[Fluid therapy and surgical outcomes after low anterior resection]

INTRODUCTION

Fluid therapy is a fundamental component of surgical care. Recent data regarding fluid restriction has shown an association with improved outcomes. The aim of this study is to determine whether the use of restrictive approaches in perioperative fluid administration improves patient outcomes following low anterior resection.

MATERIAL AND METHODS

89 patients undergoing low anterior resection included in this study were divided by the median 14.9 mL/kg/h into group A (7.4-14.7 mL/kg/h) and group B (14.9-36.8 mL/kg/h) within intraoperative fluid administration, and by the median 3.3 mL/kg/h into group C (2.0-3.3 mL/kg/h) and group D (3.3-6.9 mL/kg/h) for fluid administration on the day of surgery. The main outcomes measured were cardiac and pulmonary complications, the incidence of anastomotic leak and wound infections, gastrointestinal function recovery, laboratory inflammatory markers and the length of hospital stay.

RESULTS

The restricted perioperative fluid regimen significantly reduced the risk of pleural effusion and anastomotic leak in patients after low anterior resection. The overall incidence of anastomotic leak was 9.0%. Another significant risk factor for anastomotic leak was neoadjuvant radiochemotherapy (15.9% vs. 2.2%, p=0.03).

CONCLUSION

The restricted perioperative fluid regimen reduces postoperative morbidity in patients after low anterior resection. Hospital stay remains unchanged.

Co-seeded Er3+:Yb3+ single frequency fiber amplifier with 60 W output power and over 90% TEM(00) content

We report on the design and fabrication of an Er(3+):Yb(3+) triple clad fiber and on the power scaling of a single frequency fiber amplifier at 1.5 μm based on that fiber. In addition, we report on mode content measurements in order to reveal the overlap of the amplifier output with the TEM(00) mode. The triple clad design was used to enable high output power levels, a good slope efficiency and an excellent beam quality. A maximum single frequency output power of 61 W at 1.5 μm could be achieved with the aid of the co-seeding method, which was used to suppress parasitic processes at 1.0 μm. With a scanning ring cavity the mode content of the amplifier output was analyzed with respect to the TEM modes. For all output power levels the TEM(00) content was above 90%.

[Dissection and coagulation technique in thyroid surgery - is it the key to a successful outcome?]

INTRODUCTION

This study analyzes the impact of coagulation instrument devices used during thyroid gland removal in which careful dissection and perfect haemostasis represent very important aspects. Standard electrocautery is compared to the use of bipolar forceps. The aim is to determine whether the use of different modes of coagulation is the key to the frequency and severity of postoperative complications following total thyroidectomy.

MATERIAL AND METHODS

This study included 82 patients undergoing total thyroidectomy with haemostasis by conventional suture ligation technique combined with monopolar electrocauterization and 36 patients undergoing total thyroidectomy with complete haemostasis by bipolar forceps. The main outcomes measured were postoperative bleeding, recurrent laryngeal nerve palsy and post-thyroidectomy hypocalcaemia and hypoparathyroidism. Patients were followed up for 6 months.

RESULTS

The results of our study showed that the use of bipolar forceps for vessel ligation in thyroid surgery is as safe and effective as the use of monopolar electrocautery and ligatures. Statistical analysis showed no significant differences in the rate of the individual postoperative complications between the two cohorts. Complication rates in the entire cohort were comparable with data reported in the literature.

CONCLUSION

Both approaches are safe and reliable and both represent valid options. The choice might depend on the surgeons preferences and experience, the nature of the thyroid condition and the nature and extent of the surgical procedure.

