Background/Aims: To analysis the appendiceal mucinous lesions according to the World Health Organization (WHO) 2010 and 2019 classification of tumors of the digestive system (non-neuroendocrine tumors of the appendix vermiformis) Materials and Methods: Clinical and histopathological data of 37 patients with histopathologically proven appendiceal mucinous lesion from January 2010 to May 2019 were evaluated retrospectively. Pathology slides were re-evaluated by two pathologists according to the WHO 2010 and WHO 2019 classification of tumors of the digestive system. Results: Totally 37 patients (male:19 female: 18) aged 23 to 93 years were analyzed. Majority of the patients (75.7 %) had underwent appendectomy due to preliminary diagnosis of acute appendicitis (n=22) or periappendiceal tumoral lesions (n=9), the others (n=9) underwent incidental appendectomy. Whereas acute appendicitis was histopathologically diagnosed in 16 (43.2%) patients, perforation was diagnosed in 12 (32.4%) patients (perforation without appendicitis=3, perforation with appendicitis=6). According to WHO 2010 classification, pathology reports were prepared as follows: mucocele (n=10), mucinous cystadenoma (n=9), low-grade mucinous neoplasm (n=6), mucinous adenocarcinoma (n=5), mucosal hyperplasia + mucocele (n=3), mucosal hyperplasia (n=2), hyperplastic polyp (n=1), adenomatous polyp (n=1). On the basis of the WHO 2019 classification, pathology reports were prepared as follows: low-grade mucinous neoplasm (n=17), simple retention cysts (n=6), hyperplastic polyp (n=6), mucinous adenocarcinoma (n=5), ruptured appendiceal diverticula (n=2), sessile serrated lesion (n=1). Conclusion: The term of appendiceal mucinous lesion, which is recently introduced into medical literature is suitable to distinguish between lesions with and without malignancy potential. The WHO 2019 classification system has been an important step in simplifying the classification of non- neuroendocrine tumors of the appendix vermiformis.

Background: To present the struggle of a high volume liver transplant center against coronavirus infectious disease-2019 pandemic. Methods: Between March 2020 and December 2020, the demographic and clinical data of staff and liver transplant candidates diagnosed with coronavirus infectious disease-2019 in our Liver Transplant Institute were prospectively analyzed. Results: First, 32 healthcare staff were diagnosed with coronavirus infectious disease-2019, and 6 of them were surgeons. Six staff were asymptomatic, while 24 staff had mild or moderate and 2 staff had severe coronavirus infectious disease-2019. All the staff recovered from the disease without any permanent sequela and returned to duty after 2 consecutive negative polymerase chain reaction results within 24-hour intervals. Second, during the preoperative investigation, 6 living liver donor candidates and 13 recipients were tested positive for coronavirus infectious disease-2019 (son = 6, unrelated = 3, cousin = 3, daughter = 2, cadaveric = 1). Eleven patients received favipiravir and 8 did not receive any treatment because they were asymptomatic. Only one recipient who had severe coronavirus infectious disease-2019 died due to multiple organ failure syndrome. One recipient died in the early postoperative period. The median duration from the initial diagnosis of the patients till the transplant procedure was 21 days (min-max: 14-105 days). During the time of operation, the polymerase chain reaction tests of the donors and the recipients were negative, and the thorax tomography images showed no signs of viral pneumonia. Conclusion: Meticulous precautions, multidisciplinary approach, team effort, and organization of facilities can increase the quality of care of these patients in the coronavirus infectious disease-2019 era. Healthcare workers have shown tremendous effort and are the true heroes of this era. Cite this article as: Başkıran A, Akbulut S, Şahin TT, et al. Coronavirus precautions: Experience of high volume liver transplant institute. Turk J Gastroenterol. 2022;33(2):145-152.

Background: In liver transplant (LT) recipients, immunosuppressive therapy may potentially increase the risk of severe COVID-19 and may increase the mortality in patients. However, studies have shown conflicting results, with various studies reporting poor outcomes while the others show no difference between the LT recipients and healthy population. The aim of this study is to determine the impact of the COVID-19 pandemic on survival of LT recipients. Methods: This is a retrospective cohort study analyzing the data from 387 LT recipients diagnosed with COVID-19. LT recipients were divided into two groups: survival (n = 359) and non-survival (n = 28) groups. A logistic regression model was used to determine the independent risk factors for mortality. Machine learning models were used to analyze the contribution of independent variables to the mortality in LT recipients. Results: The COVID-19-related mortality rate in LT recipients was 7.2%. Multivariate analysis showed that everolimus use (p = 0.012; OR = 6.2), need for intubation (p = 0.001; OR = 38.4) and discontinuation of immunosuppressive therapy (p = 0.047; OR = 7.3) were independent risk factors for mortality. Furthermore, COVID-19 vaccination reduced the risk of mortality by 100 fold and was the single independent factor determining the survival of the LT recipients. Conclusion: The effect of COVID-19 infection on LT recipients is slightly different from the effect of the disease on the general population. The COVID-19-related mortality is lower than the general population and vaccination for COVID-19 significantly reduces the risk of mortality.

