Methotrexate-associated lymphoproliferative disorder with multiple pulmonary nodules and bilateral cervical lymphadenopathy.

As has been well recognized, methotrexate (MTX) leads to a state of immunosuppression and can provide a basis for the development of lymphoproliferative disorders (LPDs). MTX-associated LPDs can affect nodal sites as well as extranodal sites, though the manifestation of an LPD in the form of multiple pulmonary nodules is rare. Here, we report two cases of MTX-associated LPD with multiple bilateral pulmonary nodules, which was a finding suggestive of lung cancer, and bilateral cervical lymphadenopathy. After withdrawal of MTX, the multiple bilateral pulmonary nodules and bilateral cervical lymphadenopathy disappeared without chemotherapy in both cases. From these results, patients with pulmonary nodules and cervical lymphadenopathy should be examined for head and neck malignant tumors. Also, physicians should carefully check the administration of MTX. In patients with an MTX-associated LPD, we need to make an early diagnosis and consider discontinuing the administration of MTX as soon as possible.

Overexpression of folate receptor alpha is an independent prognostic factor for outcomes of pancreatic cancer patients.

Pancreatic cancer has a poor prognosis; hence, novel prognostic markers and effective therapeutic targets should be identified. We aimed to evaluate folate receptor alpha (FR-α) expression in pancreatic cancer and examine its association with clinicopathological features. We utilized tissue samples from 100 primary pancreatic cancer patients who underwent surgery. FR-α was expressed in 37 of 100 cases (37%). The FR-α-positive group (median, 18.8 months) had a significantly poorer prognosis than the FR-α-negative group [median 21.3 months; HR 1.89 (1.12-3.12); P = 0.017]. These groups were not significantly different regarding progression-free survival (P = 0.196). Furthermore, other serum tumor markers including CA19-9 (mean, 186 vs. 822 U/ml; P = 0.001), Dupan-2 (286 vs. 1133 U/ml; P = 0.000), and Span-1 (69.7 vs. 171.9 U/ml; P = 0.006) were significantly downregulated in the FR-α-positive group. CA19-9 was another prognostic factor, in addition to FR-α, and patient prognosis showed clear stratification curves with the expression of these two molecules. Along with CA19-9, FR-α expression was an independent prognostic factor for the overall survival. FR-α and CA19-9 helped predict patient prognosis based on stratification curves.

Characteristic Distribution Pattern of CD30-positive Cytotoxic T Cells Aids Diagnosis of Kikuchi-Fujimoto Disease.

INTRODUCTION: Histiocytic necrotizing lymphadenitis (or Kikuchi-Fujimoto disease) frequently occurs in Asian young adult females and typically presents as cervical lymphadenopathy with unknown etiology. Although large immunoblasts frequently appear in Kikuchi-Fujimoto disease, the diffuse infiltration of these cells can cause difficulty in establishing a differential diagnosis from lymphoma. In such cases, CD30 immunostaining may be used; however, the extent or distribution pattern of CD30-positive cells in Kikuchi-Fujimoto disease remains largely unknown. Here we investigated the expression of CD30 and its clinicopathologic significance. MATERIALS AND METHODS: We investigated 30 Kikuchi-Fujimoto disease and 16 control [6, systemic lupus erythematosus (SLE); 10, reactive lymphoid hyperplasia (RLH)] cases. RESULTS: The number of CD30-positive cells in Kikuchi-Fujimoto disease was significantly more than that in SLE and RLH, and majority of these cells were located around necrotic areas. Moreover, double immunohistochemical staining showed these CD30-positive cells to be CD8-positive cytotoxic T cells, suggesting that activated cytotoxic T cells around necrotic areas are a characteristic feature of this disease. Clinicopathologic analysis showed that cases with abundant CD30-positive cells were predominantly female with only mild symptoms and normal laboratory data. CONCLUSIONS: In Kikuchi-Fujimoto disease cases, CD30-positive cytotoxic T cells were abundant around necrotic areas; this histologic feature may be helpful to differentiate this disease from SLE and RLH.

