Aristotelis Perrakis

University Hospital Magdeburg · Department of Surgery

Simple Summary In the past, the German Cancer Society has implemented a certification program for colorectal cancer centers with the aims of standardizing oncological treatment, endorsing a multidisciplinary approach, and improving the outcomes. However, some critical views have argued that fulfilling the certification requirements alone would not...

Background: Secondary malignant tumors of the pancreas are rare, representing 2–5% of all pancreatic malignancies. Nevertheless, the pancreas is one of the target organs in cases of metastatic clear cell renal cell carcinoma (CCRCC). Additionally, recurrent metastasis may occur. Surgical resection remains the best and prognostically most favorable...

Simple Summary Minimally invasive surgery is a decisive step forward in reducing morbidity and mortality in surgery. In liver surgery, this procedure is already standard for small resections. Complex operations on the liver are only performed in a few experienced centers. ALPPS is a very complex procedure and requires the highest level of expertise...

A study in Germany found appendicoliths in 71 % of acute appendicitis cases, suggesting the prevalence in former studies is underestimated. Improved detection methods revealed higher rates of appendicoliths in complicated cases, correlating with severe outcomes and longer hospital stays, indicating a need for revised diagnostic protocols. DOI: 10....

Transient receptor potential (TRP) channels are strongly associated with colon cancer development and progression. This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TRP channels-associated gene signature, with further validation of signature in real world samples from our hospital treated patient...

Objectives The unexpected global overload of the health system during COVID-19 pandemic has caused changes in management of acute appendicitis worldwide. Whereas conservative treatment was widely recommended, the appendicectomy remained standard therapy in Germany. We aimed to investigate the impact of COVID-19 pandemic on treatment routine for acu...

Introduction Pancreatic cancer is a highly aggressive cancer, and early diagnosis significantly improves patient prognosis due to the early implementation of curative-intent surgery. Our study aimed to implement machine-learning algorithms to aid in early pancreatic cancer diagnosis based on minimally invasive liquid biopsies. Materials and method...

Objectives Rectal prolapse is defined as prolapse of all layers of rectal wallout of the anal sphincter. The aim was to (i) describe the extremely rare combination of a rectal prolapse with colon cancer in an older female patient, (ii) comment on management-specific aspects and (iii) derive some generalizing recommendations by means of a scientific...

Current treatment for glioblastoma includes tumor resection followed by radiation, chemotherapy, and periodic post-operative examinations. Despite combination therapies, patients face a poor prognosis and eventual recurrence, which often occurs at the resection site. With standard MRI imaging surveillance, histologic changes may be overlooked or mi...

Background: The challenges of an adequate, efficient and rational medical treatment and care of patients are always associated with an interprofessional activity of several specialist disciplines. Aim: The spectrum of variable diagnoses and the profile of surgical decision-making with further surgical measures within the framework of senior phys...

Rationale and Objectives Sarcopenia is defined as skeletal muscle loss and can be assessed by cross-sectional imaging. Our aim was to establish the effect of sarcopenia on relevant outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) in curative and palliative settings based on a large patient sample. Materials and Methods MEDLINE lib...

Background Treatment options for metastatic colorectal cancer (CRC) are mostly ineffective. We present new evidence that tumor tissue collagen type X alpha 1 (COL10A1) is a relevant candidate biomarker to improve this dilemma. Methods Several public databases had been screened to observe COL10A1 expression in transcriptome levels with cell lines a...

Zusammenfassung Einleitung Der Einsatz roboterassistierter Operationen verzeichnet in der Viszeralchirurgie gegenwärtig einen stetigen Zuwachs. Im Jahr 2020 hat die COVID-19-Pandemie den klinischen und chirurgischen Alltag unerwartet wesentlich verändert. Wir haben in einer Umfrage den Status der roboterassistierten Viszeralchirurgie in Deutschlan...

Background: Robotic procedures are an integral part of modern liver surgery. However, the advantages of a robotic approach in comparison to the conventional laparoscopic approach are the subject of controversial debate. The aim of this systematic review and meta-analysis is to compare robotic and laparoscopic liver resection with particular attent...

