Primary central nervous system lymphoma in acquired immune deficiency syndrome. A clinical and pathologic study with results of treatment with radiation

GESIDA/PETHEMA recommendations on the diagnosis and treatment of lymphomas in patients infected by the human immunodeficiency virus

The incidence of non-Hodgkin's lymphoma and Hodgkin's lymphoma is higher in patients with HIV infection than in the general population. Following the introduction of combination antiretroviral therapy (cART), the prognostic significance of HIV-related variables has decreased, and lymphoma-related factors have become more pronounced. Currently, treatments for lymphomas in HIV-infected patients do not differ from those used in the general population. However, differentiating characteristics of seropositive patients, such as the need for cART and specific prophylaxis and treatment of certain opportunistic infections, should be considered. This document updates recommendations on the diagnosis and treatment of lymphomas in HIV infected patients published by GESIDA/PETHEMA in 2008.

Impact of therapeutic regimen and clinical presentation on overall survival in CNS lymphoma

BACKGROUND

The authors present a retrospective analysis of 45 patients who underwent treatment of CNS lymphoma (both primary and secondary) at a single institution between 2005 and 2012.

METHODS

This study involves 21 female and 24 male patients with a mean age of 59.2 years. All medical records and pathology reports were reviewed for each patient. Univariate and multivariate analyses of overall survival were performed.

RESULTS

Presentation with altered mental status was a significant risk factor for worse overall survival. An HIV infection, deep lesion location, and age over 60 did not impact survival. A survival benefit was demonstrated with the use of systemic therapy, specifically rituximab, and radiation. The CNS Lymphoma Score was derived from this cohort, which proved a powerful predictive tool for overall survival. The surgical complication rate in this series was 17.8 %.

CONCLUSIONS

This study highlights the prognostic importance of presenting mental status on outcomes in CNS lymphoma and demonstrates a summative benefit of rituximab and whole brain radiation therapy. Considering these factors together provides an easily applicable and meaningful stratification for this patient population. The surgical complication rate in this patient population is not negligible. The high percentage of wound-related surgical complications suggests the need for a waiting period between surgery and initiation of chemotherapy to allow for wound healing.

Radiation therapy for HIV-associated diffuse large cell non-Hodgkin lymphoma

PURPOSE

To report the clinical experience with external beam radiotherapy (RT) for AIDS-related lymphoma (ARL) with or without the involvement of the central nervous system (CNS) in HIV-infected patients.

PATIENTS AND METHODS

Clinical outcome of 24 HIV-seropositive patients with ARL treated with RT from 1995 to 2004 was reviewed, testing factors associated with outcome.

RESULTS

After 1 and 5 years, the overall survival was 65% and 35%, respectively. The mean RT dose was 31 Gy after normalization to fractions of daily 2 Gy (range, 7.8-47.2 Gy). Radiotherapy dose was associated with survival in univariate (P = .04) and multivariate analysis (P = .01). Other factors in univariate analysis associated with outcome were viral load (VL), highly active antiretroviral therapy (HAART), ARL stage, and CNS involvement. Patients with CNS involvement achieved complete response in 46% and improved clinical performance was seen in 73%.

CONCLUSIONS

After chemotherapy, RT in combination with HAART is highly active, and RT should be encouraged especially after suboptimal responses to induction treatment.

AIDS malignancies

Among individuals with HIV-infection, coinfection with oncogenic viruses including EBV, HHV-8, and HPV cause significant cancer-related morbidity and mortality. It is clear that these viruses interact with HIV in unique ways that predispose HIV-infected individuals to malignant diseases. In general, treatment directed specifically against these viruses does not appear to change the natural history of the malignant disease, and once the malignancy develops, if their health permits, HIV-infected patients should be treated using similar treatment protocols to HIV-negative patients. However, for the less frequent HIV-related malignancies, such as PEL, or MCD, optimal treatments are still emerging. For certain AIDS-defining malignancies, it is clear that the widespread access to HAART has significantly decreased the incidence, and improved outcomes. However, for other cancers, such as the HPV-related tumors, the role of HAART is much less clear. Further research into prevention and treatment of these oncogenic virally mediated AIDS-related malignancies is necessary.

