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Michael A Choti

Publications and source records attributed to Michael A Choti.

36 records · Page 2Linked to original sources
PubMed2004

Percutaneous image-guided radiofrequency ablation of painful metastases involving bone: a multicenter study.

PURPOSE: Few options are available for pain relief in patients with bone metastases who fail standard treatments. We sought to determine the benefit of radiofrequency ablation (RFA) in providing pain relief for patients with refractory pain secondary to metastases involving bone. PATIENTS AND METHODS: Thirty-one US and 12 European patients with painful osteolytic metastases involving bone were treated with image-guided RFA using a multitip needle. Treated patients had > or = 4/10 pain and had either failed or were poor candidates for standard treatments such as radiation or opioid analgesics. Using the Brief Pain Inventory-Short Form, worst pain intensity was the primary end point, with a 2-unit drop considered clinically significant. RESULTS: Forty-three patients were treated (median follow-up, 16 weeks). Before RFA, the mean score for worst pain was 7.9 (range, 4/10 to 10/10). Four, 12, and 24 weeks following treatment, worst pain decreased to 4.5 (P <.0001), 3.0 (P <.0001), and 1.4 (P =.0005), respectively. Ninety-five percent (41 of 43 patients) experienced a decrease in pain that was considered clinically significant. Opioid usage significantly decreased at weeks 8 and 12. Adverse events were seen in 3 patients and included (1) a second-degree skin burn at the grounding pad site, (2) transient bowel and bladder incontinence following treatment of a metastasis involving the sacrum, and (3) a fracture of the acetabulum following RFA of an acetabular lesion. CONCLUSION: RFA of painful osteolytic metastases provides significant pain relief for cancer patients who have failed standard treatments.

Adult↗
PubMed2004

Palliative therapy for pancreatic/biliary cancer.

Palliative treatment for unresectable pancreatic and biliary cancer is most typically directed at symptoms of local invasion, including obstructive jaundice, duodenal obstruction, and cancer-related pain. Surgical and nonsurgical therapeutic options should be considered depending on the individual situation. As with all treatment planning, palliative therapy should be planned using a multidisciplinary approach, including input from the surgeon, gastroenterologist,radiologist, and medical and radiation oncologist.

Biliary Tract Neoplasms↗
PubMed2003

Transcatheter arterial chemoembolization of liver tumors: effects of embolization protocol on injectable volume of chemotherapy and subsequent arterial patency.

The purpose of this study was to determine whether transcatheter arterial chemoembolization (TACE) protocol affects the total volume of chemotherapy injected into the liver as well as subsequent arterial patency. A total of 160 patients with primary or secondary liver cancer were treated with 3 different chemoembolization protocols at a single institution. Data were analyzed retrospectively. Group 1 (n = 36) consisted of slurry of chemotherapy, oil and polyvinyl alcohol particles (PVA), group 2 (n = 91), chemotherapy and oil followed by PVA, and group 3 (n = 33), chemotherapy and oil followed by Gelfoam pledgets. The total volume of chemotherapy injected into the liver was recorded. Arterial patency was determined during subsequent chemoembolizations. The mean percentage of total intended chemotherapy dose administered was 54.6% for group 1, 75.3% for group 2, and 80.6% for group 3. Arterial patency at follow-up angiography was 56% for group 1, 74% for group 2, and 81% for group 3. The slurry protocol (group 1) significantly reduced arterial patency and injectable volume of chemotherapy during TACE.

Angiography, Digital Subtraction↗
PubMed2003

Chemoembolization of hepatocellular carcinoma: results of a metaanalysis.

Transcatheter arterial chemoembolization is considered the mainstay of therapy for unresectable hepatocellular carcinoma. The purpose of this study was to assess the impact of such treatment on survival by performing a metaanalysis of all available randomized clinical trials comparing this form of therapy to supportive care. A MEDLARS search was conducted covering the years 1970 to 2002. Data analysis was performed according to methods described by Peto. The primary outcome of interest was the proportion of patients surviving 3 and 6 months after treatment. All analyses were performed on an intent-to-treat basis. A literature search yielded 1,100 citations, from which four met protocol-specified inclusion criteria. All studies contained an experimental and control arm totalling 268 patients. The odds ratio for 3- and 6-month survival were 1.31 (95% CI: 0.66-2.58) and 0.91 (95% CI: 0.49-1.68), which was not statistically significant. These data fail to show a survival advantage associated with therapeutic embolization versus supportive care alone in patients with unresectable hepatocellular carcinoma. Existing survival data from randomized controlled trials are of poor quality, and the paucity of patients in these trials eliminates the possibility of drawing meaningful conclusions regarding the effect of chemoembolization on patient survival from these studies.

