Annals of Gastroenterological Surgery最新文献

We gratefully acknowledge Drs. Daungsupawong and Wiwanitkit's insights regarding our recently published article “Antibody titer after administration of mRNA-based vaccine against severe acute respiratory syndrome coronavirus 2 in liver transplant recipients.”¹ We reported that mRNA vaccines induce similar humoral responses and decay rates of acquired antibodies in liver-transplant recipients as in healthy individuals.² Accordingly, we deduced that liver-transplant recipients should receive booster vaccination. Although we agree with the majority of the authors' points, we would like to address some of their concerns that were expressed in their Letter to the Editor.

In Japan, as the local government has provided free vaccination against the coronavirus disease (COVID-19), liver-transplant recipients have good access to healthcare. Adults were eligible for vaccination throughout, and children could receive vaccination midway through, the study period. Based on the study's results, liver-transplant recipients received regular vaccinations, and continued to receive booster vaccinations (given every 6 months after the second vaccination) even after the study ended. The average observation period for target patients after the second vaccination was 328 ± 64 days in the study.

With regard to the pre-vaccination history of infections, the impact was likely small, as only two recipients tested positive for anti-nucleocapsid antibodies at the first measurement. Although, data on current infection rates are unavailable, no recipient has developed severe pneumonia in the 1 year since study completion. In the statistics reported by the Japan Society for Transplantation on COVID-19 cases up to August 31, 2022,³ only 237 recipients, including those from our facility, were infected, which is a relatively low incidence. This is largely attributable to nonpharmaceutical preventive interventions, including the behavioral changes of liver-transplant recipients who refrained from venturing out during the COVID-19 pandemic. The infection rate could increase henceforth.

To investigate the protection conferred by neutralizing antibodies against infection, the antibody titer needs frequent measurement to determine the level necessary to prevent infection. However, this is not feasible in clinical practice. As COVID-19 is not a seasonal illness, perennial prevention is essential. Considering the decay rate of neutralizing antibodies, annual booster vaccination seems insufficient to provide preventive immunity. However, with the increased number of individuals with a history of COVID-19 in the community currently, the risk of cluster outbreaks has decreased. Therefore, with regard to vaccination, a multi-societal perspective, which includes infection severity, is needed. As there is an uncertain trend in SARS-CoV-2 infection rates in liver-transplant recipients, continuing booster

Retroperitoneal sarcoma (RPS) is a rare tumor classified into many histological types. It is also often detected only after it has grown to a considerable size and requires extensive resection of the surrounding organs, making it difficult to offer optimal patient-tailored management. Evidence supporting specific treatment modalities for RPS is insufficient, owing to its rarity. The Japanese clinical practice guidelines for RPS were published in December 2021, with the aim of accumulating existing evidence and indicating the optimal practice for RPS. These guidelines provide important clinical questions (CQs) concerning the diagnosis and treatment of RPS. This review, with a particular focus on primary RPS, attempts to introduce clinical problems in the diagnosis and treatment of RPS and to assess those problems along with the CQs in the guidelines. According to these guidelines, although chemotherapy and radiotherapy are expected to have therapeutic effects, the level of evidence to support these treatments is not very high at present. Accordingly, complete resection of the tumor is the first and only option for managing primary RPS. However, as with other tumors, the demand for multidisciplinary treatment for RPS is increasing. These guidelines will undoubtedly represent a milestone in clinical practice in relation to RPS in the future, and further evidence is expected to be accumulated based on the CQs that have been proposed.