It is established that administration of the COVID-19 vaccine may be associated with an exaggerated immune response leading to enlargement of several lymph nodes. Although most cases are benign and self-limiting, some have been reported in the literature as B-cell or T-cell lymphomas, with no reported cases of chronic lymphocytic leukaemia (CLL). We report two cases of follicular lymphoma and CLL that occurred a few weeks after COVID-19 vaccination. Case 1 is a 48-year-old woman who noticed two significantly palpable masses, one in each axilla, 48 h after receiving the first dose of the Pfizer-BioNTech BNT162b2 vaccine for COVID-19. Seven days later, she noticed another mass on the right side of her neck, which was biopsied within 48 hours. Case 2 is a 75-year-old man who presented with localized swellings in the axilla and on the neck, noted 24 h after the first dose of the Moderna messenger RNA-1273 COVID-19 vaccine. Neither patient reported any constitutional or associated symptoms. Surgical biopsy of the axillary lymph node in case 1 revealed a non-Hodgkin lymphoma, confirmed via immunohistochemistry as CD20-positive B-cell follicular lymphoma. The patient also had multiple pre- and para-aortic lymph nodes. In case 2, complete blood count showed lymphocytosis (total white blood cell – 148 × 109/L; lymphocyte differential – 92%), while peripheral blood film showed lymphocytosis with a predominance of small, mature-looking lymphocytes, both suggesting CLL. Although requested, immunophenotyping and molecular testing were not performed due to patient-related challenges. Although a chance occurrence is possible, lymphoid malignancies should be considered a strong differential. The vaccination history of patients presenting with clinical manifestations suggestive of a lymphoid malignancy should be thoroughly investigated, while ruling out other possible differentials such as a benign, self-limiting inflammatory process.

The gut microbiota is crucial in maintaining host health and liver function. Fecal microbiota transplantation (FMT) has shown promising potential in treating chronic liver diseases. To help clinicians quickly master and standardize the clinical application of FMT for chronic liver disease, the Liver Related Digestive Diseases Group of the Chinese Society of Hepatology of the Chinese Medical Association has developed the “Expert Consensus on the Clinical Application of FMT for Chronic Liver Disease.” This consensus addresses the key aspects of FMT, including the indications, contraindications, efficacy, safety, donor selection, transplantation routes, precautions, and the prevention and management of adverse reactions for chronic liver conditions, such as chronic hepatitis, cirrhosis, and liver cancer, thereby offering reference and guidance to clinicians implementing FMT in the treatment of chronic liver disease.

Antralization is considered a critical, reversible stage preceding gastric cancer. However, available biomarkers for identifying antralization are lacking. This study aimed to explore antralization-specific biomarkers in peripheral blood and gastric mucosa.

In this prospective cohort study, adult patients presenting with upper gastrointestinal symptoms were enrolled and categorized into antralization and non-antralization groups based on pathological examination of gastric mucosa. Helicobacter pylori (H. pylori) infection was detected using the 13C-urea breath test, rapid urease test, and/or H. pylori serological test. Blood samples and gastric biopsies were collected for biomarker analysis.

Of the 92 patients studied, 42 (45.7%) were diagnosed with H. pylori infection and 61 (66.3%) with antralization. The rate of H. pylori infection and the incidence of acid reflux were higher in the antralization group than in the non-antralization group (both P < 0.05). Patients with antralization had higher plasma lymphocyte counts and lower serum levels of lipopolysaccharide (both P < 0.05). The positive rates and intensity of trefoil factor-2 and mucin (MUC) 6 expression were higher, whereas the positive rate and intensity of MUC5AC expression were lower in the incisura and body mucosa with antralization compared with those without antralization (all P < 0.05). Additionally, the intensity of MUC5B expression was higher in the gastric body mucosa with antralization than in those without antralization (P < 0.05).

Increased lymphocyte counts and decreased lipopolysaccharide levels in the blood, along with increased expression of trefoil factor-2, MUC6, and MUC5B and decreased MUC5AC expression in the proximal gastric mucosa, appear to be antralization-specific.

Medulloblastoma (MB) is a malignant neoplasm that is relatively common in children but rare in young adults, accounting for less than 1% of all intracranial tumors. This study reports a rare case of MB metastasis to the right temporoparietal region in a 42-year-old woman, presenting with focal neurological symptoms such as weakness in the left arm and leg, speech disturbances, and impaired coordination. The patient had a history of cerebellar MB and underwent surgical resection, radiation therapy, and chemotherapy. Despite treatment, metastasis occurred, highlighting the diagnostic and therapeutic challenges in adult MB cases. The article also reviews the literature on MB in young adults, emphasizing the importance of dynamic neuroclinical monitoring and timely instrumental diagnosis for early detection and management of MB metastases.

Hepatic metastasis (HM) and lymph node metastasis in pancreatic ductal adenocarcinoma (PDAC) are associated with worse overall survival, largely due to the immunosuppressive microenvironment. However, the key immunosuppressive cells within this microenvironment remain inadequately defined. This study aimed to identify the cells contributing to HM and lymph node metastasis in PDAC and to investigate their regulatory mechanisms.

Single-cell RNA sequencing was used to profile the tumor microenvironment in HM, lymph node-negative, and lymph node-positive (LNP) PDAC tissues. Bioinformatic analyses revealed subtypes of immunosuppressive myeloid-derived suppressor cells (MDSCs). Immunofluorescence and flow cytometry were performed to detect the distribution and proportion of interleukin-1 receptor antagonist (IL1RA+) MDSCs. The immunosuppressive and pro-tumorigenic functions of IL1RA+ MDSCs were analyzed using enzyme-linked immunosorbent assay, quantitative reverse transcription polymerase chain reaction, Western blotting, and Transwell assays. Patient-derived xenograft mouse models were employed to validate the role of IL1RA+ MDSCs in vivo.

Polymorphonuclear-MDSCs were found to be recruited to metastatic PDAC tissues. Among these, IL1RA+ MDSCs were enriched in HM/LNP tissues and correlated with poorer prognosis. IL1RA+ MDSCs promoted M2 macrophage polarization and suppressed the activity of natural killer cells and cytotoxic T cells. Furthermore, IL1RA+ MDSCs accelerated PDAC migration and progression by upregulating epithelial–mesenchymal transition-related proteins in both in vitro and in vivo models.

IL1RA+ MDSCs represent a key immunosuppressive and pro-tumorigenic subtype in HM/LNP PDAC, providing a solid theoretical basis for prognostic prediction and the development of immunotherapeutic strategies targeting these cells in HM/LNP PDAC.