Highly Active Antiretroviral Therapy and Human Immunodeficiency Virus–Associated Primary Cerebral Lymphoma

From a cohort of 9621 human immunodeficiency virus type 1-infected individuals, we identified 61 patients with primary central nervous system lymphoma (PCL) who had a median survival of 1.3 months. We compared clinicopathologic variables of patients who were treated in the pre-highly active antiretroviral therapy (HAART) and HAART eras and investigated whether exposure to antiretroviral agents with differing cerebrospinal fluid penetrations was associated with risk for PCL. All statistical tests were two-sided. Incidence of PCL was lower in the HAART era (1.2 cases per 1000 patient-years, 95% confidence interval [CI] = 0.8 to 1.9) than in the pre-HAART era (three cases per 1000 years, 95% CI = 2.1 to 4.0; P<.001), and overall survival was longer (median survival = 32 days, range = 5-315 days, versus 48 days, range = 15-1136 days; log rank P = .03). In the HAART era, fewer patients had prior acquired immunodeficiency syndrome-defining illnesses than in the pre-HAART era (64% versus 90%; P = .013), and patients were more likely to have the diagnosis of PCL confirmed histologically or by polymerase chain reaction (77% versus 26%; P<.001). Exposure to specific antiretroviral agents was not associated with risk for PCL.

Leptomeningeal metastases from leukemias and lymphomas

Leptomeningeal dissemination of lymphoma and leukemia differs from that of solid tumors in a number of clinically important aspects. Specific histologic variants of lymphoma and leukemia have such a high incidence of cerebrospinal fluid (CSF) dissemination that assessing CSF cytology at diagnosis is crucial and prophylactic therapy of the CSF compartment is required. Furthermore, while the overall prognosis for patients with leptomeningeal metastases from leukemia and lymphoma is similar to solid tumors, selected patients have excellent response to therapy and attain durable remission. Therefore, aggressive treatment is warranted.

AIDS-Related Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) can develop in the setting of profound immunosuppression, including late-stage infection with HIV. The management of such patients has yet to be defined optimally and differs substantially from that of immunocompetent patients who have PCNSL. The clinical features, diagnosis, and management of AIDS-related PCNSL are reviewed. The authors focus on commonly encountered diagnostic and therapeutic dilemmas and explore some promises and pitfalls of Epstein-Barr virus-directed therapies.

Guidelines for the diagnosis and management of neurological complications of HIV infection

The spectrum of neurological complications of HIV-infection has remained unchanged through the years, but its epidemiology changed remarkably as a result of the introduction of highly active antiretroviral therapy (HAART). Guidelines for the diagnosis and treatment of cerebral toxoplasmosis, cryptococcal meningitis, progressive multifocal leukoencephalopathy, CMV encephalitis, CMV polyradiculomyelitis, tuberculous meningitis, primary CNS lymphoma, HIV dementia, HIV myelopathy and HIV polyneuropathy are given with a grading of evidence and recommendations.

Human immunodeficiency virus-related primary central nervous system lymphoma

BACKGROUND

The current study evaluated factors influencing survival in patients diagnosed with human immunodeficiency virus (HIV)-related primary central nervous system lymphoma (PCNSL), with a focus on the effects of therapeutic radiotherapy (RT) and highly active antiretroviral therapy (HAART).

METHODS

A retrospective chart review of patients with a diagnosis of HIV-related PCNSL at one of five university hospitals between 1987 and 1998 was performed. Clinical details including antiretroviral agent use, brain imaging scan results, RT use, and survival outcomes were recorded.

RESULTS

One hundred eleven patients with HIV-related PCNSL were identified. The annual incidence decreased significantly between 1992 and 1995 and between 1996 and 1998 (P = 0.04). The median survival period was 50 days (mean, 109 days; range, 4-991 days), with improved survival for patients diagnosed after 1993. Patients treated with two or more antiretroviral agents had improved survival (P = 0.01), as did patients who received RT (P < 0.0001). For patients who received RT, completion of the prescribed course and treatment to > or = 30 Gray (Gy) independently predicted a more favorable outcome. RT used in conjunction with antiretroviral therapy involving two or more agents had an additive positive effect on survival. For patients who did not receive RT, poor performance status and encephalopathy predicted a shorter survival duration.

CONCLUSIONS

The results of the current study suggest that HAART and treatment with RT to > or = 30 Gy improve survival for patients with HIV-related PCNSL. This combination of therapies may provide a standard of care as the basis for further trials of chemotherapy, novel adjunctive treatment, and quality of life assessment.

