Volume 106 · Issue 23 · 2026

The diagnosis of marginal zone lymphoma (MZL) still relies on morphology, immunohistochemistry, and flow cytometry. Pathologists and clinicians have some difficulties in the diagnosis and differential diagnosis of MZL. The key difficulty lies in its diverse clinicopathological manifestations and the lack of characteristic biomarkers or molecular biological features. Combined with clinical and pathological features, this article focuses on some difficulties in the related differential diagnosis, such as the differentiation between extranodal MZL (EMZL) of mucosa associated lymphoid tissues and reactive lesions, between spleen MZL (SMZL) and other splenic lymphomas, as well as MZL with plasmacytic differentiation from lymphoplasmacytic lymphoma (LPL) and myeloma, which aims to provide insights for both clinicians and pathologists in the differential diagnosis of MZL.

Marginal zone lymphoma (MZL) is a group of indolent B-cell lymphomas with high biological and clinical heterogeneity, including mucosa-associated lymphoid tissue, nodal, and splenic MZL. Despite diverse first-line treatment options, significant differences exist between guidelines and clinical practices, lacking a unified and standardized treatment pathway.Therefore, this article elaborates on the assessment of treatment indications of MZL, the initial therapies for different MZL subtypes, and summarizes the treatment for relapsed/refractory MZL, the selection of maintenance therapy, and management of treatment-related complications, aiming to offer evidence-based guidance and individualized therapeutic decision-making in clinical practice.

Marginal zone lymphoma (MZL) is characterized by high clinical heterogeneity, making individualized precision therapy highly contingent upon accurate staging and dynamic response assessment. This review systematically summarizes the current status and progress in the evaluation of splenic MZL (SMZL), mucosa-associated lymphoid tissue (MALT) lymphoma, and nodal MZL (NMZL). In terms of staging modalities, selection should be based on subtype-specific characteristics; notably, as a novel radiotracer, 68Ga-Pentixafor positron emission tomography/computed tomography (PET/CT) provides crucial complementary value for evaluating lesions with low ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) avidity. In terms of staging system, the modified Ann Arbor, Lugano classifications and MZL-specific designations (ⅠS, ⅡS) should be comprehensively applied. In terms of efficacy evaluation, the paradigm for response assessment is shifting from isolated morphological measurements toward a multidimensional model integrating functional imaging (Deauville score), molecular-level response monitoring [measurable residual disease (MRD) and circulating tumor DNA (ctDNA)], and patient-reported outcomes (PRO). Importantly, a sustained complete response at 24 months (CR24) has emerged as a critical surrogate endpoint for predicting long-term prognosis. Follow-up management necessitates risk stratification-based dynamic monitoring, with a focus on early warning of histological transformation. Ultimately, this review aims to provide a reference to further optimize the standardized clinical diagnosis, treatment and holistic management of MZL in China.

Marginal zone lymphoma (MZL) is an indolent B-cell non-Hodgkin lymphoma with marked heterogeneity. Currently, histological subtype, clinical stage, biochemical parameters, and clinical scoring systems represented by the MZL-international prognostic index (MZL-IPI) remain the principal basis for risk stratification; however, their differentiation power is limited, particularly for intermediate-risk groups, and they can not fully reflect the biological heterogeneity of the disease. Molecular genetic studies have revealed the significant prognostic impact of mutations in genes such as NOTCH2, KLF2, TNFAIP3, and TP53, as well as chromosomal abnormalities including t(11;18) and 7q deletion, with TP53 mutations being closely associated with histological transformation and high-risk outcomes. In the field of imaging, ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) has inherent limitations in MZL, whereas novel targeted tracers like C-X-C motif chemokine receptor type 4 (CXCR4) PET/CT show improved lesion detection rates and preliminary prognostic value, and imaging omics holds promise for non-invasively revealing tumor heterogeneity. This review systematically summarizes the current status and shortcomings of these prognostic factors, and proposes that future efforts should focus on integrating clinical, molecular genetics, imaging, and multi-omics data, and leveraging artificial intelligence technology to construct multicenter-validated, multidimensional prognostic models, so as to advance precision risk stratification and individualized treatment for MZL.

