Long-term progression-free survival of mantle cell lymphoma after intensive front-line immunochemotherapy with in vivo-purged stem cell rescue: a nonrandomized phase 2 multicenter study by the Nordic Lymphoma Group.

Mantle cell lymphoma (MCL) is considered incurable. Intensive immunochemotherapy with stem cell support has not been tested in large, prospective series. In the 2nd Nordic MCL trial, we treated 160 consecutive, untreated patients younger than 66 years in a phase 2 protocol with dose-intensified induction immunochemotherapy with rituximab (R) + cyclophosphamide, vincristine, doxorubicin, prednisone (maxi-CHOP), alternating with R + high-dose cytarabine. Responders received high-dose chemotherapy with BEAM or BEAC (carmustine, etoposide, cytarabine, and melphalan/cyclophosphamide) with R-in vivo purged autologous stem cell support. Overall and complete response was achieved in 96% and 54%, respectively. The 6-year overall, event-free, and progression-free survival were 70%, 56%, and 66%, respectively, with no relapses occurring after 5 years. Multivariate analysis showed Ki-67 to be the sole independent predictor of event-free survival. The nonrelapse mortality was 5%. The majority of stem cell products and patients assessed with polymerase chain reaction (PCR) after transplantation were negative. Compared with our historical control, the Nordic MCL-1 trial, the event-free, overall, and progression-free survival, the duration of molecular remission, and the proportion of PCR-negative stem cell products were significantly increased (P < .001). Intensive immunochemotherapy with in vivo purged stem cell support can lead to long-term progression-free survival of MCL and perhaps cure. Registered at www.isrctn.org as #ISRCTN 87866680.

Indistinguishable genomic profiles and shared prognostic markers in undifferentiated pleomorphic sarcoma and leiomyosarcoma: different sides of a single coin?

Soft tissue sarcoma (STS) diagnostics and prognostics are challenging, particularly in highly malignant and pleomorphic subtypes such as undifferentiated pleomorphic sarcoma (UPS) and leiomyosarcoma (LMS). We applied 32K BAC arrays and gene expression profiling to 18 extremity soft tissue LMS and 31 extremity soft tissue UPS with the aim of identifying molecular subtype signatures and genomic prognostic markers. Both the gains/losses and gene expression signatures revealed striking similarities between UPS and LMS, which were indistinguishable using unsupervised hierarchical cluster analysis and significance analysis for microarrays. Gene expression analysis revealed just nine genes, among them tropomyosin beta, which were differentially expressed. Loss of 4q31 (encompassing the SMAD1 locus), loss of 18q22, and tumor necrosis were identified as independent predictors of metastasis in multivariate stepwise Cox regression analysis. Combined analysis applying loss of 4q31 and 18q22 and the presence of necrosis improved the area under receiver operating characteristic curve for metastasis prediction from 0.64 to 0.86. The extensive genetic similarities between extremity soft tissue UPS and LMS suggest a shared lineage of these STS subtypes and the new and independent genetic prognosticators identified hold promise for refined prognostic determination in high-grade, genetically complex STS.

High-resolution molecular cytogenetic analysis of Wilms tumors highlights diagnostic difficulties among small round cell kidney tumors.

Many solid tumors exhibit characteristic gene fusions, which are reflected by balanced translocations at the cytogenetic level. These changes might be useful diagnostic and prognostic tools. In Wilms tumor (WT, nephroblastoma) no fusions genes or recurrent balanced translocations have been described thus far. To screen for cryptic balanced translocations, we have analyzed 17 renal neoplasms, histopathologically classified as WT, by a combination of G-banding, multicolor FISH, and subtelomeric FISH. This approach revealed several submicroscopic chromosomal aberrations and three different seemingly balanced translocations, resulting in a heterozygous deletion of HACE1, an EWSR1/ERG fusion, and an EWSR1/FLI1 fusion, respectively. As EWSR1 rearrangements are known to be a characteristic of Ewing tumors (ET), our findings illustrate the diagnostic problems regarding small cell kidney tumors and strongly argue for the need of adjuvant diagnostic techniques in this group of neoplasms. In summary, our genomic screening approach proved efficient in finding structural chromosomal aberrations. The fact that no recurrent translocations were found in the WTs of this study argues against the presence of a frequent pathognomonic translocation in this disease entity.

Pesticide exposure as risk factor for non-Hodgkin lymphoma including histopathological subgroup analysis.