Robotic-assisted procedures gain increasing acceptance for daily surgical routine. However, structured training programs are designed for surgeons with high expertise. Hence, a comprehensive training curriculum was established to ensure a basic competence in robotic abdominal surgery for young surgeons during their residency. The aim of the current...

Purpose To assess the influence of low skeletal muscle mass (LSMM) on post-operative complications in patients with hepatic malignancies grade (Clavien Dindo ≥ 3) undergoing resection. Methods MEDLINE, Cochrane, and SCOPUS databases were screened for associations between sarcopenia and major post-operative complications (≥ grade 3 according to Cla...

Background: Liver failure is a crucial predictor for relevant morbidity and mortality after hepatic surgery. Hence, a good patient selection is mandatory. We use the LiMAx test for patient selection for major or minor liver resections in robotic and laparoscopic liver surgery and share our experience here. Patients and methods: We identified pat...

Background The COVID-19 pandemic caused a global health crisis in 2020. This pandemic also had a negative impact on standard procedures in general surgery. Surgeons were challenged to find the best treatment plans for patients with acute cholecystitis. The aim of this study is to investigate the impact of the COVID-19 pandemic on the outcomes of la...

Background: Transient receptor potential channels (TRPs) have been demonstrated to take on functions in pancreatic adenocarcinoma (PAAD) biology. However, little data are available that validate the potential of TRP in a clinical translational setting. Methods: A TRPs-related gene signature was constructed based on the Cox regression using a TCG...

Limitations in genetic stability and recapitulating accurate physiological disease properties challenge the utility of patient‐derived (PD) cancer models for reproducible and translational research. We have genetically engineered a portfolio of isogenic human induced pluripotent stem cells (hiPSCs) with different pan‐cancer relevant oncoprotein sig...

Background: The implementation of robotics in liver surgery offers several advantages compared to conventional open and laparoscopic techniques. One major advantage is the enhanced degree of freedom at the tip of the robotic tools compared to laparoscopic instruments. This enables excellent vessel control during inflow and outflow dissection of th...

Background To date, the role of low skeletal muscle mass (LSMM) in cholangiocarcinoma (CC) is unclear. Our purpose was to analyze the influence of LSMM on survival in patients with CC treated by surgical resection. Methods MEDLINE, Cochrane, and SCOPUS databases were screened for associations between sarcopenia and survival in CC up to June 2021....

Background: Duodenal gastrointestinal stromal tumors (GIST) are a rare subset of GIST. Their surgical management in this anatomically complex region consists of varied approaches, and the administration of imatinib mesylate (IM) has not been clarified. Methods: We retrospectively reviewed patients with duodenal GIST treated during a 10-year-peri...

Specialty palliative care (PC) clinicians are frequently asked to discuss prognosis with patients and their families. When conveying information about prognosis, PC clinicians need also to discuss the likelihood of prolonged hospitalization, cognitive and functional disabilities, and death. As PC moves further and further upstream, it is crucial th...

Purpose Minimally invasive liver surgery (MILS) is a feasible and safe procedure for benign and malignant tumors. There has been an ongoing debate on whether conventional laparoscopic liver resection (LLR) or robotic liver resection (RLR) is superior and if one approach should be favored over the other. We started using LLR in 2010, and introduced...

Objectives: Indocyanine green (ICG) is a fluorescent dye which was initially used for liver functional assessment. Moreover, it is of value for intraoperative visualization of liver segments and bile ducts or primary and secondary liver tumors. Especially in minimally invasive liver surgery, this is essential to enhance the precision of anatomical...

Appendicitis is an infection to be treated urgently. It is one of the most common causes of acute abdominal pain needing surgical intervention, mainly in younger patients.

Background Minimally invasive liver surgery (MILS) in the treatment of colorectal liver metastases (CRLM) is increasing in incidence. The aim of this work was to present our experience by reporting short-term and long-term outcomes after MILS for CRLM with comparative analysis of laparoscopic (LLS) and robotic liver surgery (RLS). Methods Twenty-f...

