MALT Lymphoma in Children: Case Report and Review of the Literature

Primary giant mucosa-associated lymphoid tissue lymphoma of the lower lip: a case report and literature review

Oral lymphomas are rare and difficult to diagnose, with Mucosa-Associated Lymphoid Tissue (MALT) lymphoma most commonly affecting older adults, particularly women. MALT lymphoma of the lip is exceptionally rare, and its cause is poorly understood. We present a case of primary giant MALT lymphoma of the lower lip, explore its clinicopathological features, and review relevant literature. An 83-year-old woman developed a painless, pea-sized swelling on the right lower lip over three years, which gradually increased in size without discomfort. She had no history of chronic infections or autoimmune diseases, and all investigations were unremarkable. Examination revealed a spherical, indurated mass on the left lower lip, measuring 8 cm, with no regional lymphadenopathy. Histology and immunohistochemistry confirmed extranodal marginal zone B-cell lymphoma of MALT. This case underscores the need to consider lymphoma in the differential diagnosis, even without systemic symptoms. Patients with oral MALT lymphoma often achieve complete remission after treatment, but diagnosing it can be challenging, requiring immunohistochemical testing for confirmation.

Helicobacter pylori-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphoma in a Girl

Introduction

Extranodal marginal zone lymphoma (MZL) arises in a number of epithelial tissues, including the stomach, salivary gland, lung, small bowel, thyroid, ocular adnexa, skin, and elsewhere. It has also been called low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). MALT lymphoma predominantly occurs in adults and is rare in children.

Case Presentation

We report a case of MALT lymphoma involving the stomach, which is the most common subtype, in a 12-year-old girl. Initially, the patient relapsed after antibiotic therapy but achieved successful treatment subsequently through irradiation.

Conclusion

Helicobacter pylori eradication therapy should be given to all patients with gastric MZL, irrespective of stage. In patients who do not respond to antibiotic therapy, treatment options such as irradiation and systemic cancer therapies should be considered, depending on the disease stage.

Primary appendiceal MALT lymphoma clinically masquerading as chronic appendicitis: A case report

INTRODUCTION AND IMPORTANCE

Mucosal associated lymphoid tissue (MALT) lymphomas are a type of extranodal indolent lymphoma. They appear in areas ordinarily devoid of lymphoid tissues and are frequently preceded by chronic antigenic stimulation. Primary MALT lymphoma is an extremely rare variant in the appendix.

CASE PRESENTATION

A 22-year-old man presented with recurrent abdominal pain of three months. CT scan of the abdomen showed appendiceal wall thickening with ileo-colic lymphadenopathy. The patient was managed with right hemicolectomy and the histopathological examination showed MALT lymphoma.

CLINICAL DISCUSSION

MALT lymphomas of the appendix are extremely rare. Chronic appendicitis is an uncommon but possible clinical presentation. Although imaging techniques are essential for making a diagnosis, histological analysis is what leads to a final diagnosis. While there are no specific recommendations for treating appendiceal MALTomas, prior case reports indicate that appendectomy and surveillance may be sufficient.

CONCLUSION

Primary MALT lymphoma is extremely uncommon in the appendix. It is indolent in nature and can manifest clinically as chronic appendicitis. The management for localized disease is surgery or radiotherapy. The prognosis is excellent regardless of the initial treatment modality.

Diagnosis and management of rare paediatric Non-Hodgkin lymphoma

Mature B-cell lymphomas, (B- or T-cell) lymphoblastic lymphomas (LBL), and anaplastic large cell lymphoma (ALCL) correspond to about 90% of all non-Hodgkin lymphoma (NHL) cases occurring in children and adolescents. The remaining 10% encompass a complex group of entities characterized by low/very low incidences, paucity of knowledge in terms of underlying biology in comparison to their adult counterparts, and consequent lack of standardization of care, information on clinical therapeutic efficacy and long-term survival. At the Seventh International Symposium on Childhood, Adolescent and Young Adult NHL, organized on October 20-23, 2022, in New York City, New York, US, we had the opportunity to discuss clinical, pathogenetic, diagnostic, and treatment aspects of certain subtypes of rare B- or T-cell NHL and they will be the topic of this review.

