Frequent CDKN2B/P15 and DAPK1 methylation in duodenal follicular lymphoma is related to duodenal reactive lymphoid hyperplasia.

Duodenal type follicular lymphoma (DFL), a rare entity of follicular lymphoma (FL), is clinically indolent and is characterized by a low histological grade compared with nodal follicular lymphoma (NFL). Our previous reports revealed that DFL shares characteristics of both NFL and mucosa-associated lymphoid tissue (MALT) lymphoma in terms of clinical and biological aspects, suggesting its pathogenesis may involve antigenic stimulation. In contrast to NFL, the genomic methylation status of DFL is still challenging. Here, we determined the methylation profiles of DNAs from patients with DFL (n = 12), NFL (n = 10), duodenal reactive lymphoid hyperplasia (D-RLH) (n = 7), nodal reactive lymphoid hyperplasia (N-RLH) (n = 5), and duodenal samples from normal subjects (NDU) (n = 5) using methylation specific PCR of targets previously identified in MALT lymphoma (CDKN2B/P15, CDKN2A/P16, CDKN2C/P18, MGMT, hMLH-1, TP73, DAPK, HCAD). DAPK1 was frequently methylated in DFL (9/12; 75%), NFL (9/10; 90%), and D-RLH (5/7; 71%). CDKN2B/P15 sequences were methylated in six DFL samples and in only one NFL sample. Immunohistochemical analysis showed that p15 expression inversely correlated with methylation status. Genes encoding other cyclin-dependent kinase inhibitors (CDKN2A/P16, CDKN2C/P18) were not methylated in DFL samples. Methylation of the genes of interest was not detected in DNAs from D-RLH, except for DAPK1, and the difference in the extent of methylation between NDU and D-RLH was statistically significant (P = 0.013). Our results suggest that D-RLH serves as a reservoir for the development of DFL and that methylation of CDKN2B/P15 plays an important role in this process.

Pseudolymphomatous Cutaneous Angiosarcoma Presenting With Persistent Firm Facial Edema in a Patient With Systemic Sclerosis.

ABSTRACT: Pseudolymphomatous cutaneous angiosarcoma (cAS) is a rare subtype characterized by a prominent lymphocytic infiltrate, posing diagnostic challenges due to its resemblance to lymphoid neoplastic processes. We present a novel case highlighting the clinical and histopathological features, notably its association with persistent firm facial edema in a patient with systemic sclerosis (SSc). A 47-year-old woman with a 21-year history of SSc presented with firm palpebral edema evolving to involve the entire face and cervical region over six months. Diagnostic imaging revealed inflammatory changes in orbital regions, supradiaphragmatic lymphadenopathies, and lytic lesions. Skin biopsy demonstrated a diffuse neoplasm with vascular channels and solid areas, accompanied by dense lymphocytic proliferation. Pseudolymphomatous cutaneous angiosarcoma, a rare malignant neoplasm, exhibits variable clinical presentations and rapid progression. Histologically, it manifests as irregularly shaped vascular channels lined by prominent endothelial cells. Immunohistochemistry, particularly markers such as v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG), aids in diagnosis. Notably, this case marks the first presentation of cAS with persistent facial edema in SSc, highlighting the association between SSc and cancer risk. This case underscores the diagnostic challenges posed by cAS and emphasizes the importance of early detection for optimal patient outcomes. Further understanding of its association with autoimmune disorders such as SSc is crucial for comprehensive management strategies.

Florid follicular lymphoid hyperplasia of the palate: review of the literature and report of an illustrative case.

