Intrinsic and treatment-related immune alterations in chronic lymphocytic leukaemia and their impact for clinical practice

Pulmonary Coccidioidomycosis Occurring in a Patient Treated With Acalabrutinib for Chronic Lymphocytic Leukemia

Acalabrutinib is a Bruton tyrosine kinase inhibitor (BTKi) approved for use in the treatment of chronic lymphocytic leukemia (CLL). Herein, we present a patient successfully treated with reduced-dose acalabrutinib for CLL, with pre-existing hypogammaglobulinemia-type immunoglobulin G (IgG) and immunoglobulin M (IgM). Twenty-four months into therapy, he developed a right upper lobe infiltrate due to pulmonary coccidioidomycosis; the Naranjo causality assessment score was 4 (probable). The patient received monthly intravenous IG (IVIG) infusions and antifungal therapy, with significant clinical improvement. Acalabrutinib was restarted, along with close clinical monitoring. The extent to which invasive fungal infections can be attributed to acalabrutinib alone is not always straightforward due to the presence of immune defects associated with CLL, endemic zip codes, and a prior exposure to ibrutinib. Physicians should remain vigilant in assessing and managing invasive fungal infections in these patients in order to optimize patient safety and clinical outcomes.

Severe infections in patients with chronic lymphocytic leukemia included in trials investigating BTK and BCL2 inhibitors

Bruton tyrosine kinase inhibitors (BTKi) and the BCL-2 inhibitor venetoclax have significantly improved the prognosis of patients with chronic lymphocytic leukemia (CLL). However, the incidence of severe infections in patients receiving these agents needs to be better understood. Our review aimed to provide an overview of grade ≥3 infections in patients with CLL who received BTKi and venetoclax-based therapy in prospective trials. Infection rates were influenced by the age of patients and the duration of follow-up. For treatment-naive (TN) patients receiving BTKi, infection rates ranged between 11.4 % and 27.4 % and were close to 30 % in relapsed/refractory (R/R) patients. TN and R/R patients receiving fixed-duration venetoclax-based treatments showed variable rates, with maximum values around 20 %. Opportunistic and fatal infections were uncommon. In conclusion, infections remain a concern in patients with CLL receiving targeted agents. A better definition of factors increasing infection vulnerability could help identify those patients who require infection prophylaxis.

Evaluation of infectious morbidity due to BTK inhibitors in indolent B-cell lymphomas: latest research findings and systematic analysis

INTRODUCTION

Randomized clinical trials (RCTs) have suggested that BTK inhibitors (BTKis) might increase infectious disease (ID) risk. Systematic analysis of this topic as derived from RCTs and clinical practice is needed.

AREAS COVERED

An extensive Medline, Embase, and Cochrane search of peer-reviewed sources reporting on ID morbidity in patients on BTKis was performed (1 January 2014 - 31 December 2023). Contribution of intrinsic immune defects in indolent B-cell lymphomas to this morbidity was carefully considered.

EXPERT OPINION

Patients with indolent B-cell lymphomas display a wide range of innate and adaptive immune defects. In addition, BTKi use is linked with an increased signal of upper respiratory tract infections (URTIs) and pneumonias, mainly grade 1-2. These agents also increase the risk of rare invasive fungal infections (IFIs), mainly due to Cryptococcus and Aspergillus spp. with a peak within several months after the start of therapy. More than half of these IFIs are fatal. Research suggests a similar ID risk across 1st, 2nd and 3rd generations of BTKis, all causing B-cell dysfunction due to BTK inhibition, along with off-target functional neutrophil/macrophage alterations. Expanding the knowledge base on ID morbidity in patients on BTKis would facilitate timely diagnosis and treatment, and improve clinical outcomes.

Outcomes of Hodgkin variant Richter transformation in chronic lymphocytic leukaemia and small lymphocytic lymphoma in British Columbia

