Splenic histology and histopathology: an update

Effect of Flavonols of Aronia melanocarpa Fruits on Morphofunctional State of Immunocompetent Organs of Rats under Cyclophosphamide-Induced Immunosuppression

Aronia melanocarpa berries contain many compounds with potential benefits for human health. The food flavonoids quercetin and rutin, found in significant amounts in the fruits of A. melanocarpa, are known to have favourable effects on animal and human organisms. However, data on the effect of flavonols isolated from black chokeberry on immune functions during immunosuppression are not available in the literature. Thus, the aim of this study was to evaluate the effect of flavonol fraction isolated from A. melanocarpa fruits, in comparison with pure quercetin and rutin substances, on the dysfunctional state of rat thymus and spleen in immunodeficiency. The study was performed on Wistar rats. The animals were orally administered solutions of the investigated substances for 7 days: water, a mixture of quercetin and rutin and flavonol fraction of A. melanocarpa. For induction of immunosuppression, the animals were injected once intraperitoneally with cyclophosphamide. Substance administration was then continued for another 7 days. The results showed that under the influence of flavonols, there was a decrease in cyclophosphamide-mediated reaction of lipid peroxidation enhancement and stimulation of proliferation of lymphocytes of thymus and spleen in rats. At that, the effect of the flavonol fraction of aronia was more pronounced.

Sea Conch Peptides Hydrolysate Alleviates DSS-Induced Colitis in Mice through Immune Modulation and Gut Microbiota Restoration

Inflammatory bowel disease (IBD) is a persistent, lifelong inflammation of the digestive system. Dextran sulfate sodium is commonly used to induce colitis in experimental animal models, which causes epithelial damage, intestinal inflammation, mucin depletion, and dysbiosis of the gut microbiota. Various prebiotics, polysaccharides, and polypeptides are used for IBD treatment. In this study, we used a murine model utilizing BALB/c mice, with 10 mice per group, to investigate the treatment effect of sea conch peptide hydrolysate (CPH) on DSS-induced colitis mice. Colitis was induced through the administration of 2.5% DSS in drinking water over a seven-days period. Furthermore, on the eighth day of the experiment, sea conch peptide hydrolysate (CPH) at low (100 mg/kg), medium (200 mg/kg), and high (400 mg/kg) doses, which were continued for 14 days, were assessed for medicinal purposes in DSS-induced colitis mice. Our results showed that CPH treatment significantly alleviated the severity and symptoms of colitis. The epithelial integrity and histological damage were improved. Intestinal inflammation and inflammatory cell infiltration were improved. Furthermore, the expression of pro-inflammatory cytokines was reduced, and intestinal barrier integrity was restored by elevating the tight junction proteins. Moreover, 16s RNA sequencing revealed dysbiosis of the gut microbiota was observed upon DSS treatment, which was reinstated after CPH treatment. An increased level of Firmicutes and Lactobacillus was observed in the treatment groups. Finally, our results suggest that CPH would be recommended as a functional food source and also have the potential to be used as a medicinal product for different gastrointestinal disorders.

Structural characterization of a sulfated polysaccharide from Ishige okamurae and its effect on recovery from immunosuppression

A sulfated polysaccharide from the brown alga Ishige okamurae Yendo, designated IOY, was successfully isolated by anion-exchange and size-exclusion chromatography. Chemical and spectroscopic analyses demonstrated that IOY was a fucoidan, that consisted of →3)-α-l-Fucp-(1→, →4)-α-l-Fucp-(1→, →6)-β-d-Galp-(1 → and →3)-β-d-Galp-(1 → residues with sulfate groups at C-2/C-4 the of (1 → 3)-α-l-Fucp and C-6 the of (1 → 3)-β-d-Galp residues. IOY possessed a potent immunomodulatory effect in vitro as measured by lymphocyte proliferation assay. The immunomodulatory effect of IOY was further investigated in vivo using immunosuppressed mice induced by cyclophosphamide (CTX). The results showed that IOY significantly increased the spleen and thymus indexes and alleviated CTX-induced spleen and thymus damage. Furthermore, IOY had a significant effect on hematopoietic function recovery and promoted the secretion of interleukin-2 (IL-2) and tumor necrosis factor (TNF-α). Notably, IOY reversed CD4+ and CD8+ T cell reduction and improved immune response. These data indicated that IOY had vital in immunomodulatory function and could be used as drug or functional food to lessen chemotherapy-induced immunosuppression.

