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41.
Cost-effectiveness of hepatic metastasectomy in patients with metastatic colorectal carcinoma: a state-transition Monte Carlo decision analysis 总被引:4,自引:0,他引:4 下载免费PDF全文
Gazelle GS Hunink MG Kuntz KM McMahon PM Halpern EF Beinfeld M Lester JS Tanabe KK Weinstein MC 《Annals of surgery》2003,237(4):544-555
OBJECTIVE: To evaluate the cost-effectiveness of hepatic resection ("metastasectomy") in patients with metachronous liver metastases from colorectal carcinoma (CRC), and to investigate the impact of operative and follow-up strategies on outcomes, cost, and cost-effectiveness. SUMMARY BACKGROUND DATA: There is substantial evidence that resection of CRC liver metastases can result in long-term survival in some patients. However, several unresolved issues are difficult to address using currently available clinical data. These include the appropriate threshold for resection, whether to perform repeat resection, and the relative cost-effectiveness of the procedure(s). METHODS: The authors developed a state-transition Monte Carlo decision model to evaluate the (societal) cost-effectiveness of hepatic metastasectomy in patients with metachronous CRC liver metastases. The model tracks the presence, number, size, location, growth, detection, and removal of up to 15 individual metastases in each patient. Survival, quality of life, and cost are predicted on the basis of disease extent. Imaging and surgery affect outcomes via detection and removal of individual metastases. Several patient management strategies were developed and compared with respect to cost, effectiveness, and incremental cost-effectiveness ($/quality-adjusted life year [QALY]). A reference strategy in which metastasectomy is not offered and imaging is not performed for the purpose of assessing resectability or operative planning ("no-surgery" strategy) was included for comparison. Extensive sensitivity analysis was performed to evaluate the impact of alternative model assumptions on results. RESULTS: A strategy permitting resection of up to six metastases and one repeat resection, with CT follow-up every 6 months, resulted in a gain of 2.63 QALYs relative to the no-test/no-treat strategy, at an incremental cost of 18,100 US dollars/QALY. When additional surgical strategies were considered, the incremental cost-effectiveness ratio (ICER; relative to the next least effective strategy) of the six metastases, one repeat, 6-month strategy was 31,700 US dollars/QALY. Across a range of model assumptions, more aggressive treatment strategies (i.e., resection of more metastases, resection of recurrent metastases) were superior to less aggressive strategies and had ICERs below 35,000 US dollars/QALY. Findings were insensitive to changes in most model parameters but somewhat sensitive to changes in surgery and treatment costs. CONCLUSIONS: Hepatic metastasectomy is a cost-effective option for selected patients with metachronous CRC metastases limited to the liver. When considering metastasectomy, more aggressive approaches are generally preferred to less aggressive approaches. Overall, surgeons should be encouraged to consider resection for all patients whose metastases can technically be removed. 相似文献
42.
Halpern SH Breen TW Campbell DC Muir HA Kronberg J Nunn R Fick GH 《Anesthesiology》2003,98(6):1431-1435
BACKGROUND: A meta-analysis of studies comparing high doses of bupivacaine with ropivacaine for labor pain found a higher incidence of forceps deliveries, motor block, and poorer neonatal outcome with bupivacaine. The purpose of this study was to determine if there is a difference in these outcomes when a low concentration of patient-controlled epidural bupivacaine combined with fentanyl is compared with ropivacaine combined with fentanyl. METHODS: This was a multicenter, randomized, controlled trial, including term, nulliparous women undergoing induction of labor. For the initiation of analgesia, patients were randomized to receive either 15 ml bupivacaine, 0.1%, or 15 ml ropivacaine, 0.1%, each with 5 microg/ml fentanyl. Analgesia was maintained with patient-controlled analgesia with either local anesthetic, 0.08%, with 2 microg/ml fentanyl. The primary outcome was the incidence of operative delivery. We also examined other obstetric, neonatal, and analgesic outcomes. RESULTS: There was no difference in the incidence of operative delivery between the two groups (148 of 276 bupivacaine recipients vs. 135 of 279 ropivacaine recipients; P = 0.25) or any obstetric or neonatal outcome. The incidence of motor block was significantly increased in the bupivacaine group compared with the ropivacaine group at 6 h (47 of 93 vs. 29 of 93, respectively; P = 0.006) and 10 h (29 of 47 vs. 16 of 41, respectively; P = 0.03) after injection. Satisfaction with mobility was higher with ropivacaine than with bupivacaine (mean +/- SD: 76 +/- 23 vs. 72 +/- 23, respectively; P = 0.013). Satisfaction for analgesia at delivery was higher for bupivacaine than for ropivacaine (mean +/- SD: 71 +/- 25 vs. 66 +/- 26, respectively; P = 0.037). CONCLUSIONS: There was no difference in the incidence of operative delivery or neonatal outcome among nulliparous patients who received low concentrations of bupivacaine or ropivacaine for labor analgesia. 相似文献
43.