Hodgkin variant Richter transformation (HvRT) is a rare and challenging complication of chronic lymphocytic leukaemia (CLL) for which information on prognostic factors and treatment approaches remain limited. We analysed characteristics and survival outcomes of a population-based cohort of 32 patients with HvRT identified in British Columbia over a 40-year period. Median interval from CLL diagnosis to HvRT was 5.6 years (range, 0-33.6), with five cases diagnosed concurrently. Most patients (80%) had treatment for CLL prior to HvRT. Median age at HvRT was 71 years (range, 51-86) and the majority of patients had high-risk disease, including stage 3-4 in 87% and International Prognostic Score (IPS) ≥ 4 in 65%. Two-year progression-free (PFS) and overall survival (OS) from HvRT were 47% (95% CI: 29%-64%) and 57% (95% CI: 38%-72%), respectively. OS from HvRT was significantly worse in those with anaemia (p = 0.02), elevated lactate dehydrogenase (p = 0.04), high IPS (p = 0.04), and worse performance status (p = 0.001). For those treated with curative-intent ABVD/ABVD-like therapy, 2-year PFS and OS were 70% (95% CI: 45%-85%) and 74% (95% CI: 49%-89%), respectively. In this real-world population-based cohort, HvRT was associated with poor clinical outcomes overall; however, those able to tolerate curative-intent therapy had similar survival to older patients with de novo HL.

A fatal disseminated cryptococcal infection in a patient treated with zanubrutinib for Waldenström's macroglobulinemia

INTRODUCTION

Zanubrutinib is a second generation, irreversible small-molecule Bruton tyrosine kinase inhibitor (BTK) approved for the treatment of Waldenström's macroglobulinemia, mantle cell lymphoma, and marginal zone lymphoma. As a class, BTKs have been linked with an increased risk of respiratory infections in clinical trials.

CASE REPORT

We describe a 75-year-old patient who presented with generalized weakness, fevers, dyspnea, and dry cough four months after starting zanubrutinib therapy for Waldenström's macroglobulinemia. He was subsequently diagnosed with pneumonia. Septic work-up led to diagnosis of disseminated cryptococcal infection, complicated by fungal pneumonia and meningitis.

MANAGEMENT AND OUTCOME

Zanubrutinib was held on admission, and the patient was started on combination oral and intravenous antifungal therapy. Despite clearance of fungemia, aggressive resuscitation, and appropriate antimicrobial therapy, respiratory status deteriorated requiring intubation. His condition progressed to septic shock, multiorgan failure, and demise.

DISCUSSION/CONCLUSION

We report herein a case of fatal disseminated cryptococcosis in the setting of zanubrutinib use for Waldenström's macroglobulinemia. At the time of diagnosis, his Waldenström's macroglobulinemia was in a partial response. The mechanism by which Bruton tyrosine kinase inhibitors (BTKs) lead to invasive fungal infections in these patients remains to be explored. T- and B-cell immune defects accompanying low-grade B-cell lymphomas may contribute to the severity of these infections.

VEXAS within the spectrum of rheumatologic disease

The identification of the VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome as a myeloid-driven inflammatory disease resulting from somatic mutations in the UBA1 gene further exposes the increasingly recognized overlap between hematologic disturbances and auto-immunity and/or auto-inflammatory presentations. Although single or multi-lineage cytopenias are a unifying aspect of VEXAS, patients with this condition can present with a wide array of inflammatory findings affecting the skin, lung, joints, eye, vascular system, and cartilaginous structures. As such, it is paramount that generalists, and subspecialty providers familiarize themselves with the clinical characteristics of this condition. This review summarizes the reported clinical symptoms of VEXAS syndrome with a particular focus on its non-hematologic inflammatory features.

Norovirus in Cancer Patients: A Review

Norovirus (NoV) is the leading cause of viral-related diarrhea in cancer patients, in whom it can be chronic, contributing to decreased quality of life, interruption of cancer care, malnutrition, and altered mucosal barrier function. Immunosuppressed cancer patients shed NoV for longer periods of time than immunocompetent hosts, favoring quasispecies development and emergence of novel NoV variants. While nucleic acid amplification tests (NAATs) for NoV diagnosis have revolutionized our understanding of NoV burden of disease, not all NAATs provide information on viral load or infecting genotype. There is currently no effective antiviral or vaccine for chronic NoV infections. Screening for inhibitors of NoV replication in intestinal organoid culture models and creation of NoV-specific adoptive T cells are promising new strategies to develop treatments for chronic NoV in immunosuppressed patients. Herein we summarize data on the epidemiology, clinical manifestations, diagnostic challenges, and treatment of NoV infection in patients with cancer.

