恶性淋巴瘤1126例临床特点分析

 目的　分析恶性淋巴瘤患者住院的临床特点。方法　从该院病案数据库提取2005年1月至2009年12月住院恶性淋巴瘤患者的资料,剔除未能明确病理分型及重复入院的病例,从年龄、性别、病理类型、肿瘤起病部位及分期等方面进行分析、总结。结果　住院的恶性淋巴瘤患者1126例,男女比例为1.94∶1。霍奇金淋巴瘤（HL）患者年龄集中在20～40岁,以混合细胞型（64.16 %）、结节硬化型（29.48 %）为主。非霍奇金淋巴瘤（NHL）患者年龄以50~70岁为多,发病率位于前10位的为弥漫大B细胞淋巴瘤（53.31 %）、结外NK／T细胞淋巴瘤（7.35 %）、套细胞淋巴瘤（6.40 %）、B细胞慢性淋巴细胞白血病／小淋巴细胞淋巴瘤（4.30 %）、间变性大细胞淋巴瘤（4.09 %）、前T细胞淋巴母细胞白血病／淋巴瘤（3.88 %）、外周T细胞淋巴瘤（非特指）（3.46 %）、血管免疫母细胞型淋巴瘤（3.04 %）、滤泡性淋巴瘤（2.94 %）、伯基特淋巴瘤（2.52 %）。两者起病部位均以颈部淋巴结常见。结论　HL和NHL发病存在性别、年龄、病理类型、起病部位等差异。     

淋巴瘤合并结核21例临床分析

 【摘要】　目的　探讨淋巴瘤合并结核的临床特点、可能的发病机制以及有效的治疗手段。方法　回顾分析21例已确诊的淋巴瘤合并结核患者的临床特点、病理特征、确诊手段、治疗及转归情况。结果　21例患者中,淋巴瘤诊断先于结核诊断者6例,其中5例结核感染时淋巴瘤正在化疗;淋巴瘤诊断在结核感染之后诊断者13例,其中10例陈旧性肺结核者有6例在淋巴瘤治疗过程中复燃;二者同时诊断者2例。淋巴瘤患者中霍奇金淋巴瘤6例,非霍奇金淋巴瘤15例。结论　在结核病的高发地区,结核病和淋巴瘤可同时存在于同一患者;合并结核的淋巴瘤患者中霍奇金淋巴瘤构成比高于普通人群淋巴瘤患者的霍奇金淋巴瘤构成比;对于患有陈旧性肺结核的淋巴瘤患者,化疗过程中要密切注意陈旧性肺结核复燃的可能。     

B-cell lymphoma of 708 cases in Japan: incidence rates and clinical prognosis according to the REAL classification

New insights into the pathogenesis of lymphoid malignancies have been gained through novel techniques such as genetic, molecular and immunologic methods. Recently, based on those findings, a new classification system for lymphoid malignancies, known as the REAL classification, has been proposed. To clarify the relation between the histological classification and prognosis of B-cell lymphoid malignancies, we re-classified 708 cases. In all cases, the B-cell phenotype and/or genotype was confirmed by immunohistochemical staining and/or receptor gene analysis. The most common B-cell lymphoma types were diffuse large B-cell lymphoma (58.8%), follicular lymphoma (12.1%), marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) (9.0%) and mantle cell lymphoma (5.9%). Minor types were lymphoblastic lymphoma (3.4%), Burkitt's lymphoma (2.4%), nodal marginal zone lymphoma (2.1%), lymphoplasmacytic lymphoma (2.0%) and plasmacytoma (1.4%). Rare types were prolymphocytic lymphoma and splenic marginal zone lymphoma. Using overall survival rates, the various B-cell lymphoma types could be divided into three broad groups for prognostic purposes: (1) the low risk group consisted of follicular lymphoma, marginal zone lymphoma of MALT, nodal marginal zone lymphoma, plasmacytoma and lymphoplasmacytic lymphoma; (2) the intermediate risk group consisted of diffuse large B-cell lymphoma, Burkitt's lymphoma and mantle cell lymphoma; and (3) the high risk group consisted of lymphoblastic lymphoma. In MALT, the low grade type had a better prognosis than the high grade type. In diffuse large B-cell lymphoma, the common type had a better prognosis than the variant type, which mainly consisted of the immunoblastic lymphoma. The histological classification will have a benefit for the clinical approach.     

