Eren Berber

Predictors of Survival After Radiofrequency Thermal Ablation of Colorectal Cancer Metastases to the Liver: A Prospective Study

PURPOSE The aim of this study was to determine the predictors of survival at the time of radiofrequency thermal ablation (RFA) in patients with colorectal liver metastasis. PATIENTS AND METHODS One hundred thirty-five patients with colorectal liver metastases who were not candidates for resection underwent laparoscopic RFA. RESULTS The median Kaplan-Meier survival for all patients was 28.9 months after RFA treatment. Patients with a carcinoembryonic antigen (CEA) less than 200 ng/mL had improved survival compared with those with a CEA more than 200 (34 v 16 months; P = .01). Patients with the dominant lesion less than 3 cm in diameter had a median survival of 38 v 34 months for lesions 3 to 5 cm, and 21 months for lesions greater than 5 cm (P = .03). Survival approached significance for patients with one to three tumors versus more than three tumors (29 v 22 months; P = .09). The presence of extrahepatic disease did not affect survival. Only the largest liver tumor size more than 5 cm was found to be a significant predictor of mortality by Cox proportional hazards model, with a 2.5-fold increased risk of death versus the largest liver tumor size less than 3 cm (P = .05). CONCLUSION This study determines which patients do best after RFA. Historical survival with chemotherapy alone is 11 to 14 months, suggesting RFA has a positive impact on overall survival. Limited amounts of extrahepatic disease do not appear to affect survival adversely. RFA is a useful adjunct to chemotherapy in those patients with liver-predominant disease.

Laparoscopic radiofrequency ablation of neuroendocrine liver metastases.

We previously reported on the safety and efficacy of laparoscopic radiofrequency thermal ablation (RFA) for treating hepatic neuroendocrine metastases. The aim of this study is to report our 5-year RFA experience in the treatment of these challenging group of patients. Of the 222 patients with 803 liver primary and secondary tumors undergoing laparoscopic RFA between January 1996 and August 2001, a total of 34 patients with 234 tumors had neuroendocrine liver metastases. There were 25 men and 9 women with a mean ± SEM age of 52 ± 2 years who underwent 42 ablations. Primary tumor types included carcinoid tumor in 18 patients, medullary thyroid cancer in 7, secreting islet cell tumor in 5, and nonsecreting islet cell tumor in 4. There was no mortality, and the morbidity was 5%. The mean hospital stay was 1.1 days. Symptoms were ameliorated in 95%, with significant or complete symptom control in 80% of the patients for a mean of 10+ months (range 6–24 months). All patients were followed for a mean ± SEM of 1.6 ± 0.2 years (range 1.0–5.4 years). During this period new liver lesions developed in 28% of patients, new extrahepatic disease in 25%, and local liver recurrence in 13%; existing liver lesions progressed in 13%. Overall 41% of patients showed no progression of their cancer. Nine patients (27%) died. Mean ± SEM survivals after diagnosis of primary disease, detection of liver metastases, and performance of RFA were 5.5 ± 0.8 years, 3.0 ± 0.3 years, and 1.6 ± 0.2 years, respectively. Sixty-five percent of the patients demonstrated a partial or significant decrease in their tumor markers during follow-up. In conclusion, RFA provides excellent local tumor control with overnight hospitalization and low morbidity in the treatment of liver metastases from neuroendocrine tumors. It is a useful modality in the management of these challenging group of patients.

Survival after radiofrequency ablation of colorectal liver metastases: 10-year experience.

Objective:To assess factors affecting long-term survival of patients undergoing radiofrequency ablation (RFA) of colorectal hepatic metastases, with attention to evolving chemotherapy regimens. Methods:Prospective evaluation of 235 patients with colorectal metastases who were not candidates for resection and/or failed chemotherapy underwent laparoscopic RFA. Preoperative risk factors for survival and pre- and postoperative chemotherapy exposure were analyzed. Results:Two hundred and thirty-four patients underwent 292 RFA sessions from 1997 to 2006, an average of 8 months after initiation of chemotherapy. Twenty-three percent had extrahepatic disease preoperatively. Patients averaged 2.8 lesions, with a dominant diameter of 3.9 cm. Kaplan-Meier actuarial survival was 24 months, with actual 3 and 5 years survival of 20.2% and 18.4%, respectively. Median survival was improved for patients with ≤3 versus >3 lesions (27 vs. 17 months, P = 0.0018); dominant size <3 versus >3 cm (28 vs. 20 months, P = 0.07); chorioembryonic antigen <200 versus >200 ng/mL (26 vs. 16 months, P = 0.003). Presence of extrahepatic disease (P = 0.34) or type of pre/postoperative chemotherapy (5-FU-leucovorin vs. FOLFOX/FOLFIRI vs. bevacizumab) (P = 0.11) did not alter median survival. Conclusions:To our knowledge, this is both the largest and longest follow-up of RFA for colorectal metastases. The number and dominant size of metastases, and preoperative chorioembryonic antigen value are strong predictors of survival. Despite classic teaching, extrahepatic disease did not adversely affect survival. In this group of patients who failed chemotherapy, newer treatment regimens (pre- or postoperatively) had no survival benefit. The actual 5-year survival of 18.4% in these patients versus near zero survival for chemotherapy alone argues for a survival benefit of RFA.

