Safak Gül-Klein

Dr. Safak Gül-Klein

Chirurgische Klinik, Campus Charité Mitte und Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
12 August 2021 in Medicina
Verified
Journal Article
Open access
PDF file
SMSimon Moosburner
Simon Moosburner
MSMoritz Schmelzle
Moritz Schmelzle
WSWenzel Schöning
Wenzel Schöning
AKAnika Kästner
Anika Kästner
PSPhilippa Seika
Philippa Seika
SGSafak Gül-Klein
Safak Gül-Klein
Background and Objectives: In children, hepatoblastoma preferentially is managed by liver resection (LR). However, in irresectable cases, liver transplantation (LT) is required. The aim of our study was to compare short- and long-term results after LR and LT for the curative treatment of hepatoblastoma. Materials and Methods: Retrospective analysis of all patients treated surgically for hepatoblastoma from January 2000 until December 2019 was performed. Demographic and clinical data were collected before and after surgery. The primary endpoints were disease free survival and patient survival. Results: In total, 38 patients were included into our analysis (n = 28 for LR, n = 10 for LT) with a median follow-up of 5 years. 36 patients received chemotherapy prior to surgery. Total hospital stay and intensive care unit (ICU) stay were significantly longer within the LT vs. the LR group (ICU 23 vs. 4 days, hospital stay 34 vs. 16 days, respectively; p < 0.001). Surgical complications (≤Clavien–Dindo 3a) were equally distributed in both groups (60% vs. 57%; p = 1.00). Severe complications (≥Clavien–Dindo 3a) were more frequent after LT (50% vs. 21.4%; p = 0.11). Recurrence rates were 10.7% for LR and 0% for LT at 5 years after resection or transplantation (p = 0.94). Overall, 5-year survival was 90% for LT and 96% for LR (p = 0.44). Conclusions: In irresectable cases, liver transplantation reveals excellent outcomes in children with hepatoblastoma with an acceptable number of perioperative complications.

14 February 2021 in Nutrients
Verified
Journal Article
Open access
PDF file
SGSafak Gül-Klein
Safak Gül-Klein
DHDeana Haxhiraj
Deana Haxhiraj
JSJulian Seelig
Julian Seelig
AKAnika Kästner
Anika Kästner
JHJulian Hackler
Julian Hackler
Lutz SchomburgLutz Schomburg
Lutz Schomburg
The trace element selenium (Se) is taken up from the diet and is metabolized mainly by hepatocytes. Selenoprotein P (SELENOP) constitutes the liver-derived Se transporter. Biosynthesis of extracellular glutathione peroxidase (GPx3) in kidney depends on SELENOP-mediated Se supply. We hypothesized that peri-operative Se status may serve as a useful prognostic marker for the outcome in patients undergoing liver transplantation due to hepatocellular carcinoma. Serum samples from liver cancer patients were routinely collected before and after transplantation. Concentrations of serum SELENOP and total Se as well as GPx3 activity were determined by standardized tests and related to survival, etiology of cirrhosis/carcinoma, preoperative neutrophiles, lymphocytes, thyrotropin (TSH) and Child–Pugh and Model for End-Stage Liver Disease (MELD) scores. A total of 221 serum samples from 79 transplanted patients were available for analysis. The Se and SELENOP concentrations were on average below the reference ranges of healthy subjects. Patients with ethanol toxicity-dependent etiology showed particularly low SELENOP and Se concentrations and GPx3 activity. Longitudinal analysis indicated declining Se concentrations in non-survivors. We conclude that severe liver disease necessitating organ replacement is characterized by a pronounced Se deficit before, during and after transplantation. A recovering Se status after surgery is associated with positive prognosis, and an adjuvant Se supplementation may, thus, support convalescence.

6 April 2019 in Colorectal Disease
Verified
Journal Article
Closed access
PDF file
SGSafak Gül-Klein
Safak Gül-Klein
Matthias BieblMatthias Biebl
Matthias Biebl
BKBelinda Knoll
Belinda Knoll
LDLuca Dittrich
Luca Dittrich
SWSascha Weiß
Sascha Weiß
FAFelix Aigner
Felix Aigner

