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81.
BACKGROUND: When found in an otherwise benign biopsy, lobular carcinoma in situ (LCIS) has been associated with an increased risk of development of a subsequent invasive breast carcinoma. However, the association between LCIS and the risk of subsequent local recurrence in patients with infiltrating carcinoma treated with conservative surgery and radiation therapy has received relatively little attention. METHODS: Between 1968 and 1986, 1625 patients with clinical Stage I-II invasive breast carcinoma were treated at the Joint Center for Radiation Therapy at Harvard Medical School with breast-conserving surgery (CS) and radiation therapy (RT) to a total dose to the primary site of > or =60 grays. Analysis was limited to 1181 patients with infiltrating ductal carcinoma, infiltrating lobular carcinoma, or infiltrating carcinoma with mixed ductal and lobular features who, on review of their histologic slides, had sufficient normal tissue adjacent to the tumor to evaluate for the presence of LCIS and also had a minimum potential follow-up time of 8 years. The median follow-up time was 161 months. RESULTS: One hundred thirty-seven patients (12%) had LCIS either within the tumor or in the macroscopically normal adjacent tissue. The 8-year crude risk of recurrence was not significantly increased for patients with LCIS associated with invasive ductal, invasive lobular, or mixed ductal and lobular carcinoma. Among the 119 patients with associated LCIS adjacent to the tumor, the 8-year rate of local recurrence was 13%, compared with 12% for the 1062 patients without associated LCIS. For the 70 patients with moderate or marked LCIS adjacent to the tumor, the 8-year rate of local recurrence was 13%. The extent of LCIS did not affect the risk of recurrence. The risks of contralateral disease and of distant failure were similarly not affected by the presence or extent of LCIS. CONCLUSIONS: Breast-conserving therapy involving limited surgery and radiation therapy is an appropriate method of treating patients with invasive breast carcinoma with or without associated LCIS. Neither the presence nor the extent of LCIS should influence management decisions regarding patients with invasive breast carcinoma. [See editorial counterpoint and reply to counterpoint on pages 978-81 and 982-3, this issue.] Copyright 2000 American Cancer Society.  相似文献   
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83.
PURPOSE: Many authors have studied the problems associated with the three-field breast treatment, yet the proposed solutions present their own difficulties. This study presents a technique that overcomes these difficulties, reduces scatter to the contralateral breast, and improves setup reproducibility. METHODS AND MATERIALS: Patients are set up with both arms raised superiorly on a breast board. A precise field-match is achieved by rotating the couch and collimator of the tangents, while the supraclavicular field is half-beam blocked using an independent jaw. The posterior borders of the tangents are conformally defined by multileaf collimation. Measurements were performed to verify the field matching and evaluate scatter doses. RESULT: A smooth dose transition was found at the match line at all depths. Corner blocks and lower wedges were not used, which reduced the scatter to the contralateral breast compared with our prior technique. CONCLUSION: The technique achieves a precise match while removing constraints on the tangents' length and decreasing scatter dose. Procedures for simulation, planning, and treatment have been devised, along with a new patient setup routine incorporating orthogonal setup films and tattoos. This technique has been successfully implemented in routine treatment since September 2001. A program calculating the setup parameters is available at our website.  相似文献   
84.
The tumor suppressor phosphatase and tensin homologue deleted from chromosome 10 (PTEN) gene is a negative regulator of the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt/PKB) signaling pathway. Overexpression of PTEN in cancer cells results in cell-cycle arrest and cell death through inhibition of PI3K. Caffeine, a xanthine analogue, is well known to enhance the cytocidal and growth-inhibitory effects of DNA-damaging agents such as radiation, UV light, and anticancer agents on tumor cells by abrogating DNA-damage checkpoints through inhibition of ataxia-telangiectasia-mutated (ATM), and ATM and Rad3-related (ATR) kinase activity. In this study, we demonstrate that treatment with a combination of adenovirus-mediated transfer of PTEN (Ad-PTEN) and caffeine synergistically suppressed cell growth and induced apoptosis in colorectal cancer cells but not in normal colorectal fibroblast cells. This synergistic effect was induced through abrogation of G(2)/M arrest, downregulation of the Akt pathway, and modulation of the p44/42MAPK pathway. Thus, combined treatment with Ad-PTEN and caffeine is a potential therapy for colorectal cancer.  相似文献   
85.
Fluoroquinolones are one class of antimicrobial agents commonly used to treat severe Campylobacter jejuni infection. C. jejuni strains resistant to high levels of the fluoroquinolone ciprofloxacin (MIC >/=16 microg/ml) have been predominantly characterized with a C-->T transition in codon 86 of gyrA. The gyrA gene encodes one subunit of DNA gyrase, which is a primary target for fluoroquinolone antibiotics. This study establishes a rapid PCR-based TaqMan method for identifying ciprofloxacin-resistant C. jejuni strains that carry the C-->T transition in codon 86 of gyrA. The assay uses real-time detection, eliminating the need for gel electrophoresis. Optimization of the assay parameters using purified Campylobacter DNA resulted in the ability to detect femtogram levels of DNA. The method should be useful for monitoring the development of ciprofloxacin resistance in C. jejuni. Compiled nucleotide sequence data on the quinolone resistance-determining region of gyrA in Campylobacter indicate that sequence comparison of this region is a useful method for tentative identification of Campylobacter isolates at the species level.  相似文献   
86.