Sarcopenic obesity is a distinct subtype of obesity characterized by excessive adiposity combined with reduced skeletal muscle mass and impaired muscle function, which exerts dual and superimposed adverse impacts on human health. In accordance with the latest evidence-based medical evidence and clinical practical experience, the expert panel formulated the "Expert consensus on the clinical diagnosis and management of sarcopenic obesity (2026 edition)", aiming to provide standardized diagnosis and treatment regimens for clinicians. This consensus systematically elaborates on the definition, etiology, and epidemiological characteristics of sarcopenic obesity, the understanding of sarcopenic obesity in traditional Chinese medicine, diagnostic criteria, nutritional and exercise interventions, as well as the indications and safety of pharmacotherapy (including weight-loss medications and muscle-enhancing agents). Individualized management strategies are proposed for special populations, such as adolescents, the elderly, and menopausal individuals. Clinical decision-making and intervention intensity are recommended to be comprehensively evaluated by a multidisciplinary team, involving endocrinology, bariatric surgery, clinical nutrition, rehabilitation medicine, traditional Chinese medicine, general practice, and other related disciplines. Using the modified Delphi method as the core framework for consensus development, this consensus was established through systematic literature retrieval and refinement of key clinical issues to form a structured questionnaire. Consensus criteria were determined in accordance with international Delphi study protocols, and 9 recommendations were finally formulated. These recommendations systematically summarize nutritional intervention, exercise prescription, pharmacotherapy, and comprehensive management strategies for sarcopenic obesity, with the aim of promoting the standardization of clinical diagnosis and treatment of sarcopenic obesity in China.

Post-neurosurgical intracranial infection (PNII) is a common complication of neurosurgery, which is associated with poor outcomes. Key strategies to reduce infection rates and improve prognosis include strict perioperative infection control, early diagnosis of postoperative intracranial infections, and standardized comprehensive treatment. Based on previous guidelines and consensus, the Chinese Society of Neurosurgery, the Chinese Neurosurgery Intensive Care Management Collaboration Group, and the Beijing Neurosurgical Society convened a multidisciplinary team of experts in neurosurgery, infectious diseases, and clinical microbiology. This consensus was developed through systematic literature reviews and evidence-based medicine, integrating domestic and international epidemiological and clinical research evidence. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used for evidence evaluation and recommendation formulation. After multiple rounds of expert discussions and voting, 30 recommendations were finally established. This consensus covers the epidemiology of PNII, pathogen profiles, diagnostic criteria, perioperative prevention strategies, antimicrobial selection, multidrug-resistant organisms management, surgical interventions, and complication management. It aims to provide standardized guidance for clinical practice and to promote more standardized and refined management of PNII.

To investigate the effect of exogenous supplementation of umbilical cord blood (UCB) immune cells on immune function reconstruction and hematopoietic function recovery in elderly high-risk myeloid neoplasms (MN) patients.

