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91.
Sarcoidosis is generally not considered in the differential diagnosis of solitary pulmonary nodules. We recently encountered a case in which preoperative awareness of this presentation of sarcoidosis allowed a limited pulmonary resection with resultant lower morbidity and potential preservation of lung function to be performed. Although rare, sarcoidosis should be considered in the differential diagnosis of solitary pulmonary nodules. 相似文献
92.
Understanding diet and energy balance as risk factors for breast, colon,
and other cancers requires information on the contribution of each factor
and of interactions among factors to cancer risk. Rodent models for breast
cancer provide extensive data on effects of dietary fat and calories,
energy balance, body weight gain, and physical activity on tumor
development. Analyses of the combined data from many studies have shown
clearly that quality and quantity of dietary fat and energy balance
contribute independently to increased mammary gland tumorigenesis. These
findings were seen in female rats fed diets high in fat (35-40% of
calories) compared to rats fed control diets, with approximately 10% of
calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46,
215-223). The methods used permit comparison of experimental and
epidemiological data, and they may be useful in extrapolating between
species and developing public health recommendations. In addition to the
contributions of lifetime-diet composition, intake, energy balance, and
physical activity to cancer risk, there are questions about the timing and
duration of alterations in these factors and about the "dose-response"
characteristics of cancer risk to the factors. Endocrine mechanisms may be
significant in mammary gland tumor risk, but experimental and
epidemiological data indicate that cancers at other sites, such as colon
and liver, also are influenced by the factors listed. Other diet and
lifestyle factors that influence energy, or specifically fat, metabolism
may also affect risk for cancers that are promoted by increased intake of
fat and calories. Studies of separate and interactive effects of dietary
fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et
al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using
adjustment of carcinogenesis endpoints for body weight, tumor burden, and
latency, they were found to be related to weight gain within treatment
groups in 2 of 3 experiments.
相似文献
93.
Smitt MC Stouffer N Owen JB Hoppe RT Hanks GE 《International journal of radiation oncology, biology, physics》1999,43(2):335-339
PURPOSE: To document national standards of care for patients receiving radiotherapy as part of curative treatment for Hodgkin's disease. MATERIALS AND METHODS: A national survey was conducted of 61 institutions treating 275 patients with Stages I-III Hodgkin's disease and representing six facility type strata. Pretreatment evaluation, radiotherapy treatment parameters, and use of combined modality therapy were assessed. RESULTS: Ann Arbor stage for the 275 patients was as follows: IA, 69 (25%); IB, 7 (3%); IIA, 123 (45%); IIB, 36 (13%); IIIA 23 (8%), IIIB, 14 (5%); unknown, 3 (1%). Pretreatment evaluation included complete blood count for 93%, sedimentation rate in 29%, chest CT in 88%, abdominal CT scan in 87%, and bone marrow biopsy in 81%. Lymphangiograms were obtained in 50% of cases; laparotomy was performed in 46%. The yield of positive findings in the spleen at laparotomy was 6.5 % overall. Facility differences with respect to staging were seen only for the use of gallium scans, which were more commonly used in academic centers (44% vs. 15-23% elsewhere, p<0.001). Radiotherapy was delivered with a linear accelerator in 94% of cases. Treatment simulation was performed for 94% and individualized blocks constructed for 95% overall; however, freestanding facilities had a lower rate of performance of these procedures (78% vs. 98-99% for simulation and 88% vs. 96-99% for customized blocking, p<0.001). The mean supradiaphragmatic dose was 36.74 Gy and the mean subdiaphragmatic dose was 33.81 Gy. Planned combined modality therapy was given in 36% of patients. The use of combined modality therapy by stage was as follows: IA, 11%; IB, 43%; IIA, 30%; IIB, 68%; IIIA, 57%; IIIB, 100%. Chemotherapy was completed prior to radiation in 80% of cases and generally consisted of ABVD (32%), an alternating regimen (25%), or MOPP (22%). Among Stage I/II patients, use of chemotherapy was associated with reduced radiation doses (mean supradiaphragmatic dose 34.53 Gy vs. 38.43 Gy and mean subdiaphragmatic dose 31.27 Gy vs. 34.51 Gy), and reduced volumes of treatment (87% vs. 28% treated to one side of the diaphragm only). Laparotomy was not associated with decreased supra- or subdiaphragmatic radiation doses or decreased volumes of treatment. CONCLUSIONS: With the exception of gallium scans, pretreatment evaluation is relatively uniform across facility strata. Increased understanding of prognostic factors in Hodgkin's disease and greater use of planned combined modality therapy for higher risk patients appears to have contributed to a decreased use of and low yield of positive findings for laparotomy. Laparotomy was not associated with reduced radiation volumes or doses. Freestanding radiation facilities had a lower rate than other facility types for the performance of treatment simulation and customized patient blocking. 相似文献
94.
