Analysis of laparoscopic laser liver resection in standardized porcine model.

BACKGROUND: Hepatocellular carcinoma is a highly prevalent and lethal primary neoplasia of the liver and metastases of other malignancies affect most frequently the liver. Minimally invasive surgical approach for liver resections is advancing. Dissection of liver parenchyma by laparoscopic technique remains challenging and new technologies are in need. Therefore, we asked whether it is feasible to dissect liver tissue comparably in terms of speed and hemostasis with a non-contact 1.9-µm cw-laser device and whether there are differences in the postoperative healing process compared to a gold standard device (ultrasound aspirator) in an experimental model. METHODS: Laparoscopic laser and ultrasound aspirator standardized partial liver resections were performed in seven pigs. Resection time, hemostasis time, and blood loss were evaluated. After at least 10 days, representative specimen of the resection areas was collected via re-laparoscopy and biopsy and side effects like hematoma, abscess, or bilioma were noted. Histologically, coagulation necrosis margin, granulation tissue zone, tissue fibrosis, and giant cell count were analyzed. RESULTS: Laparoscopic laser liver resection was three times faster compared to the laparoscopic ultrasound aspirator. Blood loss was equal in both groups. No side effects like hematoma or bilioma occurred. Histologically, specimen showed the same expansion of coagulation necrosis zone and granulation tissue. Fibrotic scar could be determined in three cases in both groups, respectively. However, giant cell count was significant higher in the laser resection group. CONCLUSIONS: The 1.9-µm cw-laser device enables a safe and fast liver resection in an experimental pig model compared to a gold standard (ultrasound aspirator) laparoscopic liver resection method. Wound healing is not interfered by laser liver resection.

The application of cold-plasma coagulation on the visceral pleura results in a predictable depth of necrosis without fistula generation.

A technique for the safe transfer of electric energy to the pulmonary surface for the potential evaporation of malignant tumours is non-existent to date. By conducting the current study, we wanted to generate data on the potential beneficiary effects and complications of using cold-plasma coagulation on the pulmonary surface. Cold-plasma coagulation was applied to the pulmonary surface in eight female mini-pigs via a thoracoscopic access. After 12 days, we performed a re-thoracoscopy on the contralateral side. After a further 12 days, we performed a median sternotomy and did cold-plasma coagulation on previously untreated areas of either lung. No pulmonary fistulas were detected. In two of the eight pigs, we found a localized chronic pneumonia. None of the pigs died during the course of the study. Morbidity was also low with two pigs refusing food intake, one pig with dyspnoea after difficult intubation and one pig coughing. All events were self-limited and occurred only on post-operative Day 1. The treatment effect was almost linear and correlated to the generator energy applied. The differences between the effects reached statistical significance (P < 0.05). The application of cold-plasma coagulation to the pulmonary surface is safe in pigs. A potential clinical application of this technique is treatment of malignant pleural mesothelioma.

Multivisceral and standard resections in colorectal cancer.

PURPOSE: The current study was designed to identify prognostic factors for long-term survival in patients with advanced colorectal cancer in a consecutive cohort. METHODS: A total of 123 patients were operated because of T4 colorectal cancer between 1 January 2002 and 31 December 2008 in the Clinic of Surgery, UK-SH Campus Luebeck. RESULTS: A total of 78 patients underwent a multivisceral resection. The postoperative morbidity was elevated in the patient group with multivisceral resections (34.6% vs. 26.7%). Nevertheless, we detected no significant differences concerning 30 days mortality (7.7% vs. 8.9%; p = 0.815). The main prognostic factor that reached significance in the multivariate analysis was the possibility to obtain a R0 resection (p < 0.0001) resulting in a 5-year survival rate of 55% for patients with curative resection. There were no statistically significant differences in 5-year survival between multivisceral and non-multivisceral resections (p = 0.608). Also we were not able to detect any significant differences for cancer of colonic or rectal origin (p = 0.839), for laparoscopic vs. open procedures (p = 0.610), and for emergency vs. planned operations (p = 0.674). Moreover, the existence of lymph node metastases was not a predictive factor concerning survival as there was no difference between patients with and without lymph node metastases (p = 0.658). CONCLUSIONS: Multivisceral resections are associated with the same 5-year survival as standard resections. Therefore, the aim to perform a R0 resection should always be the main goal in surgery for colorectal cancer. In planned operations, a laparoscopic approach is justified in selected patients.