Acute WNT signalling activation perturbs differentiation within the adult stomach and rapidly leads to tumour formation

A role for WNT signalling in gastric carcinogenesis has been suggested due to two major observations. First, patients with germline mutations in adenomatous polyposis coli (APC) are susceptible to stomach polyps and second, in gastric cancer, WNT activation confers a poor prognosis. However, the functional significance of deregulated WNT signalling in gastric homoeostasis and cancer is still unclear. In this study we have addressed this by investigating the immediate effects of WNT signalling activation within the stomach epithelium. We have specifically activated the WNT signalling pathway within the mouse adult gastric epithelium via deletion of either glycogen synthase kinase 3 (GSK3) or APC or via expression of a constitutively active β-catenin protein. WNT pathway deregulation dramatically affects stomach homoeostasis at very short latencies. In the corpus, there is rapid loss of parietal cells with fundic gland polyp (FGP) formation and adenomatous change, which are similar to those observed in familial adenomatous polyposis. In the antrum, adenomas occur from 4 days post-WNT activation. Taken together, these data show a pivotal role for WNT signalling in gastric homoeostasis, FGP formation and adenomagenesis. Loss of the parietal cell population and corresponding FGP formation, an early event in gastric carcinogenesis, as well as antral adenoma formation are immediate effects of nuclear β-catenin translocation and WNT target gene expression. Furthermore, our inducible murine model will permit a better understanding of the molecular changes required to drive tumourigenesis in the stomach.

Single-stage revision for peri-prosthetic shoulder infection

There have been only a few small studies of patients with an infected shoulder replacement treated with a single-stage exchange procedure. We retrospectively reviewed 35 patients (19 men and 16 women) with a peri-prosthetic infection of the shoulder who were treated in this way. A total of 26 were available for clinical examination; three had died, two were lost to follow-up and four patients had undergone revision surgery. The mean follow-up time was 4.7 years (1.1 to 13.25), with an infection-free survival of 94%.

The organisms most commonly isolated intra-operatively were Staphylococcus epidermidis and Propionibacterium acnes; two patients developed a recurrent infection. Three different types of prosthesis were used: a hemiarthroplasty, a hemiarthroplasty with a bipolar head and reverse prosthesis. The mean Constant-Murley score at final follow-up was 43.3 (14 to 90) for patients with a hemiarthroplasty, 56 (40 to 88) for those with a hemiarthroplasty with a bipolar head and 61 (7 to 90) for those with a reverse prosthesis. The mean hospital stay was 10.6 days (5 to 29).

Single-stage exchange is a successful and practical treatment for patients with peri-prosthetic infection of the shoulder.

Cite this article: Bone Joint J 2013;95-B:391–5.

EGFR pathway biomarkers in erlotinib-treated patients with advanced pancreatic cancer: translational results from the randomised, crossover phase 3 trial AIO-PK0104

Background:

We aimed to identify molecular epidermal growth factor receptor (EGFR) tissue biomarkers in pancreatic cancer (PC) patients treated with the anti-EGFR agent erlotinib within the phase 3 randomised AIO-PK0104 study.

Methods:

AIO-PK0104 was a multicenter trial comparing gemcitabine/erlotinib followed by capecitabine with capecitabine/erlotinib followed by gemcitabine in advanced PC; primary study end point was the time-to-treatment failure after first- and second-line therapy (TTF2). Translational analyses were performed for KRAS exon 2 mutations, EGFR expression, PTEN expression, the EGFR intron 1 and exon 13 R497K polymorphism (PM). Biomarker data were correlated with TTF, overall survival (OS) and skin rash.

Results:

Archival tumour tissue was available from 208 (74%) of the randomised patients. The KRAS mutations were found in 70% (121 out of 173) of patients and exclusively occurred in codon 12. The EGFR overexpression was detected in 89 out of 181 patients (49%) by immunohistochemistry (IHC), and 77 out of 166 patients (46%) had an EGFR gene amplification by fluorescence in-situ hybridisation (FISH); 30 out of 171 patients (18%) had a loss of PTEN expression, which was associated with an inferior TTF1 (first-line therapy; HR 0.61, P=0.02) and TTF2 (HR 0.66, P=0.04). The KRAS wild-type status was associated with improved OS (HR 1.68, P=0.005); no significant OS correlation was found for EGFR–IHC (HR 0.96), EGFR–FISH (HR 1.22), PTEN–IHC (HR 0.77), intron 1 (HR 0.91) or exon 13 R497K PM (HR 0.83). None of the six biomarkers correlated with the occurrence of skin rash.