Antineoplastic Agents↗
PubMed2003

Results of pancreaticoduodenectomy for lymphoplasmacytic sclerosing pancreatitis.

OBJECTIVE: To compare the presentation and short-term results of pancreaticoduodenectomy for lymphoplasmacytic sclerosing pancreatitis (LPSP) and pancreatic adenocarcinoma (PA) and to provide long-term follow-up on patients undergoing resection for LPSP. SUMMARY BACKGROUND DATA: LPSP is a rare form of chronic pancreatitis characterized by a mixed inflammatory infiltrate centered around pancreatic ducts and ductules, combined with obliterative phlebitis. Its presentation may mimic that of PA. METHODS: Among 1,648 patients undergoing pancreaticoduodenectomy at the authors' institution from January 1992 to May 2002, 37 with LPSP were identified. The demographics, clinical features, and short- and long-term outcomes of these patients were analyzed. Where applicable, comparisons were made to a consecutive group of 45 patients who underwent pancreaticoduodenectomy for PA from July 2001 to December 2001. RESULTS: Twenty-four percent (9/37) of the LPSP patients and none of the PA patients had a history of either atopic or autoimmune disease. The LPSP patients had a similar clinical presentation to the PA patients, but the LPSP patients were less likely to have a discrete pancreatic mass on CT and more likely to have CT findings suggesting a diffusely enlarged pancreas. The LPSP patients were also less likely to have a discrete pancreatic mass at operation, more likely to have a diffusely firm or hard gland, and more likely to have a difficult portal vein/superior mesenteric vein dissection when compared to the PA patients. Transfusion requirement, operative time, postoperative length of stay, and overall complication rate were similar between groups; however, the LPSP patients had a greater operative blood loss. The median length of follow-up for LPSP patients was 33 months. No patients had recurrent jaundice. One patient with LPSP had clinically evident recurrent pancreatitis. Among LPSP patients available for current telephone interview, 68% subjectively rated their quality of life as better, 18% reported no change, and 14% reported diminished quality of life compared to before surgery. CONCLUSION: LPSP mimics PA in clinical presentation, though CT findings of a diffusely enlarged pancreas without a discrete mass may suggest a diagnosis of LPSP. Nevertheless, differentiation from pancreatic neoplasia remains difficult. Patients undergoing pancreaticoduodenectomy for LPSP have durable relief of symptoms and a subjectively improved quality of life.

Adenocarcinoma↗
PubMed2003

Surgically staged focal liver lesions: accuracy and reproducibility of dual-phase helical CT for detection and characterization.

PURPOSE: To assess the accuracy and reproducibility of dual-phase helical computed tomography (CT) in enabling preoperative detection and characterization of surgically staged focal liver lesions. MATERIALS AND METHODS: Surgically and histopathologically proven liver lesions were evaluated by three experienced CT readers. These lesions were present in 77 patients who underwent dual-phase helical CT. Images were interpreted separately by the three blinded reviewers. Each lesion was graded on a nine-point scale of confidence, with 1 being definitely benign, 9 being definitely malignant, and 5 being indeterminate. The chi2 test was used to determine if the distribution of lesion classifications was different between readers. RESULTS: There was a total of 237 lesions: 73 were benign and 164 were malignant. Sensitivity for lesion detection was 69%, 70%, and 71% for the three reviewers, respectively. Specificity was 91%, 86%, and 90%, and the area under the curve for the alternative-free response receiver operating characteristic curve was 0.84, 0.83, and 0.85, respectively. The difference in the distributions of lesion classification between the three reviewers was not statistically significant (P =.67) as determined by chi2 analysis. CONCLUSION: Dual-phase CT has sensitivity of 69%-71% and high specificity (86%-91%) in enabling the detection and characterization of focal liver lesions. Interpretation is highly reproducible, as there is minimal variation between experienced reviewers.

