The risk of developing non-Hodgkin lymphoma and the mortality rate in primary Sjögren's syndrome: a single-centre, retrospective cohort study.

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease that is manifested by the sensation of dry eyes and dry mouth. The higher incidence of non-Hodgkin lymphoma (NHL) among pSS has already been extensively researched. However, there are uncertanties whether the mortality risk in pSS patients and in pSS patients with NHL is increased. The purpose of this study was to describe the prevalence of NHL among pSS patients and to calculate their mortality risk. We retrospectively analysed data on 1367 patients treated in our rheumatology department under the ICD-10 code M35.0. The study finally recruited 155 patients who met the 2016 ACR/EULAR criteria for the diagnosis of pSS. Descriptive statistics was used in data analysis. We applied the indirect standardization by age to compare the incidence rate of NHL in our cohort to general population. Additionally, we compared the mortality in our study to the general population by calculating the standardized mortality ratio (SMR). The overall incidence rate of NHL was 440 per 100,000 patient-years. The SIR compared to the general population was 30.13 (95% CI 12.87-54.63). The overall mortality rate of pSS patients in our cohort was nearly identical to that of the general population (SMR = 0.98 [95% CI (0.47-1.69)]). This study confirms that there are significant differences in lymphoma prevalence, histology, and prognosis across the studied populations. Furthermore, this study found that patients with pSS have similar mortality risk as the general population, and no patient in our cohort died from NHL.

1,3-Butadiene, styrene and lymphohaematopoietic cancers among North American synthetic rubber polymer workers: exposure-response analyses.

OBJECTIVE: To evaluate exposure-response between 1,3-butadiene, styrene and lymphohaematopoietic cancers in an updated cohort of workers at six North American plants that made synthetic rubber polymers. METHODS: Employees were followed from 1943 through 2009 to determine mortality outcomes. Cox regression analyses estimated rate ratios (RRs) and 95% CIs by quartile of cumulative exposure to butadiene or styrene, measured in parts per million-years (ppm-years), and exposure-response trends for all leukaemia, lymphoid leukaemia, myeloid leukaemia, acute myeloid leukaemia, non-Hodgkin's lymphoma (NHL), multiple myeloma and all B-cell malignancies. RESULTS: Among 21 087 workers, adjusted RRs for butadiene and all leukaemia (132 deaths) rose with increasing exposure, with an RR of 2.53 (95% CI 1.37 to 4.67) in the highest exposure quartile (≥363.64 ppm-years), and the exposure-response trend was statistically significant for all leukaemia (p=0.014) and for lymphoid leukaemia (52 deaths, p=0.007). Styrene exposure-response trends for all leukaemia and lymphoid leukaemia were less consistent than those for butadiene. Cumulative exposures to butadiene and styrene were not associated consistently with myeloid leukaemias or the B-cell malignancies, NHL and multiple myeloma. CONCLUSIONS: We confirmed a positive exposure-response relationship between butadiene and all leukaemia among workers, most of whom had coexposure to styrene. Results supported an association between butadiene and lymphoid leukaemia, but not myeloid leukaemia, and provided little evidence of any association of butadiene or styrene exposures with major subtypes of B-cell malignancies other than lymphoid leukaemia, including NHL and multiple myeloma.

Febrile neutropenia (FN) and pegfilgrastim prophylaxis in breast cancer and non-Hodgkin's lymphoma patients receiving high (> 20%) FN-risk chemotherapy: results from a prospective observational study.