A clinicopathologic study of primary small intestine lymphoma: prognostic significance of mucosa-associated lymphoid tissue-derived lymphoma

BACKGROUND: It remains unclear whether the presence of mucosa-associated lymphoid tissue (MALT) lymphoma has prognostic implications for patients with primary small intestine lymphoma. METHODS: The clinicopathologic features of 80 patients with primary small intestine lymphoma were examined retrospectively in relation to the presence of MALT lymphoma. Survival was compared univariately and multivariately among the groups divided by clinicopathologic findings. RESULTS: Twenty-one cases (26%) were diagnosed as low grade B-cell lymphoma (15 marginal zone B-cell lymphoma of MALT type, 2 mantle cell lymphoma, and 4 follicle center lymphoma), 46 cases (58%) were diagnosed as high grade B-cell lymphoma (19 secondary large cell lymphoma with a low grade MALT component, 17 diffuse large cell lymphoma without MALT features, 7 Burkitt lymphoma, and 3 lymphoblastic lymphoma), and 13 cases (16%) were diagnosed as T-cell lymphoma. A significantly better survival was noted for patients without colorectal and/or gastric involvement, diffuse infiltration under macroscopy, high grade histology, and perforation. Those patients with MALT type tumors, less advanced stage of disease, B-cell phenotype, benign lymphoid follicular hyperplasia, and radical tumor resectability appeared to have a better survival rate. Based on Cox multivariate analysis, early stage disease and MALT-derived tumors were determined to be independent prognostic factors (P < 0.05). CONCLUSIONS: The presence of MALT-derived lymphoma appears to have a favorable prognosis among patients with primary small intestinal lymphoma.     

Distribution and prognosis of WHO lymphoma subtypes in Taiwan reveals a low incidence of germinal-center derived tumors

To assess the distribution of lymphomas in Taiwan according to the WHO (World Health Organization) classification, 175 recently diagnosed cases of malignant lymphomas were studied and the clinicopathologic data were analyzed. B-cell lymphomas accounted for 57.1% of cases, T-cell lymphomas 38.9%, and Hodgkin's lymphoma 4%. Extranodal lymphomas predominated (55.4%). The most common subtype of B-cell lymphoma was diffuse large B-cell lymphoma (33.1%). All tumor types believed to be derived from germinal center (GC) B-cells including follicular lymphoma (4.6%), Burkitt lymphoma (1.7%), Hodgkin lymphoma (4.0%), and GC-like diffuse large B-cell lymphoma (as defined by combined expression of bcl-6 and CD10) were rather uncommon as compared to frequencies seen in series from Western countries. The common T-cell lymphomas included nasal and extranasal NK/T cell lymphoma (7.4%), mycosis fungoides (7.4%), and unspecified peripheral T-cell lymphoma (6.9%). Adult T-cell leukemia/lymphoma was very uncommon and accounts for only 0.6%. The proportional increase in T-cell lymphomas that were unrelated to type I human T-cell lymphotropic virus (HTLV-1) may be linked to differential Epstein-Barr virus (EBV) oncogenesis. The survival data revealed that mantle cell lymphoma, NK/T-cell lymphoma, unspecified peripheral T-cell lymphoma, and subcutaneous panniculitis-like T-cell lymphoma had an aggressive course. Our results confirm the utility of the WHO classification scheme for prognostic stratification and further highlight the distinctive distribution pattern of malignant lymphoma in Taiwan including the higher relative incidence of T cell lymphomas and the rarity of germinal center-derived B-cell tumors.     