Survival is prolonged by highly active antiretroviral therapy in AIDS patients with primary central nervous system lymphoma

OBJECTIVE

To determine the effects of highly active antiretroviral therapy (HAART) on survival in AIDS-related primary central nervous system lymphoma (PCNSL).

METHODS

Survival in consecutive patients with PCNSL at a large county teaching hospital from 1995 to 2001 were analyzed by the log rank test and Cox proportional hazards ratios (HR) were calculated for factors potentially affecting survival.

RESULTS

During the study period, 25 patients were diagnosed with PCNSL: 19 definite and 6 probable. At diagnosis, median CD4 cell count was 12 x 10(6) cells/l (range 1-151) and median HIV viral load was 5.3 log(10) copies/ml (range 3.9-5.9). Sixteen patients died (median survival 87 days; range, 0 to > 2112). Longer survival was noted for patients who received HAART after diagnosis [HR for death, 0.06; 95% confidence interval (CI), 0.01-0.48]. Six of seven HAART-treated patients were alive versus 0/18 untreated patients at a median follow-up time of 667 days (P = 0.0007 by log rank test). A survival benefit was seen for patients who had >/= 0.5 log(10) copies/ml decrease in HIV viral load after diagnosis (n = 6; HR, 0.07; 95% CI, 0.01-0.55) and for patients with a significant CD4 cell rebound (increase >/= 50 x 106 cells/l) in response to HAART (n = 6): all survived versus 0/19 survived (P = 0.0003). Cranial radiation therapy (n = 13) prolonged survival (HR, 0.20; 95% CI, 0.07-0.58). Median survival was only 29 days for 11 patients who received neither radiation nor HAART.

CONCLUSIONS

Receipt of HAART after diagnosis is associated with a significantly longer survival in patients with AIDS-related CNS lymphoma.

Etiology and pathogenesis of AIDS-related non-Hodgkin's lymphoma

The incidence of NHL is greatly increased in HIV-infected individuals; malignant lymphoma is the second most common neoplasm that occurs in association with AIDS. The vast majority of neoplasms are clinically aggressive, monoclonal B-cell neoplasms that exhibit Burkitt's, immunoblastic, large cell, or transitional histopathology. Approximately 80% arise systemically (nodal or extranodal) and 20% arise as primary CNS lymphomas. A small proportion of neoplasms are body cavity-based, primary effusion lymphomas that are uniquely associated with KSHV infection. Recently, HIV-associated polymorphic lymphoproliferative disorders have been described as well. AIDS-related NHLs appear to exhibit distinctive clinical characteristics according to their histopathology and anatomic site of origin. Factors that contribute to lymphoma development include HIV-induced immunosuppression, impaired immune surveillance, cytokine release and deregulation, and chronic antigenic stimulation. This environment is associated with the development of oligoclonal B-cell expansions. The appearance of NHL is characterized by the presence of a monoclonal B-cell population that displays a variety of genetic lesions, including, for example, EBV infection, MYC gene rearrangement, BCL6 gene rearrangement, P53 mutations and deletions, and RAS gene mutations. The number and type of genetic lesions vary somewhat among AIDS-related NHLs according to their histopathologic category and anatomic site of origin. These findings suggest that more than one pathogenetic mechanism is operational in the development and progression of AIDS-related NHLs. Further work is necessary to develop a complete understanding of the etiology and pathogenesis of NHL in the setting of HIV infection. AIDS-related NHL is an important biologic model for investigating the development and progression of high-grade NHLs and NHLs that develop in immunedeficient hosts.

Biology and management of AIDS-associated non-Hodgkin's lymphoma

The treatment of HIV-related lymphomas is evolving in the era of HAART. Standard-dose chemotherapy and dose-intensive therapies appear to be feasible. Whether outcomes are improved with combination chemotherapy and HAART remains unclear. Efforts aimed at developing pathogenic-based therapies will continue as the mechanisms of HIV lymphomagenesis are elucidated.