We report a population based case-control study of exposure to pesticides as risk factor for non-Hodgkin lymphoma (NHL). Male and female subjects aged 18-74 years living in Sweden were included during December 1, 1999, to April 30, 2002. Controls were selected from the national population registry. Exposure to different agents was assessed by questionnaire. In total 910 (91 %) cases and 1016 (92%) controls participated. Exposure to herbicides gave odds ratio (OR) 1.72, 95% confidence interval (CI) 1.18-2.51. Regarding phenoxyacetic acids highest risk was calculated for MCPA; OR 2.81, 95% CI 1.27-6.22, all these cases had a latency period >10 years. Exposure to glyphosate gave OR 2.02, 95% CI 1.10-3.71 and with >10 years latency period OR 2.26, 95% CI 1.16-4.40. Insecticides overall gave OR 1.28, 95% CI 0.96-1.72 and impregnating agents OR 1.57, 95% CI 1.07-2.30. Results are also presented for different entities of NHL. In conclusion our study confirmed an association between exposure to phenoxyacetic acids and NHL and the association with glyphosate was considerably strengthened.

Diagnostic and prognostic gene expression signatures in 177 soft tissue sarcomas: hypoxia-induced transcription profile signifies metastatic potential.

BACKGROUND: Soft tissue sarcoma (STS) diagnosis is challenging because of a multitude of histopathological subtypes, different genetic characteristics, and frequent intratumoral pleomorphism. One-third of STS metastasize and current risk-stratification is suboptimal, therefore, novel diagnostic and prognostic markers would be clinically valuable. We assessed the diagnostic and prognostic value of array-based gene expression profiles using 27 k cDNA microarrays in 177, mainly high-grade, STS of 13 histopathological subtypes. RESULTS: Unsupervised analysis resulted in two major clusters--one mainly containing STS characterized by type-specific genetic alterations and the other with a predominance of genetically complex and pleomorphic STS. Synovial sarcomas, myxoid/round-cell liposarcomas, and gastrointestinal stromal tumors clustered tightly within the former cluster and discriminatory signatures for these were characterized by developmental genes from the EGFR, FGFR, Wnt, Notch, Hedgehog, RAR and KIT signaling pathways. The more pleomorphic STS subtypes, e.g. leiomyosarcoma, malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma and dedifferentiated/pleomorphic liposarcoma, were part of the latter cluster and were characterized by relatively heterogeneous profiles, although subclusters herein were identified. A prognostic signature partly characterized by hypoxia-related genes was identified among 89 genetically complex pleomorphic primary STS and could, in a multivariate analysis including established prognostic markers, independently predict the risk of metastasis with a hazard ratio of 2.2 (P = 0.04). CONCLUSION: Diagnostic gene expression profiles linking signaling pathways to the different STS subtypes were demonstrated and a hypoxia-induced metastatic profile was identified in the pleomorphic, high-grade STS. These findings verify diagnostic utility and application of expression data for improved selection of high-risk STS patients.

CD40 expression identifies a prognostically favourable subgroup of diffuse large B-cell lymphoma.

In order to confirm our earlier findings of the prognostic effects of CD23 and CD40 expression in diffuse large B-cell lymphoma (DLBCL), possibly due to association with the germinal center (GC) phenotype and/or an increased autologous tumour response, tumour specimens from 125 patients with de novo DLBCL were investigated for immunohistochemical expression of CD23, CD40, BCL6, CD10, MUM1, CD4 and CD8. CD40 was positive in 64% and was associated with improved overall survival (p = 0.03). A GC phenotype was present in 47%, and was also associated with a better overall survival (p = 0.006) but did not correlate with CD40-expression. There was no correlation between amount of tumour infiltrating T-cells and CD40-positivity. CD23 was positive in 10% and expression did not correlate with prognosis. In conclusion, the prognostic effect of CD40 expression was confirmed, but did not correlate with GC-phenotype or T-cell infiltration.

Fine-needle aspiration of soft tissue leiomyosarcoma: an analysis of the most common cytologic findings and the value of ancillary techniques.