Primary oral mucosa-associated lymphoid tissue (MALT) lymphoma in patient with monoclonale gammopathy: a rare case report

Background

Monoclonal gammopathy is a biological reality encountered in approximately 1% of the general population. In the absence of clinical and biological signs, it is considered of undetermined significance; however, it can be a biological signature of a monoclonal lymphocytic or plasma-cell proliferation. Their localisation to the oral mucosa remains rare and difficult to diagnose, particularly in indolent forms that escape imaging techniques.

Case presentation

Here, we report the case of a 73-year-old woman with a history of IgM kappa gammopathy followed for 13 years. The patient did not have a chronic infection or an autoimmune disease, and all the biological investigations and radiological explorations were unremarkable during this period. The discovery of a submucosal nodule in the cheek led to the diagnosis of MALT lymphoma and regression of half of the IgM kappa level after resection. The review of the literature shows the dominance of clinical signs (i.e., a mass or swelling) in the diagnosis of primary MALT lymphomas of the oral cavity after surgical resection.

Conclusions

Our case illustrates the role of examination of the oral cavity in the context of a monoclonal gammopathy. The absence of clinical and radiological evidence in favor of lymphoplasmacytic proliferation, does not exclude a primary indolent MALT lymphoma of the oral mucosa.

Pediatric hematolymphoid pathology in the gastrointestinal tract

Hematolymphoid processes involving the gastrointestinal tract in the pediatric and adolescent young adult (AYA) populations include processes occurring primarily within the gastrointestinal tract as well as systemic diseases with predilection for gastrointestinal involvement. Here, we present a focused review of reactive and neoplastic entities occurring in the pediatric and AYA age groups.

MALT lymphoma and eosinophilic oesophagitis: incidental finding- review of possible factors influencing the aetiopathogenesis of eosinophilic oesophagitis

An 11-year-old boy with a history of atopy and allergic rhinitis under treatment with sublingual immunotherapy was referred following several episodes of food impaction. Diagnosis of eosinophilic oesophagitis, chronic gastritis and gastric mucosa-associated lymphoid tissue (MALT) lymphoma associated to Helicobacter pylori were confirmed. Results of the extension study were negative and the lymphoma was resolved with eradicating treatment for H. pylori No improvement was observed in the oesophagitis after the withdrawal of immunotherapy and treatment with high proton pump inhibitor doses or following the omission of several foods to which subclinical sensitisation was confirmed. Oesophagitis was finally resolved by removing cow's milk protein. After 10 years, neither eosinophilic oesophagitis nor MALT lymphoma was observed.Gastric MALT lymphoma associated to H. pylori is a rare disorder in children. Although coexisting H. pylori infection is common in patients with eosinophilic oesophagitis, the association of gastric MALT lymphoma with eosinophilic oesophagitis has not been reported before.

Rare non-Hodgkin lymphoma of childhood and adolescence: A consensus diagnostic and therapeutic approach to pediatric-type follicular lymphoma, marginal zone lymphoma, and nonanaplastic peripheral T-cell lymphoma

Pediatric-type follicular (PTFL), marginal zone (MZL), and peripheral T-cell lymphoma (PTCL) account each for <2% of childhood non-Hodgkin lymphoma. We present clinical and histopathological features of PTFL, MZL, and few subtypes of PTCL and provide treatment recommendations. For localized PTFL and MZL, watchful waiting after complete resection is the therapy of choice. For PTCL, therapy is subtype-dependent and ranges from a block-like anaplastic large cell lymphoma (ALCL)-derived and, alternatively, leukemia-derived therapy in PTCL not otherwise specified and subcutaneous panniculitis-like T-cell lymphoma to a block-like mature B-NHL-derived or, preferentially, ALCL-derived treatment followed by hematopoietic stem cell transplantation in first remission in hepatosplenic and angioimmunoblastic T-cell lymphoma.

Extranodal Marginal Zone B-Cell Lymphoma/Maltoma of the Lip in a Child

All forms of cutaneous lymphomas are rare in children. Extranodal marginal zone B-cell lymphomas (EMZBL)/mucosa-associated lymphoid tissue (MALT) lymphomas are unusual neoplasms in children and young adults. We report a case of an EMZBL/MALT lymphoma of the lip in a previously healthy 14-year-old boy without immunodeficiency, confirmed by immunohistochemistry and documentation of clonal rearrangement of the immunoglobulin heavy-chain gene. Additionally, we present a review of the differential diagnosis of skin and mucosal lymphoid proliferations in childhood.