PURPOSE: Prophylaxis for febrile neutropenia (FN) is recommended for the duration of myelosuppressive chemotherapy in high-risk patients; yet, granulocyte-colony-stimulating factor (G-CSF) discontinuation occurs frequently in clinical practice. The objective of this study was to investigate the incidence of FN in real-world settings and the extent and impact of early pegfilgrastim discontinuation. METHODS: This prospective, observational study enrolled patients with any-stage non-Hodgkin's lymphoma (NHL) or breast cancer initiating a new chemotherapy course with a high (> 20%) FN risk, with pegfilgrastim in cycle 1. During routine clinical visits, data were collected on FN events, discontinuation of pegfilgrastim (defined as administration of G-CSF other than pegfilgrastim for ≥ 1 cycle) and all G-CSF (and reasons), neutropenic complications and adverse drug reactions (ADRs). RESULTS: Overall, 943 patients were enrolled; 844 met the eligibility criteria (full analysis set) and 814 (86%) completed the study. Twenty-eight patients (3%) had 31 FN events (NHL, n = 17; breast cancer, n = 11). Twenty-six patients (3%) discontinued pegfilgrastim. Forty-four patients (5%) discontinued G-CSF. The most common reason for pegfilgrastim discontinuation was physician preference for daily G-CSF (n = 14 [2%]), and for discontinuation of all G-CSFs was reduced FN risk (n = 14 [2%]). Patients who continued G-CSF prophylaxis were less likely to experience neutropenic complications (odds ratio [95% confidence interval]: 0.26 [0.09-0.80]). Suspected ADRs to pegfilgrastim occurred in 43 patients (5%) and serious ADRs in 5 (1%). CONCLUSIONS: FN rates were consistent with previous reports with pegfilgrastim in clinical practice. No new ADRs were observed. G-CSF discontinuation was uncommon but appeared to increase the likelihood of neutropenic complications.

Incidence of interstitial pneumonitis in non-Hodgkin's lymphoma patients receiving immunochemotherapy with pegylated liposomal doxorubicin and rituximab.

Pneumonitis is a rare but severe and potentially fatal adverse effect in chemotherapy of lymphoma. This study is aimed to investigate the incidence of interstitial pneumonitis in non-Hodgkin's lymphoma (NHL) patients receiving immunochemotherapy with pegylated liposomal doxorubicin and rituximab. Lymphoma patients were retrospectively reviewed, and eligible patients were included in this study. According to the chemotherapy regimens, patients were classified in four groups: combination of vincristine, cyclophosphamide, doxorubicin, and prednisone (CHOP group) with rituximab (RCHOP group) and combination of vincristine, cyclophosphamide, pegylated liposomal doxorubicin and prednisone (CDOP group) with rituximab (RCDOP group). Incidence and severity of interstitial pneumonitis were compared among the four groups. Among 757 patients reviewed, 207 patients were included in final analysis. Thirteen patients developed chemotherapy-induced interstitial pneumonitis, and the mean cycle of chemotherapy before the onset of pneumonitis was 4. Incidence rates of pneumonitis were 0, 1.8, 17.4, and 21.1% in CHOP, RCHOP, CDOP, and RCDOP groups, respectively (p < 0.001). The mean grades of pneumonitis were 0, 2, 2.5, and 3 in four groups, respectively (p < 0.001). After adjustment of confounders, chemotherapy regimens (OR 3.491, 95% CI 1.527-7.981, p = 0.003) and neutropenia in previous cycles (OR 2.186, 95% CI 1.281-3.731, p = 0.004) were independently associated with the incidence of pneumonitis. Interstitial pneumonitis should be highlighted in NHL patients who received more than 4 cycles of RCDOP chemotherapy regimen, especially in those who had grade 4 neutropenia in the previous cycles of chemotherapy.

Periodontal disease and risk of non-Hodgkin lymphoma in the Health Professionals Follow-Up Study.

Periodontal disease is a chronic inflammatory condition that has been associated with chronic diseases, including cancer. In an earlier prospective cohort analysis within the Health Professionals Follow-Up Study (HPFS), we observed a 31% higher risk of non-Hodgkin lymphoma (NHL) among participants with severe periodontal disease at baseline. Here, we extend the study with an additional 8 years of follow-up, and conduct analyses with updated periodontal disease status and NHL subtypes. The HPFS is an ongoing prospective cohort study of 51,529 men in the USA Between baseline in 1986 and 2012, 875 cases of NHL were diagnosed, including 290 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 85 diffuse large B-cell lymphomas and 91 follicular lymphomas. We performed multivariable Cox proportional hazards regression to evaluate associations of interest. History of periodontal disease at baseline was positively associated with risk of NHL overall (hazard ratio (HR) = 1.26, 95% confidence interval (CI): 1.06-1.49) and CLL/SLL (HR = 1.41, 95% CI: 1.04-1.90). With updated periodontal status, HRs were 1.30 (95% CI: 1.11-1.51) for NHL overall and 1.41 (95% CI: 1.08-1.84) for CLL/SLL. In contrast, after adjusting for periodontal disease, tooth loss was inversely associated with NHL, suggesting that other causes or consequences of tooth loss may have different implications for NHL etiology. Our findings suggest that periodontal disease is a risk factor for NHL. Whether periodontal disease is a direct or indirect cause of NHL, or is a marker of underlying systemic inflammation and/or immune dysregulation, warrants further investigation.

