than HGGs (0.997, 0.543-2.024 x 10(-3) mm(2)/s) (P < 0.0001), although there was substantial overlap. Among the tumors with enhancing components, all but one PA were differentiated from the 76 HGGs with enhancing components (0.922, 0.543-1.462 x 10(-3) mm(2)/s) when the minimum ADC cutoff value was set at 1.5 x 10(-3) mm(2)/s. CONCLUSION: The minimum ADC value may be helpful for the differentiation between PAs and HGGs. A tumor with enhancing components should be PA instead of HGG when the minimum ADC value is higher than 1.5 x 10(-3) mm(2)/s.

Differentiation between paraclinoid and cavernous sinus aneurysms with contrast-enhanced 3D constructive interference in steady- state MR imaging.

BACKGROUND AND PURPOSE: Differentiation between paraclinoid and cavernous sinus aneurysms of the internal carotid artery (ICA) is critical when considering treatment options. The purpose of this study was to determine whether contrast-enhanced (CE) 3D constructive interference in steady state (CISS) MR imaging is useful to differentiate between paraclinoid and cavernous sinus aneurysms. MATERIALS AND METHODS: This study included 11 aneurysms in 10 consecutive female patients, ranging from 52 to 66 years of age. All aneurysms were adjacent to the anterior clinoid process. After conventional and CE 3D-CISS imaging on a 1.5T MR imaging unit, all patients underwent surgery, and the relationship between the aneurysms and the dura was confirmed. Two neuroradiologists evaluated the location of the aneurysms on CE 3D-CISS images and classified them as intradural, partially intradural, and extradural aneurysms. Operative findings were used as a reference standard. To understand the imaging characteristics, we assessed the boundary and signal intensity of the cavernous sinus, CSF, and carotid artery on the side contralateral to the lesion. RESULTS: Operative findings disclosed that 5 aneurysms were intradural and 6 were extradural. All except 2 were accurately assessed with CE 3D-CISS imaging. One intradural aneurysm adjacent to a large cavernous aneurysm and 1 cavernous giant aneurysm were assessed as partially intradural. On CE 3D-CISS images, the boundary between the CSF, cavernous sinus, and carotid artery was identified by high signal-intensity contrast in all cases. CONCLUSION: CE 3D-CISS MR imaging is useful for the differentiation between paraclinoid and cavernous sinus aneurysms.

Attempts to purify hemopoietic stem cell enrichment in bone marrow by use of glass wool filtration.

This study is about enrichment of hemopoietic stem cell concentration in mouse bone marrow by use of a glass wool filtration technique. Maximum stem cell concentration was accomplished when filtration conditions were as follows: (1) support medium supplemented to 15% with fresh serum from syngeneic donors; (2) no incubation time allowed for cells on the columns; and (3) an operational temperature of 24 degrees C. With these conditions, stem cell concentrations were increased 5,4-fold relative to the concentration in untreated marrow.

Specific and nonspecific stimulation of resistance to the growth and metastasis of the line 1 lung carcinoma.

The effects of specific dead tumor cell immunization and nonspecific immunostimulation with Corynebacterium parvum on the s.c. growth of the line 1 carcinoma in syngeneic BALB/c mice have been studied. Injection of heavily irradiated line ) carcinoma cells did not inhibit the transplantability or growth of the line 1 carcinoma, and in certain cases these treatments actually prolonged the period of rapid growth. This latter observation was traced to a mild inhibition of metastatic spread, which itself can slow the s.c. tumor growth. Treatment of the mice with 0.25 mg of C. parvum 7 days prior to transplant of the tumor had no effect on its growth by itself; but in combination with i.v.-injected tumor cells, which themselves had no effect on tumor growth, a 45% inhibition of tumor growth was induced. These data demonstrate that, in the weekly immunogenic line 1 carcinoma system, inhibition of s.c. transplants requires not only exposure to tumor antigens but also stimulation of the immunological reactivity.

Secondary disease mortality in rat-mouse radiation chimeras.

Two statistical experimental designs were used to investigate factors involved in 90-day mortality from secondary disease in lethally irradiated mice treated with rat bone marrow. Secondary disease is a graft-versus-host syndrome that has a mortality of about 65-95% in this transplant situation. When the factors--age-of-donor-cells, day-of-cell-injection, dose-of-marrow-cells, sex, and environment--were examined for their main effects and interactions, some combinations of these factors were found to give about 25% 90-day mortality. The experiments indicate that the lowest mortality can be achieved with an injection of 40 million or more cells 1 day after irradiation and an ultraclean environment of unlimited filter-top caging.