Purpose Incisional hernia (IH) is not uncommon after liver transplantation (LT). We investigated the long-term outcome of mesh-based hernia repair using an inlay-onlay technique. Methods Our analysis was based on a prospective collected database of all LT recipients from our hospital over a period of 15 years. We analyzed clinical data including t...

Background: Neuroma of the biliary tree is extremely rare with no more than 100 cases reported so far. They mostly present with obstructive jaundice and have been commonly described after surgery or abdominal trauma. Although involvement of the extrahepatic bile duct is far more common, occurrence in the intrahepatic ducts has not so far been repo...

Introduction The management of locally advanced extremity soft tissue sarcomas, particularly in terms of a limb salvage strategy, represents a challenge, especially in recurrent tumors. In the context of a patient-tailored multimodal therapy, hyperthermic isolated limb perfusion (ILP) is a promising limb-saving treatment option. We report the outco...

Human cytomegalovirus (CMV) remains a major cause of mortality and morbidity in human liver transplant recipients. Anti-CMV therapeutics can be used to prevent or treat CMV in liver transplant recipients, but their toxicity needs to be balanced against the benefits. The choice of prevention strategy (prophylaxis or preemptive treatment) depends on...

Whether sealing the hepatic resection surface after liver surgery decreases morbidity is still unclear. Nevertheless, various methods and materials are currently in use for this procedure. Here, we describe our experience with a simple technique using a mobilized falciform ligament flap in minimally invasive liver surgery (MILS). We retrospectively...

Introduction: Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade malignant mesenchymal tumor of the soft tissue, characterized by slow infiltrative growth and common local recurrence, with rare distant metastases. Patients and methods: We present a retrospective study of nineteen patients who were diagnosed with DFSP and operated at our...

Introduction: Complete mesocolic excision (CME) is generally accepted as state of the art in colon cancer surgery. However, the long-term impact of CME has not been systematically examined. Therefore cohort studies might be a possible way to clarify any differences between conventional resections and CME. Following bilateral cooperation between th...

Mesothelial cyst of the round ligament is a rare finding in females, with only a few cases reported so far. A case of a 25 year old female patient presenting with a palpable mass in her right inguinal region is presented. The preoperative investigation through ultrasound (U/S), computed tomography (CT) and magnetic resonance imaging (MRI) revealed...

Background: Schwannomas of gastrointestinal tract are rare, mostly benign and notably different neoplasms from conventional schwannomas that arise in soft tissue or the central nervous system. These tumors are of clinical importance since they should always be considered in the differential diagnosis of submucosal lesions of gastrointestinal tract...

Focal nodular hyperplasia (FNH) is a common benign liver tumor, which occurs in the vast majority of the cases in young women. FNH represents a polyclonal lesion characterized by local vascular abnormalities and is a truly benign lesion without any potential for malignant transformation. A retrospective single institution analysis of 227 FNH patien...

Background: Complete mesocolic excision (CME) for colonic cancer offers a surgical specimen of higher quality, with higher number of lymph nodes compared to conventional colectomy. However, evidence on oncological outcomes is limited. The aim of the present study is to review recent literature and provide more information regarding the effect of C...

Background Minimally invasive liver surgery is increasing worldwide. The benefit of the robot in this scenario is currently controversially discussed. We compared our robotic cases vs. laparoscopic and open minor hepatic resections and share the experience. Material and methods From 2011 to 2015, ten patients underwent robotic and 19 patients under...

Hintergrund: Der Vorteil minimalinvasiver Operationen an der Leber bei selektierten Patienten ist belegt. Der Roboter bietet technische Innovationen, die zukünftig die minimalinvasive Leberchirurgie verändern werden. Wir präsentieren erste Erfahrungen mit dieser Methode in unserem Patientenkollektiv. Material und Methoden: Bei 14 Patienten mit beni...

BACKGROUND: The advantages of minimally invasive liver resections for selected patients are evident. Robots provide new innovations that will influence minimally invasive liver surgery in the future. This article presents our initial experience with this technology in our patient population. Material und Methods: In 14 patients with benign or malig...