Acalabrutinib-related second primary malignancies and nonmelanoma skin cancers in patients with chronic lymphocytic leukaemia (CLL): A systematic review and meta-analysis of randomised controlled trials (RCTs)

Acalabrutinib is a second generation Bruton's tyrosine kinase inhibitor and was recently approved in the treatment of chronic lymphocytic leukaemia. We undertook a systematic review and meta-analysis of randomised controlled trials to determine the risks of acalabrutinib-related second primary malignancies (SPM) and nonmelanoma skin cancers (NMSC). The incidence of SPM was 4.7% higher in the acalabrutinib arm compared to control arm with risk ratio (RR) of 1.76 (5.32 vs 3.2 per 100 person-years). Notably, NMSC was the most common SPM, and the incidence was 2.56 per 100 person-years in the acalabrutinib group versus 1.12 per 100 person-years in the control group (RR 2.43). Long-term follow-up and future studies are necessary to define the actual relationship and their risk factors.

Second cancer incidence in CLL patients receiving BTK inhibitors

Chronic lymphocytic leukemia (CLL) is associated with perturbed immune function and increased risk for second primary malignancies (SPM). Ibrutinib and acalabrutinib (BTKi) are effective therapies for CLL resulting in partial restoration of immune function. The incidence of and risk factors for SPM in CLL patients receiving BTKi are not yet characterized. We retrospectively determined the incidence of SPM in CLL patients treated with ibrutinib or acalabrutinib at our institution between 2009 and 2017, assessed for association between baseline characteristics and SPM incidence, and compared the observed to expected cancer incidence among age, sex, and year matched controls without CLL. After a median of 44 months follow-up, 64/691 patients (9%) were diagnosed with SPM (excluding non-melanoma skin cancer [NMSC]). The three-year cumulative incidence rate was 16% for NMSC and 7% for other SPM. On multivariable analysis, smoking was associated with increased SPM risk (HR 2.8 [95% CI: 1.6–4.8]) and higher baseline CD8 count was associated with lower SPM risk (HR 0.9 for 2-fold increase [95% CI: 0.8–0.9]). The observed over expected rate of SPM was 2.2 [95% CI: 1.7–2.9]. CLL patients treated with BTKi remain at increased risk for SPM, and secondary cancer detection is an important consideration in this population.

Amebic Encephalitis in a Patient with Chronic Lymphocytic Leukemia on Ibrutinib Therapy

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western countries. A common first-line therapy offered to qualifying patients includes ibrutinib, an oral covalent inhibitor of Bruton's tyrosine kinase. Treatment of CLL with ibrutinib therapy is generally well tolerated; however, serious opportunistic infections are being reported in patients treated with ibrutinib. In this report, we present a patient with CLL on ibrutinib therapy who developed rapidly declining neurological status concerning for the central nervous system (CNS) process related to his immunocompromised status. Despite multiple testing modalities, no evidence was found to explain the acute changes the patient was experiencing, and he had no improvement with common antimicrobial coverage. The patient ultimately expired, and autopsy of the brain revealed granulomatous amebic encephalitis due to opportunistic infection by Acanthamoeba species. As evidenced by this case, ibrutinib therapy, despite being generally well tolerated, has the potential to predispose patients to opportunistic infections like amebic encephalitis. Amebic encephalitis is a highly lethal CNS infection, and it is important for clinicians to recognize early on the potential for infection in patients on ibrutinib therapy presenting with CNS symptoms.

Analysis of the risk of infection in patients with chronic lymphocytic leukemia in the era of novel therapies

We studied the risk of infections in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). Major infections were defined as requiring hospital admission or intravenous antimicrobial treatment. Incidence rate (IR) ratios (IRR) were used to compare infection rates. Of 263 CLL patients followed for 936.9 person-years, 60% required treatment for progressive CLL (66 received ibrutinib). Infections occurred in 71.9% patients (IR 92.4/100 person-years) with 31.9% having major infections (IR 20.3/100 person-years) and infections causing 37.5% of deaths. CLL treatment was associated with significantly higher risk of major (IRR 3.31, 95% CI 2.10, 5.21) and minor (IRR 1.78, 95% CI 1.43, 2.22) infections. Compared to their previous chemoimmunotherapy patients receiving salvage ibrutinib therapy (n = 47) had a significantly increased risk of a major infection (IRR 2.35 95% CI 1.27, 4.34). The risk of infection in CLL patients remains high even with use of less immunosuppressive therapies.

Nosocomial Co-Transmission of Avian Influenza A(H7N9) and A(H1N1)pdm09 Viruses between 2 Patients with Hematologic Disorders

Transmission of these viruses was limited to 2 immunocompromised patients in the same ward.