Background: Examinations of procalcitonin (PCT) and Ki-67 expression levels in hepatocellular carcinoma (HCC) patients who have undergone liver transplantation (LT) through immunohistochemical analyses of tumor tissue may reveal the biological characteristics of the tumor, thus informing the selection of HCC patients for LT. Methods: Hepatectomy specimens from 86 HCC patients who underwent LT were obtained and analyzed immunohistochemically for the expression of PCT and Ki-67. The percentage and intensity of PCT staining, as well as the percentage of Ki-67 expression, were assessed for each patient. The impacts of PCT and Ki-67 expression on disease-free survival, overall survival, and the recurrence rate were studied, as well as their correlations with other clinicopathological features. Results: The recurrent HCC group showed a higher Ki-67 level (p < 0.001), larger maximum dominant tumor diameter (p < 0.001), and higher rate of vascular invasion (p = 0.001). The pre-transplant AFP (p = 0.001), maximum dominant tumor diameter (p < 0.001), number of tumor nodules (p < 0.001), rate of vascular invasion (p = 0.001), and Ki-67 level (p = 0.044) were higher in patients beyond the Milan criteria. Similarly, the pre-transplant AFP (p < 0.001); maximum dominant tumor diameter (p < 0.001); number of tumor nodules (p < 0.001); rates of portal vein tumor thrombus (p = 0.002), poor differentiation (p = 0.021), and vascular invasion (p < 0.001); and Ki-67 level (p = 0.010) were higher in patients beyond the expanded Malatya criteria. The maximum dominant tumor diameter (p = 0.006); Ki-67 level (p = 0.003); rates of vascular invasion (p < 0.001), cases beyond the Milan criteria (p = 0.042) and the expanded Malatya criteria (p = 0.027), and portal vein tumor thrombus (p = 0.020); and presence of recurrence (p < 0.001) were higher in HCC patients with mortality. The Kaplan–Meier estimates indicated that Ki-67 levels exceeding 5% significantly affected DFS and OS. Although the Kaplan–Meier estimates indicated that a PCT staining percentage of ≥25% did not have a statistically significant effect on DFS or OS, the outcomes may be considered clinically significant. Conclusions: This study demonstrated that the Ki-67 proliferation index can be used as a predictive biomarker of the biological behavior of HCC. Furthermore, we claim that PCT expression over a particular threshold might impact recurrence and survival, and we believe that further multicenter prospective studies focused on standardized PCT antibody staining are crucial in order to determine its potential as a biomarker for HCC.

Background: Inflammation and the associated immune pathways are among the most important factors in liver regeneration after living donor hepatectomy. Various biomarkers, especially liver function tests, are used to show liver regeneration. The aim of this study was to evaluate the course of liver regeneration following donor hepatectomy (LDH) by routine and regeneration-related biomarkers. Method: Data from 63 living liver donors (LLDs) who underwent LDH in Inonu University Liver Transplant Institute were prospectively analyzed. Serum samples were obtained on the preoperative day and postoperative days (POD) 1, 3, 5, 10, and 21. Regenerative markers including alfa-fetoprotein (AFP), des carboxy prothrombin (DCP), ornithine decarboxylase (ODC), retinol-binding protein 4 (RBP4), and angiotensin-converting enzyme isotype II (ACEII) and liver function tests including alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP) and total bilirubin levels were all analyzed. Results: The median age of the LLDs was 29.7 years and 28 LLDs were female. Eight LLDs developed postoperative complications requiring relaparotomy. The routine laboratory parameters including AST (<0.001), ALT (<0.001), ALP (<0.001), and total bilirubin (<0.001) showed a significant increase over time until postoperative day (POD) 3. For the regeneration-related parameters, except for the RBP4, all parameters including ACEII (p = 0.006), AFP (p = 0.002), DCP (p = 0.007), and ODC (p = 0.002) showed a significant increase in POD3. The regeneration parameters showed a different pattern of change. In right-lobe liver grafts, ACEII (p = 0.002), AFP (p = 0.035), and ODC (p = 0.001) showed a significant increase over time. DCP (p = 0.129) and RBP4 (p = 0.335) showed no significant changes in right-lobe liver grafts. Conclusions: Regenerative markers are increased in a sustained fashion following LDH. This is more prominent following right-lobe grafts which are indicative of progenitor-associated liver regeneration.