Recurrent chromosome abnormalities in adult T-cell lymphomas of peripheral T-cell origin

Cytogenetic studies were performed on 11 Japanese patients with adult T-cell lymphoma of peripheral T-cell origin. All patients had a histologic diagnosis of diffuse lymphoma, and were treated with intensive combination chemotherapy; their median survival was 6 months. Lymphomas were categorized on the basis of the classification proposed by the Lymphoma Study Group of Japan: 5 patients had the features of pleomorphic lymphoma; 3, mixed lymphoma; 2, large-cell lymphoma; and 1, medium-sized-cell lymphoma. The modal chromosome number of abnormal cells was near-diploid in 7, and hypotetraploid in 4 including 3 patients with pleomorphic lymphoma. Abnormalities of the clonal chromosomes were observed in all 11 patients. A translocation of the short arm of 19 at band 19p13 was found in 2 patients with pleomorphic lymphoma and in one patient each with mixed lymphoma and medium-sized-cell lymphoma. A translocation of the short arm of 14, with a break at band 14p12, occurred in 4 patients with pleomorphic lymphoma. In one patient each with mixed lymphoma and large-cell lymphoma, an extra chromosome 3 was found. The numerical change was unique because their lymphomas were further categorized as "angioimmunoblastic lymphadenopathy with dysproteinemia" and "large-cell immunoblastic lymphoma", respectively. Our findings suggest that characteristic chromosome abnormalities occur in adult T-cell lymphoma, and dividing cells in the tetraploid range tend to be predominant in pleomorphic lymphoma.     

Diagnostic difficulties of pure intrasinusoidal bone marrow infiltration of non-Hodgkin's lymphoma: a report of eight cases from India

Bone marrow involvement in non-Hodgkin's lymphoma is prognostically important for appropriate management. Intrasinusoidal pattern of bone marrow infiltration is poorly identified on trephine biopsies. We analyzed the clinical, hematological and histopathological spectrum of eight cases of non-Hodgkin's lymphoma showing pure intrasinusoidal bone marrow infiltration. Fever, cytopenias and blasts in circulation were the indications for bone marrow aspiration and trephine biopsies. Flow cytometry on bone marrow and immunohistochemistry on trephine sections were done. There were five cases of T-cell hepatosplenic non-Hodgkin's lymphoma (three γδ T-cell lymphoma) and three B-cell non-Hodgkin's lymphoma (two intravascular large B-cell lymphoma and one splenic marginal zone lymphoma). Except the cases with intravascular large B-cell lymphoma, all showed variable splenomegaly without lymphadenopathy. Immunohistochemistry highlighted intrasinusoidal infiltration, which was difficult to discern on hematoxylin and eosin. This brief analysis highlights that pure intrasinusoidal infiltration of extranodal non-Hodgkin's lymphoma requires a high degree of diagnostic suspicion and can be seen in various lymphomas.     

Blastic variant of mantle cell lymphoma following interfollicular Hodgkin's lymphoma

Infrequently, patients are diagnosed with Hodgkin's lymphoma and a morphologically distinct lymphoma. While specific subtypes of lymphomas (including Hodgkin's lymphoma) may present diagnostic difficulties, fine needle aspiration biopsy (FNAB) is sometimes useful in the evaluation and classification of these lymphoproliferative processes. We report a case of the blastic variant of mantle cell lymphoma following Hodgkin's lymphoma, interfollicular variant. A 66-year-old woman with a history of Hodgkin's lymphoma presented with increasing contralateral cervical adenopathy three years after receiving chemotherapy. FNAB with ancillary immunophenotypic characterization identified mantle cell lymphoma, blastic variant. Subsequent excisional biopsy confirmed this diagnosis and also aided in the exclusion of recurrent Hodgkin's lymphoma. In addition to identifying the previously unreported combination of blastic variant of mantle cell lymphoma and Hodgkin's lymphoma, this case emphasizes the utility of FNAB in evaluation of new masses in patient's with a previous diagnosis of Hodgkin's lymphoma.     