Focal neurological disease in patients with acquired immunodeficiency syndrome

Focal neurological disease in patients with acquired immunodeficiency syndrome may be caused by various opportunistic pathogens and malignancies, including Toxoplasma gondii, progressive multifocal leukoencephalopathy (PML), cytomegalovirus (CMV), and Epstein-Barr virus-related primary central nervous system (CNS) lymphoma. Diagnosis may be difficult, because the findings of lumbar puncture, computed tomography (CT), and magnetic resonance imaging are relatively nonspecific. Newer techniques have led to improved diagnostic accuracy of these conditions. Polymerase chain reaction (PCR) of cerebrospinal fluid specimens is useful for diagnosis of PML, CNS lymphoma, and CMV encephalitis. Recent studies have indicated the diagnostic utility of new neuroimaging techniques, such as single-photon emission CT and positron emission tomography. The combination of PCR and neuroimaging techniques may obviate the need for brain biopsy in selected cases. However, stereotactic brain biopsy, which is associated with relatively low morbidity rates, remains the reference standard for diagnosis. Highly active antiretroviral therapy has improved the prognosis of several focal CNS processes, most notably toxoplasmosis, PML, and CMV encephalitis.

Survival of AIDS patients with primary central nervous system lymphoma is dramatically improved by HAART-induced immune recovery

OBJECTIVE

To evaluate the impact of immune recovery induced by highly active antiretroviral therapy (HAART) on the survival of AIDS patients with primary central nervous system lymphoma (PCNSL).

METHODS

In a multicentric retrospective analysis, 29 HIV-infected patients with histologically confirmed PCNSL were identified. To evaluate median survival, Kaplan-Meier statistics were used. To explore the effects of different variables on survival, a Weibull accelerated failure time regression analysis was performed.

RESULTS

Median age at manifestation of PCNSL was 39.1 years and median CD4 cell count was 11 x 10(6) cells/l. Seventy per cent of the patients had had a prior AIDS-defining illness. Cranial radiation (CR) was given to 12 out of 29 patients. Six patients were treated with HAART. Survival time of these patients and of the patients treated with CR alone differed significantly from those receiving neither CR nor HAART (median Kaplan-Meier survival estimate: 1093, 132, and 33 days, respectively). In the multivariate regression model, HAART and CR were identified as the only variables independently associated with prolonged survival. HAART versus no HAART and CR versus no CR increased the time to event by a factor of 6.1 (95% confidence interval, 2.4-16.0; P = 0.0002) and 3.1 (95% confidence interval, 1.5-6.3; P = 0.002), respectively. Four out of six patients on HAART showed a marked immune recovery and survived for more than 1.5 years, with two patients still alive.

CONCLUSION

Data from this cohort indicate that immune recovery induced by HAART leads to dramatic improvement in survival of patients with AIDS-associated PCNSL. These findings may have important implications for future treatment strategies.

Clinical aspects and management of AIDS-related lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) is increased by approximately 100-fold in patients with advanced HIV infection. Clinical presentations may include systemic lymphoma, primary central nervous system (CNS) lymphoma, and primary effusion lymphoma. Systemic lymphoma is the most common presentation, is almost always of intermediate or high-grade histology and B-cell phenotype, and usually involves extranodal sites. The disease is potentially curable with combination chemotherapy used for immunocompetent patients with lymphoma, although cure is achieved in only approximately 10-35% of patients. Primary CNS lymphoma may be difficult to distinguish from cerebral infection. The prognosis is very poor, although approximately 10% of patients selected for therapy may survive beyond 1 year with brain irradiation. Attention to infection prophylaxis and antiretroviral therapy is important. Evidence suggests that highly active antiretroviral therapy (HAART) has resulted in a decreased incidence of lymphoma, and that patients with systemic lymphoma treated in the post-HAART era have a better prognosis.

Acquired immunodeficiency syndrome-related primary cerebral lymphoma: response to irradiation

Acquired immunodeficiency syndrome-related primary cerebral lymphoma (AIDS-PCL) is uncommon. Fourteen cases of presumed AIDS-PCL between 1986 and 1995 were reviewed retrospectively in order to characterize the natural history, and the response to radiotherapy. The median age was 38 years (range 24-65). The median interval between seropositive diagnosis of HIV and AIDS-PCL was 28 months (range 5-113). The median duration of symptoms was 2 weeks (range 0.2-12). At presentation, the Eastern Cooperative Oncology Group performance status (PS) was PS1 (2/14 patients), PS2 (6/14) and PS3 (6/14). The symptoms and signs were non-specific and depended on the site and extent of cerebral involvement. There was no characteristic pattern of brain imaging in terms of size, number, location or pattern of contrast enhancement of the cerebral lesions. Nine patients received various fractionation-dose schedules (range 8-50 Gy). Complete and partial responses were seen in 2/9 and 3/9 cases, respectively. Clinical stabilization of neurological symptoms was noted in 3/9 cases and disease progression in 1/9. The median survival times (MST) from presentation for irradiated and non-irradiated patients were 9.3 and 2.1 weeks, respectively (range 0.9-43.1). Although patient selection introduced bias, there appears to be a modest improvement in MST for treated patients. The MST with radiotherapy alone remains poor, but radiotherapy may provide palliation. For some selected patients, a prolonged response is possible.