This study aims to determine the diagnostic accuracy of fine-needle aspiration cytology (FNAC) of primary leiomyosarcoma (LMS) of soft tissue and to review diagnostic criteria and adjunctive methods, which can contribute to a confident diagnosis. We evaluated the preoperative FNAC in 89 patients with primary LMS for the following: cytomorphology and correspondence of FNA to histological features of excised tumors and clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed. An unequivocal, malignant diagnosis was rendered by FNAC in 78 cases; 74 tumors were diagnosed as sarcoma, of which 31 as LMS or suspicion of LMS. In addition, three smears were labeled as malignant tumor, one as carcinoma metastasis, and three as neurilemmoma. Seven aspirates were inconclusive and one insufficient. On reevaluation, the diagnostic smears in most cases contained tumor cell fascicles with an admixture of dispersed cells or stripped nuclei. The most common cells were spindle cells with elongated, blunt-ended, segmented or fusiform nuclei, and round/polygonal cells, often with rounded or indented nuclei. In addition, 51 cases showed pleomorphic, often multinucleated cells. Osteoclasts, intranuclear vacuoles, and mitoses occurred in 14, 47, and 27 cases, respectively. Thus, most high-grade LMSs have cytologic features that allow diagnosis of sarcoma. Ancillary studies can confirm the diagnosis of LMS and help in the correct interpretation of predominant spindle-cell or epitheloid-cell smears resembling neurilemoma or carcinoma, respectively.

Fine-needle aspiration of neurilemoma (schwannoma). A clinicocytopathologic study of 116 patients.

The preoperative fine-needle aspiration cytology (FNAC) diagnoses in 116 surgically excised neurilemomas were reviewed and compared with the corresponding histopathologic diagnoses made on surgical specimens and with clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed. An unequivocal, benign diagnosis was rendered by FNAC in 80 cases, 67 of which were correctly labelled as neurilemoma in a review of the original cytology reports. There were 6 false-positive malignant diagnoses while 23 smears were considered insufficient and 7 inconclusive as to whether benign or malignant. On reevaluation, the diagnostic smears in most cases contained spindle cells with wavy nuclei embedded in a fibrillar, occasionally collagenous, and/or myxoid matrix and Antoni A/Antoni B tissue fragments. A moderate to abundant admixture of round to oval cells was also frequent. Nuclear palisading was seen in 41 smears with distinctive Verocay bodies in 10. Markedly pleomorphic nuclei were seen in smears from 8 ancient and 6 conventional neurilemomas, and slight to moderate nuclear pleomorphism was observed in 38 additional cases. Thus most neurilemomas have distinct cytomorphologic features that allow correct diagnosis. The major problem in FNAC of neurilemoma is to obtain sufficient material. Furthermore aspirates showing predominantly Antoni A features, nuclear pleomorphism, and/or myxoid changes can easily be confused with other types of benign or malignant soft-tissue tumors.

Improved prognostication in soft tissue sarcoma: independent information from vascular invasion, necrosis, growth pattern, and immunostaining using whole-tumor sections and tissue microarrays.

In 140 mixed primary soft tissue sarcomas with a median follow-up of 6 years, the prognostic importance of tumor size, tumor depth, grade, necrosis, vascular invasion, and peripheral growth pattern (pushing versus infiltrating) was evaluated on whole-tumor sections. Immunohistochemical expression of Ki-67, p53, cyclin A, bcl-2, beta-catenin, CD44, and P-glycoprotein was determined using tissue microarray from the peripheral growth zone. Local recurrences developed in 17% of the patients and correlated with necrosis, vascular invasion, and cyclin A expression. No local recurrence developed in tumors with a pushing growth pattern, regardless of tumor grade and depth. Metastasis developed in 39% of the patients. Vascular invasion was identified in 36% of the tumors and was the strongest prognostic factor for metastasis with a hazard ratio of 3.5. Growth pattern and tumor necrosis were also strong prognostic factors for metastasis, whereas malignancy grade, tumor size, and tumor depth did not have any independent prognostic value. Immunostaining showed independent prognostic information for Ki-67, beta-catenin, CD44, and P-glycoprotein. The results indicate that whole-tumor sections could facilitate identification of vascular invasion, necrosis, and peripheral growth pattern and that immunohistochemical profiling from the growth zone also provides independent prognostic information for metastasis in soft tissue sarcoma.

Histopathological and cell biological characteristics of ductal carcinoma in situ (DCIS) of the breast-a comparison between the primary DCIS and subsequent ipsilateral and contralateral tumours.