原发性胃肠道淋巴瘤的诊断与治疗

目的探讨原发性胃肠道淋巴瘤的临床特点及诊治方法。方法1983年至2004年在北京大学第一医院外科接受治疗的原发性胃肠道淋巴瘤患者35例,对其临床病理资料及预后进行回顾性分析。结果本组原发性胃肠道淋巴瘤术前诊断率仅为20.0%;18例胃淋巴瘤中16例接受手术治疗,其中12例行根治性切除;17例肠道淋巴瘤均手术治疗,其中14例行根治性切除;Ann Ar-bor临床分期为:ⅠE期14例,ⅡE期10例,ⅢE期1例,ⅣE期10例。MALT淋巴瘤与非MALT淋巴瘤在年龄、性别及发病部位及早晚分期上差异无显著性。MALT淋巴瘤组手术根治率(92.9%)高于非MALT淋巴瘤(68.4%),MALT淋巴瘤组淋巴结转移率(42.9%)明显低于非MALT淋巴瘤组(84.2%)。结论胃肠道淋巴瘤临床表现缺乏特异性,术前诊断率低;胃淋巴瘤与肠淋巴瘤在性别、年龄、手术根治性及临床分期方面无明显区别;MALT淋巴瘤组确诊时分期较早,手术根治率高,淋巴结转移率低,预后优于非MALT淋巴瘤组。外科手术是诊断和治疗原发性胃肠道淋巴瘤的主要方法。     

淋巴瘤单发骨病变的18F－FDGPET／CT影像学分析

目的：研究原发性骨淋巴瘤与单发继发性淋巴瘤骨髓浸润的18 F －FDG PET／CT 影像学表现,探讨18 F－FDG PET／CT 对原发性骨淋巴瘤的诊断及鉴别诊断价值。方法：回顾性分析经病理证实的25例单发骨淋巴瘤的18 F －FDG PET／CT 影像学资料。结果：25例骨淋巴瘤均为单发,其中14例位于脊柱骨,10例位于附肢骨,1例位于肋骨。15例为原发性骨淋巴瘤,10例为继发性淋巴瘤骨髓浸润。原发性骨淋巴瘤15例中非霍奇金淋巴瘤11例,霍奇金淋巴瘤4例;继发性淋巴瘤骨髓浸润10例中非霍奇金淋巴瘤7例,霍奇金淋巴瘤3例。25例骨淋巴瘤中23例 CT 表现为骨质密度异常改变,2例病变骨质密度未见明显异常改变。病变 FDG摄取不同程度增高,SUVmax范围为2．6～24．5。原发性骨淋巴瘤及继发性淋巴瘤骨髓浸润病变 SUVmax经 Mann－Whitney U 检验提示原发性骨淋巴瘤与继发性淋巴瘤骨髓浸润病变 SUVmax有差异（P ＝0．007）。结论：原发性骨淋巴瘤18 F －FDG PET／CT 影像学表现有一定的特征性,分析其表现对原发性和继发性骨淋巴瘤的诊断及鉴别诊断有一定的临床价值。     

The genetics of familial lymphomas

Whereas familial clustering of malignant lymphoma is well documented, the molecular changes underlying familial lymphoma syndromes remain unclear. An understanding of the hereditary basis of lymphoma may lead to the identification of new molecular markers for disease or novel therapeutic targets. This paper reviews the genetics of familial lymphoma, focusing on germline susceptibilities to lymphoma as well as germline susceptibilities to environmental exposures that have been linked to lymphoma.     