Immunotherapy of a murine T cell lymphoma localized to the brain

Mouse YC8 T cell lymphoma was used as a model to determine whether an effective immunotherapy procedure could be devised for the treatment of lymphoma localized to the brain. Implantation of 5 x 10(4) YC8 cells into the left cerebral hemisphere induced rapid loss of the animal's body weight. Severe loss of weight and early deaths were observed in the untreated control group. Although resistance can be conferred to the brain by immunization of naive BALB/c mice, adoptive chemoimmunotherapy procedures were surprisingly not effective in inducing remissions in animals with lymphoma confined to the brain. Even passive transfer of effector cells from immunized, tumor resistant donor animals combined with systemic IL-2 treatment did not impart resistance to recipients with brain tumors. However, regression of the intracranial tumor and apparent cures could be accomplished, when ex vivo cultured effector cells were transferred intravenously.

Stereotactic biopsy of cerebral lesions in AIDS

Stereotactic brain biopsy was used to establish diagnoses of conditions in patients with AIDS. Two hundred fifty stereotactic biopsies and one open resection were performed for 243 patients. Pathologically abnormal tissue was obtained in 246 (98%) of the procedures, and 16 patients (6%) had >1 diagnosis. Diagnoses included lymphoma in 82 (33%), progressive multifocal leukoencephalopathy in 73 (30%), and tumors not ordinarily associated with AIDS in 7 (3%). In one-third of the cases, the tissue diagnosis differed from the predicted diagnosis. Four of the first 32 patients (12%) developed intracranial bleeding hours after surgery, which was fatal in 3 (9%). Subsequently, all patients were treated with a coagulopathy protocol that included preoperative and postoperative administration of coagulation factors, and there were no further instances of delayed bleeding in the 218 subsequent patients. Among those later patients, there were 7 complications (3%), leading to 4 deaths (2%), a complication rate that compares favorably with that among patients without AIDS.

Head and neck manifestations of non-Hodgkin's lymphoma in human immunodeficiency virus-infected patients

PURPOSE

Non-Hodgkin's lymphoma is the 2nd most common malignancy in human immunodeficiency virus (HIV)-infected patients. However, limited information regarding head and neck manifestations of non-Hodgkin's lymphoma is present in the literature. The aim of this article is to describe the head and neck manifestations of non-Hodgkin's lymphoma in HIV-infected patients and compare it with that seen in noninfected patients.

PATIENTS AND METHODS

A case-control study was performed including 124 patients with non-Hodgkin's lymphoma presenting over a 5.5-year period to tertiary care center in a metropolitan location.

RESULTS

Overall, the anatomic distribution of non-Hodgkin's lymphoma is not altered in the presence of HIV infection with the head and neck region (63%) most often involved overall. However, within the head and neck region, extralymphatic disease is significantly more common in HIV-infected patients (59%) than noninfected patients (33%; P = .001). Central nervous system (CNS) involvement accounts for 41% of head and neck non-Hodgkin's lymphoma in HIV-infected patients, in contrast to only 12% of noninfected patients. High-grade lymphoma (68%) are more common than intermediate (30%) or low-grade disease (2%) in the HIV-infected population, whereas low (24%) and intermediate (60%) grades are more common than high-grade lymphoma (16%) in noninfected patients (P < .001). The large cell immunoblastic type (48%) is the most common subtype in HIV-infected patients, whereas diffuse large-cell type (32%) was most common in HIV-negative patients (P < .05). Survival is significantly poor for HIV-infected patients (P < .05). The impact of HIV infection on survival remain significant even after controlling for the effects of confounding factors.

CONCLUSIONS

Head and neck involvement with non-Hodgkin's lymphoma occurs in a significant number of HIV-infected patients. Our data show that the distribution and course of non-Hodgkin's lymphoma is unique in HIV-infected patients. A high level of suspicion for non-Hodgkin's lymphoma is required in all cases of head and neck lesions in patients with HIV infection to facilitate management.