The rate of ipsilateral local recurrence after ductal carcinoma in situ (DCIS) varies (between 5% and 30%) and depends on the type of operation (mastectomy vs. breast-conserving operation), and whether postoperative radiotherapy has been used. Ipsilateral local recurrence can either emanate from the primary lesion or be a new primary tumour. Contralateral lesions may also develop after DCIS. We compared histopathological and cell biological characteristics in 37 subsequent ipsilateral tumours (25 DCIS and 12 invasive cancers) and 13 subsequent contralateral invasive breast cancers with their corresponding primary DCIS. The histopathological parameters were re-evaluated and the cell biological factors were analysed using conventional immunohistochemical techniques in paraffin-embedded material. The concordance rate for high grade (nuclear grade 3) vs. non-high grade (nuclear grades 1+2) between the primary DCIS and the subsequent ipsilateral tumour was higher than between the primary DCIS and the subsequent contralateral invasive cancer (68% vs. 31%). Similar patterns in the concordance rates between the primary DCIS and ipsilateral vs. contralateral tumours were also found in the oestrogen receptor status (83% vs. 50%) and the progesterone receptor status (87% vs. 58%). The pattern persisted in the other factors examined (p53, c-erbB2, bcl-2 and Ki67), although it was less pronounced. The overall high rate of concordance in the characteristics between the primary DCIS and the subsequent ipsilateral tumours suggests that, in most cases, they represent true local recurrences. Subsequent contralateral tumours are more likely to be new primary cancers.

Fine-needle aspiration of primary osteosarcoma: a cytological-histological study.

This study aims to determine the diagnostic accuracy of fine-needle aspiration (FNA) evaluation of primary osteosarcoma (OS) and to review diagnostic criteria and adjunctive methods that can contribute to a confident diagnosis of OS in cytological smears. We evaluated FNA smears of OS in 59 patients for the following: cytomorphology and occurrence of osteoid, usefulness of adjunctive methods in evaluation of FNA smears and correspondence of FNA to the clinical data, and the histological features of excised tumors. Reliable cytological criteria of malignancy were found in 49 smears of high-grade OS. These criteria, correlated with radiographic studies and complemented by ancillary techniques, allowed diagnosis of OS or suspicion of OS in 44 cases. An additional four smears were diagnosed as sarcoma and one case was diagnosed erroneously as being carcinoma metastasis. There were no false positive or false negative diagnoses. We conclude that FNA smears from high-grade OS have characteristic features, which together with clinical and radiological data and ancillary studies allow correct diagnosis in most tumors.

Expression profiling using tissue microarray in 211 malignant fibrous histiocytomas confirms the prognostic value of Ki-67.

The tissue microarray technology is a high-throughput technique that allows studies of multiple markers in large tumor materials. We performed immunohistochemical profiling using tissue microarray and immunostaining for Ki-67, p53, bcl-2, CD44, cyclin A and Pgp in a series of 211 malignant fibrous histiocytomas (MFHs) with correlation to prognosis. Tissue from 50 local recurrences and 20 metastases was available for comparison with the primary tumors. In univariate analysis, Ki-67 was the only immunohistochemical marker significantly correlated with metastasis with a hazard ratio of 1.9. Multivariate analysis, with tumor size, depth, necrosis, vascular invasion, mitotic rate and Ki-67 expression, revealed an independent prognostic value of tumor size and Ki-67. Local recurrences did not differ from the corresponding primary tumors, whereas metastases showed a trend for upregulation of cyclin A and Pgp. In this large series of MFHs, a tumor size greater than 8 cm and a Ki-67 index of more than 20% were strong and independent prognostic factors for metastasis. In contrast, p53, bcl-2, CD44, cyclin A and Pgp, which have previously been suggested as prognostic factors in soft tissue sarcomas, did not show such correlations. Hence, we suggest that proliferation, as measured by Ki-67 index, should be considered as a prognostic marker in clinical management of pleomorphic soft tissue sarcomas.

Fine-needle aspiration of synovial sarcoma: criteria for diagnosis: retrospective reexamination of 37 cases, including ancillary diagnostics. A Scandinavian Sarcoma Group study.

The cytologic criteria of synovial sarcoma in fine-needle aspirates were defined by a retrospective examination of 37 primary tumors. Irrespective of subtype, a typical pattern at low power was found, provided the yield was rich. The typical pattern was a mixture of dispersed cells with the presence of striped nuclei and cell-tight tumor tissue fragments with irregular borders. Often a branching network of vessels was present in the fragments, imitating a true vascular tumor. Except in poorly differentiated synovial sarcomas, the tumor cells were, small to medium in size, with rounded, ovoid, or fusiform bland nuclei with inconspicuous nucleoli. In the biphasic variant, small glandular- or acinar-like structures were present, although not in all cases. In the poorly differentiated type, however, the cellular pleomorphism was marked with the presence of cells with irregular nuclei and rhabdomyoblast-like cells, corresponding to the pleomorphic variant. The Ewing's sarcoma-like and the atypical spindle cell variants of poorly differentiated synovial sarcoma were not diagnosed in the material. An unequivocal diagnosis of sarcoma is possible when the yield is rich. However, ancillary diagnostics are necessary for a correct diagnosis, to avoid important pitfalls, such as other sarcomas with bland tumor cells and vessel-rich tumor fragments, in particular, solitary fibrous tumor and true hemangiopericytoma. Electron microscopic and/or molecular genetic analyses were better diagnostic adjuncts than immunocytochemistry.