Introduction: The aim of the study was to assess the diagnostic accuracy of procalcitonin (PCT) as a marker for complications and as a prognostic factor for mortality after liver transplantation. Material and methods: Liver transplant patients between January 2007 and April 2011 were prospectively included in the study. Procalcitonin serum conce...

The surgical resection of metastases is nowadays feasible in selected patients with multifocal metastatic disease due to the implementation of interdisciplinary multimodal therapeutic options. Anatomical limitations do not seem to represent obstacles which cannot be overcome because of the development of new surgical techniques. The cornerstone of...

The malposition of gallbladder under the liver segment III, defined as left-sided gallbladder (LSG), is an unexpected situation for the laparoscopic surgeon. The purpose of this study is to present our experience in treating patients with cholecystitis and LSG discovered incidentally during laparoscopic surgical procedure. Between 1993 and 2009, 55...

Background: Minimally invasive liver surgery is growing worldwide with obvious benefits for the treated patients. These procedures maybe improved by robotic techniques, which add several innovative features. In Germany, we were the first surgical department implementing robotic assisted minimally invasive liver resections. Material and methods:...

Background-Aim The vast majority of bile duct injuries occur in cases of open or laparoscopic cholecystectomy. Numerous reports have demonstrated that the incidence of iatrogenic bile duct injuries (IBDI) has risen from 0.3% to 0.6% since the introduction of laparoscopic cholecystectomy. There are many classifications of iatrogenic bile duct injuri...

Purpose: Complete mesocolic excision (CME) is nowadays state of the art in the treatment of colon cancer. In cases of carcinoma of transverse colon and of both flexures an extramesocolic lymph node metastasis can be found in the infrapancreatic lymph node region (ILR) and across the gastroepiploic arcade (GLR). These direct metastatic routes were...

A number of studies have demonstrated that lymph node metastasis is a poor prognostic factor in colon cancer. Advances of surgical procedure have improved the outcomes of colon cancer treatment. The aim of this study was to compare the characteristics of surgery for stage III colon cancer between England, Germany, and Japan. Using the data of patie...

Hepatocellular carcinoma (HCC) is among the most frequent malignant diseases worldwide. In the vast majority of cases, it is associated with liver cirrhosis. Liver transplantation (OLT) is potentially the gold standard treatment for patients suffering HCC in cirrhosis, because of synchronous eradication of HCC and of the underlying hepatic disease....

Acute cellular and chronic graft rejection are major disorders in the postoperative setting after orthotopic liver transplantation (OLT). An immediate diagnosis and successful therapy are essential for graft survival. We sought to determine whether quantitative and qualitative analysis of Doppler sonography data was predictive and sensitive as noni...

Introduction: Because of the potential benefit of robotics in pancreatic surgery, we review our experience at two minimally invasive pancreatic surgery centers that utilize a robotically controlled laparoscope holder to see if smaller robots that enable the operating surgeon to maintain contact with the patient may have a role in the treatment of...

Background: Elective surgery for liver hemangioma is controversial. We reviewed long-term outcomes following elective hepatectomy or observation only for symptomatic and asymptomatic liver hemangioma. Methods: All patients (n = 307) with liver hemangioma referred to our hospital for surgical evaluation from January 1988 to December 2009 were ide...

Background: Hiatus hernias are considered as the most prominent form of diaphragmatic hernias. The passage is defined through the oesophageal hiatus, resulting in a superdiaphragmatic displacement of parts of the stomach or the complete stomach, respectively. In our work we investigated the treatment of partial thoracic stomach with both open and...

In 29 patients the peak-PCT occurred within 48 hours after OLT. A rapidly rising PCT was observed in 2 patients associated with subsequent fatal outcomes. Among the 10 patients with peak-PCT values less than 5 ng/mL, 9 displayed uneventful postoperative courses. PCT values more than 5 ng/mL were observed among 22 patients with 23 OLT, including 12...

Tumor cell dissemination from the primary tumor site to distant organs is one of the characteristic properties of malignant tumors and represents a crucial step in the progression of disease. Although the pattern of spread may vary in different types of carcinomas, dissemination via the lymphatic system represents a common event in metastasis. The...