The research includes clinical studies and cell experiments. Clinical data of elderly high-risk MN patients aged >60 years admitted to the Department of Hematology at the Second Hospital of Tianjin Medical University from January 2023 to June 2025 were retrospectively included. Based on treatment regimens, the patients were categorized into chemotherapy group ("3+7"regimen), demethylation therapy (HMA) group (decitabine-based therapy), and UCB group (venetoclax combined with azacitidine plus UCB reinfusion). At 28 days post-treatment, differences were compared among the groups regarding disease remission (complete remission rate), hematopoietic function reconstruction (recovery time of white blood cells and platelets), survival outcomes (overall survival rate and event-free survival rate), and cellular immune function reconstruction [levels of various CD4⁺T cells, CD8⁺T cells, natural killer (NK)cells, etc.]. To further confirm the role of UCB in the bone marrow microenvironment of MN patients, primary bone marrow cells were collected from 3 elderly high-risk MN patients in the UCB group (ileal bone marrow aspiration was performed on day 15 post-treatment and before UCB infusion, with 10 ml of bone marrow aspirated each time); additionally, UCB cells were obtained from 3 healthy donors (sourced from the Shandong Umbilical Cord Blood Hematopoietic Stem Cell Bank of China, all HLA 2/10 matched male donors). Based on different seeding methods of patient primary bone marrow cells and healthy donor UCB mononuclear cells in Transwell chambers, the cells were divided into a control group (patient bone marrow mononuclear cells cultured separately), an indirect co-culture group (non-contact co-culture of patient bone marrow mononuclear cells and UCB cells), and a direct co-culture group (contact co-culture of patient bone marrow mononuclear cells and UCB cells). After 48 hours of culture, the cells from the lower chamber and the supernatant were collected from each group. The proportional differences among immune cell subsets (various T-cell, B-cell, and NK cell subsets) were compared among the three groups, and the differences in cytokine levels among the three groups of the supernatants [tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-6] were also compared.

A total of 109 patients were enrolled, including 54 males and 55 females, with an age range [M (Q₁, Q₃)] of 68 (60, 87) years. There were 38, 39, and 32 cases in the chemotherapy group, HMA group, and UCB group, respectively. Analysis of disease response revealed that the complete response rates in the UCB group [43.8% (14/32) vs 28.2% (11/39), P<0.001] and the chemotherapy group [44.7% (17/38) vs 28.2% (11/39), P<0.001] were higher than those in the HMA group. In terms of hematopoietic function recovery, the median time to achieve target leukocyte counts in the UCB group was shorter than that in the chemotherapy group [22 (14, 28) vs 28 (24, 37) days, P<0.05] and the HMA group [22 (14, 28) vs 31 (21, 42) days, P<0.05]. Similarly, the median time to achieve target platelet counts in the UCB group was shorter than that in the chemotherapy group [24 (17, 29) vs 28 (23, 33) days, P<0.05] and the HMA group [24 (17, 29) vs 29 (22, 37) days, P<0.05]. The survival analysis demonstrated that the 3-year overall survival rate in the UCB group was higher than that in the HMA group (39.1% vs 19.7%, P<0.05), while no statistically significant difference was observed compared to the chemotherapy group (P>0.05). Similarly, the 3-year event-free survival rate in the UCB group was higher than that in the HMA group (35.8% vs 25.5%, P<0.05), with no statistically significant difference compared to the chemotherapy group (P>0.05). Regarding the reconstruction of cellular immune function, the proportion of CD4⁺central memory T cells in the UCB group at 28 days post-treatment was lower than that in the chemotherapy group [20% (9%, 29%) vs 32%(23%, 39%), P<0.05], while no statistically significant difference was observed compared to the HMA group (P>0.05). At 28 days post-treatment, the proportions of CD4⁺naive T cells [45% (30%, 58%) vs 22% (10%, 34%)] and CD8⁺naive T cells [41% (31%, 52%) vs 22% (8%, 36%)] in the UCB group were significantly higher than those in the HMA group (both P<0.05), while no statistically significant difference was observed compared to the chemotherapy group (both P>0.05). At 28 days post-treatment, the UCB group exhibited higher proportions of CD8⁺effector T cells [40% (33%, 50%) vs 18% (8%, 28%)], CD19⁺B cells [20% (13%, 27%) vs 12% (7%, 14%)], and NK cells [20% (15%, 26%) vs 14% (7%, 21%)] compared to the chemotherapy group (all P<0.05). However, the UCB group showed lower proportions of regulatory T cells at 28 days post-treatment than both the chemotherapy group [4% (4%, 6%) vs 7% (7%, 8%), P<0.05] and the HMA group [4% (4%, 6%) vs 8% (6%, 12%), P<0.05]. In terms of cellular experiments, differential analysis of immune cells revealed that the indirect co-culture group exhibited higher levels of CD8⁺naive T cells, CD4⁺naive T cells, NK cells, and CD19⁺B cell subsets compared to the control group; conversely, the levels of regulatory T cells and CD4⁺central memory T cells were lower than those in the control group (all P<0.05). Cytokine level analysis demonstrated that the direct co-culture group showed higher levels of TNF-α and IFN-γ, as well as lower levels of IL-6 compared to the control group (P<0.001).