Prognostic value of proliferation in pleomorphic soft tissue sarcomas: a new look at an old measure.

Though proliferation has repeatedly shown a prognostic role in sarcomas, it has not reached clinical application. We performed a comprehensive evaluation of the prognostic role of 5 proliferation measures in a large series of soft tissue sarcomas of the extremities and the trunk wall. One hundred ninety-six primary soft tissue sarcomas of the extremities and the trunk wall were subjected to DNA flow cytometry for quantification of S-phase fraction and to immunohistochemical evaluation of Ki-67, Top2a, p21, and p27Kip1. In univariate analysis, positive expression of Ki-67 (hazard ratio = 4.5, CI = 1.6-12.1), Top2a (hazard ratio = 2.2, CI = 1.2-3.5) and high S-phase fraction (hazard ratio = 1.8, CI = 1.2-3.7) significantly correlated with risk for metastasis. When combined with currently used prognostic factors, Ki-67, S-phase fraction and Top2a fraction contributed to refined identification of prognostic risk groups. Proliferation, as assessed by expression of Ki-67 and Top2a and evaluation of S-phase fraction and applied to statistical decision-tree models, provides prognostic information in soft tissue sarcomas of the extremity and trunk wall. Though proliferation contributes independently to currently applied prognosticators, its role is particularly strong when few other factors are available, which suggests a role in preoperative decision-making related to identification of high-risk individuals who would benefit from neoadjuvant therapy.

Ezrin expression predicts local recurrence and development of metastases in soft tissue sarcomas.

BACKGROUND: Ezrin is a cytoskeletal protein involved in tumour growth and invasion. Ezrin expression has been suggested to play a role in metastasis in paediatric osteosarcoma and rhabdomyosarcoma. AIM: To evaluate the prognostic role of ezrin in a large series of soft tissue sarcoma of the extremities and trunk wall. METHODS: Ezrin expression was evaluated by immunohistochemistry on tissue microarrays from a mixed series of 256 soft tissue sarcomas. The expression patterns were correlated to local recurrence and metastasis as well as to established prognostic factors in soft tissue sarcoma. RESULTS: Increased ezrin expression predicted development of metastasis (HR=1.8, 95% CI 1.1 to 2.8; p=0.007) and local recurrence, also after adjustment for surgical margin (HR=2.4, 95% CI 1.4 to 4.3; p=0.02). Correlations to established prognostic factors showed strong associations between ezrin and necrosis (OR=3.9, p<0.0001) and ezrin and growth pattern (OR=3.1, p=0.03). CONCLUSIONS: Ezrin independently predicts development of local recurrences and metastases in soft tissue sarcomas. The possibility of preoperative evaluation makes ezrin a potential marker for identification of high-risk sarcoma patients who would benefit from neoadjuvant therapy.

Sarcomas associated with hereditary nonpolyposis colorectal cancer: broad anatomical and morphological spectrum.

Hereditary nonpolyposis colorectal cancer (HNPCC) is primarily linked to colorectal and endometrial cancer, but is associated with a broad tumor spectrum. Though not formally part of the syndrome, occasional sarcomas have been reported in individuals with HNPCC. We used the national Danish HNPCC-register to identify HNPCC families in which sarcomas had been diagnosed. Fourteen sarcomas were identified in families with mutations in MSH2, MSH6, and MLH1. The median age at sarcoma diagnosis was 43 (15-74) years. Soft tissue sarcomas predominated followed by uterine sarcomas and eight histopathological subtypes were represented with recurrent diagnoses of liposarcoma, leiomyosarcoma, and carcinosarcoma. Tumor tissue from eight cases was available for analysis of mismatch-repair (MMR) status using immunohistochemical staining and analysis of microsatellite instability, which revealed MMR defects in six of the eight tumors investigated. This suggests that sarcomas may be part of the HNPCC tumor spectrum and that colorectal cancer should be considered in the family history of sarcoma patients.