We have made anti-idiotypic antibodies in rabbits against three mouse monoclonal neutralizing antibodies with specificities for independent epitopes on Coxsackievirus B4. Each of these anti-idiotypic antibodies was found to react specifically with the immunizing monoclonal antibody in radioimmunoassays and did not react with the other monoclonal antibodies. In addition, the anti-idiotypic antibodies specifically inhibited the function (i.e., virus neutralization) of the immunizing antibody. These anti-idiotypic antibodies were tested for their ability to recognize receptors for Coxsackievirus B4 as measured by their ability to inhibit the attachment of radiolabeled virus to cellular receptors. The anti-idiotypic antibodies did not block the binding of Coxsackievirus B4 to monkey kidney cells. Moreover, when tested for their ability to bind to other receptor positive cells, none of the anti-idiotypic antibodies bound above control levels. Anti-idiotypic antibodies did induce a small anti-anti-idiotypic antibody response in mice when tested by radioimmunoassay; however, little if any virus neutralizing activity was found in the sera of these mice. Our results contrast to those reported for anti-idiotypic antibodies in several other virus systems and suggest that not all anti-idiotypic antibodies made against neutralizing antibodies are capable of eliciting an antiviral immune response or binding to viral viral receptors on cells.  相似文献   
87.
The present experiments were initiated to see if cells capable of binding antigens could make polyreactive antibodies. Fluorescein isothiocyanate-labeled self and non-self antigens were incubated with B cells from normal individuals. Antigenbinding cells were separated from non-antigen-binding cells by flow cytometry, immortalized with Epstein-Barr virus and analyzed at the clonal level for their capacity to make polyreactive antibodies. Four to six times more cells making polyreactive antibodies were found in the B cell subset that bound antigens than in the B cell subset that did not bind antigens. The majority of the polyreactive antibodies were of the immunoglobulin (Ig)M isotype. Immunoflow cytometry revealed that cell lines making polyreactive antibodies bound a variety of antigens (e.g., insulin, IgGFc and β-galactosidase), whereas cell lines making monoreactive antibodies bound only a single antigen. The binding of antigens to B cell lines that made polyreactive antibodies could be inhibited (range, 28%–57%) by both homogeneous and heterogeneous antigens. Both CD5+ and CD5? antigen-binding B cells made polyreactive antibodies, but the frequency was slightly higher in the CD5+ antigen-binding (85%) as compared to the CD5? antigen-binding (50%) population. Comparison of CD5+ B cells that bound antigens with CD5+ B cells that did not bind antigens showed that approximately 86% of the former, but only 15% of the latter, made polyreactive antibodies. It is concluded that cells capable of binding a variety of different antigens can make polyreactive antibodies and that antigen binding is a good marker for identifying polyreactive antibody-producing cells.  相似文献   
88.
1. Infected material from the brain and spinal cord of an infant suffering from a recently recognized form of granulomatous encephalomyelitis was inoculated into rabbits and mice and produced an experimental disease which was readily transmissible in series. 2. A parasite identical with that in the lesions of the human case was found in the lesions of the experimental animals. 3. The morphology of this microorganism, the course of the disease and the lesions produced in the animals inoculated with it, the wide host range of this parasite, and the results of cross immunity experiments, establish its identity as a Toxoplasma. It is suggested that the microorganism be designated Toxoplasma hominis. 4. The clinical and pathologic features of the infection produced in animals by this Toxoplasma are described. 5. The infection in the infant is the first proved instance of human toxoplasmosis. Since the lesions were confined to the central nervous system the disease is termed toxoplasmic encephalomyelitis. 6. The first experimental transmission of human toxoplasmosis to animals is recorded.  相似文献   
89.
Cases of syncope associated with exertional dyspnea and angina pectoris have been presented. Serveral of the common types of heart disease are included in the group.The patients described in remarkably the same manner the sequence of events leading to syncope. Syncope was always preceded by both exertional dyspnea and angina, and was prone to occur at times when congestive heart failure was most marked.Physical examination failed to reveal anything other than the usual features of the underlying disease. With one exception, carotid sinus stimulation and hyperventilation produced no abnormal responses.The various common types of cardiovascular syncope have been considered in connection with these patients. The cause of their syncope remains obscure, but it is suggested that exertion beyond the capacity of the cardiac output and reflexes arising from engorged lungs and an ischemic myocardium may be important factors.  相似文献   
90.
OBJECTIVE: To investigate the impact of 2 months of neoadjuvant and 2 months of concurrent hormonal therapy on the acute gastrointestinal (GI) toxicities associated with 3-dimensional conformal radiation therapy (3D-CRT) for prostate adenocarcinoma. METHODS: The study cohort consisted of 80 men who underwent 3D-CRT with (n=40) or without (n=40) neoadjuvant and concurrent hormonal therapy. Computerized tomography-based planning occurred after neoadjuvant hormonal therapy. All patients completed a previously validated, quality-of-life self-assessment tool on 7 GI symptoms, including diarrhea, urgency, pain, rectal bleeding, cramping, mucus, and tenesmus, at baseline and weekly during radiation therapy. RESULTS: Patients who received hormonal therapy were more likely to have T2b, T2c, T3a, or T3b (P<0.001) or Gleason score 7, 8, or 9 (P=0.02) disease compared to those that did not. The dose delivered to the planning target volume was 70 Gy for both groups. Median radiation treatment volume was numerically smaller for the hormone group but not to a statistically significant degree (949 vs. 1043 cc, P=0.30). Patients who received hormonal therapy had less rectal pain (P<0.01) and tenesmus (P=0.02) but more rectal mucus (P=0.03) compared to those who did not. CONCLUSIONS: Prostate gland volume reduction after androgen suppression therapy may reduce patient-reported acute GI toxicities associated with 3D-CRT for prostate cancer.  相似文献   
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