Immunocytes such as NK cells in UCB may promote immune function reconstruction and hematopoietic recovery in patients, thereby improving their prognosis.

To analyze the characteristics of hospital associated infection (HAI) in children undergoing hematopoietic stem cell transplantation (HSCT).

The clinical data of children who underwent HSCT at Baoding Hospital, Beijing Children′s Hospital Affiliated to Capital Medical University and Beijing Children′s Hospital Affiliated to Capital Medical University between July 2021 and August 2024 were retrospectively collected. Based on the occurrence of HAI, the patients were divided into the infected group (children who developed at least one HAI during hospitalization) and the uninfected group (children who did not develop HAI during multiple hospitalizations). The characteristics of HAI in the two groups were analyzed.

A total of 651 patients were enrolled, including 138 patients (21.2%) in the infected group [93 males and 45 females; aged 8 (4, 12) years] and 513 patients in the uninfected group [328 males and 185 females; aged 7 (4, 11) years]. The infected group had 181 cases of HAI occurring during 150 hospitalizations among 138 pediatric patients. The incidence rate of HAI was 8.4% (episode incidence rate 10.1%), and the daily incidence rate of HAI was 3.3‰ (4.0‰). The mortality rate in the infected group was higher than that in the uninfected group [6.5% (9/138) vs 0.6% (3/513), P<0.001]. The top five HAI were gastrointestinal infections (41.4%), vascular catheter-related bloodstream infections (19.3%), bloodstream infections (non catheter-related, sepsis type, 12.2%), lower respiratory tract infections (8.3%), and upper respiratory tract infections (6.6%). A total of 179 pathogenic microorganisms were detected in 181 cases of HAI in the infected group. The proportion of viruses in gastric intestinal infection accounted for 76.0% (57/75). The proportion of bacteria in catheter-related bloodstream infections was 100.0% (35/35), while in septic-type bloodstream infections it accounted for 90.1% (20/22). Lower respiratory tract infections were caused by bacteria and viruses in equal proportions, each accounting for 29.4% (5/15). The proportion of viruses in upper respiratory tract infections accounts for 91.7% (11/12), and bacteria accounted for 68.2% (15/22) of other infections. The median hospitalization duration for HAI was 21 (11, 38) days, with statistically significant difference in the timing of infection occurrence across various infection sites (Z=20.09, P=0.001). A total of 117 cases (64.6%) of HAI were treated with antimicrobial agents, with a median duration of antimicrobial use of 7 (0, 18) days. There was a statistically significant difference in the duration of antibiotic use among different infection sites (Z=84.10, P<0.001).

The children with HAI have a higher mortality rate. Viral gastrointestinal infections are the most common type of HAI, followed by bacterial bloodstream infections; the timing of infection occurrence and the duration of antimicrobial use vary across different infection sites.

To analyze the clinical characteristics and disease spectrum trend of children in short stature outpatient clinic of Beijing Children′s Hospital, Capital Medical University in different years.

A retrospective analysis was performed on the medical records of children attending the short stature outpatient department of Beijing Children′s Hospital, Capital Medical University during the summer vacation (July 1 to September 30) in 2021, 2023 and 2025. Analyze the clinical characteristics and their distribution of children patients in 3 years. The Mantel-Haenszel trend χ² test was used to analyze the changing trends of various indicators and disease spectrum across the 3 years.