Shrimp peptide hydrolysate modulates the immune response in cyclophosphamide immunosuppressed mice model

Bioactive peptides are naturally found in various foods and were shown to have various distinct physiological as well as medicinal benefits. In this study shrimp peptide hydrolysate (SPH) was prepared to investigate its immunomodulatory effect against cyclophosphamide (CTX) induced immunosuppressed mice. The SPH effect was also analyzed on murine macrophage (RAW264.7 cells). The findings show that SPH stimulates macrophages to form multiple pseudopodia, has no cytotoxic effect, and increases phagocytic activity in RAW264.7 cells. Furthermore, the immunosuppressed in-vivo model illustrates the improvement in various aspects, that is body weight, escalation in immune organ index, and ameliorates histopathological transformation of thymus along with the spleen. SPH enhances cell-mediated immunity by facilitating splenocyte proliferation and inhibit excessive apoptosis. Moreover, the significant outcome had been observed with the upregulation of cytokines interferon-gamma (IFN-ϒ), interleukin-2 (IL-2) level and simultaneously downregulate certain genes include interleukin-4 (IL-4) and interleukin-10 (IL-10). Additionally, SPH expedites cellular immunity by enhancing the regulation of immunoglobulin A (IgA) and immunoglobulin M (IgM). However, these findings support the hypothesis that SPH is an effective immunomodulatory agent capable of preventing immune system hypofunction. It is necessary to investigate the detailed mechanism to rule out any unforeseen effects of SPH in future research. PRACTICAL APPLICATIONS: Chemotherapy medications, despite their dominating detrimental effects of damaging immunological organs such as the spleen and thymus, extend the treatment process as well as the destruction of the self-immune system. This study found that SPH is an effective immunomodulatory agent capable of avoiding immune organ hypofunction and improving cell mediate immunity by enhancing macrophage activation, phagocytosis, spleenocyte proliferation, suppressing apoptosis, and elevating cytokines and antibodies. As a result, SPH can be utilized as a nutritional and functional dietary supplement to boost immunological modulation in combination with chemotherapy medications in order to lessen their adverse effects.

Effects of Shrimp Peptide Hydrolysate on Intestinal Microbiota Restoration and Immune Modulation in Cyclophosphamide-Treated Mice

The gut microbiota is important in regulating host metabolism, maintaining physiology, and protecting immune homeostasis. Gut microbiota dysbiosis affects the development of the gut microenvironment, as well as the onset of various external systemic diseases and metabolic syndromes. Cyclophosphamide (CTX) is a commonly used chemotherapeutic drug that suppresses the host immune system, intestinal mucosa inflammation, and dysbiosis of the intestinal flora. Immunomodulators are necessary to enhance the immune system and prevent homeostasis disbalance and cytotoxicity caused by CTX. In this study, shrimp peptide hydrolysate (SPH) was evaluated for immunomodulation, intestinal integration, and microbiota in CTX-induced immunosuppressed mice. It was observed that SPH would significantly restore goblet cells and intestinal mucosa integrity, modulate the immune system, and increase relative expression of mRNA and tight-junction associated proteins (Occludin, Zo-1, Claudin-1, and Mucin-2). It also improved gut flora and restored the intestinal microbiota ecological balance by removing harmful microbes of various taxonomic groups. This would also increase the immune organs index, serum levels of cytokines (IFN-ϒ, IL1β, TNF-α, IL-6), and immunoglobin levels (IgA, IgM). The Firmicutes/Bacteroidetes proportion was decreased in CTX-induced mice. Finally, SPH would be recommended as a functional food source with a modulatory effect not only on intestinal microbiota, but also as a potential health-promoting immune function regulator.

Modulating effects of the synergistic combination of extracts of herbal drugs on cyclophosphamide-induced immunosuppressed mice

OBJECTIVE

Taking leads from the available research, we aimed to develop a synergy-based herbal combination of Tinospora cordifolia (TC), Phyllanthus emblica (PE), and Piper nigrum (PN). Also, evaluating their synergistic effect on CP-induced immunosuppression in mice model and exploring the possible mechanisms involved in reversing the damage.

METHODOLOGY

The immunomodulatory activity of combination, of TC stem, PE fruits, and PN dried fruits, was determined by in vitro assays (splenocyte proliferation and pinocytic activity of peritoneal macrophages of mice) and in vivo study using CP-induced immunosuppression model in Swiss Albino mice. The ratio was optimized for combining three by in vitro MTT assay. The combination was further evaluated for anti-oxidant activity by DPPH scavenging method and quantified for its bioactive metabolites by HPTLC. Serum collected on day 0, 4, 7 and 14 was employed for estimation of haematogram (haematocrit, TLC, DLC, and haemoglobin, etc) and immune parameters (IL-10, IL-6 and TNF-α) by ELISA.

