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.

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.

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.

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.

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.

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.

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.

Jessner's Lymphocytic Infiltration of the Skin in a 73-Year-Old Woman: A Case Report.

BACKGROUND Jessner's lymphocytic infiltration of the skin (JLIS) is a rare and benign process of unknown cause. This disorder affects both sexes, most commonly in the young adult population. However, the demographic characteristics remain largely unknown, due to limited information. JLIS clinical presentation is heterogeneous; lesions can be indurated papular or erythematous plaques on the upper body. Symptoms are variable, from asymptomatic to pruritus and burning sensation. CASE REPORT A female patient aged 73 years presented with 10-day asymptomatic dermatosis on the left malar area after an insect sting. At the beginning, the lesion was clinically classified as an abscess and antibiotic therapy was prescribed with ciprofloxacin 500 mg every 12 hours for 5 days. However, due to the lack of clinical response, a biopsy was performed, which reported a predominantly lymphocytic nodular dermatitis. JLIS diagnosis was confirmed after laboratory and imaging tests. Intralesional infiltrations of triamcinolone (0.5 ml) twice within 15 days and mineral sunscreen 3 times a day were prescribed. After the treatment, the lesion had a complete resolution without recurrence to date. CONCLUSIONS The present case reports JLIS in an older woman who presented a complete healing resolution of the lesion without recurrences after triamcinolone intralesional infiltrations and sunscreen protection.

Pseudolymphoma to Lymphoma: A Case of Chronic Reactive Lymphoid Hyperplasia Transforming to Primary Cutaneous Marginal Zone Lymphoma.

ABSTRACT: Primary cutaneous marginal zone lymphoma (PCMZL) is a low-grade malignant B-cell lymphoma that originates from the skin. It often presents as erythematous solitary or multiple papules, nodules, and/or plaques. It is one of the 3 main subtypes of primary cutaneous B-cell lymphomas. PCMZLs are believed to develop from chronic antigenic stimulation such as from tick-borne bacteria, vaccines, tattoo pigment, or other foreign body. In addition, cutaneous lymphoid hyperplasia, a documented precursor to malignant PCMZL, often presents in response to areas of chronic inflammation. Cutaneous lymphoid hyperplasia and PCMZL share several clinical and histological similarities that require clinicopathologic suspicion, immunohistochemical ancillary studies, and histopathologic analysis to accurately differentiate the 2 entities. Although gene rearrangement studies have historically been of limited value in the diagnosis of PCMZL, recent studies investigating molecular markers have identified the presence of multiple genetic abnormalities that have helped to better characterize the disease and aid in diagnosis. In addition, newer studies have found associations between PCMZL and gastrointestinal disorders, including Helicobacter pylori and inflammatory bowel disorders. In this article, we describe a case of a 56-year-old patient with a history of ulcerative colitis presenting with chronic reactive lymphoid hyperplasia that transformed to primary cutaneous marginal zone lymphoma.

Clinical features, natural history and outcomes of pseudolymphoma of liver: A case-series and systematic review.

BACKGROUND: Pseudolymphoma is a rare, benign, nonspecific condition that forms a mass-like lesion characterized by the proliferation of non-neoplastic lymphocytes. Lacking of specific clinical symptoms, serological markers, and imaging features, the diagnosis is difficult. We reporte five cases of hepatic pseudolymphoma and provide a systematic review of existing literatures to improve our understanding of this rare liver disease. METHODS: We followed-up five cases of hepatic pseudolymphoma in West China Hospital from January 2002 to January 2022. We also summarized the cases of hepatic pseudolymphoma from January 1981 to December 2021 through the PubMed database and comprehensively analyzed the characteristics of the cases. RESULTS: The pathologic features of the five cases were characterized by benign lymphoid tissue hyperplasia, lymphoid follicle formation, and a polarized germinal center. Immunohistochemistry, in situ hybridization, and gene rearrangement revealed non-malignant lymphoma. Besides, a total of 116 cases have been reported in the PubMed database from 1981 to 2021. The incidence of hepatic pseudolymphoma is higher in middle-aged and elderly women and has been reported more frequently in Asia. All cases were pathologically diagnosed, among which 85.95% of the patients were treated by surgery. CONCLUSIONS: Hepatic pseudolymphoma is an extremely rare benign disease, mainly in middle-aged and elderly women. Without distinctive clinical and imaging characteristics, pathological diagnosis is the highly reliable method at present. Thus, in the absence of risk factors for a primary liver tumor or metastatic tumor in middle-aged and elderly women, the possibility of pseudolymphoma should be considered to avoid extensive treatments.

