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141.
PURPOSE: It has been hypothesized that tumors with high interstitial fluid pressure (IFP) and/or hypoxia respond poorly to chemotherapy (CT) because of poor drug delivery. Preclinical studies have shown that paclitaxel reduces the IFP and improves the oxygenation (pO(2)) of tumors. Our aim is to evaluate the IFP and pO(2) before and after neoadjuvant CT using sequential paclitaxel and doxorubicin in patients with breast cancer tumors of >/= 3 cm. PATIENTS AND METHODS: Patients were randomly assigned, according to an institutional review board-approved phase II protocol, to receive neoadjuvant sequential CT consisting of either four cycles of dose-dense doxorubicin at 60 mg/m(2) every 2 weeks followed by nine cycles of weekly paclitaxel at 80 mg/m(2) (group 1) or vice versa, with paclitaxel administered before doxorubicin (group 2). Patients were re-evaluated clinically and radiologically. The IFP (wick-in-needle technique) and pO(2) (Eppendorf) were measured in tumors at baseline and after completing the administration of the first and second drug. RESULTS: IFP and pO(2) were measured in 54 patients at baseline and after the first CT. Twenty-nine and 25 patients were randomly assigned to groups 1 and 2, respectively. Paclitaxel, when administered first, decreased the mean IFP by 36% (P = .02) and improved the tumor pO(2) by almost 100% (P = .003). In contrast, doxorubicin did not have a significant effect on either parameter. This difference was independent of the tumor size or response measured by ultrasound. CONCLUSION: Paclitaxel significantly decreased the IFP and increased the pO(2), whereas doxorubicin did not cause any significant changes. Tumor physiology could potentially be used to optimize the sequence of neoadjuvant CT in breast cancer.  相似文献   
142.
PURPOSE: To test the ability of the cytoprotectant, amifostine, to reduce chemoradiotherapy-induced esophagitis and evaluate its influence on quality of life (QOL) and swallowing symptoms. PATIENTS AND METHODS: A total of 243 patients with stage II to IIIA/B non-small-cell lung cancer received induction paclitaxel 225 mg/m(2) intravenously (IV) days 1 and 22 and carboplatin area under the curve (AUC) days 1 and 22, followed by concurrent weekly paclitaxel (50 mg/m(2) IV) and carboplatin (AUC 2), and hyperfractionated radiation therapy (69.6 Gy at 1.2 Gy bid). Patients were randomly assigned at registration to amifostine (AM) 500 mg IV four times per week or no AM during chemoradiotherapy. Beyond standard toxicity end points, physician dysphagia logs (PDLs), daily patient swallowing diaries, and QOL (EORTC QLQ-C30/LC-13) were also collected. Swallowing AUC analyses were calculated from patient diaries and PDLs. RESULTS: A total of 120 patients were randomly assigned to receive AM, and 122, to receive no AM (one patient was ineligible); 72% received AM per protocol or with a minor deviation. AM was associated with higher rates of acute nausea (P = .03), vomiting (P = .007), cardiovascular toxicity (P = .0001), and infection or febrile neutropenia (P = .03). The rate of >/= grade 3 esophagitis was 30% with AM versus 34% without AM (P = .9). Patient diaries demonstrated lower swallowing dysfunction AUC with amifostine (z test P = .025). QOL was not significantly different between the two arms, except for pain, which showed more clinically meaningful improvement and less deterioration at 6 weeks follow-up (v pretreatment) in the AM arm (P = .003). The median survival rates for both arms were comparable (AM, 17.3 v no AM, 17.9 months; P = .87). CONCLUSION: AM did not significantly reduce esophagitis >/= grade 3 in patients receiving hyperfractionated radiation and chemotherapy. However, patient self-assessments suggested a possible advantage to AM that is being explored with modified dosing route strategies.  相似文献   
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The aim of the present study was to assess the feasibility of a portable gamma camera (PGC) for guiding surgical treatment in locally advanced breast cancer (LABC) after neoadjuvant therapy (NT). Since January 2012, a PGC (Sentinella 102, ONCOVISION) has been available in our center. We planned to perform a feasibility monocentric prospective study involving 15–20 patients with LABC for assessing the diagnostic performance of this PGC after NT (Breast Cancer Surgery-S102). Before the surgical treatment and at the end of NT an injection of 99mTc-Sestamibi (100–150 MBq) was made. Conventional scintimmamography (SMM) and Sentinella 102 images were obtained from 18 patients. 10 (55.5 %) patients showed a focal uptake of tracer in the breast or lymph nodes before or after the surgical excision (on histological specimen), while 8 did not. The histological specimen concluded for a complete response to NT in 4 (22.2 %) patients and for a partial or no response to treatment in the remnant 14 subjects. The specificity and false-negative rate of the Sentinella 102 compared to SMM were 100 % for both and 38 % vs. 60 %, respectively. The global diagnostic accuracy of Sentinella 102 was: 66.7 % (95 % confidence interval: 44.88–88.44 %). The present feasibility study shows how a new nuclear imaging device can be useful in the operating theatre for guiding a radical surgery approach in patients with LABC after NT.  相似文献   
147.