Tissue microarray is inappropriate for analysis of BCL6 expression in diffuse large B-cell lymphoma.

OBJECTIVE: In this study, our aim was to investigate how different immunohistochemical techniques may influence the result of BCL6 positivity and categorization in germinal center (GC) and non-GC derived diffuse large B-cell lymphoma (DLBCL), as it has been proposed that classification of DLBCL according to cell-of-origin by immunohistochemistry may be performed as a routine procedure in the diagnostic work-up. However, a number of technical issues need to be solved before introducing this as a standard technique. METHODS: Tumor specimens from 122 patients with de novo stage II-IV disease, adequately treated with anthracycline-containing chemotherapy regimens were collected. Immunohistochemical expression of BCL6, CD10, and MUM-1/IRF4 was examined using a tissue microarray (TMA) technique. BCL6 and CD10 were also evaluated on whole tissue sections. RESULTS: Due to profound tissue heterogeneity, BCL6 showed a wide range of positivity, with a high number of false negative results by TMA (25% positive), compared to 53% on whole tissue sections (WTS). CD10 was more homogeneously expressed, and TMA results corresponded better to WTS. Consequently, the results from categorization into GC and non-GC DLBCL differed considerably by use of the two methods, and resulted in very different outcome in terms of overall survival. CONCLUSION: Immunohistochemical GC-status determined on TMA is not reliable enough to be used for individual treatment decisions in DLBCL, mostly due to difficulties in interpreting BCL6 status.

Gene expression profiles relate to SS18/SSX fusion type in synovial sarcoma.

We applied 27k spotted cDNA microarray slides to assess gene expression profiles in 26 samples from 24 patients with synovial sarcomas (SS). The data were analyzed in relation to histopathologic type, cytogenetic aberrations, gene fusion type and development of distant metastases. Supervised analysis based on gene fusion type in 12 SS with SS18/SSX1 and 9 with SS18/SSX2 revealed significant differences in gene expression profiles. Among the discriminators were several genes that have previously been found to be upregulated in SS, including AXL, ZIC2, SPAG7, AGRN, FOXC1, NCAM1 and multiple metallothioneins. Histopathology and degree of cytogenetic complexity did not significantly influence expression, whereas a genetic signature that related to development of metastases could be discerned, albeit with a high false-positive rate. In conclusion, our findings demonstrate differentially expressed genes for the 2 major gene fusion variants in SS, SS18/SSX1 and SS18/SSX2, and thereby suggest that these result in different downstream effects.

Autoimmune and chronic inflammatory disorders and risk of non-Hodgkin lymphoma by subtype.

BACKGROUND: Some autoimmune and chronic inflammatory disorders are associated with increased risks of non-Hodgkin lymphoma (NHL). Because different NHL subtypes develop at different stages of lymphocyte differentiation, associations of autoimmune and inflammatory disorders with specific NHL subtypes could lead to a better understanding of lymphomagenic mechanisms. METHODS: In a population-based case-control study in Denmark and Sweden, 3055 NHL patients and 3187 matched control subjects were asked about their history of autoimmune and chronic inflammatory disorders, markers of severity, and treatment. Logistic regression with adjustment for study matching factors was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for NHL overall and for NHL subtypes. RESULTS: Risks of all NHL were increased in association with rheumatoid arthritis (OR = 1.5, 95% CI = 1.1 to 1.9), primary Sjögren syndrome (OR = 6.1, 95% CI = 1.4 to 27), systemic lupus erythematosus (OR = 4.6, 95% CI = 1.0 to 22), and celiac disease (OR = 2.1, 95% CI = 1.0 to 4.8). All of these conditions were also associated with diffuse large B-cell lymphoma, and some were associated with marginal zone, lymphoplasmacytic, or T-cell lymphoma. Ever use of nonsteroidal anti-inflammatory drugs, systemic corticosteroids, and selected immunosuppressants was associated with risk of NHL in rheumatoid arthritis patients but not in subjects without rheumatoid arthritis. Also, multivariable adjustment for treatment had little impact on risk estimates. Psoriasis, sarcoidosis, and inflammatory bowel disorders were not associated with increased risk of NHL overall or of any NHL subtype. CONCLUSIONS: Our results confirm the associations between certain autoimmune disorders and risk of NHL and suggest that the associations may not be general but rather mediated through specific NHL subtypes. These NHL subtypes develop during postantigen exposure stages of lymphocyte differentiation, consistent with a role of antigenic drive in autoimmunity-related lymphomagenesis.