Rare Posterior Pharyngeal Mass: Atypical Marginal Zone Hyperplasia

Cases of posterior pharyngeal masses are quite rare, and are typically derived from schwannoma or encephalocele, or are of vascular or infectious origin. They are clinically significant due to their tendency to cause airway obstruction. The aim of this study was to present a rare atypical marginal hyperplasia case of a posterior pharyngeal wall mass. A 10-year-old male was admitted to our clinic with dyspnea. A plane-surfaced 4 × 3 × 3 cm mass was observed on the posterior pharyngeal wall upon physical examination. The patient underwent magnetic resonance imaging and surgical treatment. Following excision of material from the patient's mass, a pathologic diagnosis of atypical marginal zone hyperplasia was made. Atypical marginal zone hyperplasia of the posterior pharyngeal wall has not yet been reported in the literature. Marginal zone hyperplasia associated with a lymphoproliferative disease should be considered when making differential diagnoses of posterior pharyngeal wall masses.

Pediatric Pharyngeal IgD-positive Monoclonal Plasmacytoid and Plasma Cell Neoplasm

Pediatric neoplasm with monoclonal proliferation of lymphoplasmacytoid lymphocytes and plasma cells is exceedingly rare and has essentially never been reported in immunocompetent children. Here, we report a previously healthy 13-year-old girl with a pharyngeal mass and enlarged cervical lymph nodes. The pharyngeal mass was composed of CD138, CD79a, MUM-1, IgD, CD20, PAX-5, CD43, λ-restricted monoclonal plasmacytoid, and plasma cells. Scattered CD20, PAX-5 B cells were present in the background. The patient was treated as localized non-Hodgkin lymphoma (stage II) with cyclophosphamide, doxorubicin, vincristine, and prednisone and is in complete remission at 17 months from the last chemotherapy.

Atypical Marginal Zone Hyperplasia Is a Mimic for Lymphoma in Pediatric Transplant Recipients: Report of Two Patients

Atypical marginal zone hyperplasia (AMZH) of mucosa-associated lymphoid tissue (MALT) closely resembles lymphoma in that it shows expansion of the marginal zones with prominent intraepithelial B lymphocytes, is immunoglobulin light-chain restricted, and may show aberrant CD43 expression. However, unlike lymphoma, it does not show rearrangement of the immunoglobulin heavy chain gene (immunoglobulin H [IgH]) by polymerase chain reaction (PCR), and it behaves in a benign fashion. We identified AMZH in 2 pediatric solid organ transplant recipients who presented with adenotonsillar hypertrophy. To date, the patients have experienced a self-limited course in the absence of treatment or reduction of immunosuppression. Atypical marginal zone hyperplasia is a pitfall for posttransplant lymphoproliferative disorder and MALT lymphoma in the pediatric solid organ transplant population. In transplant patients with a lambda-restricted B-cell clone and marginal zone hyperplasia in native MALT sites, PCR for IgH and IgK gene rearrangement is essential to prevent misdiagnosis.

Uncommon non-Hodgkin lymphomas of childhood: pathological diagnosis, clinical features and treatment approaches

We provide a review of the pathological and clinical features for uncommon B-cell and T-cell lymphomas of childhood with a specific focus on advances in treatment approaches and outcomes. There is clearly a need for prospective investigation of both the clinical and biological features of the uncommon non-Hodgkin lymphoma subtypes in childhood. These results should lead to more uniform and more effective treatment approaches.