RESULTS

The study demonstrated, that combination of herbal extracts at an intermediate dose could inhibit the proliferation of spleen cells and peritoneal macrophages (P ≤ 0.0001) and induce suppression of pro-inflammatory mediators, and also certified that combination exerts synergized effects. The results showed that the combination possess potential antioxidant activity by DPPH scavenging method (IC50-113.5 µg/ml). It was identified that combination significantly (P ≤ 0.0001) improved the immune markers, haematogram parameters, and histological parameters, with maximum protection offered by an intermediate dose.

CONCLUSION

The results suggested that present combination could be further explored clinically as potent synergy-based therapeutic approach for immune modulation.

Influence of icariin on inflammation, apoptosis, invasion, and tumor immunity in cervical cancer by reducing the TLR4/MyD88/NF-κB and Wnt/β-catenin pathways

Background

Cervical cancer is a type of the most common gynecology tumor in women of the whole world. Accumulating data have shown that icariin (ICA), a natural compound, has anti-cancer activity in different cancers, including cervical cancer. The study aimed to reveal the antitumor effects and the possible underlying mechanism of ICA in U14 tumor-bearing mice and SiHa cells.

Methods

The antitumor effects of ICA were investigated in vivo and in vitro. The expression of TLR4/MyD88/NF-κB and Wnt/β-catenin signaling pathways were evaluated.

Results

We found that ICA significantly suppressed tumor tissue growth and SiHa cells viability in a dose-dependent manner. Also, ICA enhanced the anti-tumor humoral immunity in vivo. Moreover, ICA significantly improved the composition of the microbiota in mice models. Additionally, the results clarified that ICA significantly inhibited the migration, invasion capacity, and expression levels of TGF-β1, TNF-α, IL-6, IL-17A, IL-10 in SiHa cells. Meanwhile, ICA was revealed to promote the apoptosis of cervical cancer cells by down-regulating Ki67, survivin, Bcl-2, c-Myc, and up-regulating P16, P53, Bax levels in vivo and in vitro. For the part of mechanism exploration, we showed that ICA inhibits the inflammation, proliferation, migration, and invasion, as well as promotes apoptosis and immunity in cervical cancer through impairment of TLR4/MyD88/NF-κB and Wnt/β-catenin pathways.

Conclusions

Taken together, ICA could be a potential supplementary agent for cervical cancer treatment.

Conventional Ultrasound and Contrast-Enhanced Ultrasound in the Diagnosis of Splenic Diseases: A Systematic Review and Meta-analysis

Accurate diagnosis of splenic diseases is important for timely and accurate treatment. The objective of this study was to compare the accuracy of contrast-enhanced ultrasound (CEUS) and conventional ultrasound (US) in detecting splenic lesions. A systematic literature search was undertaken, and 8 studies met the inclusion criteria. The sensitivity and specificity of the consolidated results of CEUS were 0.95 (95% confidence interval [CI], 0.92-0.97) and 0.97 (95% CI, 0.90-0.99), respectively (I² = 27.4%; area under the curve [AUC] from a summary receiver operating characteristic curve = 0.97). The sensitivity and specificity of the consolidated results of conventional US were 0.70 (95% CI, 0.56-0.80) and 0.96 (95% CI, 0.76-0.99; I² = 83.4%; AUC = 0.84). In this systematic review and meta-analysis, the sensitivity and specificity of CEUS were higher than those of conventional US in diagnosing splenic lesions. Contrast-enhanced US is a promising method for accurately diagnosing splenic lesions.

Lymphoepithelial cyst of the pancreas: A challenging diagnosis on fine needle aspiration

Lymphoepithelial cysts (LECs) of the pancreas are rare, benign pancreatic cysts comprising approximately 0.5% of all pancreatic cysts. They occur predominantly in men in the 5th and 6th decades of life. LECs are true cysts lined by stratified squamous epithelium with adjacent subepithelial lymphoid tissue. They range in size from 1.2 to 17 cm (mean size 4.6 cm) and can arise in any part of the pancreas. 1 LEC resembles other benign and malignant pancreatic cysts clinically and radiologically. The cytomorphologic features of LECs have been described in a small number of case reports and it has been indicated that features may overlap with other benign and malignant pancreatic lesions. Herein, we report clinical, radiological, cytological and histopathological features of a pancreatic LEC in a 62-year-old male.