Female↗
PubMed2002

Counting alleles to predict recurrence of early-stage colorectal cancers.

BACKGROUND: Chromosome imbalances occur in many cancers and represent important biological properties of tumours. However, measurements of such imbalances are difficult. We used a new, quantitative approach to investigate the prognostic value of chromosome imbalances in early-stage colorectal cancers. METHODS: We studied 180 patients with no evidence of lymph-node or distant metastases at the time of surgery. DNA from paraffin-embedded tumours was tested for imbalances of chromosome 8p and 18q by digital SNP (single-nucleotide polymorphism)-a technique in which each allele in a sample is directly counted. Surviving patients had median follow-up of 68 months, and disease recurrence was used as the clinical endpoint. FINDINGS: Tumours were divided into three groups: "L" tumours (n=93) had allelic imbalances of chromosomes 8p and 18q, "L/R" tumours (n=60) had allelic imbalances of either chromosome 8p or 18q but not both, and "R" tumours (n=27) retained allelic balance for both chromosomes. 5-year disease-free survival was 100% (95% CI 80-100) for patients with R tumours, 74% (61-87) for patients with L/R tumours, and 58% (47-69) for those with L tumours. These differences were significant (p<0.0001) and were independent of other variables--eg, Duke's stage A tumours of class L were much more likely to recur than Duke's stage B tumours of class R (p=0.002). INTERPRETATION: In patients without metastasis, allelic imbalance is a better predictor of prognosis than histopathological stage.

Aged↗
PubMed2002

Percutaneous gadolinium injection under MR guidance to mark target for CT-guided radiofrequency ablation.

Selection of the appropriate imaging tool depends on a number of factors that reflect the patient, the procedure, and the physician. Multiple imaging techniques are often required to perform elements of a whole procedure. A patient with an allergy to iodinated contrast material and a 3.0-cm hepatic metastasis that was invisible on computed tomography (CT) was treated with CT-guided radiofrequency ablation by first injecting gadolinium under magnetic resonance guidance to mark the location of the lesion. Gadolinium's high atomic number makes it a viable contrast agent for attenuating x rays under fluoroscopic or CT guidance.

Aged↗
PubMed2002

Surgical management of hepatocellular carcinoma: resection and ablation.

In this article, the author reviews the recent advances in the surgical management of hepatocellular carcinoma (HCC). Partial hepatic resection or, in some instances, liver transplantation provides the best chance for cure. Risk of perioperative mortality after partial hepatectomy is less than 5% in most experienced centers. Careful preoperative assessment of hepatic function is important to reduce the risk of postoperative liver failure after liver resection. Long-term outcomes after resection are comparable to those with liver transplantation, with reported 5-year survival rates of 25%-50%. Although limited controlled comparative studies exist, surgical and nonsurgical local ablative therapies, including ethanol and radiofrequency ablation, may result in survival benefit.

Carcinoma, Hepatocellular↗
PubMed2002

Influence of a new prophylactic antibiotic therapy on the incidence of liver abscesses after chemoembolization treatment of liver tumors.

Intrahepatic abscess is a complication of transcatheter arterial chemoembolization (TACE) treatment in patients who have a history of biliary reconstructive surgery. This study followed eight patients who underwent chemoembolization after biliary surgery. These patients were divided into two groups. Patients in group one (n = 4) were administered intravenous cephalexin for prophylaxis. Patients in group two (n = 4) were administered bowel preparation and tazobactam/piperacillin. All patients in group one developed hepatic abscesses, which were treated with percutaneous catheter drainage and antibiotics. None of the patients in group two developed abscesses. Aggressive antibiotic prophylaxis with bowel preparation may provide protection against intrahepatic abscesses after chemoembolization in patients who have a history of biliary reconstructive surgery.

Adenocarcinoma↗
PubMed2002

Trends in long-term survival following liver resection for hepatic colorectal metastases.