Steroid-responsive atypical marginal zone hyperplasia of the lip in a child

Atypical marginal zone hyperplasia (AMZH) is a recently described disease entity seen mainly in children. AMZH most commonly affects tonsils and appendices. Cutaneous AMZH is rare. The authors report here a recurrent AMZH in the lip of a 9-year-old child who presented originally with a lip swelling for approximately 3 months. The lip lesion recurred after each incomplete excision for 4 times. Pathologically, the lesion demonstrated marginal zone B-cell hyperplasia with kappa monoclonality by flow cytometry and immunohistochemistry studies. Lymphoepithelial lesions were noted with involvement of minor salivary glands. Polymerase chain reaction for immunoglobulin heavy-chain gene rearrangement has been repeatedly negative. Polymerase chain reaction for Borrelia species DNA was negative on both paraffin-embedded tissue and plasma. Serum antibodies IgG and IgM for Helicobacter Pylori were positive. A diagnosis of AMZH was made. Two courses of anti H. Pylori therapy did not improve the lip lesion, which completely regressed after a course of prednisone therapy. With differential diagnosis of cutaneous marginal zone lymphoma, the case illustrated diagnostic challenges, especially with recurrent lesions. This is the first case of recurrent cutaneous AMZH that has uncharacteristic kappa light-chain restriction. AMZH should be considered in children with mucocutaneous lesions with features of marginal zone lymphoma.

Epstein-barr virus-associated extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT Lymphoma) arising in the parotid gland of a child with ataxia telangiectasia

Hematologic malignancies, in particular T-cell lymphomas/leukemias, are prevalent in patients with ataxia telangiectasia (AT), with most reported cases being clinically aggressive and high grade. Epstein-Barr virus (EBV) is often associated with lymphoid proliferations/neoplasms arising in immunodeficient patients. Reports of low-grade B-cell neoplasms in the ataxia telangiectasia population are extremely rare. Here, we describe a case of EBV-associated extranodal marginal zone lymphoma (mucosa-associated lymphoid tissue lymphoma) of the parotid gland in a 16-year-old boy with AT. In addition, we review the literature of hematologic malignancies in the AT population as well as the occurrence of EBV in mucosa-associated lymphoid tissue lymphoma.

Endoscopic and histologic analysis of gastric mucosa-associated lymphoid tissue in children with Helicobacter pylori infection

OBJECTIVES

Nodular gastritis (NG) associated with Helicobacter pylori infection can occur commonly in childhood and is regarded to be benign without clinical significance. This study includes endoscopic and histologic analysis of gastric mucosa-associated lymphoid tissue (MALT) to clarify the significance of NG on endoscopy in H pylori-infected children.

METHODS

Of the 758 children who underwent endoscopy, 80 were identified as having H pylori infection. These patients were divided into 3 groups based on endoscopic severity of gastric nodularity. Histopathologic grading of MALT and immunohistochemistry of CD3, CD20, cytokeratin, and Ki-67 were evaluated.

RESULTS

On endoscopy, severe NG was observed in the antrum of 38 of the 80 subjects, mild NG in 27, and an absence of NG in 15. Density of H pylori and lymphocyte infiltration differed among the 3 groups (P=0.022 and P=0.025, respectively). Histological grading for gastric lymphoid infiltrates was compatible with grade 1 in 47 (58.8%), grade 2 in 21 (26.3%), grade 3 in 7 (8.8%), and grade 4-5 in 4 (5.1%) in the antrum. Degree of NG, density of H pylori, neutrophil activity, and gastritis score in the antrum varied with MALT grades (P=0.003, P=0.042, P=0.028, and P=0.006, respectively).

CONCLUSIONS

Our study suggests NG may present as a significant gastric manifestation of childhood H pylori infection that indicates gastric MALT. Thorough histologic investigation may be useful in the evaluation of gastric MALT in children infected with H pylori that manifests as severe NG in the antrum.

Pediatric extranodal marginal zone B-cell lymphoma presenting as amyloidosis in minor salivary glands: a case report and review of the literature

We report an unusual case of an extranodal marginal zone B-cell lymphoma (EMZL) arising in the labial minor salivary gland in an immunocompetent 11-year-old boy. The initial histopathologic review favored localized amyloidosis. However, further evaluation supported the diagnosis of low-grade B-cell lymphoma with plasmacytic differentiation, surrounded by deposits of AL κ-type amyloid. Clinical management consisted of excision with no recurrence at 1-year follow-up. This case demonstrates that a diagnosis of lymphoma must be considered in cases of amyloidosis associated with minor salivary gland involvement, even in children. In addition, we provide a literature review of extranodal marginal zone B-cell lymphoma arising in salivary glands.