A total of 5 862 children were enrolled, including 3 022 boys and 2 840 girls, with the age of (9.6±3.2) years and the height of (131.7±20.4) cm. The age of children in the three years was (9.0±3.3), (9.6±3.1), and (10.1±2.9) years, respectively. No infants were admitted to the short stature outpatient clinic in any of the 3 years. The proportion of children in the toddler and preschool periods decreased year by year, while that in the school-age and adolescent periods increased gradually (all P_trend<0.001). The height of children in the 3 years was (123.4±23.9), (131.6±19.9), and (139.9±21.2) cm, respectively. The proportion of children with low height percentile (<P₃, P₃-<P₁₀) showed a decreasing trend, whereas the proportions of children with moderate to high height percentile (P₂₅-<P₅₀ to≥P₉₇) presented an increasing trend (all P_trend<0.05). The proportion of children with constitutional short stature decreased year by year, while the proportions of patients with adolescent short stature, slow or poor height growth, and precocious puberty increased annually (all P_trend<0.05).

During the summer periods of 2021, 2023 and 2025, among patients visiting the short stature outpatient clinic of Beijing Children′s Hospital, Capital Medical University, the proportions of school-age and adolescent children, children with height at≥P₂₅ percentile, and cases of precocious puberty all increased year by year.

To explore the value of different plasma endotoxin levels in evaluating early prognosis of patients with sepsis.

A total of 150 sepsis patients confirmed by plasma endotoxin from August 2024 to July 2025 in Department of Critical Care Medicine, Sun Yat-sen Memorial Hospital were prospectively enrolled. Clinical data was collected, including general information such as gender, age and underlying medical history, vital signs at enrollment, Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Sequential Organ Failure Assessment (SOFA) score, laboratory and imaging results, infection-related indicators, and major treatment measures. Peripheral blood samples were collected after enrollment to detect endotoxin concentration. All patients were followed up for 28 days (follow-up assessments were conducted every 14 days following enrollment). The primary outcome was death within 28 days. Secondary outcomes were as follows: length of ICU stay, total hospital stay, and duration of mechanical ventilation. The relationship between different endotoxin levels and early prognosis in sepsis patients was analyzed. The X-tile software was used to determine the optimal cut-off value of endotoxin.Based on this cutoff value, patients were divided into a high-endotoxin group and a low-endotoxin group. Kaplan-Meier curves were plotted to calculate the 28-day cumulative survival rate and mortality rate. Univariate and multivariate Cox proportional hazards regression models were adopted to explore independent risk factors of early survival of sepsis patients.

Among all enrolled patients, there were 101 males and 49 females, with the age of [M (Q₁, Q₃)] 60.0 (53.0, 72.8) years old. The cut-off value of endotoxin, calculated using X-tile software, was 0.23 EU/ml. Based on this value, the subjects were divided into the high-endotoxin group (n=26) and the low-endotoxin group (n=124). The 28-day mortality rate of the high-endotoxin group was significantly higher than that of the low-endotoxin group (42.3% vs 19.4%, P=0.004). There were no statistically significant between-group differences in the secondary outcome indicators, including ICU stay duration, total hospital stay, and duration of mechanical ventilation. The Kaplan-Meier curve showed that the 28-day cumulative survival rate of the high-endotoxin group was lower than that of the low-endotoxin group (57.7% vs 80.6%, P=0.004). The results of multivariate Cox regression analysis indicated that endotoxin (HR=2.307, 95%CI: 1.074-4.958), SOFA score (HR=1.172, 95%CI: 1.063-1.294), and total bilirubin (HR=1.004, 95%CI: 1.001-1.008) were influencing factors for early prognosis in sepsis patients.

Plasma endotoxin has the potential to serve as a promising biomarker for early prognostic assessment of sepsis.