OBJECTIVE: To examine trends in outcomes of patients undergoing resection at a single tertiary care referral center over a 16-year period. SUMMARY BACKGROUND DATA: Hepatic resection is considered the treatment of choice in selected patients with colorectal metastasis confined to the liver. Although a variety of retrospective studies have demonstrated improvements in short-term outcomes in recent years, changes in long-term survival over time are less well-established. METHODS: Data from 226 consecutive patients undergoing potentially curative liver resection for colorectal metastases between 1984 and 1999 were analyzed. Actuarial survival rates related to prognostic determinants were analyzed using the log-rank test. RESULTS: The median survival for the entire cohort was 46 months, with 5- and 10-year survival rates of 40% and 26% respectively. Ninety-three patients operated on between 1984 and 1992 were found to have an overall survival of 31% at 5 years, compared to 58% for the 133 patients operated on during the more recent period (1993-1999). Both overall and disease-free survival were significantly better in the recent time period compared with the earlier period on both univariate and multivariate analyses. Other independent factors associated with improved survival included number of metastatic tumors < or = 3, negative resection margin, and CEA < 100. Comparisons were made between time periods for a variety of patient, tumor and treatment-related factors. Among all parameters studied, only resection type (anatomical versus nonanatomical), use of intraoperative ultrasonography, and perioperative chemotherapy administration differed between the early and recent time periods. CONCLUSIONS: Long-term survival following liver resection for colorectal metastases has improved significantly in recent years at our institution. Although the reasons for this survival trend are not clear, contributing factors may include the use of newer preoperative and intraoperative imaging, increased use of chemotherapy, and salvage surgical therapy.

Adult↗
PubMed2002

Liver lesions: manganese-enhanced MR and dual-phase helical CT for preoperative detection and characterization comparison with receiver operating characteristic analysis.

PURPOSE: The purpose of this study was to compare, by means of receiver operating characteristic (ROC) analysis, dual-phase helical computed tomography (CT) and manganese-enhanced magnetic resonance (MR) imaging in the detection and characterization of hepatic lesions in patients prior to surgery. MATERIALS AND METHODS: Twenty-five patients known to have or suspected of having hepatic lesions who were eligible for surgery underwent dual-phase (ie, arterial and portal phase) helical CT and phased-array MR imaging (ie, unenhanced fast spin-echo T2-weighted imaging and gradient-echo T1-weighted imaging performed before and after administration of mangafodipir trisodium). All images were reviewed independently by three off-site blinded reviewers who separately reviewed the CT scans and MR images. The standard of reference was findings at surgery, intraoperative ultrasonography (US), and histopathologic examination. ROC curves were established to analyze the results for each reader and modality. RESULTS: Ninety-four lesions (77 malignant and 17 benign) were revealed at surgery, intraoperative US, and/or histopathologic examination. The overall rate of lesion detection for the three readers at CT was 81.9% +/- 7.8, 90.4% +/- 5.9, and 76.6% +/- 8.6. At MR imaging, the detection rates were 72.3% +/- 9.0, 71.3% +/- 9.1, and 69.1% +/- 9.3 (P =.001 for the difference between MR and CT). The average rate of false-positive diagnoses in patients was 14.1% at CT and 6.4% at MR imaging (P =.06 for the difference between MR and CT). The mean areas under the alternative-free-response ROC curves were 0.74 for MR and 0.72 for CT (P =.751, not significant). CONCLUSION: In detection and characterization of liver lesions, manganese-enhanced MR imaging and dual-phase helical CT were not statistically different.

Adult↗
PubMedDate not supplied

Survival after gastric adenocarcinoma resection: eighteen-year experience at a single institution.

Gastric adenocarcinoma is the second leading cause of cancer death worldwide. In Western series, survival rates vary widely and are generally lower than those reported from Eastern series. We performed a retrospective analysis of cases operated on at the Johns Hopkins Hospital over the past 18 years and collected data on demographics, tumor characteristics, pathologic stage, treatment methods, complications, survival time, and other relevant factors. Survival according to stage of disease, Lauren tumor type, tumor location, time period, and administration of adjuvant therapy was analyzed, and results were compared with those of other Western series. During this period, 436 patients with gastric adenocarcinoma underwent resection. We have shown a statistically significant association between survival and margin status, stage of disease, and Lauren tumor type. Overall 5-year survival was 26%, and 5-year survival after R0 resection was 33%. No significant difference was detected between survival and tumor location, time period of treatment, or administration of adjuvant therapy. Analysis of various Western series reveals major differences between the cohorts under study, such as stage of disease, extent of resection, tumor type, and tumor location. Many of the reported differences among Western series may be due to cohort differences, such as stage of disease, extent of resection, tumor type, and tumor location.

Adenocarcinoma↗