Thymic mucosa-associated lymphoid tissue lymphoma in an adolescent girl

Mucosa-associated lymphoid tissue (MALT) lymphoma is very rare in children. We report the first case of pediatric thymic MALT lymphoma in an adolescent Asian girl. She presented with chest pain, dyspnea, and low-grade fever. A large anterior mediastinal mass was biopsied that confirmed the diagnosis of MALT lymphoma with trisomy 18. The patient had secondary immunodeficiency with low NK cell count and high IgA and IgG levels. Because of the advanced stage and the presence of trisomy 18, she was treated with cyclophosphamide, vincristine, prednisone, and rituximab, followed by involved-field radiotherapy. She is currently undergoing maintenance therapy with rituximab and remains in complete remission at 13 months from diagnosis. Thymic MALT lymphoma should be suspected in any Asian child with a cystic thymic mass and autoimmune disease or hyperglobinemia. Because of the slow proliferation rate of this type of lymphoma, a long-term follow-up is needed.

Mucosa-associated lymphatic tissue lymphoma of the lower lip in a child

Mucosa-associated lymphatic tissue lymphoma of the lip in a child is a very rare clinical entity whose cause is poorly understood. We describe an 11-year-old boy who presented with a 5-month history of an asymptomatic nodule on the lower lip with the clinical appearance of a benign mucocele. After surgical excision of the lower lip lesion, lymphocyte phenotypic analysis and histologic examination of the specimen disclosed an extranodal marginal zone B-cell lymphoma of mucosa-associated lymphatic tissue type of the buccal minor salivary glands. Mucosa-associated lymphatic tissue lymphoma of the lip may clinically resemble a large mucocele. To prevent a delayed detection of lip mucosa-associated lymphatic tissue lymphoma, an incisional biopsy of large mucous cysts of the oral mucosa before marsupialization is recommended.

[Salivary gland tumors in children]

Salivary gland tumors in children are rare: they correspond to 8-10% of head and neck pediatric tumors. Clinicians of all disciplines should be aware of this diagnosis in front of non-inflammatory mass of the parotid or in the territory of other salivary glands. In children, 50% of salivary gland tumors are malignant which contrasts with a 10-25% risk in adults. Epithelial tumors are the most common, mucoepidermoïd carcinomas of the parotid in particular. Surgery is the treatment of choice in epithelial tumors. Adjuvant radiotherapy may be indicated in case of unfavorable prognostic factors but must be balanced with the risk of radiation-induced growth defects and secondary cancer. The role of chemotherapy is limited in these tumors, but should be discussed in case of an inoperable or metastatic lesion.

Mucosa-Associated Lymphoid Tissue Lymphoma of the Lacrimal Gland: Sustained Remission after Eradication of Helicobacter Pylori Infection

Mucosa-associated lymphoid tissue (MALT) lymphoma is the third most common non-Hodgkin lymphoma, and it is strongly associated with helicobacter pylori infection of the stomach. MALT lymphoma of the lacrimal gland usually presents as a localized disease process in extranodal tissues. The treatment options of MALT lymphoma of the lacrimal gland chiefly include radiation of the tumor, chemotherapy, surgical removal, or a combination of these strategies. We report a case of localized MALT lymphoma of the lacrimal gland, with prolonged sustained remission after eradication of gastric Helicobacter pylori (H. Pylori) infection. He sustains in remission of lacrimal MALT lymphoma for four years without chemotherapy or radiotherapy.

Pediatric lymphomas in Brazil

OBJECTIVE

This study provides the clinical pathological characteristics of 1301 cases of pediatric/adolescent lymphomas in patients from different geographic regions of Brazil.

METHODS

A retrospective analyses of diagnosed pediatric lymphoma cases in a 10-year period was performed. We believe that it represents the largest series of pediatric lymphomas presented from Brazil.