Mucositis care in acute leukemia and non-Hodgkin lymphoma patients undergoing high-dose chemotherapy.

PURPOSE: This study intends to provide new insights into the incidence and care of mucositis by the epidemiological characterization of patients with hematological malignancy treated at our institution. It also aims to understand the effectiveness of several treatments used. METHODS: This is a longitudinal observational single-center study-convenience sample-which includes malignant hematologic inpatients submitted to high-dose CT from February to August 2012. We registered epidemiological data, diagnosis, oral mucositis daily questionnaire (OMDQ), World Health Organization (WHO) oral toxicity scale, and supportive medications used for mucositis. RESULTS: We evaluated 30 patients who had 73 episodes of hospitalization, having recorded the development of mucositis in 21.9 % (n = 16) episodes (22 patients with acute leukemia (AL) and 8 patients with non-Hodgkin lymphoma (NHL)). Grades 3-4 mucositis was reported in 4.1 % of the total episodes. The results of OMDQ showed some limitations in the quality of life, of patients with mucositis, related with the ability to eat and drink due to mouth pain (p < 0.001). In patients with NHL and AL, neutropenia entails an increased risk of mucositis (p < 0.001). Patients who did not initiate early prophylaxis with conservative measures developed mucositis earlier (p < 0.05). CONCLUSIONS: The incidence of mucositis is high, being reported mainly in AL patients, with limitations in quality of life. Grade 4 neutropenia increases mucositis risk. Early prophylaxis with basic oral care may delay mucositis. Further studies are crucial to characterize mucositis epidemiology, physiopathology, and its management.

Incremental health care expenditures for non-Hodgkin lymphoma in comparison with other cancers: Analysis of national survey data.

BACKGROUND: Non-Hodgkin lymphoma (NHL) is among the most common cancers in the United States, with an estimated annual incidence of more than 80,000 and a high survival rate. However, limited national data exist regarding the health care burden of NHL. OBJECTIVE: To evaluate the incremental health care expenditures among patients with NHL using the Medical Expenditure Panel Survey (MEPS) data compared with patients with other cancers. METHODS: This observational cross-sectional study included all patients with NHL (≥ 18 years) and all individuals diagnosed with other cancers from the MEPS 2014-2019. The components of health care expenditures included hospital inpatient care, office-based visits, outpatient care, emergency department, prescription medications, dental, home health, and other expenditures. Patients with NHL and those diagnosed with other cancers were identified from the full-year consolidated MEPS Household Component 2014-2019. Descriptive weighted analysis was used to compare the health care expenditure components between individuals with NHL and all other cancers. A 2-part model using probit and generalized linear models with a log link function was used to estimate the incremental increase in total health care expenditures for NHL compared with all other cancers. RESULTS: According to the MEPS, there were 0.74 million patients with NHL (95% CI = 0.62-0.86) and 27.91 million patients with other cancers (95% CI = 26.69-29.13) annually. Most of the patients with NHL were White (78.36%), male (60.67%), and older than 65 years (45.8%). The unadjusted analysis indicated a total annual expenditure of $21,698 (95% CI = $16,752-$26,645) for NHL, which was significantly higher than the annual expenditure for patients with other cancers ($15,029 [95% CI = $14,476-$15,582]). Most of the total health expenditure of both the NHL group and the other cancers group was distributed in 3 categories of hospital inpatient care (29.15% vs 26.29%), office-based visits (28.10% vs 25.08%), and prescription medications (19.03% vs 22.57%). Based on the 2-part model adjusted for all covariates, the annual health care expenditure for NHL was $7,284 (95% CI = $1,432-$13,135), higher than the expenditure of patients diagnosed with all other cancers. Among the health care expenditure components, the office-based visits were $2,641 higher for patients with NHL compared with the other cancers group (95% CI = $1,129-$4,153). CONCLUSIONS: The economic burden of NHL is higher compared with other cancers. Most of the NHL expenditures were attributable to hospital inpatient services and office-based visits. The study findings can inform value-based care considerations because of a better understanding of utilization and care patterns for NHL. DISCLOSURES: Dr Aparasu has received research funding from Astellas Inc., Incyte Corp., Gilead, and Novartis Inc. for projects unrelated to the current work. The other authors declare no conflicts of interest for this article. We confirm that this work is original and has not been published elsewhere, nor is it currently under consideration for publication elsewhere.