Primary central nervous system lymphoma: from clinical presentation to diagnosis

Immunocompetent patients with primary central nervous system lymphoma (PCNSL) present with a median age of 55 years, immunosuppressed patients with a median age of 40 years. They show a broad range of signs and symptoms. Symptoms of increased intracranial pressure and personality change are most frequent, followed in frequency by ataxia and hemiparesis. The median time from onset of symptoms to diagnosis is 3-5 months in immunocompetent patients and 2 months in immunodeficient patients. The time to diagnosis can be considerably longer in patients with slowly developing personality change or fluctuating symptoms due to spontaneous or steroid-induced remission of so-called sentinel lesions. Native CT scans show iso- or hyperdense lesions with homogenous contrast enhancement. T1-weighted MRI scans show hypointense and T2-weighted scans hyperintense lesions. The definitive diagnosis of PCNSL requires biopsy. In some cases, however, the definitive diagnosis may exclusively be made by the demonstration of malignant B-lymphocytes in the cerebrospinal fluid.

AIDS-related central nervous system lymphomas

PURPOSE

To evaluate combined radio-chemotherapy in patients with AIDS-related lymphomatous meningitis (LM) or primary central nervous system lymphoma (PCNSL).

PATIENTS AND METHODS

Eighteen men and 2 women with AIDS had cytologically documented LM. Fifteen patients had systemic non-Hodgkin's lymphoma with LM and 5 patients had PCNSL with CSF dissemination. Standardized pre-treatment evaluations included contrast cranial MRI, placement of an intraventricular reservoir, contrast spine MRI, ophthalmologic evaluation and 111Indium-DTPA CSF flow studies. Regions of bulky or symptomatic disease were treated with limited-field irradiation. Concurrent systemic chemotherapy was administered in 18 patients. All patients were scheduled to receive intraventricular methotrexate (MTX) according to a concentration x time (C x T) drug schedule. In cytologic or clinical failures, patients were treated with salvage therapy using intraventricular ara-C and in a similar manner, patients were treated with intraventricular thio-TEPA following cytologic relapse or clinical failure intraventricular following intraventricular ara-C. Sixty-seven patients (63 men; 4 women) with PCNSL underwent a standardized pre-treatment evaluation as in patients with LM and were treated according to 3 schedules. In the first group (n = 15), comfort care was offered. In the second group (n = 45), whole brain radiotherapy was administered. In the third group (n = 7), patients were treated with combined radio- and chemotherapy using systemic procarbazine, CCNU and vincristine (PCV-3). The third group was selected based on a Karnofsky performance status > or =60, no evidence of disseminated PCNSL, a CD4 count >200, no concurrent opportunistic infection and a patient's desire for aggressive therapy.

RESULTS

In the LM patient group, 16 patients were evaluable as 4 patients subsequently withdrew consent for treatment. Median time to tumor progression/survival were as follows: not-treated (n = 4) 12 days/ month; treated non-responding (n = 6) 30 days/2 months; and treated responding (n = 10) 130 days/6 months. In the PCNSL patient group, median range survival were as follows: comfort care (n = 15) 1.5/0.5-3 months; whole brain radiotherapy (n = 45) 4/1.5-5 months; and combined radio-chemotherapy (n = 7) 13/10-18 months.

CONCLUSIONS

Combined radio- and chemotherapy is appropriate for a small subset of patients with AIDS and either LM or PCNSL. This approach results in meaningful palliation not strikingly dissimilar from that seen in non-AIDS patients.

A new xenograft model of primary central nervous system lymphoma

The management of primary lymphoma of the central nervous system (PCNSL) remains controversial and patients' outcome dismal. In order to investigate new selective therapeutic strategies in a controlled system, a reproducible model of PCNSL in nude rats was developed and characterized. Human B lymphoma cells (BL2) were implanted in the brain frontal area in New Zealand nude rats through a silastic device sealed to the skull. Fifteen and 30 days post-implantation, animals were sacrificed. An autopsy was performed. Representative brain sections were cut and examined for the presence of lymphoma. Immunohistochemistry was performed for proliferation (MIB1-Ki67), a B-cell marker (L26-CD20), a T-cell marker (UCHL1-CD45RO). The analysis of the brains showed tumor growth in 88% of the rats. No mortality was observed. At autopsy no extracerebral, spinal or cerebellar metastasis were found. Microscopically the brain tumors appeared non-encapsulated, highly vascularized, with a characteristic perivascular and diffuse lymphomatous spread in the parenchyma. Immunohistochemistry showed a marked positivity of the tumor cells for L26. Tumor cells were negative for UCHL1. Mean proliferation rate was 30%. The device was well tolerated and caused no local infection. Controlled studies on PCNSL in animal models are lacking. This PCNSL model in nude rats reproduces the histology and location of human CNS lymphoma. Tumor dimensions are within the resolution limits of CT and MRI and therefore suitable for stereotactic therapy. This model provides a tool to test new chemo and radiotherapeutical strategies in a controlled fashion.