The aim of this study was to evaluate the change of breast density in the normal breast of patients receiving neoadjuvant chemotherapy (NAC). Forty‐four breast cancer patients were studied. MRI acquisition was performed before treatment (baseline), and 4 and 12 weeks after treatment. A computer‐algorithm‐based program was used to segment breast tissue and calculate breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) (the ratio of FV over BV × 100%). The reduction of FV and PD after treatment was compared with baseline using paired t‐tests with a Bonferroni–Holm correction. The association of density reduction with age was analyzed. FV and PD after NAC showed significant decreases compared with the baseline. FV was 110.0 ml (67.2, 189.8) (geometric mean (interquartile range)) at baseline, 104.3 ml (66.6, 164.4) after 4 weeks (p < 0.0001), and 94.7 ml (60.2, 144.4) after 12 weeks (comparison with baseline, p < 0.0001; comparison with 4 weeks, p = 0.016). PD was 11.2% (6.4, 22.4) at baseline, 10.6% (6.6, 20.3) after 4 weeks (p < 0.0001), and 9.7% (6.2, 17.9) after 12 weeks (comparison with baseline, p = 0.0001; comparison with 4 weeks, p = 0.018). Younger patients tended to show a higher density reduction, but overall correlation with age was only moderate (r = 0.28 for FV, p = 0.07, and r = 0.52 for PD, p = 0.0003). Our study showed that breast density measured from MR images acquired at 3T MR can be accurately quantified using a robust computer‐aided algorithm based on non‐parametric non‐uniformity normalization (N3) and an adaptive fuzzy C‐means algorithm. Similar to doxorubicin and cyclophosphamide regimens, the taxane‐based NAC regimen also caused density atrophy in the normal breast and showed reduction in FV and PD. The effect of breast density reduction was age related and duration related. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
148.
Word and nonword reading ability was tested in a group of 11 patients with varying levels of language impairments. For the least impaired patients, the probability of grapheme-phoneme association affected nonword reading ability. An advantage reading nonwords that sound like words (pseudohomophones) was found for six patients, and was unrelated to the severity of patients' nonlexical reading impairments. All patients showed evidence of impairment to all three processing components hypothesised to be necessary for nonlexical reading. A focused study of the phonological processing abilities of the five subjects with mildest impairment uncovered differential influences of segment size and lexicality on patients' ability to combine aurally-presented sound segments. Results are interpreted as indicating multiple sources of impairment to a number of cognitive operations that are specialised to support nonlexical reading.  相似文献   
149.
We describe the single word reading impairment of a patient with severe acquired alexia in the context of largely spared auditory-verbal language. DES shows strong effects of lexical variables when reading words; she is completely unable to read nonwords. Her “visual” reading errors (orthographically related word substitutions) reflect a strong positional bias to differ from targets toward their right sides; this positional bias was evident across several different topographic transformations of the stimuli and was present in her spelling errors. Such a pattern of positional letter retention is commonly associated with right “neglect dyslexia” and has been interpreted as indicating damage to a spatially encoded word representation. However, DES shows no sign of spatial impairment in nonlanguage tasks, fails to demonstrate several of the characteristics thought to be diagnostic of “neglect dyslexia,” and shows no evidence of neglect in sentence reading. In contrast to the spatial account, we interpret DES's primary impairment as one involving a prelexical, transient level of representation in which letter order is coded abstractly (i.e. neither spatially nor serially).  相似文献   
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