Oral Malignant Non-Hodgkin Lymphoma: A Retrospective Single-Center Study.

This study aimed to retrospectively evaluate the incidence of oral non-Hodgkin lymphoma (NHL) in patients referred to the Academic Hospital of the Magna Graecia University of Catanzaro from 2002 to 2020. A retrospective single-center study was performed. Patients with a histologically confirmed diagnosis of oral NHL were included. Demographic data and clinical parameters were digitally recorded, focusing on the NHL-specific localization and symptomatology. The study sample was evaluated by analyzing descriptive statistics with absolute and relative frequencies. A total of 26 patients with intraoral NHL were identified with a progressive increase in NHL occurrence during the observation period. Clinical manifestations included swelling/mass (80.7%), eventually associated with pain and ulcerations. The most common localizations were in soft tissues: buccal mucosa (38.4%), tongue (19.2%), gingiva (11.5%), cheek (11.5%). Oral NHL is rare. Clinical manifestations were unspecific, so a misdiagnosis could occur. The extranodal B-cell form of oral NHL, particularly diffuse large B-cell lymphoma, was the most common frequent oral NHL in this southern Italian population, with a progressively increased occurrence in almost 20 years.

Oral and jaw lymphoma in an Iranian population.

INTRODUCTION: Lymphoma is the second most common malignancy of head and neck. Many studies have been carried out in different population groups to detect the subtypes of oral and jaw lymphoma, but such research has not been conducted in Iran. The purpose of this study was to determine the subtypes of oral and jaw lymphoma by immunohistochemistry. MATERIALS AND METHODS: A total of 36 paraffin-embedded blocks (25 males and 11 females) with primary diagnosis of non-Hodgkin lymphoma were studied by immunohistochemical markers according to cellular morphology. RESULTS: The frequencies were diffuse large B-cell (41.1%), low-grade B-cell (35.2%), peripheral T-cell (11.7%), Burkitt (5.8%), and Hodgkin lymphomas (5.8%). The involved sites were salivary gland (26.4%), maxillary bone (23.5%), mandibular soft tissues (17.6%), maxillary sinus (14.7%), mandibular bone (8.8%), tonsils and tongue (5.7%), and lip and vestibule (2.9%), and 2 cases (5.5%) turned out to be undifferentiated carcinomas. The most common lymphomas in male and females were diffuse large B-cell and low-grade B-cell lymphomas, respectively. CONCLUSIONS: The epidemiology of different types of oral lymphoma in a sample of Iranian population was not similar with other populations of the world. Immunohistochemistry and molecular methods are required to prove the diagnosis in addition to typing of lymphoma.

Conversion to supportive care with biosimilar pegfilgrastim-cbqv enables budget-neutral expanded access to R-CHOP treatment in non-Hodgkin lymphoma.