OBJECTIVE: The aim of this report was to review oral follicular lymphoid hyperplasia, with emphasis on palatal lesions. METHOD AND MATERIALS: A comprehensive search was performed on PubMed for case reports and case series of palatal follicular lymphoid hyperplasia published in the English language literature. Relevant data from collated articles was sought, including patient demographics, clinical manifestations, imaging modalities and findings, comorbidities, etiopathogenesis, lesional management, and lesional outcome. A new palatal case has also been provided to illustrate several features of this lesion. RESULTS: In total, 32 cases were assembled to establish clinicopathologic correlations, representing the largest aggregation of published cases. Most of the affected patients were at least 60 years old and with a decisive female predilection. The majority of lesions were ≤ 3 cm, appearing as normal color, purple-red or red, and varied from soft to firm. Notably, 32% of palatal follicular lymphoid hyperplasias were associated with denture wear, and lesional recurrence was recorded in 16% of cases. To date, none of the reported cases of palatal follicular lymphoid hyperplasia has undergone malignant transformation. CONCLUSIONS: Palatal follicular lymphoid hyperplasias often arise as a reactive process. Critical histopathologic and histochemical assessments are necessary to establish benignity. Postoperatively, clinicians should follow patients for at least 5 years for recurrence and remain vigilant for neoplastic change as several published accounts of non-oral follicular lymphoid hyperplasias have undergone malignant transformation, usually to lymphoma.

Cutaneous borreliosis in children - a challenging problem.

Borreliosis, also known as Lyme disease, is a vector-borne disease caused by different species of the Borrelia burgdorferi complex. It is frequent in Europe and Northern America. The major vectors are ixodoid ticks. Paediatric borreliosis is common and peaks in children between five to nine years. In Europe, the leading symptom of early infection is erythema migrans, in contrast to Northern America where arthritis is the dominating clinical finding. In this review, we focus on Europe, where cutaneous borreliosis is mainly caused by infection with B. afzelii. The cutaneous symptoms include erythema migrans, lymphocytoma, chronic atrophic dermatitis and juxta-articular nodules. In children, lymphocytoma is very common but chronic atrophic dermatitis is rare. Clinical symptoms, diagnosis, peculiarities of childhood disease and treatment are also reviewed. It is important to note that after haematogeneic spread, signs of infection may be non-specific, and this is a challenge for diagnosis.

Features of tattoo-associated cutaneous lymphoid hyperplasia on reflectance confocal microscopy and line-field confocal optical coherence tomography.

The popularity of tattoos has led to an increase in associated skin reactions, including complications such as infection, allergic reactions and rare conditions such as tattoo-induced cutaneous lymphoid hyperplasia (CLH). CLH is a benign lymphoproliferative reaction with clinical features resembling malignant cutaneous lymphomas. Non-invasive diagnostic tools like reflectance confocal microscopy (RCM) and the new line-field confocal optical coherence tomography (LC-OCT) are being studied in dermatology better to understand the morphological patterns of many dermatological diseases. Between September 2021 and May 2023, patients with suspicious lesions for tattoo-related CLH were analysed using RCM and LC-OCT before confirming the diagnosis of CLH through skin biopsy and histopathological examination. The study included five cases of CLH. It focused on the analysis of high-quality LC-OCT images/videos and RCM images to investigate the features of CLH in tattooed individuals. Most (80%) cases exhibited a mixed T and B lymphocyte infiltration subtype, while 20% showed a predominant T infiltration subtype. RCM and LC-OCT revealed characteristic features, including architectural disarray, fibrosis, lymphoid infiltrates, and pigment deposits in the epidermis and dermis. Non-invasive tools such as RCM and LC-OCT are valuable in diagnosing tattoo-related CLH. While skin biopsy remains the current standard for diagnosis, RCM and LC-OCT can serve as helpful adjuncts in identifying the most representative area for biopsy. They may potentially become alternative diagnostic options in the future, offering benefits in terms of cost, diagnostic efficiency, aesthetics and patient satisfaction as the prevalence of tattoo-related adverse reactions continues to rise.

Stenotrophomonas maltophilia skin infection in an immunocompetent patient: Primary cutaneous CD30+ T-cell lymphoproliferative disorder or pseudolymphoma?

Cutaneous pseudolymphomas are a wide group of diseases mimicking cutaneous lymphoma. They comprise several skin conditions with different etiopathogenesis, clinical-pathological features, and prognosis, which may occur in the absence of an identifiable trigger factor or after administration of medications or vaccinations, tattoos, infections, or arthropod bites. They present with different manifestations: from solitary to regionally clustered lesions, up to generalized distribution and, in rare cases, erythroderma. They persist variably, from weeks to years, and resolve spontaneously or after antibiotics, but may recur in some cases. CD30+ T-cell pseudolymphomas are characterized by the presence of large, activated lymphoid cells, generally in response to viral infections, arthropod assault reactions, and drug eruptions. Stenotrophomonas maltophilia is a ubiquitous Gram-negative bacillus responsible for opportunistic infections in immunocompromised patients. Infection of intact skin in immunocompetent patients is particularly rare. Here, we report a case of a man presenting an isolated nodule histopathologically mimicking a primary cutaneous CD30+ T-cell lymphoproliferative disorder.

