Extranodal Rosai-Dorfman disease involving appendix and mesenteric nodes with a protracted course: report of a rare case lacking relationship to IgG4-related disease and review of the literature

Rosai-Dorfman disease (RDD), also known as sinus histiocytosis with massive lymphadenopathy, is a rare disease of unknown etiology that typically presents as nodal disease in young children. However, it also can present in various extranodal sites and can be difficult to recognize if not considered in the differential diagnosis. Here, we report a case of appendix involvement by extranodal RDD, which occurred in a 69-year-old woman with a long duration of 12 years for intermittent right lower quadrant pain. The patient underwent a right hemicolectomy for a clinical diagnosis of appendiceal cancer. A mixed inflammatory infiltration of mature lymphocytes, plasma cells and histiocytes exhibiting emperipolesis were indentified. Other areas had storiform fibrosis and sclerosis admixed with numerous plasma cells. These histologic features combination with immunoreactivity for CD68 and S100 protein were indicative of a diagnosis of extranodal RDD. We discuss the clinical, pathologic findings as well as differential diagnoses and consideration of a possible relationship of this entity to IgG4-related lesion.     

Maxillary and Mandibular Non-Hodgkin Lymphoma with Concurrent Periapical Endodontic Disease: Diagnosis and Management

Extranodal non-Hodgkin lymphoma (NHL) in the oral region can present similarly to diseases of odontogenic origin. The objective of this report was to describe a rare case of maxillary and mandibular NHL that presented similarly to and concurrently with lesions of odontogenic origin.A unique case of extranodal NHL, which presented at the apices of maxillary and mandibular teeth in conjunction with lesions of odontogenic origin in a 68-year-old white man, is described. The patient sought care because of a lesion in the right maxillary paranasal region that caused him paresthesia. Radiographically, periapical radiolucencies were present along teeth #5-8, #23 and 24, and #30 and 31. Biopsies of the right maxillary and anterior mandibular lesions were completed and led to a diagnosis of NHL at the apices of teeth #5-8 extending to the hard palate and granulation tissue at the apices of teeth #23 and 24. Two years later, the patient returned because of pressure and sensitivity associated with teeth #30 and 31. Vestibular swelling was noted clinically, and a multilocular periapical radiolucency was present radiographically. Via endodontic therapy and a positron emission tomographic scan, the lesion associated with teeth #30 and 31 was determined to be of both odontogenic and nonodontogenic origin because it possessed both a sinus tract associated with tooth #30 and NHL. Lesions of odontogenic and nonodontogenic origin possess diagnostic and treatment challenges because they may present similarly and/or concurrently. Thoughtful and conservative management of odontogenic lesions with associated NHL is imperative. Interprofessional collaboration and communication among providers must be thorough and clear to properly coordinate care and prevent delays in diagnosis and treatment when these entities occur together.     

The addition of rituximab to anthracycline-based chemotherapy significantly improves outcome in 'Western' patients with intravascular large B-cell lymphoma

Some case reports and a Japanese series suggest benefit from the use of rituximab in patients with intravascular large B-cell lymphoma (IVL). Rituximab efficacy was evaluated in Western patients with IVL, comparing outcome of 10 patients treated with rituximab + chemotherapy (R-CT) and of 20 patients treated with chemotherapy alone (CT). There were no significant differences in patients' characteristics between the two subgroups. The addition of rituximab was associated with improved complete remission rate (90% vs. 50%; P = 0.04), event-free survival (3-year: 89% vs. 35%; P = 0.003) and overall survival (3-year: 89% vs. 38%; P = 0.01). In conclusion, rituximab may substantially change the dismal prognosis of IVL.     

Negative images of crystalline immunoglobulin in crystal storing histiocytosis: A potential cytologic mimic of mycobacteria in smears

Two cases are described of crystal storing histiocytosis (CSH) associated with extranodal marginal zone lymphoma, presenting as lung and subcutaneous masses respectively. Fine-needle aspiration of subcutis and smears prepared from the resected lung masses showed negative images. Cytology slides of both cases were reviewed to identify cytomorphological features for the differential diagnosis between immunoglobulin crystals and mycobacteria. The crystals in CSH consist of straight and needle shaped rods with pointed or angular edges and are more variable in thickness than the uniformly thin mycobacteria. Mycobacteria show a haphazard distribution, whereas crystals are frequently present in parallel arrays. Small lymphoid or plasma cells are identified in the background of CSH, whereas a necrotic and inflammatory background is seen in mycobacteriosis. Additional samples for culture in the case of mycobacteriosis, or flow cytometry and molecular clonality testing in the case of CSH can provide critical data for a definitive diagnosis.     