To evaluate markers of cerebral small vessel disease (SVD), cerebral blood flow (CBF), and white matter integrity in patients with subcortical ischemic vascular dementia (SIVD) using multimodal magnetic resonance imaging (MRI), and to analyze the impact of total SVD load on cerebral perfusion and white matter injury. Fifty SIVD patients who visited the Cognitive Disorders Clinic of Tianjin Medical University General Hospital between October 2017 and October 2022 were enrolled and underwent 3.0 T multimodal MRI examination. A total SVD load score was calculated based on the severity of white matter hyperintensities (WMH), lacunes, enlarged perivascular space (EPVS), and cerebral microbleeds (CMB). The patients were divided into a low total SVD load group (0-4 points, n=32) and a high total SVD load group (5-6 points, n=18). CBF and white matter integrity were assessed using arterial spin labeling (ASL) and diffusion tensor imaging (DTI), respectively. Independent-sample t-test and χ² test were used for intergroup comparison. Binary logistic regression model was adopted to analyze the correlation of various imaging markers with CBF and DTI parameters in all subjects. Compared with the low total SVD load group, the high total SVD load group exhibited reduced CBF in the right cerebellar posterior lobe and tonsil [(45.7±14.9) vs (59.6±12.5) ml·(100 g)^-1·min^-1, t=3.52, P<0.01], left superior frontal gyrus [(22.2±6.3) vs (26.8±6.0) ml·(100 g)^-1·min^-1, t=2.55, P=0.01], left middle frontal gyrus [(50.6±15.8) vs (60.5±14.8) ml·(100 g)^-1·min^-1, t=2.22, P=0.03], and right middle frontal gyrus [(58.7±16.1) vs (67.7±12.7) ml·(100 g)^-1·min^-1, t=2.18, P=0.04]. Decreased fractional anisotropy values (all P<0.05) and increased mean diffusivity values (all P<0.05) were observed in multiple white matter regions, including the corpus callosum, right cerebral peduncle, bilateral internal capsules, bilateral anterior corona radiata, bilateral posterior corona radiata, bilateral posterior thalamic radiation, bilateral cingulate gyri, and bilateral frontoparietal superior fasciculi. Meanshile, reduced CBF and impaired white matter integrity in these brain regions were correlated with scores of individual SVD markers and the total SVD load score (all P<0.05). The total SVD load is closely associated with decreased cerebral perfusion and impaired white matter integrity in SIVD patients, which is an important pathological mechanism underlying brain dysfunction.

Clinical data of 3 patients with refractory systemic lupus erythematosus (rSLE) who received chimeric antigen receptor T-cell (CAR-T) therapy at the Department of Rheumatology and Immunology, the First Affiliated Hospital of University of Science and Technology of China, from June to September 2024 was prospectively enrolled. After lymphodepleting preconditioning with cyclophosphamide combined with fludarabine, 2 patients received a low dose (0.5×10⁶/kg) and 1 patient received a medium dose (1.0×10⁶/kg) of a 4th-generation CAR-T cells (SCAR02) targeting cluster of differentiation 19 (CD19) and B-cell maturation antigen (BCMA) and secreting interleukin-6 (IL-6) antibodies. Follow-up was conducted at day 14 and months 1, 2, 3, 6, 9, and 12 post-infusion to systematically evaluate safety (including treatment-related adverse events, cytokines, and immunoglobulin levels) and efficacy (including cellular kinetics, clinical efficacy, and serological markers). All 3 patients were females, aged 37, 25, and 41 years, respectively. During the follow-up period, no cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), or other serious adverse events occurred. CAR-T cells expanded well in all patients; peripheral blood CD19⁺ B cells were completely depleted on days 9-13 and gradually recovered over 3-5 months. By month 12, the SLE Disease Activity Index 2000 (SLEDAI-2K) scores of patients 1 to 3 decreased from 8, 8, and 9 at baseline to 0, 4, and 0, respectively; anti-double-stranded DNA antibodies all turned negative, and complement levels returned to normal. Two patients achieved drug-free complete remission based on the Definitions of Remission in SLE (DORIS) criteria, and 1 patient achieved an SLE Responder Index-4 (SRI-4) response. This study demonstrates that SCAR02 exhibits a good safety profile and preliminary efficacy in rSLE patients, and its function of secreting IL-6 antibodies may help alleviate CRS.