Reactive lymphoid hyperplasia of the liver: A rare case report.

BACKGROUND: Hepatic reactive lymphoid hyperplasia (RLH) is a rare benign lymphoproliferative lesion and a poorly understood disease. It is usually asymptomatic and incidental, but it is difficult to distinguish from hepatocellular carcinoma and metastatic liver tumor on imaging, and percutaneous biopsy is not sufficient to distinguish from low-grade malignant lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), making diagnosis difficult. CASE SUMMARY: A 69-year-old woman came to our hospital for reexamination of pulmonary nodules followed by liver occupation. The lesions showed "wash-in and wash-out" on contrast-enhanced ultrasonography and magnetic resonance imaging. Enhanced magnetic resonance also showed annular envelope enhancement and limited diffusion on the ADC map during the delay period. Imaging revealed metastatic liver cancer, and the patient underwent a partial hepatectomy. However, the final histopathological diagnosis was RLH. CONCLUSION: If small isolated nodules are found in the liver of middle-aged and elderly female patients with no risk factors for liver malignancy, when the enhanced imaging suggests "wash-in and wash-out", further focus should be placed on whether the enhanced imaging shows perinodular enhancement and whether the DWI shows limited diffusion in MRI, in order to emphasize the possibility of liver RLH diagnosis.

Lymphoma and Other Lymph Node Pathologies Among Adult Patients with Lymphadenopathy in Abakaliki, Nigeria.

INTRODUCTION: Lymphadenopathy is usually due to benign or malignant conditions. It can also be local or systemic in distribution and can involve peripheral or deep-seated lymph nodes. This study aimed to determine the prevalence of lymphoma and the distribution pattern of lymph node pathologies among adult patients who presented with lymphadenopathy and its relationship with age and sex. METHODS: A retrospective study was conducted, and a record of all cases of lymphadenopathy with histological diagnosis over 5-year period (January 2017 to December 2021) was extracted from Departments of Anatomical Pathology of Alex Ekwueme Federal University Teaching Hospital, Abakaliki. The data generated were analyzed using Statistical Package for Social Sciences (SPSS) software, version 26. RESULTS: One hundred and ninety results were extracted with an age range of 18 to 94 years and a mean age of 41 ± 16 years. They were made up of 75 (39.5%) males and 115 (60.5%) females, with a male-to-female ratio of 1:1.5. The prevalence of lymphoma was 50.0% (95/190). Thirty-five (18.4%) were Hodgkin's lymphoma (HL), while 60 (31.6%) were non-Hodgkin's lymphoma (NHL). Other pathologies manifested by cases of lymphadenopathy include metastatic tumor deposits (38 (20%)), reactive lymphoid hyperplasia (29 (15.3%)), and tuberculous lymphadenitis (18 (9.5%)). Others include sinus histiocytosis (4 (2.1%)), dermatopathic lymphadenitis (5 (2.6%)), and Castleman's disease (1 (0.5%)). CONCLUSION: About half of all patients who presented with lymphadenopathy were lymphoma with a high prevalence of 50%, and the majority were NHL. Other major causes of lymphadenopathy were metastatic tumor deposits, reactive lymphoid hyperplasia, and tuberculous lymphadenitis. Any case of lymphadenopathy should be properly investigated early for effective management.

Decrease of 5-hydroxymethylcytosine in primary cutaneous CD4+ small/medium sized pleomorphic T-cell lymphoproliferative disorder.