Treatment outcome in presumed and confirmed AIDS-related primary cerebral lymphoma

A retrospective analysis identified 38 HIV seropositive patients with a diagnosis of presumed (n = 26) or confirmed (n = 12) primary cerebral lymphoma (PCNSL). All patients had failed to respond to empirical antitoxoplasma therapy and the clinical diagnosis of PCNSL was confirmed by brain biopsy (n = 4), cerebrospinal fluid (CSF) examination for Epstein-Barr virus (EBV) by PCR (n = 7) or postmortem examination (n = 1). There was no difference in the age, performance status, CD4 counts, antiretroviral usage or interval since first HIV serodiagnosis between patients with presumed or confirmed PCNSL. 16 patients received either radiotherapy (n = 14) or chemotherapy (n = 2). Patients with confirmed or presumptive PCNSL were equally likely to receive treatment. The median overall survival, which was measured from the end of unsuccessful antitoxoplasma therapy, was 1.2 months for the whole cohort. There was no difference in overall survival between patients with presumptive (median 0.8 months) and confirmed (median 1.3 months) PCNSL (logrank P = 0.69). This suggests that there may be little value in positively diagnosing PCNSL in the current diagnostic algorithm. Recent improvements in outcome have been reported with systemic chemotherapy in HIV-PCNSL and may influence the need for earlier definitive diagnosis in the future.

AIDS-associated malignancies: research perspectives

The appearance in 1981 of a usually rare malignancy, Kaposi's sarcoma, in homosexual men [1] was one of the first harbingers of an epidemic caused by a retrovirus, human immunodeficiency virus (HIV), which causes the acquired immunodeficiency syndrome (AIDS). Lymphoid and other malignancies were also increased, most strikingly non-Hodgkin's lymphoma and primary central nervous system (CNS) lymphoma. Advances in molecular biology, immunology, virology, and anti-viral therapy have combined to create unique research opportunities. One developing theme is the role of viral co-infection and malignancy. Human herpes virus 8 (HHV8), Epstein-Barr virus (EBV) and papilloma virus each may have a causal role in the development of HIV-associated malignancy. New antiretroviral therapies are able to substantially reverse or delay the profound immunosuppression of HIV infection. The changes in the epidemiology of malignancies, and understanding the mechanism of action of these new therapeutics provide research opportunities to understand the pathogenesis of these malignancies. The opportunities to discover the consequences of T-cell based immunodeficiency and the interactions with specific viral pathogens will likely lead to progress in HIV treatment and new strategies for other malignancies.

Minimally invasive diagnosis of acquired immunodeficiency syndrome-related primary central nervous system lymphoma

BACKGROUND

The detection of Epstein-Barr virus (EBV)-DNA in cerebrospinal fluid (CSF) by means of the polymerase chain reaction (PCR) has been revealed, in retrospective studies, to be a good marker of primary central nervous system lymphoma (PCNSL) related to acquired immunodeficiency syndrome (AIDS); however, the technique's usefulness in the management of AIDS patients with focal brain lesions is still unknown. We studied the clinical usefulness of testing CSF obtained by lumbar puncture for the presence of EBV-DNA as a minimally invasive approach to the diagnosis of AIDS-PCNSL in patients with focal brain lesions.

METHODS

Human immunodeficiency virus (HIV)-infected patients with focal brain lesions, observed prospectively during a 30-month period, underwent lumbar puncture if not contraindicated; otherwise, ventricular CSF was obtained at brain biopsy. The presence of EBV-DNA was determined by means of PCR.

