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Dive into the research topics where Marcovalerio Melis is active.

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Featured researches published by Marcovalerio Melis.


Annals of Surgical Oncology | 2008

PET/CT Fusion Scan Enhances CT Staging in Patients with Pancreatic Neoplasms

Jeffrey M. Farma; Alfredo A. Santillan; Marcovalerio Melis; Janet Walters; Daly Belinc; Dung-Tsa Chen; Edward A. Eikman; Mokenge P. Malafa

BackgroundThe role of fusion positron emission tomography/computed tomography scans (PET/CT) in staging of patients with pancreatic neoplasms (PN) is poorly defined. PET/CT may serve as an adjunct to standard imaging by increasing occult metastases detection. The purpose of this study was to assess the additional value, in relation to computed tomography (CT), of PET/CT imaging for patients with PN.MethodsEighty-two patients with potentially resectable PN underwent staging with PET/CT and CT of the chest and abdomen. Sensitivity of diagnosing pancreatic cancer by PET/CT avidity was evaluated. The sensitivity of detecting metastases was compared between PET/CT, standard CT, and the combination of PET/CT and CT. The impact of PET/CT on patient management was estimated by calculating the percentage of patients whose treatment plan was altered due to PET/CT.ResultsThe sensitivity and specificity of PET/CT in diagnosing pancreatic cancer were 89% and 88%, respectively. Sensitivity of detecting metastatic disease for PET/CT alone, standard CT alone, and the combination of PET/CT and CT were 61%, 57%, and 87%, respectively. Findings on PET/CT influenced the clinical management in seven patients (11%), two with a supraclavicular lymph node (LN), two occult liver lesions, two peritoneal implants, and one peri-esophageal LN.ConclusionThis study evaluated PET/CT in the initial work-up of patients with PN. PET/CT increased sensitivity (87%) for detection of metastatic disease when combined with standard CT. In invasive cancer, PET/CT changed the management in 11% of our patients. PET/CT should be considered in the initial work-up of patients with potentially resectable pancreatic lesions.


Surgical Endoscopy and Other Interventional Techniques | 2005

Metaanalysis of trials comparing laparoscopic and open surgery for Crohn’s disease

Alan S. Rosman; Marcovalerio Melis; Alessandro Fichera

Background:Several studies in the literature have suggested that laparoscopic surgery for Crohn’s disease is associated with faster postoperative recovery and a morbidity and recurrence rate similar to that for open surgery. Most of these studies have been limited by a small sample size and a short follow-up period.Methods:To clarify whether open or laparoscopic resection results in a better outcome, a metaanalysis of studies was performed comparing the two procedures for Crohn’s disease. Pooled effects were estimated using a random-effects model.Results:Laparoscopic surgery required more operative time than open surgery (26.8 min; 95% confidence interval [CI], 6.4–47.2 min), but resulted in a shorter duration of ileus and a decreased hospital stay (−2.62 days; 95% CI, −3.62 to −1.62). Laparoscopic surgery also was associated with a decreased rate for postoperative bowel obstruction and surgical recurrences.Conclusions:Laparoscopic surgery for Crohn’s disease is feasible, safe, and associated with shorter duration of ileus and a shorter hospital stay.


Surgical Endoscopy and Other Interventional Techniques | 2011

Metaanalysis of trials comparing minimally invasive and open distal pancreatectomies

Giuseppe Nigri; Alan S. Rosman; Niccolò Petrucciani; Alessandro Fancellu; Michele Pisano; Luigi Zorcolo; Giovanni Ramacciato; Marcovalerio Melis