Two different fucosylated chondroitin sulfates: Structural elucidation, stimulating hematopoiesis and immune-enhancing effects

Two fucosylated chondroitin sulfates FCS_hp and FCS_ht were isolated from the sea cucumber Holothuria polii and Holothuria tubulosa, respectively. The NMR spectroscopy and HILIC-FTMS methods were applied for their detailed structural characterization. Chemical analysis indicated that the two FCSs all contained a chondroitin sulfate backbone chondroitin sulfate-like core and fucosyl branches of α-L-Fuc2,4S, α-L-Fuc4S or α-L-Fuc3,4S linked to O-3 of glucuronic acid residues. The main branches of FCS_hp and FCS_ht were monofucose, and the small amounts of di-, tri- and tetrafucose with α-1,3-linkage type were also detected. Finally, we investigated the immunomodulatory function of FCS_hp and FCS_ht in cyclophosphamide (CTX)-induced immunosuppressed mouse models. The results showed that FCS_hp and FCS_ht had beneficial effects on hematopoietic function recovery in CTX-induced bone marrow suppression mice. Notably, the α-L-Fuc2,4S was more important to the activity than α-L-Fuc3,4S. These results provided basis for developing the drugs to reduce side effects of chemotherapy.

Laparoscopic spleen-preserving pancreatic resection for intrapancreatic accessory spleen: Case report

INTRODUCTION

Intrapancreatic accessory spleen (IPAS) has been rarely noted radiologically because the spatial resolution of conventional images was low. The infrequent presence of the accessory spleen in the pancreatic tissue could lead to inappropriate diagnosis, thereby necessitating a therapeutic approach. The present study reported such cases and summarized the available imaging findings to reduce unnecessary invasive surgeries.

PATIENT CONCERNS

The patient's complaint was "a pancreatic mass was found for half a month."

DIAGNOSIS

IPAS was eventually diagnosed by pathology.

INTERVENTIONS

Laparoscopic spleen-preserving pancreatic resection.

OUTCOMES

Postoperative course was uneventful and the patient was discharged from our hospital after 10 days.

CONCLUSIONS

When an asymptomatic pancreatic mass is detected, the diagnosis of IPAS should not be excluded, especially if the lesion has the same imaging features as the spleen. As a definite diagnosis of IPAS is difficult by a single examination, multiple techniques might be essential.

Epidermoid cyst in intrapancreatic accessory spleen: A systematic review

BACKGROUND/OBJECTIVES

Due to its rarity, epidermoid cyst in intrapancreatic accessory spleen (ECIPAS) is still a diagnostic dilemma during clinical practice. The aim of this review was to summarize the epidemiologic features and management of ECIPAS.

METHODS

MEDLINE and EMBASE were searched for English articles reporting on ECIPAS up to April 30th, 2018 following the methodology suggested by the PRISMA guidelines. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).

RESULTS

A total of 56 patients from 47 full articles were included for the final data synthesis. More than half of the ECIPASs (59%) were found incidentally. The female/male ratio was 1.33. ECIPAS is typically a single mono-/multi-lobular cystic lesions in the pancreatic tail with thickened cystic wall or various amount of solid component which had identical density/signal to the spleen on imaging examinations. The cyst is filled with serous or non-serous fluid. Recognition of the surrounding ectopic splenic tissue is the key point to diagnose ECIPAS. However, no preoperative examination was able to make a definite diagnosis. Almost all the patients (96%) received surgical treatment, due to the suspicion of pancreatic malignant or potentially malignant cystic tumor, especially mucinous cystic neoplasm (MCN).

CONCLUSIONS

Although seldom encountered, ECIPAS should be considered as a differential diagnosis for pancreatic cystic lesions, especially when solid component was detected. As a benign disease, unnecessary surgery should be avoided. Because it is difficult to make a definite diagnosis preoperatively by one single examination, multiple modalities may be required.

Intrapancreatic accessory spleen: a diagnostic dilemma

BACKGROUND

As intrapancreatic accessory spleen (IPAS) is rarely encountered during clinical practice, the aim of this review was to summarize the epidemiologic features, the diagnosis and treatment of IPAS.

METHODS

MEDLINE and EMBASE were searched for articles reporting on IPAS. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).

RESULTS

A total of 105 patients were included, of which 73% were detected incidentally. The male/female ratio was 1.23. The size of IPAS in patients who had previously undergone splenectomy was larger than that of patients without prior splenectomy (2.5 cm vs 1.5 cm; p = 0.020). No preoperative examination was able to make a definite diagnosis for all IPASs. More than half of the patients (55%) received surgical treatment, most of which (87%) were suspected as pancreatic neuroendocrine tumors (p-net) preoperatively.