Conclusion:

The KRAS wild-type was associated with an improved OS in erlotinib-treated PC patients in this phase 3 study; it remains to be defined whether this association is prognostic or predictive.

[Anaplastic carcinoma of the thyroid gland]

INTRODUCTION

The characteristics of anaplastic carcinoma, its biological properties, incidence and possibilities of therapeutic influence are described in the article.

MATERIAL AND METHODS

The authors present a cohort of patients with anaplastic carcinoma of the thyroid gland (ATC) who were operated on at the Department of Surgery during the last 5 years.

RESULTS

The destiny of all the patients with histologically confirmed anaplastic carcinoma is followed, the survival period is evaluated. With regard to the small patient cohort there was no further statistical processing.

CONCLUSION

The role of the surgeon in the treatment of anaplastic carcinoma as well as the necessity of the multimodal way of treatment is evaluated.

[Mucinous neoplasms of the vermiform appendix, Pseudomyxoma peritonei, and the new WHO classification]

Mucinous neoplasms of the appendix are rare tumors, some of them characterized by an enigmatic discrepancy between a benign morphologic appearance and an aggressive biologic potential, associated with a poor prognosis and high mortality. The clinical picture of pseudomyxoma peritonei is, with few exceptions, caused by mucinous appendiceal neoplasms and differs in many aspects from usual peritoneal carcinomatosis. The controversy regarding terminology, diagnostic criteria, classification and therapy of these tumors has lasted for decades. The revised edition of the World Health Organization Classification of Tumors of the Digestive System proposes a uniform reporting system for mucinous appendiceal neoplasms and the peritoneal disease associated with it, thereby creating a comparable basis for pathological diagnosis, clinical therapy and further scientific studies.

[Gastrointestinal mixed adenoneuroendocrine carcinomas. An attempt at classification of mixed cancers]

Mixed adenoneuroendocrine carcinomas (MANECs) are a challenge for the diagnostics and the concept of a histogenetic tumor typing. They are classified into three malignant subgroups: high grade malignant MANECs combine an adenoma or adenocarcinoma with a small cell or large cell neuroendocrine carcinoma, intermediate grade malignant MANECs consist of a neuroendocrine tumor (NET grade 1 or 2), often a globlet cell carcinoid and a poorly differentiated adenocarcinoma or diffuse carcinoma of signet ring cell type. The prototype of a low grade malignant MANEC is the globlet cell carcinoid. Molecular analysis indicates a common clonal origin of the different components in MANECs. The prognosis is determined by the most aggressive tumor component. The pathogenesis of MANECs is apparently a sequence of increasing malignant transformation which leads either from an adenoma/adenocarcinoma to a small or large cell neuroendocrine carcinoma or from a neuroendocrine tumor (NET), often a globlet cell carcinoid to a poorly differentiated adenocarcinoma or a diffuse carcinoma of signet ring cell type.

Prophylactic intravenous nimodipine treatment in skull base surgery: pharmacokinetic aspects

BACKGROUND

Nimodipine is primarily used in subarachnoid hemorrhage (SAH). Clinical trials revealed also a beneficial effect of prophylactic nimodipine treatment on cranial nerve functions following vestibular schwannoma surgery.

OBJECTIVE

The unknown pharmacokinetics of prophylactically administered nimodipine were investigated.

METHODS

Samples were taken from 27 patients with skull base lesions. Prophylactic intravenous nimodipine infusion was started 5.8-25.8 h (mean 17.9 h) before surgery. Nimodipine concentrations were determined in serum (intra- and postoperatively), cerebrospinal fluid (CSF) (intraoperatively), and tissue samples.