Frequent downregulation of BTB and CNC homology 2 expression in Epstein-Barr virus-positive diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is the most common B-cell lymphoma subtype, and the Epstein-Barr virus (EBV)-positive subtype of DLBCL is known to show a more aggressive clinical behavior than the EBV-negative one. BTB and CNC homology 2 (BACH2) has been highlighted as a tumor suppressor in hematopoietic malignancies; however, the role of BACH2 in EBV-positive DLBCL is unclear. In the present study, BACH2 expression and its significance were studied in 23 EBV-positive and 43 EBV-negative patient samples. Immunohistochemistry revealed BACH2 downregulation in EBV-positive cases (P < 0.0001), although biallelic deletion of BACH2 was not detected by FISH. Next, we analyzed the contribution of BACH2 negativity to aggressiveness in EBV-positive B-cell lymphomas using FL-18 (EBV-negative) and FL-18-EB cells (FL-18 sister cell line, EBV-positive). In BACH2-transfected FL-18-EB cells, downregulation of phosphorylated transforming growth factor-ß-activated kinase 1 (pTAK1) and suppression in p65 nuclear fractions were observed by Western blot analysis contrary to non-transfected FL-18-EB cells. In patient samples, pTAK1 expression and significant nuclear p65, p50, and p52 localization were detected immunohistochemically in BACH2-negative DLBCL (P < 0.0001, P = 0.006, and P = 0.001, respectively), suggesting that BACH2 downregulation contributes to constitutive activation of the nuclear factor-κB pathway through TAK1 phosphorylation in BACH2-negative DLBCL (most EBV-positive cases). Although further molecular and pathological studies are warranted to clarify the detailed mechanisms, downregulation of BACH2 may contribute to constitutive activation of the nuclear factor-κB pathway through TAK1 activation.

Clinicopathological analysis of primary central nervous system NK/T cell lymphoma: rare and localized aggressive tumour among extranasal NK/T cell tumours.

AIMS: The central nervous system (CNS) is a rare primary site of non-Hodgkin lymphoma. Although direct invasion of nasal natural killer (NK)/T cell tumours into CNS is reported occasionally, primary CNS NK/T cell lymphoma is extremely rare, and the clinicopathological features of primary CNS NK/T cell lymphoma remain largely unknown. METHODS AND RESULTS: We identified four cases from our consultation files and analysed the clinicopathological features. Three were immunocompetent and one was immunosuppressed. There were three males and one female and their ages ranged from 21 to 77 years (median: 46 years). Radiotherapy was rendered for all patients, and methotrexate was administered to two patients. The overall survival was 4-29 months (median, 19 months) for the three immunocompetent patients. Neoplastic cells exhibited medium to large atypical nuclei. Angiocentric growth and necrosis were observed. The immunophenotype was typical of NK cell tumours: CD3ε, 100%; CD56, 67%; CD5, 50%; cytotoxic molecules, 100%; Epstein-Barr virus encoded small RNA (EBER), 100% and T cell receptor (TCR)-ß or γ, 0%. No TCR-gene rearrangements were detected. Reviewing 10 additional cases from the literature and comparing with extranasal NK/T cell lymphoma of the more frequent origins (skin or gastrointestinal tract), primary CNS NK/T cell lymphoma was diagnosed at an earlier stage without B symptoms but exhibited aggressive clinical behaviours. CONCLUSIONS: Although extremely rare, primary CNS NK/T cell lymphoma does occur and should always be included in the differential diagnosis and we should apply relevant markers routinely in conjunction with exploring the patient background. The accumulation of cases is indispensable to establish an effective treatment strategy for this rare and aggressive malignancy.

Protocadherin γ A3 is expressed in follicular lymphoma irrespective of BCL2 status and is associated with tumor cell growth.

