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1.

Purpose

This study aimed to prospectively characterize toxicity and cosmesis after accelerated partial breast irradiation (APBI) with 3-dimensional conformal radiation therapy (CRT) or single-entry, multilumen, intracavitary brachytherapy.

Methods and materials

A total of 281 patients with pTis, pT1N0, or pT2N0 (≤3.0 cm) breast cancer treated with segmental mastectomy were prospectively enrolled from December 2008 through August 2014. APBI was delivered using 3-dimensional CRT (n = 29) or with SAVI (n = 176), Contura (n = 56), or MammoSite (n = 20) brachytherapy catheters. Patients were evaluated at protocol-specified intervals, at which time the radiation oncologist scored cosmetic outcome, toxicities, and recurrence status using a standardized template.

Results

The median follow-up time is 41 months. Grade 1 seroma and fibrosis were more common with brachytherapy than with 3-dimensional CRT (50.4% vs 3.4% for seroma; P < .0001 and 66.3% vs 44.8% for fibrosis; P = .02), but grade 1 edema was more common with 3-dimensional CRT than with brachytherapy (17.2% vs 5.6%; P = .04). Grade 2 to 3 pain was more common with 3-dimensional CRT (17.2% vs 5.2%; P = .03). Actuarial 5-year rates of fair or poor radiation oncologist-reported cosmetic outcome were 9% for 3-dimensional CRT and 24% for brachytherapy (P = .13). Brachytherapy was significantly associated with inferior cosmesis on mixed model analysis (P = .003). Significant predictors of reduced risk of adverse cosmetic outcome after brachytherapy were D0.1cc (skin) ≤102%, minimum skin distance >5.1 mm, dose homogeneity index >0.54, and volume of nonconformance ≤0.89 cc. The 5-year ipsilateral breast recurrence was 4.3% for brachytherapy and 4.2% for 3-dimensional CRT APBI patients (P = .95).

Conclusions

Brachytherapy APBI is associated with higher rates of grade 1 fibrosis and seroma than 3-dimensional CRT but lower rates of grade 1 edema and grade 2 to 3 pain than 3-dimensional CRT. Rates of radiation oncologist-reported fair or poor cosmetic outcomes are higher with brachytherapy. We identified dosimetric parameters that predict reduced risk of adverse cosmetic outcome after brachytherapy-based APBI. Ipsilateral breast recurrence was equivalent for brachytherapy and 3-dimensional CRT.  相似文献   
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4.

Purpose

There is little information in the literature on health-related quality of life (HRQOL) changes due to high-dose-rate (HDR) brachytherapy monotherapy for prostate cancer.

Materials and Methods

We conducted a prospective study of HRQOL changes due to HDR brachytherapy monotherapy for low risk or favorable intermediate risk prostate cancer. Sixty-four of 84 (76%) patients who were treated between February 2011 and April 2013 completed 50 questions comprising the Expanded Prostate Cancer Index Composite (EPIC) before treatment and 6 and/or 12 months after treatment.

Results

Six months after treatment, there was a significant decrease (p<0.05) in EPIC urinary, bowel, and sexual scores, including urinary overall, urinary function, urinary bother, urinary irritative, bowel overall, bowel bother, sexual overall, and sexual bother scores. By one year after treatment, EPIC urinary, bowel, and sexual scores had increased and only the bowel overall and bowel bother scores remained significantly below baseline values.

Conclusions

HDR brachytherapy monotherapy is well-tolerated in patients with low and favorable intermediate risk prostate cancer. EPIC urinary and sexual domain scores returned to close to baseline 12 months after HDR brachytherapy.  相似文献   
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Is transplantation tolerable?   总被引:1,自引:0,他引:1       下载免费PDF全文
To test the hypothesis that chronic stimulation of T cells with a weak agonistic antigen will generate regulatory T cells and immune tolerance, a study reported in this issue employed the redesign of a minor histocompatibility antigen. Using knowledge of residues at which the antigen contacts the T cell receptor, a weak agonist was produced. Pretreatment with this altered antigen produced transplant tolerance, generation of regulatory T cells, and a loss of many antigen-reactive T cells.  相似文献   
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The expression of HLA-DR (a class II histocompatibility antigen) on monocytes isolated from the peripheral blood of normal individuals and patients with acquired immune deficiency syndrome (AIDS) was investigated by the use of dual fluorescent staining and cytofluorometry. In animal models the absence of class II positive monocytes is linked to a failure of T cells to respond to antigens. We now report that patients with AIDS have a paucity of HLA-DR+ monocytes. The percentage of HLA-DR+ monocytes among eight normal individuals ranged from 49.3 to 95.0%+, and only one individual had less than 50% HLA-DR+ monocytes. HLA-DR expression on monocytes from homosexual male patients with lymphadenopathy was similar to that of normal subjects (range, 58.0 to 97.4%+). In contrast, seven of nine patients with AIDS had less than 50% HLA-DR+ monocytes (range, 13.4 to 78.8%+). The in vitro incubation of monocytes from AIDS patients with cloned human interferon-gamma resulted in an increase of the expression of HLA-DR to near normal levels.  相似文献   
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Nur77 and its family members Nurr1 and Nor-1 are inducible orphan nuclear receptors that orchestrate cellular responses to diverse extracellular signals. In epithelia, Nur77 can act as a potent proapoptotic molecule in response to cellular stress, suggesting a possible role for this nuclear receptor in the tissue response to injury. Here, we found that Nur77 promotes epithelial cell apoptosis after AKI. Injury of proximal tubular epithelial cells rapidly and strongly induced Nur77, Nor-1, and Nurr1 both in vitro and in vivo. After renal ischemia-reperfusion, Nurr77-deficient mice exhibited less apoptosis of tubular epithelial cells and better renal function than wild-type mice. Nur77-mediated renal injury involved a conformational change of Bcl2 and an increase in the protein levels of proapoptotic Bcl-xS. Ligand-activated retinoic acid receptors repressed Nur77 induction and function. Pretreatment of wild-type mice with retinoic acid before renal ischemia-reperfusion blunted the induction of Nur77, conferred protection of renal function, attenuated renal histologic injury, and reduced the expression of epithelial-derived proinflammatory cytokines. Retinoic acid also inhibited hypoxia-mediated induction of proinflammatory cytokines in cultured renal epithelial cells. Results obtained from proximal tubule cultures derived from Nur77-deficient mice suggested that the inhibition of Nur77 expression mediated the renoprotective effects of retinoic acid. In summary, Nur77 promotes epithelial apoptosis after ischemia-reperfusion injury, and retinoic acid-mediated inhibition of Nur77 expression is a promising therapeutic strategy for the prevention of AKI.  相似文献   
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