RESULTS

Wide interindividual differences were observed. Mean concentrations for nimodipine were 46.9 ng/ml (SD: 6.4; min. 4.1 and max. 92.7 ng/ml) in intraoperative serum, 73.2 ng/ml (SD: 16.7; min. 6.6 and max. 253 ng/ml) in postoperative serum and 8.3 ng/ml (SD: 1.5; min. 1.0 und max. 29.7 ng/ml) in intraoperative CSF. The correlation between intra- and postoperative serum (p=0.004, r=0.560) and between intra-operative serum and CSF concentration (p=0.003, r=0.567) were statistically significant. Furthermore the correlation between intraoperative serum concentration and concentrations collected from vestibular nerves was high (r=0.711), but not statistically significant (p=0.178).

CONCLUSIONS

Interindividually, continously administered intravenous nimodipine produces considerably variable serum levels. Controls of nimodipine serum concentrations may be useful to optimize nimodipine medication in skull base surgery and in the management of SAH. The serum nimodipine level is a useful marker for CSF and intracranial nerve tissue concentrations of nimodipine.

FOLFIRI plus cetuximab versus FOLFIRI plus bevacizumab as first-line treatment for patients with metastatic colorectal cancer-subgroup analysis of patients with KRAS: mutated tumours in the randomised German AIO study KRK-0306

BACKGROUND

The AIO KRK-0306 trial compares the efficacy of infusional 5-fluorouracil, folinic acid, irinotecan (FOLFIRI) plus cetuximab with FOLFIRI plus bevacizumab in first-line treatment of metastatic colorectal cancer (mCRC). In October 2008, an amendment terminated the inclusion of patients with KRAS-mutated tumours. This subgroup of patients is evaluated in the present analysis, while the study is ongoing for patients with KRAS wild-type tumours.

METHODS

Patients were randomly assigned to FOLFIRI (Tournigand regimen) every 2 weeks plus cetuximab (400 mg/m2 day 1, followed by 250 mg/m2 weekly=arm A) or bevacizumab (5 mg/kg every 2 weeks=arm B). Among 336 randomised patients, KRAS mutation was demonstrated in 100 assessable patients. The primary study end point was objective response rate (ORR).

RESULTS

ORR was 44% [95% confidence interval (CI) 29% to 59%] in arm A versus 48% (95% CI, 33% to 62%) in arm B. Progression-free survival was 7.5 versus 8.9 months (hazard ratio: 1.0) and overall survival was 22.7 versus 18.7 months (hazard ratio: 0.86) in arms A versus B, respectively.

CONCLUSIONS

This is the first head to head comparison of cetuximab versus bevacizumab in first-line treatment of mCRC. In the present evaluation of patients with KRAS-mutated tumours, neither strategy demonstrated a clearly superior outcome.

Functional nuclear organization of transcription and DNA replication: a topographical marriage between chromatin domains and the interchromatin compartment

We studied the nuclear topography of RNA transcription and DNA replication in mammalian cell types with super-resolution fluorescence microscopy, which offers a resolution beyond the classical Abbe/Raleigh limit. Three-dimensional structured illumination microscopy (3D-SIM) demonstrated a network of channels and wider lacunas, called the interchromatin compartment (IC). The IC starts at nuclear pores and expands throughout the nuclear space. It is demarcated from the compact interior of higher-order chromatin domains (CDs) by a 100-200-nm thick layer of decondensed chromatin, termed the perichromatin region (PR). Nascent DNA, nascent RNA, RNA polymerase II (RNA Pol II), as well as histone modifications for transcriptionally competent/active chromatin, are highly enriched in the PR, whereas splicing speckles are observed in the interior of the IC. In line with previous electron microscopic evidence, spectral precision distance/position determination microscopy (SPDM) confirmed the presence of RNA Pol II clusters indicative of transcription factories. Still, a substantial part of transcription apparently takes place outside of such factories. Previous electron microscopic evidence has suggested that the functional nuclear organization of DNA replication depends on brownian movements of chromatin between the CD interior and the PR. As an incentive for future studies, we hypothesize that such movements also take place during transcription, i.e., only the actually transcribed part of a gene may be located within the PR, whereas its major part, including previously or later transcribed sequences, is embedded in a higher-order chromatin configuration in the interior of the CD.