Protocadherin genes (PCDHs) have been suggested to act as tumor suppressor genes in various tumor types. Previous studies have demonstrated the upregulation of certain PCDH­Î³ subfamily genes in nodal and duodenal follicular lymphoma (FL) using gene expression analyses. However, the mechanisms and associated molecular function of PCDH­Î³ subfamily gene upregulation in FL remain to be elucidated. The present study examined the expression of PCDHGA3, an upregulated PCDH­Î³ gene subfamily member, in B­cell lymphoma 2 (BCL2)­positive and ­negative FL, and evaluated its association with tumor cell proliferation in an FL­derived cell line. Immunohistochemical analysis demonstrated that the majority of FL grade 1­2 samples (19/20; 95%) and over half of grade 3A FL samples (5/9; 56%) were PCDHGA3­positive, whereas only 1/17 reactive lymphoid hyperplasia samples was positive. Notably, this positivity was widely observed in samples of BCL2­negative FL (13/15; 87%) and FL with diffuse area (10/10; 100%). The FL­derived cell line FL18 exhibited strong PCDHGA3 expression, similar to the patient samples, and its proliferation was suppressed by PCDHGA3 gene knockdown. Genes expressed concomitantly with PCDHGA3 were selected from gene expression data, and TNFRSF6B, a member of the tumor necrosis factor receptor superfamily, was among the top five most strongly correlated genes. Coexpression of TNFRSF6B and PCDHGA3 was observed immunohistochemically in FL18 cells, suggesting potential cooperation in tumor cell maintenance. In conclusion, the results of the present study indicated that PCDHGA3 was expressed in FL irrespective of BCL2 status and grading and was associated with cell proliferation. Further studies involving molecular genetic analyses are required to elucidate the mechanisms underlying the activity of PCDHGA3 in FL.

CD10 down expression in follicular lymphoma correlates with gastrointestinal lesion involving the stomach and large intestine.

Follicular lymphoma (FL) shows co-expression of B-cell lymphoma 2 (BCL2) and CD10, whereas downexpression of CD10 is occasionally experienced in gastrointestinal (GI) FL with unknown significance. Gastrointestinal FL is a rare variant of FL, and its similarity with mucosa-associated lymphoid tissue lymphoma was reported. We investigated the clinicopathological and genetic features of CD10 downexpressed (CD10down ) GI-FL. The diagnosis of CD10down FL was carried out with a combination of pathological and molecular analyses. The incidence of CD10down GI-FL was shown in 35/172 (20.3%) cases, which was more frequent than nodal FL (3.5%, P < 0.001). The difference was additionally significant between GI-FL and nodal FL when the analysis was confined to primary GI-FL (55.2% vs 3.5%, P < 0.001). Compared to CD10+ GI-FL, CD10down GI-FL significantly involved the stomach or large intestine (P = 0.015), and additionally showed the downexpression of BCL6 (P < 0.001). The follicular dendritic cell meshwork often showed a duodenal pattern in the CD10down group (P = 0.12). Furthermore, a lymphoepithelial lesion was observed in 5/12 (40%) gastric FL cases, which indicated caution in the differentiation of mucosa-associated lymphoid tissue lymphoma. Molecular analyses were undertaken in seven cases of CD10down GI-FL, and an identical clone was found between CD10down follicles and CD10+ BCL2+ neoplastic follicles. In the diagnosis of cases with CD10down BCL2+ follicles, careful examination with molecular studies should be carried out.

Clinicopathological features of 49 primary gastrointestinal diffuse large B-cell lymphoma cases; comparison with location, cell-of-origin, and frequency of MYD88 L265P.

The gastrointestinal (GI) tract is the most common primary site of extranodal diffuse large B-cell lymphoma (DLBCL), with approximately one-third of extranodal DLBCL occurring in the GI tract. We investigated the clinicopathological features and immunohistochemically-assessed cell-of-origin of 49 GI DLBCL cases (stomach, 24; small intestine, 10; colon, 15) and also examined the presence of MYD88 L265P as recently this mutation has been frequently identified in ABC-like DLBCL, particularly in extranodal sites. Small intestinal DLBCL was characterized by the preponderance of women (P = 0.041) and elevated LDH (P = 0.002) and soluble interleukin-2 receptor (P = 0.033). Small intestinal DLBCL more frequently showed anemia (P = 0.031) and elevated CRP (P = 0.029) than gastric DLBCL. ABC-like phenotype was seen in 71.4 % cases (stomach, 79 %; small intestine, 70 %; colon, 60 %). MYD88 L265P was detected in 6.1 % cases; all were primary gastric DLBCL with ABC-like phenotype but had no distinct clinicopathological features. In conclusion, GI DLBCL had different clinicopathological features according to the primary site especially in the small intestine. Also, MYD88 L265P had little involvement in GI DLBCL compared with other extranodal DLBCLs, suggesting that its pathogenesis might be different from that of organs with a high frequency of MYD88 L265P.

Frequent MYD88 L265P and CD79B Mutations in Primary Breast Diffuse Large B-Cell Lymphoma.

Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare disease comprising <3% of extranodal lymphomas. It frequently reveals an activated B-cell (ABC)-like phenotype. ABC-like DLBCL was reported to have gain-of-function mutations in MYD88, CD79B, CARD11, and TNFAIP3, resulting in constitutive activation of the NFκB pathway. Because of the rare occurrence of PB-DLBCL, the frequency of MYD88 and CD79B mutations is still unknown. We used Sanger sequencing to study these mutations from 46 breast DLBCL cases and also investigated the associated clinicopathologic factors. MYD88 L265P was confirmed by allele-specific polymerase chain reaction and compared with the Sanger sequencing results. MYD88 L265P and CD79B mutations were detected in 27/46 (58.7%) and 11/33 (33.3%) cases, respectively. Twenty-eight of 46 cases met the criteria for PB-DLBCL, and the latter 18 cases were further classified as clinical breast DLBCL (CLB-DLBCL). The frequency of MYD88 L265P and CD79B mutations was 16/28 (57.1%) and 9/23 (39.1%), respectively, in PB-DLBCL and 11/18 (61.1%) and 2/10 (20%), respectively, in CLB-DLBCL. When the cutoff value was set at ΔCt≤1, the result of allele-specific polymerase chain reaction for MYD88 corresponded to those of the Sanger sequence at 92.6% sensitivity and 100% specificity. According to Choi's algorithm, 16/27 (59.3%) demonstrated an ABC-like phenotype in PB-DLBCL, and 15/18 (83.3%) demonstrated an ABC-like phenotype in CLB-DLBCL. In conclusion, MYD88 L265P and CD79B mutations were frequently detected in PB-DLBCL, and they may be key molecules associated with PB-DLBCL lymphomagenesis. Further analysis will be required to clarify the mechanism of its pathogenesis.

Elevation of serum interleukins 8, 4, and 1ß levels in patients with gastrointestinal low-grade B-cell lymphoma.

Proinflammatory cytokines that are produced by helper T cells (Th) regulate immune reactions, facilitate class switching of B cells, and prolong the lifespan of B and T cells. Eradication therapy using antibiotics is sometimes effective against gastrointestinal (GI) malignant lymphoma, suggesting that the tumor development or progression is affected by the inflammatory microenvironment. In the present study, serum samples from 148 patients with various subtypes of malignant lymphoma were tested for 11 proinflammatory Th1/Th2 cytokines. In the comparison by subtype or GI lesions, serum interleukin (IL)-8 (P = 6.7E-05), IL-4 (P = 7.5E-05), and IL-1ß (P = 0.0043) levels showed significant differences among subtypes, being particularly elevated in follicular lymphomas (FL) and mucosa-associated lymphoid tissue (MALT) lymphomas. Serum IL-8 levels were elevated in GI-FL and MALT lymphomas, and serum IL-4 and IL-1 ß levels were elevated in MALT lymphomas. These findings show that GI low-grade B-cell lymphoma could develop against the background of an inflammatory microenvironment. Thus, these cytokines may be useful as diagnostic markers and could provide new insights into tumor development.

Clinicopathologic analysis of 6 lymphomatoid gastropathy cases: expanding the disease spectrum to CD4-CD8+ cases.

Lymphomatoid gastropathy, which was first reported in 2010, is a rare NK-cell proliferation of cyCD3, CD4, CD5, CD8, CD56 phenotypes with unknown etiology. The diagnosis is challenging, as there is histopathologic similarity to malignant lymphoma. In the 2010 report on 10 cases, all lesions were located in the stomach, and all regressed without any therapy. In the present study, we analyzed 6 cases of lymphomatoid gastropathy by investigating the clinicopathologic, immunohistochemical, and molecular findings. Endoscopic and morphologic appearances of all cases were consistent with previous reports, but 2 cases showed previously unreported unique immunophenotypes of CD4CD8. Three of 6 patients underwent lower gastrointestinal examination (1 case underwent double-balloon endoscopic examination), but no patient had lesions in the lower gastrointestinal tract. No obvious difference of histology was found between the cases of CD4-CD8-typical phenotype and ones of CD4CD8 phenotype. Both cases had similar clinical behavior as the other 4 cases, implying that the spectrum of the disease is broader than initially thought. Careful clinical and endoscopic follow-up is required for the diagnosis of lymphomatoid gastropathy, and additional case studies and molecular studies are warranted to further investigate the pathophysiology of this peculiar benign mimic of lymphoma.