Suzanne Gleason PhD Karen L. Furie MD Michael H. Lev MD Joan O''Donnell RN CNRN Pamela M. McMahon BS Molly T. Beinfeld MPH Elkan Halpern PhD Mark Mullins MD PhD Gordon Harris PhD Walter J. Koroshetz MD G. Scott Gazelle MD MPH PhD 《Academic radiology》2001,8(10):955-964
RATIONALE AND OBJECTIVES: Patients presenting with ischemic brain symptoms have widely variable outcomes dependent to some degree on the pathologic basis of their stroke syndrome. The purpose of this study was to determine the cost implications of the emergency use of a computed tomographic (CT) protocol comprising unenhanced CT, head and neck CT angiography, and whole-brain CT perfusion. MATERIALS AND METHODS: By using a retrospective patient database from a tertiary care facility and publicly available cost data, the authors derived the potential savings from the use of CT angiography. CT perfusion, or both at hospital arrival by means of a cost model. The cost of the CT angiography-CT perfusion protocol was determined from Medicare reimbursement rates and compared with that of traditional imaging protocols. Cost savings were estimated as a decrease in the length of stay for most stroke patients, whereas the most benign (lacunar) strokes were assumed to be managed in a non-acute setting. Misdiagnosis cost (erroneously not admitting a patient with nonlacunar stroke) was calculated as the cost of a severe complication. Sensitivity testing included varying the percentage of misdiagnosed patients and admitting patients with lacunar stroke. RESULTS: The nationwide net savings that would result from the adoption of the CT angiography-CT perfusion protocol are in the $1.2 billion range (-$154 million to $2.1 billion) when patients with lacunar strokes are treated nonacutely and $1.8 billion when those patients are admitted for acute care. CONCLUSION: The results demonstrate the potential effect of implementing a CT angiography-CT perfusion protocol. In particular, prompt CT angiography-CT perfusion imaging could have an effect on the cost of acute care in the treatment of stroke. 相似文献
44.
Mitterberger M Pinggera G Horninger W Strasser H Halpern E Pallwein L Gradl J Bartsch G Frauscher F 《European urology》2008,53(1):112-117
OBJECTIVES: This study assessed the effect of premedication with dutasteride, a dual 5alpha-reductase inhibitor, on prostatic blood flow prior to prostate biopsy and its impact on prostate cancer detection. METHODS: Thirty-six patients, aged 52-74 yr, with elevated prostate-specific antigen (PSA) levels (>or=1.25 ng/ml and free-to-total ratio of <18%) were treated with dutasteride 14 d prior to prostate biopsy. Contrast-enhanced colour Doppler (CECD) ultrasound was performed before and 7 and 14 d after dutasteride treatment. Contrast-enhanced targeted biopsies (相似文献
45.
Relative to other specialties, dermatologists have been slow to adopt advanced technologic diagnostic aids. Most skin disease can be diagnosed by simple visual inspection, and the skin is readily accessible for a diagnostic biopsy. Diagnostic aids, such as total body photography and dermoscopy, improve the clinician's ability to diagnose melanoma beyond unaided visual inspection, however, and are now considered mainstream methods for early detection. Emerging technologies such as in vivo reflectance confocal microscopy are currently being investigated to determine their utility for noninvasive diagnosis of melanoma. This review summarizes the currently available cutaneous imaging devices and new frontiers in noninvasive diagnosis of skin disease. We anticipate that multimodal systems that combine different imaging technologies will further improve our ability to detect, at the bedside, melanoma at an earlier stage. 相似文献
46.