Diabetic foot ulcer (DFU) is one of the chronic complications of diabetes with severe and high treatment cost. Its refractory nature is closely related to the persistent inflammatory response and tissue repair disorders caused by local microenvironment disorders. As key messenger molecules in the immune system, cytokines play an important role in the occurrence, development and healing of DFU by regulating inflammation, angiogenesis and tissue remodeling. In this paper, the role of cytokines in the main pathophysiological mechanisms of DFU was systematically described, and the pathological changes such as the imbalance of pro-inflammatory and anti-inflammatory factors, abnormal expression of growth factors and abnormal infiltration of immune cells mediated by chemokines were analyzed emphatically. At the same time, the feasibility of cytokines as potential biomarkers of wound persistence was discussed. In terms of therapeutic strategies, the new progress of cytokine intervention was systematically summarized, including the research status and application prospects of anti-inflammatory regulation, regenerative factor supplementation and combination therapeutic strategies in animal experiments and clinical trials. This paper expounds the dynamic imbalance of cytokine network in DFU and the new strategy of multi-target and combinatorial diagnosis and treatment based on this network, which provides a new theoretical framework and practical path for precise intervention and clinical translation of DFU.

A 45-year-old female was seen in Peking Union Medical College Hospital on Feb. 21, 2025 due to "abdominal distension and vomiting for 3 months". From January 2025, the patient experienced abdominal distension, the efficacy of oral omeprazole and mosapride was poor, the symptoms gradually worsened and vomiting after eating occurred, the serum albumin decreased from 39 g/L to 16 g/L, and the body weight decreased by 10 kg. Nothing special in the past. Physical examination: Left abdominal and periumbilical tenderness. Gastroscopy: chronic superficial atrophic gastritis. Intestinal ultrasound: The small intestinal wall of groups 2 to 4 was thickened, the thickest part was 0.7 cm, and a strip of blood flow signal was seen in the intestinal wall. Abdominopelvic enhanced CT: Multiple intestinal wall thickening of the small intestine in the proximal abdominopelvic cavity, accompanied by mucosal enhancement, and some intestinal lumen slightly dilated (Figure 1, indicated by arrows). Intestinal protein loss imaging: positive, the site of protein loss was the small intestine of group 3. Enteroscopy: Group 3 small intestinal mucosal congestion and edema with segmental annular cavity superficial ulcer covered with white mucus (Figure 2); Mucosal biopsy was performed at the lesion, and pathology showed a large number of plasma-like cell infiltration and powder-stained amorphous material deposition in the mucosa (hematoxylin-eosin staining ×10) (Figure 3, indicated by arrows). Immunohistochemistry: AE1/AE3 (epithelial +), CD3 (scattered +), CD20 (scattered +), CD138 (+), Mum-1 (+), Kappa (+), Lambda (-), Ki-67 (index5%), CD21 (-), CyclinD1 (-), CD19 (partial +), CD56 (-), LCA (+), CD117 (-). Special staining: Congo red (weak +), alcoholized Congo red (weak +), Masson (-). Bone marrow biopsy showed no tumor involvement. The final diagnosis was mucosa-associated lymphoid tissue (MALT) extranodal marginal zone lymphoma with plasmacytoid differentiation and amyloid deposition. The patient was treated with ortuzumab combined with orelabrutinib and lenalidomide. The patient's disease progressed after 3 cycles of treatment; Therefore, the regimen was changed to rituximab combined with bendamustine. After 2 cycles of treatment, the patient's symptoms improved not significantly. During this period, the anorexia gradually worsened and the patient had intermittent fever. The serum albumin was 20 g/L on re-examination, which was only slightly higher than that before treatment. Thereafter, the patient returned to the local area to continue chemotherapy (specific protocol unknown) and was lost to follow-up on 29 Aug 2025. Primary small intestinal MALT extranodal marginal zone lymphoma is rare, and hypoalbuminemia and long intestinal involvement are associated with poor prognosis. In addition to the tumor itself, fibrous stenosis secondary to repeated chronic inflammation adjacent to the tumor can also lead to persistent abdominal pain, vomiting and other symptoms, and the response to drug treatment is poor. Some patients can surgically remove the diseased intestinal segment to improve their quality of life.