The impact of laparoscopic bariatric workshops on the practice patterns of surgeons.

BACKGROUND: This study was designed to evaluate the impact of a 2-day laparoscopic bariatric workshop on the practice patterns of participating surgeons. METHODS: From October 1998 to June 2002, 18 laparoscopic bariatric workshops were attended by 300 surgeons. Questionnaires were mailed to all participants. RESULTS: Responses were received from 124 surgeons (41%), among whom were 56 bariatric surgeons (open) (45%), 30 advanced laparoscopic surgeons (24%), and 38 surgeons who performed neither bariatric nor advanced laparoscopic surgery (31%). The questionnaire responses showed that 46 surgeons (37%) currently are performing laparoscopic gastric bypass (LGB), 38 (31%) are performing open gastric bypass, and 39 (32%) are not performing bariatric surgery. Since completion of the course, 46 surgeons have performed 8,893 LGBs (mean, 193 cases/surgeon). Overall, 87 of the surgeons (70%) thought that a limited preceptorship was necessary before performance of LGB, yet only 25% underwent this additional training. According to a poll, the respondents thought that, on the average, 50 cases (range, 10-150 cases) are needed for a claim of proficiency. CONCLUSION: Laparoscopic bariatric workshops are effective educational tools for surgeons wishing to adopt bariatric surgery. Open bariatric surgeons have the highest rates of adopting laparoscopic techniques and tend to participate in more adjunctive training before performing LGB. There was consensus that the learning curve is steep, and that additional training often is necessary. The authors propose a mechanism for post-residency skill acquisition for advanced laparoscopic surgery.

Repair of ventral hernias in morbidly obese patients undergoing laparoscopic gastric bypass should not be deferred.

BACKGROUND: There is no consensus regarding the optimal treatment of ventral hernias in patients who present for weight loss surgery. METHODS: Medical records of consecutive morbidly obese patients who underwent laparoscopic Roux-en-Y (LRYGB) gastric bypass with a secondary diagnosis of ventral hernia were reviewed. Only patients who were beyond 6 months of follow-up were included. RESULTS: The study population was 85 patients. There were three groups of patients according to the method of repair: primary repair (59), small intestine submucosa (SIS) (12), and deferred treatment (14). Average follow-up was 26 months. There was a 22% recurrence in the primary repair group. There were no recurrences in the SIS group. Five of the patients in the deferred treatment group (37.5%) presented with small bowel obstruction due to incarceration. CONCLUSION: Biomaterial mesh (SIS) repair of ventral hernias concomitant with LRYGB resulted in the most favorable outcome albeit having short follow-up. Concomitant primary repair is associated with a high rate of recurrence. All incarcerated ventral hernias should be repaired concomitant with LRYGB, as deferment may result in small bowel obstruction.

Immunotherapy of metastasis.

This article provides a basic overview of tumor immunology vaccines, current vaccine trials, and future directions of vaccine strategies for the treatment of metastatic cancers. As dendritic cells are the most potent antigen-presenting cell and central to the regulation, maturation, and maintenance of a cellular immune response to cancer, these cells may be crucial to tumor vaccine strategies. Peptide-based strategies and monoclonal antibodies also have been used with some success in developing a tumor-specific response. Methods promoting a more effective immune response and maintaining T-cell survival through administration of adjuvant cytokines, synthetically modified antigens, and various other immunoadjuvants are discussed.

Interleukin-18 (IL-18) synergizes with IL-2 to enhance cytotoxicity, interferon-gamma production, and expansion of natural killer cells.

We investigated the in vitro effects of combining interleukin-18 (IL-18) and IL-2 on human lymphocytes. The combined use of these two cytokines synergistically enhanced the proliferation, cytolytic activity, and interferon-gamma production of peripheral blood mononuclear cells. Phenotypic analysis revealed a preferential expansion of CD56+CD3- cells and an up-regulation of IL-2 receptor-alpha expression on natural killer cells. Isolated natural killer cells showed a substantial increase in proliferation and cytotoxicity compared with CD4+ and CD8+ T cells. The combined use of IL-18 and IL-2 should be considered a viable strategy to induce an antitumor response in vivo.

The dendritic cell and human cancer vaccines.

Over the past ten years, the identification of the critical role that dendritic cells (DCs) play in stimulating a specific immune response has led to their use in cancer and HIV therapy. Interesting responses have been reported but the most effective approach and the duration of these responses are still unclear. The quality of DCs, the means by which tumor antigens are delivered to DCs and the problems associated with monitoring the immune response have made individual studies difficult to compare. Much work is still needed to determine the role that DC-based cancer vaccines will have, the most effective way to deliver DCs to patients and the most relevant antigens to provide to DCs.