A Reappraisal of the Diagnostic and Therapeutic Management of Uncommon Histologies of Primary Ocular Adnexal Lymphoma

Lymphoma is the most common malignancy arising in the ocular adnexa, which includes conjunctiva, lachrymal gland, lachrymal sac, eyelids, orbit soft tissue, and extraocular muscles. Ocular adnexal lymphoma (OAL) accounts for 1%–2% of non‐Hodgkin lymphoma and 5%–15% of extranodal lymphoma. Histology, stage, and primary localizations are the most important variables influencing the natural history and therapeutic outcome of these malignancies. Among the various lymphoma variants that could arise in the ocular adnexa, marginal zone B‐cell lymphoma (OA‐MZL) is the most common one. Other types of lymphoma arise much more rarely in these anatomical sites; follicular lymphoma is the second most frequent histology, followed by diffuse large B‐cell lymphoma and mantle cell lymphoma. Additional lymphoma entities, like T‐cell/natural killer cell lymphomas and Burkitt lymphoma, only occasionally involve orbital structures. Because they are so rare, related literature mostly consists of anecdotal cases included within series focused on OA‐MZL and sporadic case reports. This bias hampers a global approach to clinical and molecular properties of these types of lymphoma, with a low level of evidence supporting therapeutic options. This review covers the prevalence, clinical presentation, behavior, and histological and molecular features of uncommon forms of primary OAL and provides practical recommendations for therapeutic management.     

青海地区淋巴瘤253例临床特点与预后因素分析

目的 分析淋巴瘤的临床特点及预后相关因素.方法 对青海地区253例淋巴瘤患者临床资料进行回顾性研究并随访.采用Kaplan-Meier法分析患者不同临床特点及实验室检查的生存期差异.采用Cox比例风险回归模型分析影响预后的因素.结果 253例淋巴瘤患者中,男、女比例为1.56∶1,中位年龄为48岁,发病年龄高峰为40岁和60岁左右.结内起病（56.13％）较多,结外起病常见部位为鼻咽部和胃肠道.病理类型为霍奇金淋巴瘤40例（15.81％）,非霍奇金淋巴瘤213例（84.19％）.前者以结节硬化型（72.50％）最多见;后者中B细胞淋巴瘤148例（69.48％）,最常见的病理类型为弥漫大B细胞淋巴瘤（39.91％）、滤泡细胞淋巴瘤（12.21％）及周围T细胞非特殊型淋巴瘤（9.39％）.单因素预后分析显示,临床分期、有无B症状、血红蛋白（Hb）、乳酸脱氢酶（LDH）、国际预后指数（IPI）及治疗方案与非霍奇金淋巴瘤预后密切相关（均P＜0.05）.Cox回归模型多因素分析显示,临床分期、IPI及治疗方案与非霍奇金淋巴瘤的预后关系密切,差异有统计学意义（均P＜0.05）.结论 青海地区淋巴瘤发病年龄有两个高峰,结内发病高于结外,B细胞淋巴瘤多见,IPI分组适用于该地区非霍奇金淋巴瘤的预后评估,并可作为其独立的预后因素.     

miRNA与淋巴瘤发病机制的研究进展

目的:总结microRNA在淋巴瘤发病机制中的研究进展.方法:应用CNKI期刊全文数据库系统,以“microRNA和淋巴瘤”为关键词,检索2004-2011年文献,共检索到英文文献306篇;纳入标准:1) MicroRNA的一般特性;2)MicroRNA与非霍奇金淋巴瘤发生、发展的关系;3)MicroRNA与霍奇金淋巴瘤发生、发展的关系;根据纳入标准符合分析的文献37篇.结果:MicroRNA在淋巴瘤组织和正常组织中存在差异性表达,既具有抑癌基因的作用,亦可发挥癌基因的作用,参与淋巴瘤细胞的分化、增殖和凋亡,并呈现出MicroRNA介导的网络性调控.结论:MicroRNA在淋巴瘤的发病机制中具有重要作用,有可能为淋巴瘤的诊断和治疗带来新的思路.     