A nosocomial cluster induced by co-infections with avian influenza A(H7N9) and A(H1N1)pdm09 (pH1N1) viruses occurred in 2 patients at a hospital in Zhejiang Province, China, in January 2014. The index case-patient was a 57-year-old man with chronic lymphocytic leukemia who had been occupationally exposed to poultry. He had co-infection with H7N9 and pH1N1 viruses. A 71-year-old man with polycythemia vera who was in the same ward as the index case-patient for 6 days acquired infection with H7N9 and pH1N1 viruses. The incubation period for the second case-patient was estimated to be <4 days. Both case-patients died of multiple organ failure. Virus genetic sequences from the 2 case-patients were identical. Of 103 close contacts, none had acute respiratory symptoms; all were negative for H7N9 virus. Serum samples from both case-patients demonstrated strong proinflammatory cytokine secretion but incompetent protective immune responses. These findings strongly suggest limited nosocomial co-transmission of H7N9 and pH1N1 viruses from 1 immunocompromised patient to another.

Synchronous gastric and ampullary adenocarcinomas in a hairy cell leukemia patient treated with pentostatin eight years prior

Hairy cell leukemia patients are at increased risk for second malignancies, including both solid and lymphoid neoplasms. Along with other factors, multiple immune defects present in hairy cell leukemia likely contribute to subsequent carcinogenesis. We report herein a case of synchronous high-grade gastric and ampullary adenocarcinomas in a patient with a history of hairy cell leukemia treated eight years prior with pentostatin. We include a review of immune alterations induced by both hairy cell leukemia and its therapies, and link them with the occurrence of second cancers in these patients.

Autoimmune manifestations in patients with multiple myeloma and monoclonal gammopathy of undetermined significance

Background

Multiple myeloma (MM) and its precursor, monoclonal gammopathy of undetermined significance (MGUS), have been linked with several autoimmune conditions in the medical literature. Yet, significance of these associations is not well understood.

Methods

Herein, we provide a comprehensive literature review on autoimmune disorders identified in patients with MM and MGUS. Most relevant papers were identified via searching the PubMed/Medline and EMBASE databases for articles published from inception until May 1, 2016.

Findings

Scientific literature on autoimmune conditions in patients with MM and MGUS consists of several case series and a multitude of case reports. Our analysis suggests an increased prevalence of autoimmune conditions in patients with MM and monoclonal gammopathy of undetermined significance (MGUS), including various autoimmune hematologic and rheumatologic conditions among other entities. Conversely, persons with various autoimmune conditions tend to have a higher prevalence of MGUS and MM than the general population.

Conclusions

Future research is required to explore further the link between MGUS/MM and autoimmune disorders. Inflammation in the setting of autoimmunity may serve as a trigger for MGUS and MM. In addition, a common genetic susceptibility for developing both an autoimmune disease and MM/MGUS might also exist. Autoimmune hematologic and rheumatologic diseases may pose important clinical problems for the MM patients. Therefore, a catalogue of these problems is important so that physicians are able to consider, identify and address them promptly.

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A comprehensive review linking MM and MGUS with autoimmune disorders

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There is increased prevalence of autoimmune conditions in patients with MM and MGUS

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Most autoimmune disorders precede the development of plasma cell dyscrasias

Hodgkin's lymphoma as a rare variant of Richter's transformation in chronic lymphocytic leukemia: A case report and review of the literature

Richter's transformation induces an aggressive clinical course in chronic lymphocytic leukemia (CLL). In the majority of cases, Richter's transformation manifests itself as a high-grade B-cell non-Hodgkin's lymphoma (B-NHL). However, other histological types, such as classical Hodgkin lymphoma (cHL), lymphoblastic lymphoma, hairy cell leukemia and high-grade T-cell NHL have been described previously. The present study reports a rare case of CLL with transformation into classical Hodgkin's lymphoma (cHL). The common clonal origin of CLL and cHL was documented by immunoglobulin gene rearrangement analysis performed using multiplex polymerase chain reaction. Following a review of the literature, treatment of secondary Hodgkin's lymphoma is discussed, and prognosis is often poor.

Risk Factors for Melanoma Among Survivors of Non-Hodgkin Lymphoma

PURPOSE

Previous studies have reported that survivors of non-Hodgkin lymphoma (NHL) have an increased risk of developing cutaneous melanoma; however, risks associated with specific treatments and immune-related risk factors have not been quantified.