31 March 2021 in Cancers
Verified
Journal Article
Open access
PDF file
Ramin Raul Ossami SaidyRamin Raul Ossami Saidy
Ramin Raul Ossami Saidy
MPMaximilian Paul Postel
Maximilian Paul Postel
MPMichael Pflüger
Michael Pflüger
WSWenzel Schöning
Wenzel Schöning
Robert ÖllingerRobert Öllinger
Robert Öllinger
Dennis EurichDennis Eurich
Dennis Eurich
Introduction: Recurrence of hepatocellular carcinoma (rHCC) after liver transplantation (LT) is associated with limited survival. Therefore, identification of factors that prolong survival in these patients is of great interest. Surgical resection, radiotherapy, and transarterial chemoembolization (TACE) are established interventions to improve outcomes in these patients; however, the impact of immunosuppression is unknown. Methods: All patients diagnosed with rHCC in the follow-up after LT were identified from a database of liver recipients transplanted between 1988 and 2019 at our institution (Charité Universitätsmedizin Berlin, Germany). Based on the immunosuppressive regimen following diagnosis of rHCC and the oncological treatment approach, survival analysis was performed. Results: Among 484 patients transplanted for HCC, 112 (23.1%) developed rHCC in the follow-up. Recurrent HCC was diagnosed at a median interval of 16.0 months (range 1.0–203.0), with the majority presenting early after transplantation (63.0%, <2 years). Median survival after rHCC diagnosis was 10.6 months (0.3–228.7). Reduction of immunosuppression was associated with improved survival, particularly in patients with palliative treatment (8.4 versus 3.0 months). In addition, greater reduction of immunosuppression seemed to be associated with greater prolongation of survival. Graft rejection after reduction was uncommon (n = 7, 6.8%) and did not result in any graft loss. Patients that underwent surgical resection showed improved survival rates (median 19.5 vs. 8.7 months). Conclusion: Reduction of immunosuppressive therapy after rHCC diagnosis is associated with prolonged survival in LT patients. Therefore, reduction of immunosuppression should be an early intervention following diagnosis. In addition, surgical resection should be attempted, if technically feasible and oncologically meaningful.

1 March 2021 in Journal of Hepatocellular Carcinoma
Verified
Journal Article
Open access
PDF file
SGSafak Gül-Klein
Safak Gül-Klein
AKAnika Kästner
Anika Kästner
PHPhilipp Konstantin Haber
Philipp Konstantin Haber
FKFelix Krenzien
Felix Krenzien
SWSimon Wabitsch
Simon Wabitsch
MSMoritz Schmelzle
Moritz Schmelzle
Purpose: The impact of acute rejection (AR) after liver transplantation (LT) for hepatocellular carcinoma (HCC) on patient outcome is uncertain. This aim of this study is to investigate whether AR is associated with HCC relapse and overall survival. Patients and Methods: Patients undergoing LT for HCC between 2001 and 2015 were retrospectively analyzed with regard to histopathological proven AR within the median time until recurrence. Cox’s regression analysis was conducted revealing risk factors for HCC recurrence. Results: HCC recurred in 47 of 252 analyzed patients with a median time to recurrence of 20 months. Patients with AR (28.6%) had a significantly higher frequency of recurrence compared to patients without AR (13.0%, p=0.002). Multiple Cox regression analyses identified AR within 20 months to be an independent risk factor for HCC recurrence both as dichotomized (HR=2.91, 95%CI: 1.30– 6.53; p=0.009) and as a continuous variable (HR=1.81, 95%CI: 1.28– 2.54; p=0.001). HCC recurrence and AR were associated with higher grades of liver fibrosis one year after LT, when compared to patients without AR (p=0.019). Conclusion: Our results demonstrate an association of AR with HCC recurrence after LT with implications for intervals of monitoring in tumor surveillance. Graft fibrosis and immune mechanisms are potentially related and causal interactions are worth further investigation.

12 March 2020 in Pediatric Transplantation
Verified
Journal Article
Open access
PDF file
SGSafak Gül-Klein
Safak Gül-Klein
TDTomasz Dziodzio
Tomasz Dziodzio
FMFriederike Martin
Friederike Martin
AKAnika Kästner
Anika Kästner
CWChristian Witzel
Christian Witzel
RÖRobert Öllinger
Robert Öllinger
Abdominal wall closure after pediatric liver transplantation (pLT) in infants may be hampered by graft‐to‐recipient size discrepancy. Herein, we describe the use of a porcine dermal collagen acellular graft (PDCG) as a biological mesh (BM) for abdominal wall closure in pLT recipients. Patients <2 years of age, who underwent pLT from 2011 to 2014, were analyzed, divided into definite abdominal wall closure with and without implantation of a BM. Primary end‐point was the occurrence of postoperative abdominal wall infection. Secondary end‐points included 1‐ and 5‐year patient and graft survival and the development of abdominal wall hernia. In five out of 21 pLT recipients (23.8%), direct abdominal wall closure was achieved, whereas 16 recipients (76.2%) received a BM. BM removal was necessary in one patient (6.3%) due to abdominal wall infection, whereas no abdominal wall infection occurred in the no‐BM group. No significant differences between the two groups were observed for 1‐ and 5‐year patient and graft survival. Two late abdominal wall hernias were observed in the BM group vs none in the no‐BM group. Definite abdominal wall closure with a BM after pLT is feasible and safe when direct closure cannot be achieved with comparable postoperative patient and graft survival rates.