[The importance of microbiological results for the treatment of complicated appendicitis-a monocentric case-control study]. / Die Bedeutung mikrobiologischer Ergebnisse für die Therapie der komplizierten Appendizitis ­ eine monozentrische Fall-Kontroll-Studie.

BACKGROUND: Patients with complicated appendicitis frequently develop postoperative septic complications. There are no uniform standards for the choice of perioperative antibiotic prophylaxis and the duration of postoperative antibiotic treatment. The purpose of this study was to investigate associations between microbiological samples and postoperative complications. METHODS: Patients with appendectomy and positive intraoperative swabs during 2013-2018 were included in this case-control study. Pathogen classes and their resistance patterns were evaluated in initial and follow-up swabs and compared in each of the groups with and without complications. RESULTS: A total of 870 patients underwent surgery during the period studied. Pathogen detection succeeded in 102 of 210 cases (48.6%) with suspected bacterial peritoneal contamination. Conversion from laparoscopic to open intra-abdominal perforation and the presence of an abscess were independent risk factors for wound infections in the multivariate analysis. The combination of different classes of pathogens resulted in significantly increased overall resistance to ampicillin/sulbactam in both the initial swabs (57%) and the follow-up swabs (73%). Resistant E. coli strains combined with certain anaerobes were also regularly detected in postoperative intra-abdominal abscesses. Piperacillin/tazobactam was effective against 83% of positive swabs in our resistance tests. CONCLUSION: Surgical treatment for complicated appendicitis remains the central therapeutic column. A regular review of the existing resistance patterns in perforated appendicitis can help to adjust and improve antibiotic treatment. Piperacillin/tazobactam should be used cautiously as a reserve antibiotic. A valid alternative is second or third generation cephalosporins in combination with metronidazole.

Meta-analysis of outcomes following resection of the primary tumour in patients presenting with metastatic colorectal cancer.

BACKGROUND: It is not clear whether resection of the primary tumour (when there are metastases) alters survival and/or whether resection is associated with increased morbidity. This systematic review and meta-analysis assessed the prognostic value of primary tumour resection in patients presenting with metastatic colorectal cancer. METHODS: A systematic review of MEDLINE/PubMed was performed on 12 March 2016, with no language or date restrictions, for studies comparing primary tumour resection versus conservative treatment without primary tumour resection for metastatic colorectal cancer. The quality of the studies was assessed using the MINORS and STROBE criteria. Differences in survival, morbidity and mortality between groups were estimated using random-effects meta-analysis. RESULTS: Of 37 412 initially screened articles, 56 retrospective studies with 148 151 patients met the inclusion criteria. Primary tumour resection led to an improvement in overall survival of 7·76 (95 per cent c.i. 5·96 to 9·56) months (risk ratio (RR) for overall survival 0·50, 95 per cent c.i. 0·47 to 0·53), but did not significantly reduce the risk of obstruction (RR 0·50, 95 per cent c.i. 0·16 to 1·53) or bleeding (RR 1·19, 0·48 to 2·97). Neither was the morbidity risk altered (RR 1·14, 0·77 to 1·68). Heterogeneity between the studies was high, with a calculated I2 of more than 50 per cent for most outcomes. CONCLUSION: Primary tumour resection may provide a modest survival advantage in patients presenting with metastatic colorectal cancer.

[Resection for advanced pancreatic cancer following multimodal therapy]. / Resektion beim fortgeschrittenen Pankreaskarzinom nach multimodaler Vorbehandlung.

Pancreatic cancer patients presenting with borderline resectable or locally advanced unresectable tumors remain a therapeutic challenge. Despite the lack of high quality randomized controlled trials, perioperative neoadjuvant treatment strategies are often employed for this group of patients. At present the FOLFIRINOX regimen, which was established in the palliative setting, is the backbone of neoadjuvant therapy, whereas local ablative treatment, such as stereotactic irradiation and irreversible electroporation are currently under investigation. Resection after modern multimodal neoadjuvant therapy follows the same principles and guidelines as upfront surgery specifically regarding the extent of resection, e.g. lymphadenectomy, vascular resection and multivisceral resection. Because it is still exceedingly difficult to predict tumor response after neoadjuvant therapy, a special treatment approach is necessary. In the case of localized stable disease following neoadjuvant therapy, aggressive surgical exploration with serial frozen sections at critical (vascular) margins might be necessary to minimize the risk of debulking procedures and maximize the chance of a curative resection. A multidisciplinary and individualized approach is mandatory in this challenging group of patients.