CONCLUSIONS

Although rare, IPAS should be considered in the differential of patients with suspected incidental p-net, especially if there has been a past history of splenectomy. Preoperative diagnosis is important as unnecessary surgery can be avoided. As it is difficult to make a definite diagnosis of IPAS by one single examination, multiple techniques may be required.

Immunomodulatory effect of Schisandra polysaccharides in cyclophosphamide-induced immunocompromised mice

As a strategy to prevent the well-known immunosuppressant effects of cyclophosphamide (Cyp), the immunomodulatory effects of the polysaccharide extract of the fruit of Schisandra chinensis (Turcz.) Baill. were investigated in the present study. The crude Schisandra polysaccharide (SCP) was obtained by water extraction and alcohol precipitation methods. The total carbohydrate, uronic acid and protein contents were determined using the phenol-sulfuric acid, m-hydroxydiphenyl and Bradford method, respectively. The monosaccharide composition of SCP was determined by high-performance liquid chromatography. ICR mice were randomly divided into control, model, low-dose SCP (0.4 mg/10 g), medium-dose SCP (0.8 mg/10 g) and high-dose SCP (1.6 mg/10 g) groups. The mice in the SCP groups were intragastrically administered SCP once a day for 21 days and those from the control and model groups were administered the same volume of distilled water. Subsequently, the mice in the model and SCP groups were intraperitoneally injected with Cyp (20 mg/kg) once a day for 5 days. The mouse leukocyte count in the peripheral blood as well as thymus and spleen indexes were determined, and the phagocytic function of macrophages was estimated using a carbon clearance test. The thymus and spleen were histomorphologically observed. The levels of tumor necrosis factor-α and interferon-γ were measured by ELISA. Furthermore, antibody formation and spleen lymphocyte proliferation were measured by the serum hemolysin and the MTT method, respectively. The apoptotic rate of splenic lymphocytes was determined by flow cytometric analysis. The results indicated that SCP prevents Cyp-induced impairment of the cellular, humoral and non-specific immunity, and may be an auxiliary immune enhancer for the prevention of immune hypofunction.

Clinicopathological analysis of primary splenic diffuse large B-cell lymphoma

Splenic infiltration is often seen in diffuse large B-cell lymphoma (DLBCL). However, primary splenic DLBCL is rare and studies on its clinicopathological features are limited. We assessed 66 cases of primary splenic DLBCL and 309 control DLBCL, not otherwise specified. Hepatitis C virus antibody prevalence, B symptoms, poor performance status and CD5 positivity differed significantly between the primary splenic DLBCL and control DLBCL groups. Primary splenic DLBCL cases were classified histopathologically into two groups [white pulp pattern (n = 46), red pulp pattern (n = 20)]. Survival analysis showed no difference in overall survival between the primary splenic DLBCL and the control group, but the former had a more favourable progression-free survival. In the examination of primary splenic DLBCL, the white pulp pattern was statistically associated with a lower performance status (2-4), and a lower CD5 positivity than the red pulp pattern. In the survival analysis, the red pulp pattern demonstrated poorer overall survival. Multivariate analysis of overall survival in primary splenic DLBCL cases identified CD5 positivity as an indicator of poor prognosis. Classifying primary splenic DLBCL into white and red pulp patterns was useful in terms of clinicopathological features and overall survival.

Intrapancreatic accessory spleen: utilization of fine needle aspiration for diagnosis of a potential mimic of a pancreatic neoplasm

Accessory spleen (AS) is not a rare occurrence, and with the second most common site being the tail of the pancreas, intrapancreatic AS (IPAS) can easily mimic a pancreatic neoplasm. Together with radiologic imaging findings, endoscopic ultrasound-guided fine needle aspiration (FNA) can be used to assist in the diagnosis, preventing potentially unnecessary surgical procedures. The most common cytologic findings that have been described in the literature include a heterogenous population of small lymphocytes along with traversing small vessels. Immunohistochemical staining for CD8 has also been documented as a useful tool to support the diagnosis as it specifically highlights the endothelial cells of the splenic sinus. Here, we report two additional cases of IPAS diagnosed by FNA and discuss the potential pitfalls in diagnosis of this entity.