This pharmacoeconomic simulation (1) assessed the cost-efficiency of converting a panel of 20,000 patients at risk of chemotherapy-induced (febrile) neutropenia (CIN/FN) from reference pegfilgrastim to biosimilar pegfilgrastim-cbqv; (2) estimated how savings can be used to provide budget-neutral expanded access to R-CHOP therapy for non-Hodgkin lymphoma patients; and 3) determined the number-needed-to-convert (NNC) to purchase one additional dose of R-CHOP (US payer perspective). Model inputs included biosimilar conversion from pre-filled syringe [PFS] or on-body injector [OBI] reference pegfilgrastim; age-proportional blended costs for reference pegfilgrastim PFS and OBI, pegfilgrastim-cbqv and R-CHOP; medication administration costs; biosimilar conversion rates of 10-100 %; and 1-6 cycles of prophylaxis. Cost-savings were used to estimate the number of doses of R-CHOP that could be purchased and the NNC to purchase one additional dose. Converting a panel of 20,000 patients requiring CIN/FN prophylaxis to biosimilar pegfilgrastim-cbqv from a low of 1 cycle and 10 % conversion to a high of 6 cycles and 100 % conversion yielded savings from $1,567,195 to $96,668,126. The budget-neutral acquisition of R-CHOP doses afforded by these savings ranged from 227 to 13,999 doses, the latter enabling 2333 patients to receive 6 cycles of R-CHOP treatment with no additional cost to the payer. These results are achieved if all 20,000 panel patients requiring GCSF support are prophylacted with biosimilar pegfilgrastim-cbqv for 6 cycles, yielding an NNC of 1.43 patients per additional R-CHOP dose. This simulation underscores the clinic-economic benefit of prophylaxis with biosimilar growth factor and pegfilgrastim-cbqv specifically.

Cancer risk in patients hospitalised for Graves' disease: a population-based cohort study in Sweden.

BACKGROUND: The possibility of an association of Graves' disease (GD) with subsequent cancers raised by certain studies. METHODS: Using a database on 18 156 hospitalised GD patients, subsequent cancers were ascertained. RESULTS: Increased risks of thyroid and parathyroid tumours were limited to the early follow-up period, which is probably a surveillance bias. Cancer sites with observed excess included the mouth and breast, in contrast to decreased risks of colon cancer, melanoma and non-Hodgkin's lymphoma. CONCLUSION: Increased subsequent cancers in GD patients appeared to be balanced by decreased risks at other sites; chance cannot be excluded.

Blood transfusion, anesthesia, surgery and risk of non-Hodgkin lymphoma in a population-based case-control study.

The incidence of NHL has increased dramatically since at least the 1950s, and during this timeframe there has been a major increase in the use of blood transfusions, invasive surgical procedures and anesthesia, all of which can impact immune function. We evaluated these factors with NHL risk in a population-based study of 759 cases and 589 frequency-matched controls. Risk factor data were collected during in-person interviews. Unconditional logistic regression was used to estimate ORs and 95% CIs, adjusted for the matching factors. History of transfusion was associated with a 26% higher risk of NHL (95% CI 0.91-1.73), and the elevated risk was specific to transfusions first given 5-29 years before the reference date (OR = 1.69; 95% CI 1.08-2.62) and transfusions given for a medical condition (OR = 2.09; 95% CI 1.03-4.26). The total number of surgeries and dental procedures (OR = 1.53 for 26+ surgeries compared to 0-6; 95% CI 1.02-2.29) and to a lesser extent the total number of exposures to general or local/regional anesthesia (OR = 1.35 for 24+ times compared to 0-6; 95% CI 0.91-2.02) were positively associated with risk of NHL. Inclusion of transfusion and surgery or transfusion and anesthesia in the same model did not attenuate these associations. All results were broadly consistent for both DLBCL and follicular subtypes. Blood transfusions were associated with NHL risk, but appear to be a marker for underlying medical conditions. Multiple surgical procedures and/or repeated administration of anesthesia have not been previously reported to be associated with risk of NHL and these exposures warrant further evaluation.

Denis Parsons Burkitt, FRSM, FRCS (Edinburgh): a passion for learning.

Dennis Parsons Burkitt was an accomplished Irish surgeon who was headed for a life of luxury. However, he opted for a more meaningful calling and pursued missionary work in Africa instead. While there, he came across an extraordinary pediatric jaw tumor that was not only disfiguring, but also rapidly fatal. Despite the futility of surgery, he became captivated with studying this unrecognized malignancy and conducted what is considered to be one of the most formidable epidemiologic investigations in the history of cancer research by surveying the entire continent. Without any formal training in research, it would be his simple passion to learn that led him to unravel the mysteries behind a new form of non-Hodgkin lymphoma that currently bears his name. Through his spirit for collaboration, effective forms of treatment were ultimately discovered for this most common pediatric malignancy in Africa.