Imaging diagnoses of lymphoma of oropharynx

Objective:To investigate the CT and MRI findings of lymphoma of oropharynx and their clinical values.Methods: CT and MRI findings of 18 cases of lymphoma of oropharynx were analyzed and compared with the operative and pathological findings. Results: 11 cases of lymphoma of the tonsil and 3 cases of lymphoma of the bases of tongue displayed regular soft tissue mass with protuberated into oropharynx. 4 cases of lymphoma of the lateral pharynx displayed irregular soft tissue mass in oropharynx. Their density and signal of the lymphoma were homogeneous and showed slight enhancement by CT and MRI. All lesions did not appear necrosis or cyst. 10 cases of cervical lymphoid metastasis were found in 18 cases of lymphoma of oropharynx.Conclusion: CT and MRI can provide the position,shape and range of lymphoma of oropharynx and metastases in lymph nodes and invasion to surrounding tissues. They had high clinical value in diagnosis and treatment of lymphoma of oropharynx.     

Clinical analysis of 1629 newly diagnosed malignant lymphomas in current residents of Sichuan province,China

Previous studies in other provinces of China (Beijing, Xinjiang, Shanxi, Jiangxi, Shanghai, Guangdong, and Taiwan) suggest that the distributions of lymphoma subtypes differ compared with Western populations. In order to evaluate the characteristics of malignant lymphoma in Sichuan, China, we analyzed case series data from incident lymphoma patients diagnosed in 2008 from three hospitals, including a total of 1629 cases and including only current residents of Sichuan. The median age of diagnosis for cases was 54 years, with a higher proportion of male cases compared with female cases. The most commonly diagnosed subtypes included diffuse large B‐cell lymphoma (40.4%), NK/T‐cell lymphoma (NKTCL; 11.8%), mixed cellularity Hodgkin lymphoma (7.0%), mantle cell lymphoma (4.8%), and marginal zone B‐cell lymphoma (3.9%). Differences in demographic characteristics between Hodgkin lymphoma (HL) and non‐Hodgkin lymphoma (NHL) cases were apparent for median age at diagnosis (HL: 34 years; NHL: 57 years), and NHLs accounted for nearly all (99.3%) of the 931 cases of extranodal lymphoma. These findings indicate a higher proportion of NKTCL cases and a lower proportion of follicular lymphoma cases (2.3%) in these hospitals in Sichuan, relative to reports from some other provinces within China (e.g., Shanghai and Shanxi) and the USA. Copyright © 2015 John Wiley & Sons, Ltd.     

培美曲塞为主的化疗方案治疗中老年非霍奇金淋巴瘤回顾性分析CSCD

目的回顾性分析培美曲塞为主的化疗方案治疗中老年非霍奇金瘤患者的安全性及有效性。方法回顾性收集2016年11月至2018年10月中国医学科学院肿瘤医院收治的以培美曲塞为主的化疗方案治疗的非霍奇金淋巴瘤患者临床资料,并对相关文献进行系统性综述。结果共纳入10例非霍奇金淋巴瘤患者,7例为弥漫大B细胞淋巴瘤,2例为血管免疫母T细胞淋巴瘤,1例为结外NK/T细胞淋巴瘤。肿瘤复发或一线治疗进展后接受培美曲塞为主的化疗方案,弥漫大B细胞淋巴瘤有4例达到部分缓解,3例疾病进展,出现的不良反应主要为Ⅰ~Ⅱ度骨髓抑制及胃肠道反应。结论培美曲塞为主的化疗方案治疗弥漫大B细胞淋巴瘤患者,尤其是原发性中枢神经系统淋巴瘤,可能有一定的有效性,且安全性可控。     

Distribution and clinicopathologic characteristics of non-Hodgkin's lymphoma in India: a study of 935 cases using WHO classification of lymphoid neoplasms (2000)