Predicting the success of limited exploration for primary hyperparathyroidism using ultrasound, sestamibi, and intraoperative parathyroid hormone: analysis of 1158 cases.

Objective:The aim of this study was to determine the success of limited neck exploration (LE) for primary hyperparathyroidism (1° HPT). Methods:Between 1999 and 2007, 1407 patients with hyperparathyroidism underwent bilateral neck exploration (BE). Of these, 1158 patients with first-time sporadic 1° HPT were analyzed prospectively. Based on surgeon-performed ultrasound (US) and sestamibi scan (MIBI), LE was initially performed. Regardless of results, BE followed to identify the presence of additional parathyroid pathology. Results:Of 1158 patients, 242 (21%) were found to require concomitant thyroid surgery thus excluding LE. Of the remaining 916 patients, a single abnormal gland was identified on MIBI in 682 (74%), US in 731 (80%), and concordance of both in 588 (64%). Unsuspected multiglandular disease (MGD) was identified at BE in 22%, 22%, and 20% of patients, respectively. Adding intraoperative parathyroid hormone sampling (IOPTH) further reduced the rate of unsuspected MGD to 16%, 17%, and 16%. Overall, IOPTH correctly predicted MGD in only 22%. Neither concomitant nonsurgical thyroid disease nor more stringent selection criteria (preop Ca>11 mg/dL and PTH>120 pg/dL) altered success rates. In patients with MGD, a subsequent gland identified was larger than the index gland in 23%. Ninety-eight percent of BE patients were cured of 1° HPT. Conclusions:This is the largest study to evaluate the prevalence of additional parathyroid pathology in patients who are candidates for LE. Limitations in localizing studies and IOPTH fail to identify MGD in at least 16% of patients, risking future recurrence.

Cryoablation, Percutaneous Alcohol Injection, and Radiofrequency Ablation for Treatment of Neuroendocrine Liver Metastases

Abstract. Neuroendocrine liver metastases are associated with slow clinical progression, prolonged patient survival, and symptoms of hormone oversecretion. Although surgical resection is the gold standard of treatment, most of the patients are not candidates for resection, and the 5-year survival of patients with neuroendocrine liver metastases is 11% to 40%. Cryotherapy, percutaneous alcohol injection, and radiofrequency thermal ablation are among the alternative regional treatment options available for these patients. The current role of these treatment options for neuroendocrine liver tumors are discussed in this review. Cryosurgery is the classic technique for local tumor destruction, mostly performed with open surgery. There has been limited experience with percutaneous alcohol injection for neuroendocrine liver metastasis. Radiofrequency thermal ablation is a relatively new modality that can be performed percutaneously or laparoscopically, and encouraging results have been obtained with it for treatment of neuroendocrine liver metastases.