Survey of neoplasia in red kangaroos (Macropus rufus), 1992-2002, in a zoological collection.

An increase in the proportion of cases with neoplasia observed in a collection of captive red kangaroos (Macropus rufus) when compared with historical records and the paucity of reported neoplasms in kangaroos in the literature prompted a 10-yr review of all red kangaroo necropsies. Individual necropsy, medical, and inventory records for all kangaroos at the Kansas City Zoo were reviewed for the period 1 January 1992 to 31 December 2002. Two squamous cell carcinomas of the oral cavity, two mammary gland adenocarcinomas, a multicentric T-cell lymphosarcoma, and one submucosal pyloric lipoma were diagnosed in six of 28 kangaroo deaths. Three neoplasms were diagnosed antemortem. Four of the six neoplasms were considered malignant, and all four had metastasized. The mean age at death was 11 yr. All six animals with neoplasms were female; however, the exhibit population was composed solely of females. Only 11 cases of neoplasia in red kangaroos have been reported in the literature. On the basis of these cases and a review of the literature, the most commonly observed neoplasms in red kangaroos are mammary gland adenocarcinomas and oral squamous cell carcinomas. Common denominators were not identified in these cases, although chronic gingivitis could have been a contributing factor in the development of the oral squamous cell carcinomas.

Occupation and malignant lymphoma: a population based case control study in Germany.

AIMS: To identify occupations suspected to be associated with malignant lymphoma and to generate new hypotheses about occupational risks in a multicentre, population based case control study. METHODS: Male and female patients with malignant lymphoma (n = 710) aged 18-80 years of age were prospectively recruited in six study regions in Germany. For each newly recruited lymphoma case, a sex, region, and age matched control was drawn from the population registers. Odds ratios and 95% confidence intervals for major occupations and industries were calculated using conditional logistic regression analysis, adjusted for smoking (in pack-years) and alcohol consumption. Patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis. RESULTS: The following economic/industrial sectors were positively associated with lymphoma: food products, beverages, tobacco; paper products, publishing and printing; and metals. Chemicals; real estate, renting, and business activities were negatively associated with lymphoma diagnosis. The authors observed an increased overall lymphoma risk among architects; maids; farmers; glass formers; and construction workers. Shoemaking and leather goods making was negatively associated with the lymphoma diagnosis (although based on small numbers). In the occupational group analysis of lymphoma subentities, Hodgkin's lymphoma was significantly associated only with rubber and plastic products making; diffuse large B cell lymphoma risk was considerably increased among metal processors; follicular lymphoma showed highly significant risk increases for several occupational groups (medical, dental, and veterinary workers; sales workers; machinery fitters; and electrical fitters); and multiple myeloma showed a particularly pronounced risk increase for farmers as well as for agriculture and animal husbandry workers. CONCLUSIONS: The results partly confirm previously defined occupational risks. Occupational risk factors for follicular lymphomas might differ from the overall risk factors for malignant lymphoma.

Predominance and characteristics of Burkitt lymphoma among children with non-Hodgkin lymphoma in northeastern Brazil.

The purpose of this paper was to define the histologic distribution, clinical features, and treatment response of childhood non-Hodgkin lymphoma (NHL) in northeastern Brazil. We reviewed medical records and histopathologic studies of 98 children treated for NHL from 1980 to 1987 at a major pediatric cancer center in Recife, Brazil. Treatment outcome was evaluated in relation to tumor burden (stage and serum LDH) and type of therapy (LSA2L2 vs other multiagent chemotherapy). There was a striking predominance of the small noncleaved cell (Burkitt) subtype, which occurred in 92 of the 98 children and adolescents diagnosed with NHL. Subsequent analyses focused on these patients. The majority (n = 84) had advanced (stage III/IV) disease at diagnosis. The abdomen was the most common site of disease (84 cases); jaw involvement was rare (three cases). Five-year event-free survival (excluding treatment refusals) was significantly better for patients with limited vs advanced stage disease (75 +/- 14% vs 42 +/- 6%; P < 0.04). Elevated serum LDH (>500 U/l) was associated with a poorer outcome (P = 0.008). The type of chemotherapy did not affect EFS (P = 0.95). Only 39% of patients are long-term survivors, reflecting the high rate of septic deaths (25% of patients) and parental refusal/abandonment of therapy (10%). Epstein-Barr virus (EBV) was detected in tumor cells from eight of the 11 cases studied. In clinical presentation, these cases resemble sporadic Burkitt lymphoma, yet in their apparent responsiveness to LSA2L2 therapy and association with EBV, they do not. Childhood NHL in northeastern Brazil is predominantly of the Burkitt subtype, and is associated with clinical features that appear to distinguish it from the endemic and sporadic forms of this tumor. These cases may represent a third or intermediate subtype of Burkitt lymphoma.