BACKGROUND: Primary cutaneous CD4+ small/medium-sized pleomorphic T-Cell lymphoproliferative disorder (PC-SMTLD) has been considered as a controversial dermatological disease that has been included in cutaneous T-cell lymphoma group, presenting most commonly as a solitary nodule and/or plaque with a specific and characteristic head and neck predilection. Due to the considerable overlap between PC-SMTLD and pseudolymphoma (PL), the differential diagnosis is often challenging. Methylation of DNA at position 5 of cytosine, and the subsequent reduction in intracellular 5-hydroxymethylcytosine (5-hmC) levels, is a key epigenetic event in several cancers, including systemic lymphomas. However, it has rarely been studied in cutaneous lymphomas. OBJECTIVES: The authors aimed to explore the role of differential 5-hmC immunostaining as a useful marker to distinguish PC-SMTLD from PL. METHODS: Retrospective case series study with immunohistochemical and immunofluorescence analysis of 5-hmC was performed in PL and PC-SMTLD. RESULTS: Significant decrease of 5-hmC nuclear staining was observed in PC-SMTLD when compared with PL (p < 0.0001). By semi-quantitative grade integration, there were statistical differences in the final 5-hmC scores in the two study groups. The IF co-staining of 5-hmC with CD4 revealed a decrease of 5-hmC in CD4+ lymphocytes of PC-SMTLD. STUDY LIMITATIONS: The small clinical sample size of the study. CONCLUSIONS: The immunorreactivity of 5-hmC in CD4+ lymphocytes was highly suggestive of a benign process as PL. Furthermore, the decrease of 5-hmC nuclear staining in PC-SMTLD indicated its lymphoproliferative status and helped to make the differential diagnosis with PL.

Hepatic reactive lymphoid hyperplasia-associated primary biliary cholangitis masquerading as a neoplastic liver lesion.

Hepatic reactive lymphoid hyperplasia is an uncommon benign condition, often found incidentally as a solitary liver lesion. The chronic inflammatory reaction associated with autoimmune conditions and malignancies has been postulated as a possible aetiology. The diagnosis is challenging as it often mimics various malignancies radiologically and histologically, hence the diagnosis being made only after surgical resection. Lymphadenopathy is common with primary biliary cholangitis, though rarely reported with reactive lymphoid hyperplasia. We report a case of hepatic reactive lymphoid hyperplasia associated with portacaval lymphadenopathy in a patient with primary biliary cholangitis, diagnosed after surgical resection. We propose lesional biopsy be considered in patients with primary biliary cholangitis found to have a solitary lesion with supporting low-risk clinical and radiological features.

Adolescence Pseudolymphoma / Pseudolinfoma na adolescência

Objective: report an uncommon case of cutaneous pseudolymphoma in teenage years, undiagnosed for approximately 8 years old. Methodology: data were taken from medical records, patient interviews, photographic records of the injuries, diagnostic methods, and literature review. The paper was subjected and approved by the Research Ethics Committee (REC), under the number 4.952.193, authorized by the patient and their legal sponsor. Final Conclusions: the related case shows the importance of reliable and differential diagnoses since the patient carried the injury through approximately eight years without getting any diagnosis and/or treatment. Furthermore, the unusual age and the location of the injuries make the information presented here fundamental to helping other professionals and contributing to the Public Health System (AU).

Objetivo: Relatar um caso incomum de Pseudolinfoma Cutâneo na adolescência, não diagnosticado por aproximadamente oito anos. Método: As informações foram obtidas pela revisão do prontuário, entrevista com o paciente, registro fotográfico das lesões e dos métodos diagnósticos e revisão de literatura. O trabalho foi submetido e aprovado pelo Comitê de Ética em Pesquisa (CEP), número de aprovação 4.952.193, com autorização do paciente e seus responsáveis legais. Considerações Finais: o caso relatado evidencia a importância de um diagnóstico fidedigno e dos diagnósticos diferenciais, uma vez que a paciente apresentou a lesão por aproximadamente oito anos, sem receber nenhum diagnóstico e/ou tratamento. Além disso, não só a faixa etária é incomum, mas também a localização da lesão e por esta razão, as informações são fundamentais para auxiliar outros profissionais, com benefício deste estudo para o Sistema de Saúde (AU).

A case of hepatic reactive lymphoid hyperplasia: the review of 23 cases from the literatures.