Diagnosis of hypersplenism with the epinephrine stimulation test

PRINCIPLES: Hypersplenism can be defined by thrombocytopenia and/or neutropenia resulting from blood cell sequestration in an enlarged spleen. In multimorbid patients the differential diagnosis of cytopenia is challenging and currently there is no established test for diagnosing hypersplenism. METHODS: The epinephrine stimulation test (EST) measures changes in platelets, neutrophil counts and spleen size following a subcutaneous epinephrine injection. We retrospectively analysed the results of EST in 228 patients. RESULTS: Increases in neutrophils and platelets after epinephrine injection were significantly greater in patients with enlarged than in patients with normal size spleens. Using cutoffs of low, intermediate and high confidence EST was positive in 69.8% vs. 41.3% (low confidence), 49.6% vs. 17.4% (intermediate confidence) and 38.8% vs. 10.9% (high confidence) in patients with enlarged vs. normal size spleens. Changes in platelet and neutrophil counts correlated with each other and with changes in spleen size, confirming cell release from the spleen during EST. When stratified according to the underlying diagnosis, patients with liver disease had the strongest response to EST, patients with malignant haematological diseases the weakest. In addition the response to EST was significantly related to changes in platelet and neutrophil counts after splenectomy, confirming the validity of our test. No serious side effects occurred during EST. CONCLUSION: When used in a large patient cohort, EST is a safe and simple diagnostic test. In this exploratory study EST is of value in evaluating patients with cytopenia and a positive EST argues strongly for hypersplenism. Future studies should prospectively evaluate EST for the management of patients with splenomegaly.

Large platelet aggregates in endoscopic ultrasound-guided fine-needle aspiration of the pancreas and peripancreatic region: a clue for the diagnosis of intrapancreatic or accessory spleen

Intrapancreatic and intraabdominal accessory spleens (IPIASs) are rarely encountered in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsies. However, as incidentally discovered IPIAS can mimic a benign or malignant pancreatic neoplasm on imaging studies, a definitive diagnosis made by EUS-FNA can avert an unnecessary surgical intervention or additional radiologic follow-up. We report five cases of intrapancreatic splenules and one case of accessory spleen (AS) in which a definitive diagnosis was made on EUS-FNA. Previously recognized FNA cytomorphologic features of splenic tissue, including ASs and splenosis, are endothelial cells and polymorphous lymphocytes admixed with neutrophils, eosinophils, plasma cells, histiocytes, and lymphoglandular bodies. We describe the additional finding of abundant large platelet aggregates as another distinguishing feature of splenic tissue on FNA. In all six cases, large platelet aggregates were identified along with polymorphous lymphoid cells, lymphoglandular bodies, loose aggregates of endothelial cells and scattered or aggregated bland spindle cells. A review of 10 consecutive cases of EUS-FNA-sampled benign intraabdominal lymph nodes showed that the presence of large platelet aggregates, three-dimensional aggregates of lymphoid cells and of bland slender spindle cells and the absence of follicular germinal cell components (tingible body macrophages and lymphohistiocytic aggregates) are useful in differentiating IPIASs from reactive lymph nodes. Immunoperoxidase stains were useful to confirm a suspected IPIASs by showing CD31-positive acellular flocculent material, consistent with large platelet aggregates and a rich CD8-positive endothelial cell network between CD45-positive lymphoid cells and CD68-positive histiocytes in all six cases.

Fine-needle aspiration of intrapancreatic accessory spleen, mimic of pancreatic neoplasms

Intrapancreatic accessory spleen (IPAS) is a congenital abnormality, which mimics neoplasm. Distinguishing IPAS from pancreatic neoplasm/malignancy is extremely important from a treatment perspective. We report the case of a 67-year-old asymptomatic man who had a 1.3-cm, incidentally detected, pancreatic tail mass. The mass was round, well-circumscribed, and hypervascular with uniform enhancement. The image findings were highly suggestive of a pancreatic endocrine neoplasm. An endoscopic ultrasound-guided fine-needle aspiration was performed. Conventional smears revealed a polymorphous population of lymphocytes admixed with a subset of other inflammatory cells. Hematoxylin-eosin–stained cell block sections showed conspicuous thin-walled blood vessels in addition to inflammatory cells. Immunostaining for CD8 demonstrated strong positivity in endothelial cells of the thin-walled vessels. By correlating the cytologic findings with the result of immunostaining, we rendered the diagnosis of IPAS. Our experience supports the view that endoscopic ultrasound-guided fine-needle aspiration may enable a reliable, preoperative diagnosis of IPAS and thus prevent unnecessary surgery.