BackgroundThe current literature suggests that minimally invasive distal pancreatectomy (MIDP) is associated with faster recovery and less morbidity than open surgery. However, most studies have been limited by a small sample size and a single-institution design. To overcome this problem, the first metaanalysis of studies comparing MIDP and open distal pancreatectomy (ODP) has been performed.MethodsA systematic literature review was conducted to identify studies comparing MIDP and ODP. Perioperative outcomes (e.g., morbidity and mortality, pancreatic fistula rates, blood loss) constituted the study end points. Metaanalyses were performed using a random-effects model.ResultsFor the metaanalysis, 10 studies including 349 patients undergoing MIDP and 380 patients undergoing ODP were considered suitable. The patients in the two groups were similar with respect to age, body mass index (BMI), American Society of Anesthesiology (ASA) classification, and indication for surgery. The rate of conversion from full laparoscopy to hand-assisted procedure was 37%, and that from minimally invasive to open procedure was 11%. Patients undergoing MIDP had less blood loss, a shorter time to oral intake, and a shorter postoperative hospital stay. The mortality and reoperative rates did not differ between MIDP and ODP. The MIDP approach had fewer overall complications [odds ratio (OR), 0.49; 95% confidence interval (CI), 0.27–0.89], major complications (OR, 0.57; 95% CI, 0.34–0.96), surgical-site infections (OR, 0.32; 95% CI, 0.19–0.53), and pancreatic fistulas (OR, 0.68; 95% CI, 0.47–0.98).ConclusionsThe MIDP procedure is feasible, safe, and associated with less blood loss and overall complications, shorter time to oral intake, and shorter postoperative hospital stay. Furthermore, the minimally invasive approach reduces the rate of pancreatic leaks and surgical-site infections after ODP.


Annals of Surgery | 2000

Side-to-side isoperistaltic strictureplasty in extensive Crohn's disease : a prospective longitudinal study

Fabrizio Michelassi; Roger D. Hurst; Marcovalerio Melis; Michele Rubin; Russell D. Cohen; Arunas Gasparitis; Stephen B. Hanauer; John Hart

ObjectiveTo report on the results of a prospective longitudinal study of a new bowel-sparing procedure (side-to-side isoperistaltic strictureplasty [SSIS]) in patients with extensive Crohn’s disease. MethodsBetween January 1992 and April 1999, the authors operated on 469 consecutive patients for Crohn’s disease of the small bowel. Seventy-one patients (15.1%) underwent at least one strictureplasty; of these, 21 (4.5%; 12 men, 9 women; mean age 39) underwent an SSIS. The long-term changes occurring in the SSIS were studied radiographically, endoscopically, and histopathologically. ResultsThe indication for surgical intervention was symptomatic partial intestinal obstruction in each of the 21 patients. Fourteen SSISs were constructed in the jejunum, four in the ileum, and three with ileum overlapping colon. The average length of the SSIS was 24 cm. Performance of an SSIS instead of a resection resulted in preservation of an average of 17% of small bowel length. One patient suffered a postoperative gastrointestinal hemorrhage. All patients were discharged on oral feedings after a mean of 8 days. In all cases, SSIS resulted in resolution of the preoperative symptoms. With follow-up extending to 7.5 years in 20 patients (one patient died of unrelated causes), radiographic, endoscopic, and histopathologic examination of the SSIS suggests regression of previously active Crohn’s disease. ConclusionsSSIS is a safe and effective procedure in patients with extensive Crohn’s disease. The authors’ results provide radiographic, endoscopic, and histopathologic evidence that active Crohn’s disease regresses at the site of the SSIS.


Journal of Surgical Oncology | 2008

Multimodality management of desmoid tumors: how important is a negative surgical margin?

Marcovalerio Melis; Jonathan S. Zager; Vernon K. Sondak

Desmoid tumors are rare, locally invasive mesenchymal tumors without metastatic potential. Their clinical behavior is heterogeneous and characteristically unpredictable; outcomes are influenced by anatomic location, proximity to vital organs, association with familial adenomatous polyposis. Surgery is the main treatment modality, but the significance of positive resection margins remains controversial since they may not increase the risk of recurrence: in this setting re‐resection, adjuvant radiation or close clinical follow‐up could all be appropriate options. We reviewed the current evidence for multimodality therapy of desmoids, with a focus on the importance of resection margins, and present our own algorithm for treatment. J. Surg. Oncol. 2008;98:594–602.