Detection of clinically amelanotic malignant melanoma and assessment of its margins by in vivo confocal scanning laser microscopy. 总被引:9,自引:0,他引:9
K J Busam K Hester C Charles D L Sachs C R Antonescu S Gonzalez A C Halpern 《Archives of dermatology》2001,137(7):923-929
BACKGROUND: Near-infrared confocal scanning laser microscopy (CSLM) represents a novel imaging technique for in vivo microscopic analysis of skin lesions, including pigmented lesions. OBJECTIVES: To investigate the feasibility of detecting a clinically amelanotic malignant cutaneous melanoma using CSLM and to explore the use of this technique for assessing its margins. PATIENTS AND METHODS: Two lesions from 2 patients were imaged and analyzed using CSLM. Sites suspected to represent melanoma or benign skin on CSLM were marked as such; then, biopsy specimens were obtained for diagnosis using conventional histological analysis. Both lesions were stained for melanin pigment and analyzed immunohistochemically for the expression of melanosomal markers. In 1 case, a biopsy specimen was also examined with electron microscopy. RESULTS: The images obtained using CSLM allowed recognition of an abnormal intraepidermal melanocytic proliferation that was distinctly different from normal skin. Comparison of the sites examined using CSLM and subsequently using conventional histological methods revealed that CSLM correctly identified intraepidermal melanoma and benign skin. Fontana-Masson stains and immunohistochemical and ultrastructural studies showed that clinically amelanotic melanoma cells contained melanosomes and rare melanin granules. CONCLUSIONS: We demonstrated, for the first time, the detection of clinically amelanotic melanoma using CSLM. This technique may aid in the early detection of clinically barely visible or nonpigmented melanomas and may facilitate preoperative noninvasive assessment of their margins. 相似文献
47.
Carlos A. Charles Ashfaq A. Marghoob Klaus J. Busam Lesley Clark-Loeser Allan C. Halpern 《Skin research and technology》2002,8(4):282-287
Background/purpose: New techniques are being explored for improving diagnostic accuracy of pigmented skin lesions. Confocal scanning laser microscopy (CSLM) may represent such a novel technique. The purpose of this report was to demonstrate the potential application of CSLM as an aid in the diagnosis of a pigmented skin lesion that is clinically suspicious for melanoma.
Methods: An irregular pigmented lesion was examined clinically and dermoscopically. The lesion was imaged by CSLM and subsequently excised for histologic examination. Findings from CSLM were correlated with features observed on the dermoscopic and histologic examination.
Results: Confocal scanning laser microscopy (CSLM) allowed for the non-invasive visualization of the histologic features of superficial pigmented BCC, including buds and "islands" of tumor cells at the dermoepidermal junction and melanin-laden macrophages. Conventional histology confirmed the diagnosis of pigmented BCC.
Conclusion: Confocal scanning laser microscopy (CSLM) may serve as an aid in the non-invasive diagnosis of pigmented skin lesions clinically suspicious for melanoma. 相似文献
Methods: An irregular pigmented lesion was examined clinically and dermoscopically. The lesion was imaged by CSLM and subsequently excised for histologic examination. Findings from CSLM were correlated with features observed on the dermoscopic and histologic examination.
Results: Confocal scanning laser microscopy (CSLM) allowed for the non-invasive visualization of the histologic features of superficial pigmented BCC, including buds and "islands" of tumor cells at the dermoepidermal junction and melanin-laden macrophages. Conventional histology confirmed the diagnosis of pigmented BCC.
Conclusion: Confocal scanning laser microscopy (CSLM) may serve as an aid in the non-invasive diagnosis of pigmented skin lesions clinically suspicious for melanoma. 相似文献
48.
Edward T. Crosby Stephen H. Halpern Stephen H. Rolbin 《Journal canadien d'anesthésie》1989,36(6):701-704
The safety of epidural anaesthesia in patients with active, recurrent genital herpes simplex (HSV) infections is controversial. We reviewed the six-year experience of the use of epidural anaesthesia in this patient population in two institutions. Eighty-nine parturients with active genital HSV were administered epidural anaesthesia for Caesarean section. No patient suffered an adverse outcome related to either the anaesthetic or the virus. The theoretical risks of regional anaesthesia in the parturient with active herpes genitalis are reviewed. We conclude from available data that the risk of an adverse outcome is small and does not contraindicate the use of epidural anaesthesia in patients with recurrent infection. 相似文献
49.