PATIENTS AND METHODS

We evaluated second melanoma risk among 44,870 1-year survivors of first primary NHL diagnosed at age 66 to 83 years from 1992 to 2009 and included in the Surveillance, Epidemiology, and End Results-Medicare database. Information on NHL treatments, autoimmune diseases, and infections was derived from Medicare claims.

RESULTS

A total of 202 second melanoma cases occurred among survivors of NHL, including 91 after chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and 111 after other NHL subtypes (cumulative incidence by age 85 years: CLL/SLL, 1.37%; other NHL subtypes, 0.78%). Melanoma risk after CLL/SLL was significantly increased among patients who received infused fludarabine-containing chemotherapy with or without rituximab (n=18: hazard ratio [HR], 1.92; 95% CI, 1.09 to 3.40; n=10: HR, 2.92; 95% CI, 1.42 to 6.01, respectively). Significantly elevated risks also were associated with T-cell activating autoimmune diseases diagnosed before CLL/SLL (n=36: HR, 2.27; 95% CI, 1.34 to 3.84) or after CLL/SLL (n=49: HR, 2.92; 95% CI, 1.66 to 5.12). In contrast, among patients with other NHL subtypes, melanoma risk was not associated with specific treatments or with T-cell/B-cell immune conditions. Generally, infections were not associated with melanoma risk, except for urinary tract infections (CLL/SLL), localized scleroderma, pneumonia, and gastrohepatic infections (other NHLs).

CONCLUSION

Our findings suggest immune perturbation may contribute to the development of melanoma after CLL/SLL. Increased vigilance is warranted among survivors of NHL to maximize opportunities for early detection of melanoma.

Investigation of epstein-barr virus as a potential cause of B-cell non-Hodgkin lymphoma in a prospective cohort

BACKGROUND

We hypothesized that poor control of Epstein-Barr virus (EBV) infection, leading to reactivation of the virus, increases the risk of non-Hodgkin lymphoma (NHL) in the general population of primarily immunocompetent persons.

METHODS

We conducted a case-control study nested within the Women's Health Initiative Observational Study cohort in which we measured antibodies to EBV antigens [immunoglobulin G (IgG) to viral capsid antigen (VCA), nuclear antigen (EBNA1), and early antigen-diffuse (EA-D)] and EBV DNA load in prediagnostic samples of 491 B-cell NHL cases and 491 controls.

RESULTS

We found no association with established EBV infection, based on seropositivity for VCA. Seropositivity for EBNA1 was associated with decreased risk of B-cell NHL, overall [OR = 0.5; 95% confidence interval (CI), 0.3-0.8] and for each of the histologic subtypes examined. Increased risk of chronic lymphocytic leukemia (CLL) and related subtypes was observed with higher levels of EBV DNA and antibody to EA-D, both markers reflective of reactivation. These associations were strongest for cases with the shortest time interval between blood draw and diagnosis.

CONCLUSIONS

In balance, these results do not provide strong evidence of EBV playing a causal role in B-cell NHL in general population women. The associations we observed may reflect increased risk of NHL with underlying immune impairment or could be due to reverse causation.

IMPACT

Further characterization of the subtype-specific association with CLL is warranted. Exclusion of cases with preclinical disease markers (such as monoclonal B-lymphocytosis for CLL) may help rule out reverse causation in future studies.

Impaired bactericidal but not fungicidal activity of polymorphonuclear neutrophils in patients with chronic lymphocytic leukemia

We examined the qualitative polymorphonuclear neutrophil (PMN)-associated immune impairment in patients with chronic lymphocytic leukemia (CLL) by characterizing phagocytic killing of key non-opsonized bacterial (Staphylococcus aureus and Pseudomonas aeruginosa) and fungal (Candida albicans and Aspergillus fumigatus) pathogens. Neutrophils were collected from 47 non-neutropenic patients with CLL (PMN count > 1000/mm(3)) and age-matched and young healthy controls (five each). A subset of patients (13%) had prior or subsequent infections. We found that the patients with CLL had diminished PMN microbicidal response against bacteria but not against fungi compared with the controls. Compared to patients with effective PMN responses, we did not identify differences of basal PMN pathogen-associated molecular pattern receptor gene expression, soluble pathogen-associated molecular pattern gene expression or inflammatory cytokine signatures in patients with impaired PMN responses when PMNs were analyzed in multiplex real-time polymerase chain reaction assays. However, differences in PMN microbicidal response against A. fumigatus in patients with CLL were associated with the degree of hypogammaglobulinemia.