[Lymphomas of the spleen]

The spleen is commonly affected by malignant lymphomas and the macroscopic findings of the spleen correlate with different lymphoma entities. However, most lymphomas are not primarily diagnosed in splenectomy specimens. Exceptions include splenic marginal zone lymphomas and hepatosplenic T-cell lymphomas that are typically diagnosed from histological findings. In addition, hairy-cell leukemia, LGL leukemia and T-cell prolymphocytic leukemia typically show characteristic patterns of infiltration in the spleen which may be diagnostically useful. The different infiltration patterns of these tumors are discussed here.

Intrapancreatic accessory spleen: mimic of pancreatic endocrine tumor diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy

Intrapancreatic accessory spleen forms a well-defined nodule within the tail of the pancreas and is commonly mistaken by imaging studies as a neuroendocrine tumor. We report three cases of intrapancreatic accessory spleen diagnosed by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) biopsy. Imaging studies showed well-circumscribed nodules in the tail of the pancreas. Two lesions were clinically suspicious for pancreatic neuroendocrine tumors and one appeared to be a cyst. EUS-guided FNA revealed predominantly small lymphocytes with a subset of histiocytes, conspicuous eosinophils, and plasma cells. There was also characteristic CD8 positive immunostaining of endothelial cells in cell block sections. We report the first series of accessory spleen in the pancreas diagnosed by EUS-guided FNA with the aid of CD8 immunostaining of splenic sinus endothelial cells.

Changes in count and function of splenic lymphocytes from patients with portal hypertension

AIM: To investigate changes in numbers and proliferative function of splenic lymphocytes in patients with hypersplenism due to portal hypertension (PH), to provide evidence for further study of immune status of the spleen during PH.

METHODS: Twelve spleens from patients with hypersplenism due to PH served as the PH group, and four spleens from cases of traumatic spleen rupture were regarded as the control group. After weighing the spleen, lymphocytes were separated and counted using a cell counting plate to calculate the lymphocyte count per gram of spleen tissue (relative quantity) and total lymphocyte count in whole spleen (absolute quantity). The immunohistochemical SP method was used to observe the density and distribution of lymphocytes in the spleen. The MTT method was used to observe changes in lymphocyte proliferative function.

RESULTS: As compared to the control group, the splenic lymphocytes in the PH group showed that: (1) There was no difference in distribution but a significant decrease in density; (2) the number of lymphocytes per gram of spleen (relative quantity) decreased significantly [(0.822 ± 0.157) × 10⁸vs (1.174 ± 0.254) × 10⁸, P < 0.01]; (3) with the significant increase in the weight of the PH spleen (832.6 ± 278.2 g vs 211.7 ± 85.6 g, P < 0.01), the total quantity of lymphocytes (absolute quantity) increased significantly [(0.685 ± 0.072) × 10¹¹vs (0.366 ± 0.057) × 10¹¹, P < 0.01]; and (4) the proliferative function of lymphocytes was enhanced: T lymphocytes, (0.022 ± 0.005 vs 0.015 ± 0.003, P < 0.05), and B lymphocytes (0.034 ± 0.006 vs 0.023 ± 0.001, P < 0.01).

CONCLUSION: Although lymphocyte density in the spleen decreased in patients with PH, the total quantity of lymphocytes increased because spleen weight increased greatly, along with the proliferating function. With respect to changes in lymphocytes, PH spleens may still have immune function, although it may be disordered. However, complete evaluation of the immune function of the spleen in PH requires more research.

Recommended curriculum for teaching hematopathology to subspecialty hematopathology fellows

The performance and interpretation of clinical hematology and hematopathology laboratory tests and diagnosis of benign or malignant hematolymphoid disorders present unique challenges to hematopathology fellow trainees. To assist hematopathology fellowship program directors in preparing trainees to meet these challenges, a task force of pathologists with expertise in hematopathology developed a suggested training curriculum that includes a comprehensive list of topics in the areas of analytic hematology, bone marrow pathology, lymph node pathology, splenic pathology, lymphoma diagnostics, cytogenetics, and molecular diagnostics. This report also includes recommendations for training experiences that will facilitate the transition of subspecialty residents to practicing consultants in hematopathology.

Subcutaneous splenosis of the abdominal wall

We report a case of subcutaneous splenosis in the abdominal wall of a 23-year-old oligophrenic man. It presented as a well-demarcated 8 x 7 x 5-cm subcutaneous tumor in the left inguinal area closely above the scar after a previous operation for hernia. The lesion simulated clinically a hernia or a tumor due to its large size and location and, additionally, no history could be taken from the patient due to his mental handicap.