Insect repellents, phenoxyherbicide exposure, and non-Hodgkin's lymphoma.

OBJECTIVE: We sought to test a hypothetical explanation of contradictory results in studies of phenoxyherbicides and NHL, that the exposure of rubber gloves recommended for use by farmers when mixing or applying pesticides simultaneously to 2,4-D (2,4-dichlorophenoxyacetic acid), DEET (N,N-diethyl-m-toluamide), and ultraviolet rays increased their permeability to 2,4-D. METHODS: We conducted a case (NHL n = 513)/control (n = 1506) study among men using age; province of residence; exposure to insect repellents containing DEET, phenoxy-herbicides, or dicamba; and gloves when handling pesticides. RESULTS: Using conditional logistic regression, the stratum with reported exposure to mecoprop, to DEET and the use of rubber gloves had higher odds ratios (3.86; 95% confidence interval = 1.57-9.49) compared with strata with other combinations. CONCLUSIONS: In conclusion, the etiologic complexity of NHL was demonstrated.

The malignant lymphomas of Kenya: morphology, immunophenotype, and frequency of Epstein-Barr virus in 73 cases.

Recent information is limited regarding pathological features of the malignant lymphomas of Africa, other than Burkitt's lymphoma. In this study, we apply modern techniques and nomenclature to classify 73 lymphomas from a central histopathology laboratory serving 40 mission hospitals in Kenya. We were particularly interested in the frequency of recently recognized lymphomas and the incidence of Epstein-Barr virus in various lymphoma subtypes. Malignant lymphomas accounted for 12% of all surgical pathology specimens processed in the laboratory over the 21-month period included in the study. Patient age ranged from 4 to 97 years (median, 35 years). The male-to-female ratio was 2.5:1. Sixty lymphomas (82%) were non-Hodgkin's, and 13 (18%) were Hodgkin's disease. Of the non-Hodgkin's lymphomas (NHLs), 52 (87%) were B-lineage, including 21 (35% of NHLs) Burkitt's lymphomas (only one from the jaw), 11 (18%) diffuse large B cell lymphomas; nine (15%) small lymphocytic lymphomas, six (10%) Burkitt's-like lymphomas, two (3%) follicular lymphomas (two of two expressed bcl-2 protein; one of two showed bcl-2 major breakpoint region rearrangement), two (3%) mantle cell lymphomas, and one extranodal marginal zone lymphoma. Of the eight T cell lymphomas, six were precursor T-cell type, and the remaining two were peripheral T cell lymphomas, unspecified. The median age of the 13 patients (18% of lymphomas) with Hodgkin's disease was 23 years (range, 9 to 97 years). Six were nodular sclerosis, four were mixed cellularity, one case each was lymphocyte depletion, lymphocyte predominance, and unclassified Hodgkin's disease. Hodgkin's cells in 6 of the 12 nonlymphocyte predominance cases were positive for CD20, and in three of the six for CD45 as well. Epstein-Barr virus was identified using in situ hybridization for EBER 1 in the malignant cells of 22 of 39 informative lymphomas, including each of 17 Burkitt's lymphomas, and three of seven diffuse large B cell lymphomas. Of note, none of five Burkitt's-like lymphomas expressed EBER 1. One of two informative cases of peripheral T cell lymphoma, and four of nine cases of Hodgkin's disease were EBER 1 positive. In summary, T cell lymphomas and recently recognized B-lineage non-Hodgkin's lymphoma subtypes do not appear to be particularly common in East Africa.