RESULTS

Non-Hodgkin lymphomas represented 68% of the cases, including those of precursor (36%) and mature (64%) cell origin. Mature cell lymphomas comprised 81% of the B-cell phenotype and 19% of the T-cell phenotype. Hodgkin lymphomas represented 32% of all cases, including 87% of the classical type and 13% of nodular lymphocyte predominant type. The geographic distribution showed 38.4% of the cases in the Southeast region, 28.7% in the Northeast, 16.1% in the South, 8.8% in the North, and 8% in the Central-west region. The distribution by age groups was 15-18 years old, 33%; 11-14 years old, 26%; 6-10 years old, 24%; and 6 years old or younger, 17%. Among mature B-cell lymphomas, most of the cases were Burkitt lymphomas (65%), followed by diffuse large B-cell lymphomas (24%). In the mature T-cell group, anaplastic large cell lymphoma, ALK-positive was the most prevalent (57%), followed by peripheral T-cell lymphoma, then not otherwise specified (25%). In the group of classic Hodgkin lymphomas, the main histological subtype was nodular sclerosis (76%). Nodular lymphocyte predominance occurred more frequently than in other series.

CONCLUSION

Some of the results found in this study may reflect the heterogeneous socioeconomical status and environmental factors of the Brazilian population in different regions.

An unusual self-limited clonal Mott cell proliferation with lymphoplasmacytic lymphoma-like features in a child with the Wiskott-Aldrich syndrome and Von Recklinghausen's neurofibromatosis

Patients with the Wiskott-Aldrich syndrome are at high risk for development of lymphomas, which are predominantly extranodal and of the immunoblastic type. We present a case of a self-limited lymphoproliferation with features of lymphoplasmacytic lymphoma arising in a patient with the Wiskott-Aldrich syndrome. The patient also had stigmata of von Recklinghausen's neurofibromatosis. The tumor was composed of CD138+, IgGkappa+, CD20-, PAX-5- Mott cells and CD5-, CD10-, CD19+, CD20+, CD43- small lymphoid B-cells that partially expressed CD23. The lymphadenopathy spontaneously resolved after a period of less than a year, and the patient had remained free of detectable lymphoproliferation for almost 4 years. He then developed Burkitt's lymphoma of the left parapharyngeal space. It is remarkable that both known lymphoproliferations with features of lymphoplasmatic lymphoma arising in patients with the Wiskott-Aldrich syndrome, this one and the previously described one, have spontaneously resolved. This observation is truly intriguing and requires further clinico-pathologic studies.

Lymphoma of mucosa-associated lymphoid tissue in common variable immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency characterized by reduced levels of all major immunoglobuline classes and recurrent c infections. The risk of non-Hodgkin's lymphoma (NHL) among patients with CVID was found to be increased in different studies. Mucosa-associated lymphoid tissue (MALT) lymphomas are a recently recognized sub-set of low-grade B-cell NHL composed of marginal zone-related cells. MALT lymphomas appear in the lymphoid tissues as a result of chronic inflammatory or autoimmune stimulation. This study briefly reviews previously published cases and reports a patient suffering from CVID with a history of chronic diarrhea and recurrent sinopulmonary infections. Despite treatment with intravenous immunoglobulin, chronic cough and wheezing progressed. Open lung biopsy showed a MALT lymphoma. Although a rare complication, pulmonary low grade B-cell lymphoma is a diagnosis that must be kept in mind in CVID patients with chronic pulmonary symptoms unresponsive to conventional therapies.

Unexpected finding of laparoscopic appendectomy: appendix MALT lymphoma in children

Mucosa-associated lymphoid tissue (MALT) lymphomas comprise a group of indolent B-cell non-Hodgkin lymphomas (NHL), which are rare in pediatric age. The clinical presentation of MALT lymphomas varies according to the location of the lymphoma. We report on a case of MALT lymphoma involving the appendix in a 6-year-old girl. A 6-year-old girl was referred to our institution in May 2005 with a diagnosis of appendicitis. The abdominal ultrasound showed slight effusion in the pelvic fossa. The patient underwent laparoscopic appendectomy using the three-trocar technique. The appendix appeared moderately hyperaemic with slight enlargement of the two-thirds of the distal portion. The postoperative course was uneventful and the girl was discharged on day 1 without any complication. The morphological and immunohistochemical examination showed typical findings of low-grade MALT lymphoma (positivity for CD20, no immunostaing for CD5 and CD10, positivity for anti-lambda light chain and low positivity for Ki-67). Further extensive examinations (abdominal MRI, gastroscopy, colonscopy and capsule endoscopy of the ileum) revealed that the lymphoma was limited to the distal two-third of the appendix (stage IA) and was not associated with any specific infection. At a recent follow-up the patients appeared to be doing well. Appendiceal MALToma is a rather uncommon pathology and, to our knowledge, there is only one report of appendiceal intussusception associated with appendiceal maltoma. According to our experience, low-grade MALToma can be managed by simple appendectomy. The histological examination should be the rule whenever an appendectomy is performed in children.