Background: The necessity for radical lymph node dissection for solid tumours was discussed in the past controversially. The aim of this study was to correlate the oncologic results of radical surgery for colon cancer with potential complications. Methods: A total of 1,453 patients with R0-resected colon cancer operated on between 1978 and 2004...

Introduction Although many are reluctant to embrace minimally invasive pancreaticoduo-denectomies (MIPDs) until large prospective scientific trials are performed; pancreatic surgeons with advanced minimally invasive techniques have shown that MIPD is feasible, and that it can be performed safely with comparable outcomes to open procedures for both...

Background: Integrated operation systems were developed for centralization and easy control of all components within the operating room (OR). These systems represent central units that use communication technology to connect and control various components of the OR. Voice control that is independent of the speaker has been a pioneering innovation...

Cytomegalovirus (CMV) infections are among the most common infections following liver transplantation. The main preventive methods for CMV infections are universal prophylaxis and pre-emptive therapy. In our study, we adopted a pre-emptive strategy in a higth-risk group of donor CMV-positive (D+)/recipient CMV-negative (R-) casses. We investigated...

Spigelian Hernia (SH) is a rare ventral hernia with a high incarceration and obstruction risk. The purpose of this study is to present our experience in diagnosis and treatment of this rare hernia entity. Sixteen patients underwent surgery for SH between 2000 and 2010. Analysis parameters included demographic data, location of defect, diagnostic me...

Over recent years, patient outcomes after colon cancer resection have not improved to the same degree as for rectal cancer. Japanese D3 resection and European complete mesocolic excision (CME) with central vascular ligation (CVL) are both based on sound oncologic principles. Expert surgeons using both techniques report impressive outcomes as compar...

In general, hepatic metastasis from stomach carcinoma has an unfavorable prognosis. In addition, there are often further metastases in other organs, such as peritoneal carcinomatosis. The major aim of the present study was to investigate a potential curative surgical approach in these patients. Thirty-one patients with hepatic metastases from stoma...

The management of hepatocellular adenoma (HA) is dependent on several parameters, which are influencing the decision for further management. The aim of this study was to evaluate the clinical presentation, indications, and long-term outcome of surgical treatment in a single-institution analysis. Forty-nine patients underwent elective hepatectomy fo...

BACKGROUND: Hepatocellular carcinoma (HCC) with complete obstruction of the bile duct or with infiltration of the colon is very rare. The treatment strategy for patients with an advanced HCC is not clearly defined. METHODS: We present a unique case of HCC with synchronous tumor thrombosis of the bile duct and the right branch of the portal vein and...

Compliance problems have arisen due to the twice a day administration of calcineurin inhibitors (CNI). We examined the safety, indications, and efficacy in terms of graft and patient survivals after conversion from tacrolimus to sirolimus or advagraf. Between January 2006 and December 2009, 36 orthotopic liver transplantation patients underwent con...

Recurrent hepatitis C infection in the posttransplant setting is a serious problem. The aim of this study was to evaluate the efficacy, safety, indications, optimal time of administration and adequate duration of antiviral therapy with pegylated interferon alpha 2 b (PEG-IFN) and ribavirin (RIB). Between 2003 and 2009, 16 patients received antivira...

The prediction of outcome in pancreatic neuroendocrine tumors (P-NETs) still represents a challenge. Several clinicopathologic parameters have been proposed to predict adverse outcome. The aim of this study was to evaluate the impact of tumor necrosis and angioinvasion on the outcome after curative R0 resection of P-NETs. We reviewed our institutio...

Postoperative biliary tract complications after liver transplantation (LT) still lead to early and late morbidity and mortality. Modern interventional endoscopic techniques can replace surgical repair as the first line of treatment. Nevertheless surgical intervention plays an important role in specific situations. We performed a retrospective analy...

Background: Orthotopic liver transplantation (OLT) is a treatment for end-stage liver disease. The shortage of available organs leads to the acceptance of marginal grafts, thereby increasing the risk of perioperative complications such as acute rejection, infection, and graft dysfunction Procalcitonin (PCT) has been shown to be a reliable marker f...