Autoimmune manifestations in large granular lymphocyte leukemia

Large granular lymphocyte (LGL) leukemia features a group of indolent lymphoproliferative diseases that display a strong association with various autoimmune conditions. Notwithstanding, these autoimmune conditions have not been comprehensively characterized or systematized to date. As a result, their clinical implications remain largely unknown. The authors offer a comprehensive review of the existing literature on various autoimmune conditions documented in the course of T-cell LGL (T-LGL) leukemia. Though some of them are thought be secondary to the LGL leukemia, others could be primary and might even play a role in its pathogenesis. A considerable clinico-laboratory overlap between T-LGL leukemia associated with rheumatoid arthritis and Felty's syndrome suggests that they are just different eponyms for the same clinical entity.

Two smalls in one: Coincident small cell carcinoma and small lymphocytic lymphoma in a lymph node diagnosed by fine-needle aspiration biopsy

BACKGROUND

B-cell chronic lymphocytic leukemia / small lymphocytic lymphoma (CLL / SLL) is one of the most common lymphoproliferative disorders in western countries. Patients with SLL / CLL are at increased risk of site-specific secondary cancers. We present a unique case of a 71-year-old male, with a history of SLL / CLL, who presented with pulmonary symptoms and a mediastinal mass. Fine needle aspiration (FNA) of the mediastinal lymph node revealed synchronous SLL / CLL and small cell carcinoma (SCC).

MATERIALS AND METHODS

The patient underwent a computed tomography (CT) scan of the chest and endobronchial ultrasound-guided transbronchial fine needle aspiration of the mediastinal lymph node (4R). The sample was submitted for cytopathology, immunohistochemical stains, and flow cytometry evaluation.

RESULTS

Fine needle aspiration of the mediastinal lymph node revealed neoplastic cells, in clusters and singly, with cytological features suggestive of small cell carcinoma. The immunohistochemistry results confirmed this diagnosis. Small-to-medium, mature-appearing lymphocytes were also present in the background. Flow cytometry analysis revealed that these lymphocytes possessed an immunophenotype consistent with CLL / SLL.

CONCLUSIONS

This case illustrates the importance of a pathologist's awareness of the possibility of concurrent lymphoma and metastatic carcinoma in a lymph node. When evaluating lymph nodes, pathologists must strive to identify both foreign cells and subtle lymphoid changes. As demonstrated by our case, ancillary techniques (such as immunohistochemistry and flow cytometry) can be critical to making a complete and accurate diagnosis. The diagnosis of small cell carcinoma in the enlarged lymph node, primarily harboring CLL / SLL, is of critical importance for decision-making and treatment purposes, in addition to having a significant adverse impact on the overall survival.

Autoimmune phenomena in untreated and treated marginal zone lymphoma

INTRODUCTION

Current literature suggests an association between various autoimmune conditions and marginal zone lymphoma (MZL). However, these autoimmune conditions have not been comprehensively systematized to date. As a result, their clinical implications remain largely unknown.

AREAS COVERED

The authors provide a comprehensive review of the existing literature on various autoimmune abnormalities documented in the course of MZL, as well as on autoimmune alterations induced by certain MZL therapies.

EXPERT OPINION

The course of MZL is accompanied by a variety of hematologic and non-hematologic autoimmune disorders. Whereas some of them could be secondary and related to the course of the MZL, others may be primary and might even favor the development of MZL itself. In addition, authentic autoimmune conditions have been documented with the use of rituximab as a single agent and the nucleoside analogs. Therefore, we believe caution should be exerted with the use of these agents in MZL patients with evidence of autoimmune disorders, as exacerbation of autoimmune phenomena can be anticipated. While the heterogeneity of the MZL subtypes represents an inherent limitation, integration of emerging information from immunology research laboratories and clinical practice could translate into improved outcomes of this disease spectrum.

Chronic diarrhea associated with persistent norovirus excretion in patients with chronic lymphocytic leukemia: report of two cases

BACKGROUND

Chronic diarrhea in patients treated with immunosuppressive agents or suffering from immunosuppressive disease can represent a diagnostic and therapeutic challenge to the clinician. Norovirus infection, a major cause of acute epidemic diarrhea, has been described as a cause of chronic diarrhea in patients who are immunosuppressed, including transplant recipients and the very young.