We reviewed our institution's experience treating patients with prostate cancer with 3-dimensional conformal radiation therapy (3DCRT) and short-term adjuvant hormonal therapy to determine biochemical no evidence of disease (bNED) and clinical outcome compared with patients treated with 3DCRT alone. Between 4/1/89 and 11/30/94, 558 patients with clinically localized prostate cancer received treatment at Fox Chase Cancer Center (Philadelphia, Pa.); 484 patients were treated with 3DCRT alone (Group I); 74 patients were treated with 3DCRT and hormones (Group II). Five-year actuarial rates of bNED control, distant metastasis-free survival (DMFS), cause-specific survival (CSS), and overall survival (OS) were calculated for pretreatment PSA, Gleason score, T stage, use of hormones, treatment field size, age, and dose. A matched case/control analysis was performed to further evaluate the effect of hormones on treatment with 3DCRT. Median follow-up was 47 months (range: 2-97 months). The 5-year actuarial rates of bNED control, DMFS, CSS, and OS were 66%, 93%, 98%, and 86%, respectively, for Group I patients and 68%, 93%, 98%, and 89%, respectively, for Group II patients. Multivariate analysis demonstrated that hormone use was an independent predictor of bNED control only. A significant difference in bNED control was observed between Group I and II (43% vs. 71%) using the matched case/control analysis (P = 0.02). A trend towards significance was observed for different rates of DMFS between Group I and II (79% vs. 94%, P = 0.09). Patients with clinically localized prostate cancer with poor prognostic features (pretreatment PSA > or = 10 ng/ml, Gleason score > or = 7, and/or T2c or greater palpation stage) show improved rates of bNED control and a trend towards improved DMFS when treated with 3DCRT and short-term adjuvant hormones compared with 3DCRT alone. Long-term observation will be necessary to see if improvements in bNED control will translate into improvements in overall survival. 相似文献
95.
Heather Hanks P Craig Veitch Mark F. Harris 《The Australian journal of rural health》2008,16(6):376-382
Objective: To identify and compare the roles of urban, rural and remote general practitioners (GPs) in colorectal cancer (CRC) management. Design: Semistructured interviews exploring GP views of their role in CRC management. Setting: Urban, rural and remote general practices in north Queensland. Participants: Fifteen GPs in urban, rural and remote practice. Main outcome measures: Self‐reported roles in the management of CRC patients and factors influencing these roles. Results: All GPs, regardless of location of practice, played a role in diagnosis, referral, postoperative care, psychosocial counselling, follow up and palliative care. Involvement in treatment of CRC patients was only performed by remote GPs. In general, rural and remote GPs played greater roles in care coordination, clinical and psychosocial care. Rural and remote GPs were more heavily involved throughout the entire illness progression when compared with their urban counterparts. Conclusions: The results of this study indicate that rural and remote GPs in north Queensland play a greater role than urban GPs in the management of CRC. In order to maintain and enhance the roles of rural and remote GPs in CRC care, appropriate guidelines and remuneration should be provided. Palliative care support might also be useful to rural and remote GPs. 相似文献
96.
A comparison of the cost of various treatment methods for early cancer of the prostate 总被引:1,自引:0,他引:1
G E Hanks K Dunlap 《International journal of radiation oncology, biology, physics》1986,12(10):1879-1881
The relative costs have been determined for treating prostate cancer by radical prostatectomy, lymph node dissection with I125 implant, and external beam radiation in a large community practice. About 15% of patients were treated with the options involving surgery. The median cost of radical prostatectomy was $14,400, lymph dose dissection and I125 implant $12,000, and external beam radiation $6750 prior to October 1984 and $5600 after October 1984. None of the data indicate superior outcome by any one of these methods for Stage A or B prostate cancer. Therefore, the surgical approaches are usually not recommended except for the patient highly motivated to maintain potency who may select the I125 implant. In an era of diminishing funds for health care, the federal government, industry, and perceptive HMO's may elect to pay only for the less expensive method. 相似文献
97.
Meniscal injuries: detection using MR imaging 总被引:15,自引:0,他引:15
Reicher MA; Hartzman S; Duckwiler GR; Bassett LW; Anderson LJ; Gold RH 《Radiology》1986,159(3):753-757
Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears. 相似文献
98.
99.
100.
Chlorpropamide-induced pure white cell aplasia 总被引:2,自引:0,他引:2
We investigated the mechanism for isolated agranulocytosis and marrow pure white cell aplasia in an elderly man receiving 0.5 to 1.0 g per day of chlorpropamide (Chl) without other toxic drug exposure or overt systemic illness. Patient marrow revealed an absence of recognizable granulocytic precursors; megakaryocytes and erythroid precursors were normal. The WBC count was 1800/mm3 on admission with only 2% neutrophils; the absolute neutrophil count first exceeded 500/mm3 on the 17th day following cessation of Chl. A serum Chl level on admission was 100 micrograms/mL (acute phase, AP); no Chl was detected in serum (convalescent phase, CP) assessed on the 22nd hospital day. Antineutrophil antibodies were not detected, and T cell depletion failed to augment patient in vitro granulopoiesis. Patient AP serum produced potent complement-mediated inhibition (87% +/- 7%) of autologous granulocyte progenitors (CFU-GM) with minimal inhibition of erythroid (11% +/- 5%) or multipotent (5% +/- 4%) progenitor cells. Selective inhibition by patient AP serum of CFU-GM (74% +/- 11%) was also seen against two allogeneic marrows. Patient CP serum no longer inhibited (6% +/- 4%) autologous CFU-GM. Addition of Chl (5 to 120 micrograms/mL) to CP serum but not to control serum resulted in potent drug concentration-dependent complement-mediated inhibition of autologous and allogeneic CFU-GM. Inhibition of CFU-GM in the presence of Chl was no longer demonstrable following immunoabsorbent removal of IgG from patient serum. Patient serum in the presence of Chl had limited activity against morphologically recognizable marrow granulocytic precursors in a microimmunofluorescence assay. These results are most consistent with the development of Chl-dependent, selective antibody-mediated immune inhibition of granulopoiesis. 相似文献