A 70-year-old woman was referred to our hospital because of slight elevation of soluble interleukin-2 receptor (sIL-2R) and accumulation of 18F-fluorodeoxyglucose (FDG) in S8 of the liver on positron emission tomography. The mass was strongly suspected to be malignant because of contrast enhancement and enlargement in size of the mass, and suspicion of portal vein invasion. Hepatic S8 subsegmentectomy was performed for diagnostic and therapeutic purposes. Hematoxylin and eosin staining of the resected specimen showed small lymphocytes with no atypia and no formation of lymphoid follicles. Immunostaining showed CD3-positive cells in the interfollicular region and CD20-positive cells in the lymphoid follicles. Both CD10 and BCL-2 were negative in the follicular germinal center. CD138-positive plasma cells were observed and there was no light chain restriction. Based on polyclonal growth pattern of lymphocytes in the lymphoid follicles and interfollicular region, she was diagnosed with hepatic reactive lymphoid hyperplasia (RLH).Review of the English literature of hepatic RLH which referred to imaging findings yielded 23 cases, including this case. As a result, we suggest that liver biopsy should be performed for definitive diagnosis, when hepatic RLH is suspected by imaging findings and backgrounds.

Multippel erythema migrans, borrelialymfocytom og nevroborreliose hos eit barn.

BACKGROUND: Lyme disease after a tick bite often presents as erythema migrans, yet less frequent variants of this disease, such as Borrelia lymphocytoma, multiple erythema migrans and neuroborreliosis, are also seen occasionally. CASE PRESENTATION: We report a case of a tick-bitten child who first presented with an indistinct macular erythema around the left eye and a more distinct macular erythema on and around the left ear. The next day, she developed a facial palsy. INTERPRETATION: The case was interpreted as facial multiple erythema migrans and Borrelia lymphocytoma on the ear, followed by neuroborreliosis. The diagnosis of lymphocytoma was made from clinical findings and PCR of skin biopsy. She recovered quickly after intravenous ceftriaxone and is now healthy.

Iron induces B cell pyroptosis through Tom20-Bax-caspase-gasdermin E signaling to promote inflammation post-spinal cord injury.

BACKGROUND: Immune inflammatory responses play an important role in spinal cord injury (SCI); however, the beneficial and detrimental effects remain controversial. Many studies have described the role of neutrophils, macrophages, and T lymphocytes in immune inflammatory responses after SCI, although little is known about the role of B lymphocytes, and immunosuppression can easily occur after SCI. METHODS: A mouse model of SCI was established, and HE staining and Nissl staining were performed to observe the pathological changes. The size and morphology of the spleen were examined, and the effects of SCI on spleen function and B cell levels were detected by flow cytometry and ELISA. To explore the specific mechanism of immunosuppression after SCI, B cells from the spleens of SCI model mice were isolated using magnetic beads and analyzed by 4D label-free quantitative proteomics. The level of inflammatory cytokines and iron ions were measured, and the expression of proteins related to the Tom20 pathway was quantified by western blotting. To clarify the relationship between iron ions and B cell pyroptosis after SCI, we used FeSO4 and CCCP, which induce oxidative stress to stimulate SCI, to interfere with B cell processes. siRNA transfection to knock down Tom20 (Tom20-KD) in B cells and human B lymphocytoma cell was used to verify the key role of Tom20. To further explore the effect of iron ions on SCI, we used deferoxamine (DFO) and iron dextran (ID) to interfere with SCI processes in mice. The level of iron ions in splenic B cells and the expression of proteins related to the Tom20-Bax-caspase-gasdermin E (GSDME) pathway were analyzed. RESULTS: SCI could damage spleen function and lead to a decrease in B cell levels; SCI upregulated the expression of Tom20 protein in the mitochondria of B cells; SCI could regulate the concentration of iron ions and activate the Tom20-Bax-caspase-GSDME pathway to induce B cell pyroptosis. Iron ions aggravated CCCP-induced B cell pyroptosis and human B lymphocytoma pyroptosis by activating the Tom20-Bax-caspase-GSDME pathway. DFO could reduce inflammation and promote repair after SCI by inhibiting Tom20-Bax-caspase-GSDME-induced B cell pyroptosis. CONCLUSIONS: Iron overload activates the Tom20-Bax-caspase-GSDME pathway after SCI, induces B cell pyroptosis, promotes inflammation, and aggravates the changes caused by SCI. This may represent a novel mechanism through which the immune inflammatory response is induced after SCI and may provide a new key target for the treatment of SCI.