The critical role of histology in an era of genomics and proteomics: a commentary and reflection

The role of histologic examination in lymphoma diagnosis has been called into question by proponents of new technologies, such as genomics and proteomics. We review the history and salient features of morphologic evaluation in lymphoid diseases, and discuss the general and specific limitations of mature ancillary techniques, such as immunohistochemistry, flow cytometry, and molecular studies. We then speculate on the future relationship between morphology and the new genomic and proteomic technologies as they become integrated into clinical practice.

Oral mucosal MALT lymphoma clinically simulating oral facial granulomatosis

Mucosal associated lymphoid tissue (MALT) lymphoma may have specific clinical associations and molecular aberrations depending on its site of origin. We present a case of oral mucosal MALT lymphoma with clinical features simulating oral-facial granulomatosis. Dermatologists are frequently called upon for the diagnosis and treatment of mucosal lesions. Increased awareness and familiarity with oral mucosal MALT lymphoma and its clinical associations are of significant importance for optimal management of this condition.

Primary cutaneous marginal zone B-cell lymphoma of MALT type in a child

Marginal zone B-cell lymphoma (MZBCL) of mucosa-associated lymphoid tissue type is a peculiar variant of B-cell neoplasm showing distinct clinical and pathologic features. Its occurrence in children or adolescents is extremely uncommon. We describe the case of an 11-year-old boy who developed such a lymphomatous process involving primarily the skin. The tumor was characterized by a maturing plasma cell population that included immunoblasts, heavy-chain but not light-chain restriction suggestive of monoclonality, and a prevalent, focally granulomatous component of histiocytes. As an additional interesting feature, a trisomy 3 was demonstrated by fluorescence in situ hybridization analysis. The clinical, morphological, phenotypic, and genetic characteristics seen in our patient do not differ significantly from those described in primary cutaneous MZBCL occurring in adults.

MALT lymphoma in children: a report from the NHL-BFM Study Group

Marginal zone lymphomas of MALT type comprise a considerable group of indolent B-cell non-Hodgkin lymphoma (NHL) in adult patients. In childhood, however, these tumors are extremely rare, as nearly all pediatric patients have aggressive NHL. Among 2,703 children and adolescents registered into the prospective multicenter NHL-BFM treatment studies since 1986, only 4 patients (0.1%) displayed features of MALT lymphoma. These tumors were localized in the stomach, breast, lower lid, and conjunctiva, respectively and they were associated with H. pylori infection in two patients. All children are alive but long-term follow-up will be mandatory to assess the behavior of MALT lymphoma in this age group.

Remission of primary low-grade gastric lymphomas of the mucosa-associated lymphoid tissue type in immunocompromised pediatric patients

We report the remission of primary gastric lymphoma of the mucosa-associated lymphoid tissue (MALT) type in two immunocompromised pediatric patients. Patient 1, a 14-year-old boy in an immunocompromised state of unknown cause, complained of repeated abdominal pain. Examinations revealed gastric MALT with local invasion and lymph node involvement. Serum anti-Helicobacter pylori (H pylori) antibody was positive. H pylori eradication was abandoned due to its adverse effects. The MALT lesion spontaneously regressed over the next 24 months without any treatment for lymphoma. Patient 2, a 6-year-old boy, underwent cord blood transplantation for the treatment of adrenoleukodystrophy. He was administered immunosuppressants for graft-versus-host disease after transplantation. Nausea and hematochezia appeared and further examinations revealed gastric MALT with H pylori gastritis. Treatment consisting of medication for the H pylori infection alone eradicated the H pylori and completely resolved the patient’s MALT lesion, as well. Patients 1 and 2 were followed up over periods of 10 years and 3 years, respectively, without any signs of relapse. In conclusion, gastric lymphoma of the MALT type can be cured by conservative treatment even in immunocompromised pediatric patients.