Gastric and intestinal diffuse large B-cell lymphomas are clinically and immunophenotypically different. An immunohistochemical and clinical study

AIMS: To determine the immunophenotype of gastric and intestinal diffuse large B-cell lymphomas and investigate the clinical significance of patterns of antigen expression. METHODS AND RESULTS: Immunohistochemistry was performed for detection of CD10, Bcl-6, Bcl-2, MUM1 and p53 in paraffin-embedded tissue from 29 patients with primary diffuse large B-cell lymphoma of the stomach and intestine. Statistical analysis was performed using chi(2) and Fisher's exact tests. Survival data were analysed by the Kaplan-Meier method and compared using a log rank test. Thirteen of the 29 cases were of germinal centre phenotype (CD10+ or CD10-, Bcl-6+ and MUM1-). Sixteen were of activated B-cell phenotype (all CD10- and either Bcl-6-, or Bcl-6+ and MUM1+). Sixteen cases showed Bcl-2 expression. There was a statistically significant difference (P < 0.05) in immunophenotype of the neoplastic cells relating to tumour site. Of 15 gastric lymphomas, 11 were of activated B-cell phenotype and 9/14 intestinal tumours were of germinal centre phenotype. No significant survival difference was found between groups with regard to expression of any of the antigens investigated. CONCLUSIONS: Primary gastric and intestinal large cell lymphomas appear to show different patterns of antigen expression. This suggests that these tumours arise by different mechanisms and/or from different causes. Gastric diffuse large B-cell lymphomas are usually of activated B-cell phenotype that may reflect a relationship with low-grade gastric lymphomas of marginal zone type. Intestinal diffuse large B-cell lymphomas usually show a germinal centre phenotype, suggesting an origin from germinal centre B cells. In this study the tumour immunophenotype was not associated with any difference in survival.     

Extranodal diffuse large B cell lymphoma of cutaneous follicle centre lymphoma type: a study of 24 patients with non-cutaneous primary limited stage extranodal diffuse large B cell lymphoma in support of a new concept

Aigner F, Korol D, Schmitt A M & Kurrer M O
(2012) Histopathology  60, 774–784 Extranodal diffuse large B cell lymphoma of cutaneous follicle centre lymphoma type: a study of 24 patients with non‐cutaneous primary limited stage extranodal diffuse large B cell lymphoma in support of a new concept Aims: Follicle centre cell lymphoma of small cell type showing either a follicular or diffuse growth pattern similar to cutaneous follicle centre lymphoma (cFCL) has been recognized in extranodal non‐cutaneous sites. Our aim was (i) to investigate whether diffuse large B cell lymphoma (DLBCL) of cFCL type could be identified in extranodal non‐cutaneous sites and (ii) whether clinical characteristics similar to primary cFCL could be recognized. Methods and results: Of 24 extranodal non‐cutaneous DLBCLs, nine (38%) had large centrocytoid morphology and 15 (62%) were either ‘centrocytoid and centroblastic’ or ‘centroblastic and immunoblastic’. Six centrocytoid cases were Irf‐4 negative, Bcl‐6 positive and at most weakly CD10‐ or Bcl‐2‐positive by immunohistochemistry, consistent with DLBCL of cFCL type. All patients with cFCL type were stage IE and were significantly younger than other patients. Recurrences occurred in two patients and were exclusively extranodal. Conclusion: Our results suggest that DLBCL of cFCL type can be identified in extranodal non‐cutaneous sites and shows clinical characteristics similar to genuine cFCL. We propose to expand the concept of cFCL to encompass large cell lymphomas in extranodal sites.     

Advances in the management and monitoring of extranodal NK/T-cell lymphoma, nasal type

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, has a unique geographic distribution. Its pathology is characterized by marked angio-invasion and tissue necrosis. A typical NK-cell phenotype is usually present: CD2⁺, CD3 epsilon+, CD56⁺, cytotoxic molecules+ and Epstein–Barr virus (EBV)+. Magnetic Resonance Imaging helps to clearly define the local involvement. Positron Emission Tomography helps to demonstrate system spread. Various prognostic variables (International Prognostic Index or the Korean Prognostic Index) should be documented. This may include quantification of plasma EBV DNA. For localized nasal disease, radiotherapy is important, although chemotherapy is often added. Sustainable remission is observed in over half of these patients. For extra-nasal or disseminated disease, systemic chemotherapy becomes the mainstay and the prognosis is usually poor. Doxorubicin-containing regimens are not entirely satisfactory and l -asparaginase containing regimens are being investigated. Patients with poor prognostic features may be considered for an early autologous haematopoietic stem cell transplant. Allogenetic transplantation is efficacious but is associated with high transplant-related mortality.     

结外鼻型NK/T细胞淋巴瘤生物学特征和分子生物学研究热点

 结外鼻型NK／T细胞淋巴瘤（NKTL）是WHO恶性淋巴瘤分类中一种独立的病理类型,由于该病少见,对肿瘤生物学行为的研究相对较少。近几年,建立了系列细胞系和裸鼠模型,为NKTL的分子生物学研究提供了前提,奠定了基础。同时,开展了NKTL肿瘤增殖、肿瘤微环境和基因谱等方面的研究。对近几年NKTL的分子生物学研究热点进行综述,以探索进一步研究方向。