Journal of Surgical Research | 2011

Meta-Analysis of Trials Comparing Minimally-Invasive and Open Liver Resections for Hepatocellular Carcinoma

Alessandro Fancellu; Alan S. Rosman; Valeria Sanna; Giuseppe Nigri; Luigi Zorcolo; Michele Pisano; Marcovalerio Melis

BACKGROUND Recent literature suggests that minimally-invasive hepatectomy (MIH) for hepatocellular carcinoma (HCC) is associated with better perioperative results and similar oncologic outcomes compared to open hepatectomy (OH). However, previous reports have been limited by small sample size and single-institution design. METHODS To overcome these limitations, we performed a meta-analysis of studies comparing MIH and OH in patients with HCC using a random-effects model. RESULTS Nine eligible studies were identified that included 227 patients undergoing MIH and 363 undergoing OH. Patients were similar respect to age, gender, rates of cirrhosis, hepatitis C infection, tumour size, and American Society of Anesthesiology classification. The MIH group had lower rates of hepatitis B infection. There were no differences in type of resection (anatomic or non-anatomic), use of Pringles maneuver, and operative time. Patients undergoing MIH had less blood loss [difference -217 mL; 95% confidence interval (CI), -314 to -121], lower rates of transfusion [odds ratio (OR), 0.38; 95% CI, 0.24 to 0.59], shorter postoperative stay (difference -5 days; 95% CI, -7.84 to -2.25), lower rates of positive margins (OR, 0.30; 95% CI, 0.12 to 0.69) and perioperative complications (OR, 0.45; 95% CI, 0.31 to 0.66). Survival outcomes were similar in the two groups. CONCLUSIONS Although patient selection might have influenced some of the observed outcomes, MIH was associated with decreased blood loss, transfusions, rates of positive resection margins, overall and specific morbidity, and hospital stay. Survival outcomes did not differ between MIH and OH, although further studies are needed to evaluate the impact of MIH on long-term results.


Surgery | 2013

Meta-analysis of trials comparing laparoscopic transperitoneal and retroperitoneal adrenalectomy

Giuseppe Nigri; Alan S. Rosman; Niccolò Petrucciani; Alessandro Fancellu; Michele Pisano; Luigi Zorcolo; Giovanni Ramacciato; Marcovalerio Melis

BACKGROUND Laparoscopic adrenalectomies are being performed increasingly, either with transperitoneal or retroperitoneal approaches. Studies comparing the 2 approaches have not shown the superiority of either technique, but these studies are limited by small sample sizes and single-institution designs. To overcome these limitations, we performed a meta-analysis of studies comparing lateral transperitoneal adrenalectomy and retroperitoneal adrenalectomy. METHODS A systematic review of studies comparing lateral transperitoneal adrenalectomy and retroperitoneal adrenalectomy was conducted. Study endpoints included perioperative outcomes and measures of postoperative recovery. Meta-analysis was performed using a random effects model, pooling variables evaluated by more than 3 studies. RESULTS Twenty-one studies comparing a total of 1,205 lateral transperitoneal adrenalectomies and 688 retroperitoneal adrenalectomies were suitable for meta-analysis. Patients in the 2 groups were similar in term of age, sex, body mass index, lesion size and location, and rates of malignancy. There were no statistically significant differences between lateral transperitoneal adrenalectomy and retroperitoneal adrenalectomy in terms of operative time, blood loss, hospital stay, time to oral intake, overall and major morbidity, and mortality. CONCLUSION Both lateral transperitoneal adrenalectomy and retroperitoneal adrenalectomy are associated with very low rates of perioperative complications. According to our meta-analysis, clinical outcomes after either technique are similar. For most adrenal lesions requiring operation, minimally invasive adrenalectomy can be performed safely and effectively with either transperitoneal or the retroperitoneal approach. Additional studies may be needed to analyze if any difference in long-term results exist.