A case of multiple nodular cutaneous B-cell pseudolymphoma successfully treated with glucocorticoid, methotrexate, and hydroxychloroquine.

Cutaneous pseudolymphomas (CPL) is a group of benign, reactive, and polyclonal lymphoproliferative dermatoses that simulate cutaneous lymphomas (CL) clinically and histologically. Based on the predominating component of lymphocytic infiltrate, CPL can be divided into cutaneous B-cell pseudolymphomas (CBPL), cutaneous T-cell pseudolymphomas (CTPL), mixed (T-/B-cell) pseudolymphomas, CD30-positive pseudolymphomas, and non-classifiable pseudolymphomas. Most patients with localized nodular CBPL present with a solitary nodule. However, few patients develop multiple skin lesions, rarely in generalized forms. Here we describe a rare case of multiple nodular CBPL on both sides of the patient's neck, which was treated successfully with intramuscular injection of compound betamethasone, oral methotrexate, and hydroxychloroquine for 4 months. No recurrence was observed in the patient at the one-year follow-up. This combined treatment may be a promising treatment choice for multiple nodular CBPL.

[The clinicopathological features of adult orbital xanthogranulomatous disease with lacrimal gland reactive lymphoid hyperplasia].

Objective: To investigate the clinicopathological features of adult orbital xanthogranulomatous disease (AOXGD) with lacrimal gland reactive lymphoid hyperplasia. Methods: Retrospective case series study. The clinical and pathological data of AOXGD cases diagnosed and treated in Tianjin Eye Hospital from January 2002 to December 2021 was reviewed, and the clinical characteristics, radiologic findings and pathological characteristics of periocular and lacrimal gland lesions of 5 cases were retrospectively analyzed. The expression of IgG4 and IgG protein in periocular and lacrimal gland lesions was detected by immunohistochemical staining, and the role of IgG4 in AOXGD was preliminarily studied. Results: There were four females and one male with an average age of 53.8 years (39 to 77 years). Among the five AOXGD cases, there were three cases of adult-onset xanthogranuloma, one case of adult-onset asthma and periocular xanthogranuloma, and one case of necrobiotic xanthogranuloma. All cases involved both eyes. The swelling of eyelids was observed in five cases, and the yellow or pale yellow eyelid skin was found in two cases. Imaging examinations showed the tumor mainly involved the eyelids, subcutaneous tissues, anterior orbit and lacrimal gland. A large number of foam cells and typical Touton giant cells were found in the periorbital lesions, accompanied by different degrees of fibrosis. The fibrinoid necrosis was detected in one case of necrobiotic xanthogranuloma. The lacrimal gland lesions showed different types of reactive lymphoid hyperplasia, including IgG4-related disease in two cases, follicular lymphoid hyperplasia in two cases and focal lymphoid hyperplasia in one case. IgG4 levels of periorbital and lacrimal gland lesions were elevated in four cases. Asthma and elevated serum IgG4 were found in one case of adult-onset periocular xanthogranuloma. Three patients underwent surgical resection and adjuvant hormone or immunosuppressive therapy, and two patients underwent simple surgical resection. The patients were followed up for 1.5 to 10.0 years, one patient was lost, and four patients had no recurrence. Conclusions: AOXGD with lacrimal gland reactive lymphoid hyperplasia is a group of rare diseases. The periorbital lesions of that are characterized by proliferation of foamy histiocytes and Touton giant cells, and the lacrimal gland lesions of that manifest as IgG4-related disease in some cases.

Cutaneous reactive B-cell lymphoid proliferations.

Cutaneous lymphoid hyperplasia (CLH), also known as cutaneous pseudolymphoma, is a spectrum of benign conditions characterized by reactive B- and T-cell cutaneous lymphocytic infiltrates. B-cell lymphoid proliferations are a heterogenous group of non-neoplastic cutaneous diseases that must be histopathologically distinguished from cutaneous B-cell lymphomas. These proliferations can be observed as reactive phenomena to infections, medications, allergens, neoplasms, and more. Furthermore, there are many inflammatory conditions that present with reactive B-cell infiltrates, including actinic prurigo, Zoon balanitis, Rosai-Dorfman disease, and cutaneous plasmacytosis. This review summarizes multiple cutaneous B-cell lymphoid proliferations within the major categories of reactive and disease-associated CLH. Further we discuss major discriminating features of atypical CLH and malignancy. Understanding the specific patterns of B-cell CLH is essential for the proper diagnosis and treatment of patients presenting with such lesions.