CASE PRESENTATIONS

We describe two patients, a 64 year-old man and a 59 year-old woman, both suffering from chronic lymphocytic leukemia and hypogammaglobulinemia, who developed chronic diarrhea resistant to therapy. In both cases, after months of symptoms, persistent norovirus infection--documented by repeatedly-positive high-sensitivity stool enzyme immunoassay--was found to be the cause. Both patients died with active diarrheal symptoms.

CONCLUSIONS

We describe the first cases of advanced chronic lymphocytic leukemia to suffer from chronic symptomatic norovirus infection. Clinicians caring for such patients, particularly those with concomitant hypogammaglobulinema, who have chronic unexplained diarrhea, should consider norovirus infection in the differential diagnosis.

Second malignancy risks after non-Hodgkin's lymphoma and chronic lymphocytic leukemia: differences by lymphoma subtype

PURPOSE

Previous studies have shown increased risks of second malignancies after non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL); however, no earlier investigation has quantified differences in risk of new malignancy by lymphoma subtype.

PATIENTS AND METHODS

We evaluated second cancer and leukemia risks among 43,145 1-year survivors of CLL/small lymphocytic lymphoma (SLL), diffuse large B-cell lymphoma (DLBCL), or follicular lymphoma (FL) from 11 Surveillance, Epidemiology, and End Results (SEER) population-based registries during 1992 to 2006.

RESULTS

Among patients without HIV/AIDS-related lymphoma, lung cancer risks were significantly elevated after CLL/SLL and FL but not after DLBCL (standardized incidence ratio [SIR], CLL/SLL = 1.42, FL = 1.28, DLBCL = 1.00; Poisson regression P for difference among subtypes, P(Diff) = .001). A similar pattern was observed for risk of cutaneous melanoma (SIR: CLL/SLL = 1.92, FL = 1.60, DLBCL = 1.06; P(Diff) = .004). Acute nonlymphocytic leukemia risks were significantly elevated after FL and DLBCL, particularly among patients receiving initial chemotherapy, but not after CLL/SLL (SIR: CLL/SLL = 1.13, FL = 5.96, DLBCL = 4.96; P(Diff) < .001). Patients with HIV/AIDS-related lymphoma (n = 932) were predominantly diagnosed with DLBCL and had significantly and substantially elevated risks for second anal cancer (SIR = 120.50) and Kaposi's sarcoma (SIR = 138.90).

CONCLUSION

Our findings suggest that differing immunologic alterations, treatments (eg, alkylating agent chemotherapy), genetic susceptibilities, and other risk factors (eg, viral infections, tobacco use) among lymphoma subtypes contribute to the patterns of second malignancy risk. Elucidating these patterns may provide etiologic clues to lymphoma as well as to the second malignancies.

Risk of additional cancers in untreated and treated hairy cell leukemia patients

IMPORTANCE OF THE FIELD

One of the feared events encountered in hairy cell leukemia (HCL) survivors is the subsequent development of a malignant neoplasm. The increased incidence of second cancers in HCL has been documented in large epidemiologic studies conducted in various locations on the globe.

AREAS COVERED IN THIS REVIEW

The authors explore the current clinico-epidemiologic evidence, as well as the immune alterations, that link HCL and its therapies to the development of second cancers. Most relevant publications have been identified through the PubMed/Medline database search.

WHAT THE READER WILL GAIN

Although HCL patients could develop both HCL and secondary malignancies because of a shared genetic predisposition, a common environmental carcinogen, or not yet identified infectious agents, multiple immune defects documented in HCL might play an important role in second carcinogenesis. Furthermore, the 'gold standards' of HCL therapy - cladribine and pentostatin - are associated with profound and prolonged suppression of the CD4(+) T-lymphocyte counts, often in excess of 2 - 3 years. And while there is no clear-cut evidence that pentostatin or interferon-alpha play an established role in generation of an excess of second cancers in HCL, the safety of cladribine, the preferred agent by a majority of clinicians worldwide, in this regard is a still largely unsettled issue.

TAKE-HOME MESSAGE

Therefore, it remains to be seen if the immune deficiencies induced by the HCL therapies and their consequences can be offset by the benefit conferred by controlling the leukemic process.