Laparoscopic radiofrequency ablation of primary and metastaticliver tumors

AbstractBackground: Radiofrequency thermal ablation is a new technology for the local destruction of liver tumors. Since we first described laparoscopic radiofrequency ablation (LRFA) for the treatment of liver tumors, much has been learned about patient selection, laparoscopic ultrasound (LU) guided placement of the ablation catheter, monitoring of the ablation process, and patient follow-up. Methods: Since January 1996 we have performed LRFA of 250 tumors in 67 patients including 85 adenocarcinomas, 107 neuroendocrine tumors, 34 sarcomas, 1 melanoma, and 11 hepatomas. We used LU to guide placement of the ablation catheter and to monitor the ablation process. Most of the patients had two trocars (camera and laparoscopic ultrasound) with the 15-gauge ablation catheter (RITA Medical Systems, Mountain View, CA, USA) placed percutaneously. Results: The LRFA procedure was completed successfully in all patients, with 1 to 14 lesions per patient, ranging in size from 0.5 to 10 cm in diameter. The entire liver could be examined by LU via right subcostal ports. Criteria for successful ablation were 5-min ablation times at 100°C with 1-min cool-down temperatures of 60° to 70°C. Outgassing of dissolved nitrogen, monitored by ultrasound, was useful in confirming the zone of ablation. Intralesional color-flow Doppler, seen before ablation, was eliminated after ablation. Placement of the grounding pad closer to the lesion on the back rather than the thigh resulted in more efficient energy delivery to the tumor. Lesions larger than 3 cm in diameter required overlapping ablations to achieve a 1-cm margin of normal liver. Most patients required overnight hospitalization, with no coagulopathy or electrolyte disturbances noted. Conclusions: The LRFA procedure is a novel, minimally invasive technique for treatment of liver tumors that have failed conventional therapy. This study documents the technical aspects of targeting lesions and performing reproducible zones of ablation. Familiarity with these techniques should lead to more widespread application.

Factors contributing to negative parathyroid localization: an analysis of 1000 patients.

BACKGROUND Localizing studies are the key for determining the optimal surgical strategy in patients with primary hyperparathyroidism (HP). Most of the data in the literature are retrospective in nature and from analysis on a per patient basis. This is a prospective study looking at the characteristics of the patient and the gland that determine the likelihood of an abnormal parathyroid to be detected by ultrasonography (US) and sestamibi scan (MIBI). METHODS This is a prospective analysis of 1000 consecutive patients with HP who underwent parathyroidectomy at a tertiary care center. The study group included HP with single gland disease (63%), double adenoma (15%), as well as hyperplasia (15%), familial HP (2%), and secondary/tertiary HP (6%). All patients underwent surgeon-performed neck US followed by MIBI scan. Univariate logistic regression and multivariate analyses were performed on pre- and intraoperative variables. RESULTS A total of 1845 abnormal glands were analyzed. Overall, US was superior to MIBI for the detection of abnormal glands in all subgroups. On multivariate analysis, body mass index (BMI), gland size, and gland volume were the statistically significant independent factors predicting detection by both US and MIBI in primary HP. The sensitivity of US was better for single gland disease than for multigland disease in primary HP, but the sensitivity of MIBI was similar in both groups. For a given size, hyperplastic glands in primary HP imaged less well with US and MIBI than in familial or secondary/tertiary HP. CONCLUSION This prospective study demonstrates that BMI and gland size independently predict accurate detection of abnormal parathyroid glands by US and MIBI in sporadic primary HP. Understanding the factors that affect the accuracy of parathyroid localization tests will allow the surgeon to develop a successful surgical strategy in a given patient.

Robotic versus laparoscopic resection of liver tumours

BACKGROUND There are scant data in the literature regarding the role of robotic liver surgery. The aim of the present study was to develop techniques for robotic liver tumour resection and to draw a comparison with laparoscopic resection. METHODS Over a 1-year period, nine patients underwent robotic resection of peripherally located malignant lesions measuring <5 cm. These patients were compared prospectively with 23 patients who underwent laparoscopic resection of similar tumours at the same institution. Statistical analyses were performed using Students t-test, χ(2) -test and Kaplan-Meier survival. All data are expressed as mean ± SEM. RESULTS The groups were similar with regards to age, gender and tumour type (P= NS). Tumour size was similar in both groups (robotic -3.2 ± 1.3 cm vs. laparoscopic -2.9 ± 1.3 cm, P= 0.6). Skin-to-skin operative time was 259 ± 28 min in the robotic vs. 234 ± 17 min in the laparoscopic group (P= 0.4). There was no difference between the two groups regarding estimated blood loss (EBL) and resection margin status. Conversion to an open operation was only necessary in one patient in the robotic group. Complications were observed in one patient in the robotic and four patients in the laparoscopic groups. The patients were followed up for a mean of 14 months and disease-free survival (DFS) was equivalent in both groups (P= 0.6). CONCLUSION The results of this initial study suggest that, for selected liver lesions, a robotic approach provides similar peri-operative outcomes compared with laparoscopic liver resection (LLR).