The frequency of various subtypes of non-Hodgkin's lymphoma (NHL) differs in various regions worldwide. We studied distribution of various subtypes of NHL by using WHO classification of lymphoid neoplasms (2000), immunophenotyping and clinicopathologic characteristics of various histologic subtypes in 935 cases. B- and T-cell NHL constituted 79.3% and 18.8% of cases. Diffuse large B-cell lymphoma (DLBL) was the most common subtype (50.2%). A lower frequency of follicular lymphoma, marginal zone lymphoma and mantle cell lymphoma (MCL) was noted compared to that observed in the developed countries, whereas a lower frequency of peripheral T-cell lymphoma - not otherwise specified (PTCL-NOS) and extranodal NK/T-cell lymphoma was seen compared to that in the other Asian countries. A higher frequency of DLBL and precursor T-lymphoblastic leukemia/lymphoma was noted. Extranodal and bone marrow involvement in MCL and PTCL-NOS was less frequent. Anaplastic variant of DLBL was noted in 21.5% of all DLBLs. Null/T-cell anaplastic large cell lymphoma presented in the older age.     

Natural history of follicular grade 3 non-Hodgkin's lymphoma

PURPOSE OF REVIEW: Follicular lymphoma grade 3 is recognized as a distinct entity in the World Health Organization classification of lymphomas. There is confusion regarding the natural history of these lymphomas, because some studies indicate an indolent behavior and others show more aggressive behavior. This review examines the biological and clinical characteristics of follicular lymphoma grade 3 and compares these characteristics with other lymphomas. RECENT FINDINGS: Several reports suggest that follicular lymphoma grade 3 has molecular and genetic characteristics that distinguish these lymphomas from other grades of follicular lymphoma. These characteristics are often more common in patients with diffuse large B-cell lymphoma than follicular lymphoma. It is impossible to make firm recommendations on management because prospective trials are lacking. Nevertheless, recent studies have demonstrated that follicular lymphoma grade 3 patients treated with anthracycline-based therapy have similar outcomes to patients with diffuse large B-cell lymphoma. SUMMARY: Patients with follicular lymphoma grade 3 should be treated with curative intent. They should receive aggressive anthracycline-based therapy combined with rituximab, which is identical to therapy used for patients with diffuse large B-cell lymphoma.     

Cigarette smoking and risk of non-Hodgkin's lymphoma--a population-based case-control study.

BACKGROUND: Epidemiologic evidence of an association between tobacco smoking and non-Hodgkin's lymphoma has been conflicting. This may reflect that non-Hodgkin's lymphoma comprises several distinct disease entities with different etiologies, as some studies have indicated an association between smoking and follicular lymphoma. OBJECTIVE: To investigate the association between cigarette smoking and non-Hodgkin's lymphoma risk, overall and by subtype. METHODS: As part of a nationwide Danish-Swedish population-based case-control study, we interviewed 3,055 incident non-Hodgkin's lymphoma patients and 3,187 population controls. All lymphomas were uniformly classified according to the WHO classification. We used unconditional logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for the association between cigarette smoking and risk of non-Hodgkin's lymphoma. RESULTS: Cigarette smoking was not associated with the risk of non-Hodgkin's lymphoma overall (OR, 0.97; 95% CI, 0.87-1.08) nor with the major subgroups such as diffuse large B-cell lymphoma (OR, 0.94; 95% CI, 0.79-1.10), chronic lymphocytic leukemia (OR, 0.86; 95% CI, 0.72-1.02), or follicular lymphoma (OR, 1.03; 95% CI, 0.85-1.24). Female smokers were at a marginally increased risk of follicular lymphoma (OR, 1.41; 95% CI, 1.04-1.92). Men who had ever smoked had a significantly increased risk of T-cell lymphoma (OR, 1.67; 95% CI, 1.11-2.51). No dose-response association with cigarette smoking could be established for any lymphoma subgroup. CONCLUSION: We found little evidence of an association between cigarette smoking and non-Hodgkin's lymphoma risk overall. Although increased risks of follicular lymphoma in female smokers and of T-cell lymphoma in male smokers were suggested, no dose-response relationship was observed, leaving limited support for causality.