Morphologic and immunohistochemical evaluation of splenic hematopoietic proliferations in neoplastic and benign disorders

Spleen is a common site of extramedullary hematopoiesis. Extramedullary hematopoiesis seen in non-neoplastic conditions can occasionally be extensive and raise concerns for a myeloid neoplasm. We compared the morphologic and immunohistochemical features of splenic hematopoietic proliferations seen in neoplastic myeloid disorders (eg chronic myeloproliferative disorders, myelodysplastic/myeloproliferative disorders and acute myeloid leukemias) to extramedullary hematopoiesis seen in a variety of reactive conditions. In all, 80 spleen specimens were reviewed. The presence of each marrow-derived lineage, dysplasia and immunohistochemical results were evaluated (CD34, CD117, myeloperoxidase, CD68, p53, TdT, CD42b and hemoglobin). Neoplastic hematopoietic proliferations in chronic myeloproliferative disorders are characterized by trilineage hematopoiesis with significant dysplasia in all cell lineages. Acute myeloid leukemia showed an increase in immature forms, which were highlighted by immunohistochemistry. Reactive extramedullary hematopoiesis showed variability in histologic features. Post-bone marrow transplant and thrombotic thrombocytopenic purpura/hemolytic-uremic syndrome spleens showed extramedullary hematopoiesis with some morphologic features of immaturity, which could simulate chronic myeloproliferative disorder. However, they lacked characteristic immunohistochemical features of neoplastic myeloid disorders such as positivity for CD34 or CD117.

Histopathology of the spleen in T-cell large granular lymphocyte leukemia and T-cell prolymphocytic leukemia: a comparative review

We review retrospectively the spleen histology in 8 patients with T-cell large granular lymphocyte (LGL) leukemia and 4 with T-cell prolymphocytic leukemia (T-PLL) to identify characteristic patterns of involvement and to distinguish such patterns from those described in other low grade B- and T-cell malignancies. Moderate splenic enlargement with red pulp expansion due to lymphocytic infiltration was characteristic of LGL leukemia. Abnormal lymphocytes expressed cytotoxic granule proteins and were consistently CD45RO and CD5 negative in contrast to normal red pulp T cells. This infiltration respected anatomic boundaries with encroachment but no invasion of white pulp areas. Unlike in hairy cell leukemia, the main differential diagnosis for red pulp lymphocytosis, the white pulp was not only preserved in T-cell LGL leukemia but showed germinal center hyperplasia with expansion of the mantle zones. By comparison, T-PLL spleens showed marked red pulp lymphoid infiltration by medium-sized cells with irregular nuclei and prominent eosinophilic nucleoli. T-PLL lymphocytes, unlike LGLs, were more invasive, infiltrating the spleen capsule as well as white pulp areas. T-cell prolymphocytes did not express cytotoxic granule proteins or NK-cell markers, were CD5+, CD45RO+ like normal spleen T cells, were CD2+, CD3+, CD45+, CD43+, TCRbeta+, but CD25-, CD30-, ALK-1-, TRAP-, DBA44-, and TdT-. Expression of CD4 and CD8 in these cells mirrored that of circulating T-PLL cells. These observations on the morphologic and immunohistochemical appearances of the spleen in T-cell LGL leukemia and T-PLL may aid diagnosis of these uncommon T-cell disorders, particularly T-cell LGL leukemia, where presentation may be cryptic and where unique pathognomonic features, are absent.

Splenic hamartoma with bizarre stromal cells

Splenic hamartoma is a rare entity characterized by disorganized red pulp tissue in the absence of interspersed white pulp. We report 3 cases with scattered bizarre stromal cells, a feature not previously reported in the literature. The patients were adults who presented with abdominal pain (2 cases) or were incidentally found to have a splenic mass (1 case). The lesion was solitary, circumscribed, and unencapsulated, comprising disorganized slit-like, tubular, ectatic or cavernous vascular channels. There was a loose stroma that contained lymphocytes, plasma cells, siderophages, and fibrin exudate. Scattered haphazardly were isolated bizarre large cells with oval, convoluted, or multilobated nuclei; pale or smudged chromatin; and scanty cytoplasm. Mitotic figures were not found. The bizarre cells were negative for lymphoid, dendritic cell, histiocytic, myeloid, endothelial, epithelial, and melanocytic markers. Only rare bizarre cells stained for desmin in 1 case. It is important to recognize this morphologic variant of splenic hamartoma in order not to misinterpret the bizarre cells as being indicative of a malignancy.