Comparison of laparoscopic transabdominal lateral versus posterior retroperitoneal adrenalectomy

BACKGROUND For the past 14 years, we have been performing laparoscopic adrenalectomy via the lateral transabdominal as well as the posterior retroperitoneal approach. The aim of this study is to describe patient selection criteria for each approach with comparison of perioperative outcomes. METHODS In patients with smaller tumors, low body mass index (BMI), history of previous abdominal operations, appropriate body habitus, and bilateral pathology, we have performed preferentially the posterior approach. Data regarding clinical pathology, tumor size, BMI, estimated blood loss (EBL), operating time (OT), morbidity, mortality, and duration of stay were analyzed retrospectively. Data are expressed as mean +/- standard error of the mean (SEM). RESULTS One hundred seventy-two laparoscopic adrenalectomy procedures were performed in 159 patients between 1994 and 2008. The lateral approach was used in 69 patients (right side: 39%, left side: 55%, bilateral: 6%) and the posterior approach in 90 patients (right side: 42%, left side: 48%, bilateral: 10%). The incidence of prior abdominal surgery was greater in the posterior group (26% vs 19%, NS). The lateral approach was used in 9% (3/34) of aldosteronoma, 38% (9/24) of Cushings disease/syndrome, 47% (18/38) of nonsecreting cortical adenoma, 66% (23/35) of pheochromocytoma, 41% (7/17) of malignant lesions, and 73% (8/11) of others. Thirty percent of the bilateral adrenalectomies were performed via lateral and 70% via posterior approach. Two patients in the posterior approach were converted to the laparoscopic lateral approach, and 2 patients in the lateral approach were converted to open. Overall, patient age and sex were similar between groups. BMI was higher in patients undergoing adrenalectomy via lateral vs posterior approach (32.4 vs 28.4; P = .005). Tumor size was larger than 6 cm in 11 (16%) and 1 (1%) of the patients in the lateral and posterior groups, respectively. On univariate analysis, mean OT for lateral and posterior approaches was similar for unilateral cases (157 +/- 7 vs 138 +/- 6 min, respectively; P = NS). This was also true on multivariate analysis when corrected for patient selection factors. EBL was 35 +/- 7 mL for lateral versus 25 +/- 6 mL for posterior approach (P = .05). The duration of stay in lateral and posterior approaches was 1 day in 56% vs 82%, 2 days in 29% vs 13%, and more than 2 days in 15% vs 5% of the patients, respectively. Two patients in the lateral group died postoperatively because of cardiac and pulmonary causes, and 2 patients in the posterior group developed temporary neuralgia. CONCLUSION This series compares 2 different approaches for laparoscopic adrenalectomy. Our study shows that the lateral and posterior techniques have a similar peri-operative outcome when patients are selected for each option based on certain criteria.

National Trends in Parathyroid Surgery from 1998 to 2008: A Decade of Change

BACKGROUND The introduction of limited explorations (LE) for parathyroidectomy broadened the management possibilities for hyperparathyroidism. We sought to document this evolution of change in parathyroid surgery. STUDY DESIGN Members of the American Association of Endocrine Surgeons and the American College of Surgeons were sent a 49-question survey, and 256 surgeons, accounting for 46% of parathyroid operations nationwide, responded. Associations derived from questionnaire data were tested for significance using chi-square and Kruskal-Wallis methods. RESULTS Currently, 10% of surgeons practice bilateral neck exploration, 68% practice LE, and 22% have a mixed practice. Five years ago, these percentages were, respectively, 26%, 43%, and 31%; and 10 years ago they were 74%, 11%, and 15%. Shift to LE was greatest among endocrine surgeons, high-volume surgeons, and surgeons trained by mentors who practiced LE. A focal, single-gland examination under general anesthesia and 23-hour observation are preferred by most surgeons. Half of all general surgeons, in contrast to fewer than 10% of endocrine surgeons, never monitor parathyroid hormone intraoperatively, even with LE. Dramatic differences were apparent among subsets of surgeons in operative volumes, indications for bilateral neck exploration, followup care, expertise with ultrasound and sestamibi, and perceptions of cure and complication rates. Evidence-based literature and guidance from surgical societies had the greatest influence on the decision to practice LE. CONCLUSIONS This survey formally documents the evolution of practice patterns in parathyroid surgery over the last decade. Although LE has achieved wide acceptance, surgical management of hyperparathyroidism has become increasingly disparate. This trend may highlight a need to define best-practice guidelines.