Hpb | 2012

Spontaneous regression of hepatocellular carcinoma is most often associated with tumour hypoxia or a systemic inflammatory response

Jonathan I. Huz; Marcovalerio Melis; Umut Sarpel

BACKGROUND Spontaneous regression of hepatocellular carcinoma (HCC) is well documented, although the aetiology of this phenomenon remains unknown. METHODS A review of the English literature was performed for reports of spontaneous regression of HCC. Reports were classified by mechanism based on the available information. RESULTS Spontaneous regression of HCC has been identified in 75 patients. The most common mechanisms of regression identified were tumour hypoxia (n= 21, 28.0%), a systemic inflammatory response (n= 25, 33.3%) and unknown (n= 29, 38.7%). In patients where tumour hypoxia was described as the aetiology, mechanisms included spontaneous hepatic artery thrombosis and sustained systemic hypotension. In patients where a systemic inflammatory response was the aetiology, mechanisms included cholangitis, trauma and elevated cytokine levels. DISCUSSION Spontaneous regression of HCC is most commonly associated with tumour hypoxia or a systemic inflammatory response. Determining the aetiology of spontaneous regression may identify potential therapeutic pathways. Tumour hypoxia is already the basis of treatment modalities such as hepatic artery embolization and the anti-angiogenic agent sorafenib. However, treatment modalities for HCC do not currently include immune-directed therapies; this may prove to be a worthy target for future research.


Hpb | 2012

The safety of a pancreaticoduodenectomy in patients older than 80 years: risk vs. benefits

Marcovalerio Melis; F. Marcon; Antonio Masi; Antonio Pinna; Umut Sarpel; George Miller; Harvey G. Moore; Steven P. Cohen; Russell S. Berman; H. Leon Pachter; Elliot Newman

BACKGROUND A pancreaticoduodenectomy (PD) offers the only chance of a cure for pancreatic cancer and can be performed with low mortality and morbidity. However, little is known about outcomes of a PD in octogenarians. METHODS Differences in two groups of patients (Group Y, <80 and Group O, ≥80 year-old) who underwent a PD for pancreatic adenocarcinoma were analysed. Study end-points were length of post-operative stay, overall morbidity, 30-day mortality and overall survival. RESULTS There were 175 patients in Group Y (mean age 64 years) and 25 patients in Group O (mean age 83 years). Octogenarians had worse Eastern Cooperative Oncology Group (ECOG) Performance Status (PS ≥1: 90% vs. 51%) and American Society of Anesthesiology (ASA) score (>2: 71% vs. 47%). The two groups were similar in underlying co-morbidities, operative time, rates of portal vein resection, intra-operative complications, blood loss, pathological stage and status of resection margins. Octogenarians had a longer post-operative stay (20 vs. 14 days) and higher overall morbidity (68% vs. 44%). There was a single death in each group. At a median follow-up of 13 months median survival appeared similar in the two groups (17 vs. 13 months). CONCLUSIONS As 30-day mortality and survival are similar to those observed in younger patients, a PD can be offered to carefully selected octogenarians.


Journal of The American College of Surgeons | 2008

Are patients with esophageal cancer who become PET negative after neoadjuvant chemoradiation free of cancer

James M. McLoughlin; Marcovalerio Melis; Erin M. Siegel; E. Michelle Dean; Jill Weber; Jeannie Chern; Melanie Elliott; Scott T. Kelley; Richard C. Karl

BACKGROUND Esophageal cancer continues to increase in incidence. Many patients are presenting with stage II or greater disease and proceeding to neoadjuvant chemoradiation therapy before resection. Approximately 30% of patients will achieve a complete response and might not benefit from proceeding to resection. This study will examine the ability of PET to predict patients with a complete pathologic response. STUDY DESIGN A query of our IRB-approved esophageal database revealed 81 patients who underwent a pre- and postchemoradiation PET scan and then proceeded to esophageal resection. Statistical analysis was performed to determine the ability of PET to predict a complete pathologic response. RESULTS When comparing posttherapy PET with final pathology, it was determined that PET could not consistently differentiate a complete pathologic response from patients who still had persistent disease. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 61.8%, 43.8%, 70%, 35%, and 56%, respectively, for patients with a complete PET response after neoadjuvant therapy. CONCLUSIONS A complete PET response after neoadjuvant chemoradiation is not substantially predictive of a complete pathologic response. Patients should still be referred for resection unless distant metastases are identified.

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Alan S. Rosman

Icahn School of Medicine at Mount Sinai

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Richard C. Karl

University of South Florida

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Jill Weber

University of South Florida

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