RESULTS

We evaluated 122 patients: 42 diagnosed with brain lymphoma and the remaining 80 diagnosed with other brain disorders. Cerebrospinal fluid was collected from 101 patients--by lumbar puncture in 95, including 40 patients with AIDS-PCNSL. The sensitivity and specificity of PCR for EBV-DNA detection in lumbar CSF were 80% (95% confidence interval [CI] = 60.9%-91.6%) and 100% (95% CI = 92.6%-100%), respectively. Lumbar puncture and subsequent assessment of EBV-DNA would have allowed a correct diagnosis in 63.2% (95% CI = 46.0%-77.7%) of patients with AIDS-PCNSL and excluded this diagnosis in 76.3% (95% CI = 65.2%-84.8%) of patients without lymphoma (because EBV-DNA was not detected).

CONCLUSIONS

The presence of EBV-DNA in lumbar CSF is a sensitive and highly specific diagnostic marker of AIDS-PCNSL, and EBV-DNA detection in this fluid may allow a minimally invasive diagnosis in a large percentage of patients with brain lymphomas.

Toxoplasma encephalitis in a HIV patient: unusual involvement of the corpus callosum

In patients with acquired immuno-deficiency syndrome, the differential diagnosis between primary brain lymphoma and toxoplasma encephalitis is not radiologically always straightforward, especially in the presence of a solitary cerebral lesion. In this context, involvement of the corpus callosum is almost exclusively associated with primary brain lymphoma. We describe here an HIV-infected patient who presented with a single and large cerebral lesion affecting the corpus callosum, suggestive of primary brain lymphoma on MRI-scan but who nonetheless responded clinically and radiologically to an anti-toxoplasma drug trial confirming the diagnosis of toxoplasma encephalitis.

Intravenous methotrexate for primary central nervous system non-Hodgkin's lymphoma in AIDS

OBJECTIVE

To evaluate high-dose intravenous methotrexate in primary central nervous system (CNS) lymphoma in HIV-infected patients.

DESIGN

An uncontrolled pilot trial.

SETTING

An infectious diseases department in Paris, France.

PATIENTS

All consecutive AIDS patients with primary CNS lymphoma attending the same unit from August 1994 to March 1996.

INTERVENTIONS

Methotrexate was intravenously administered at a dose of 3 g/m2 every 14 days with leucovorin rescue. A maximum of six cycles was planned. Steroids were given to all patients and haematological growth factors were administered as required.

MAIN OUTCOME MEASURES

Rate of response, time to response and survival.

RESULTS

Fifteen patients (10 with histological documentation) were recruited. The median time since clinical onset was 27 days (range, 7-69 days), median Karnofsky score was 51 (range, 30-70), and mean CD4+ cell count was 30 +/- 19 x 10(6)/l (range, 7-69 x 10(6)/l). Complete responses, defined as clinical improvement and disappearance of contrast-enhancing brain abnormalities on computed tomography or magnetic resonance imaging, were obtained in seven out of 15 patients (three out of 10 patients with histological diagnosis and four out of five patients without histological confirmation). The Karnofsky score of these seven patients improved to 80 +/- 10 (range, 70-100). The mean time taken to respond was 62 +/- 20 days (range, 45-90 days). One patient relapsed at 6 months. Six patients failed to respond, and two died of severe sepsis on days 15 and 45. The median survival time was 290 days (range, 11-570 days): 73 days (range, 11-570 days) in the 10 patients with histological diagnosis, and 347 days (range, 286-409 days) in the five patients without histological confirmation. Side-effects occurred in 10 patients, with gastrointestinal disorders in five, mucositis and skin rash in two, and fever in three patients; however, these events were mild and did not require cycle postponement or dose changes. No cognitive dysfunction occurred.

CONCLUSION

Methotrexate appears to be an attractive alternative to radiation therapy for primary CNS lymphoma and is associated with a far greater improvement in quality of life relative to historical series of radiation therapy.

Computerized tomography and magnetic resonance guided stereotactic brain biopsy in nonimmunocompromised and AIDS patients

BACKGROUND

The utility of stereotactic brain biopsy (SBB) in AIDS patients still remains controversial. The authors investigated SBB-related diagnostic accuracy, complications, and postoperative sequelae in nonimmunocompromised (NIC) patients and AIDS patients. The role of bioptic yield in treatment planning was also studied in AIDS patients.

METHODS

From 1990-95, 200 computerized tomography (CT) or magnetic resonance imaging (MRI)-guided SBBs were performed in our Department; 172 bioptic procedures were performed in NIC patients (169), and 28 SBBs in AIDS patients (27). The statistical significance was evaluated using the Fisher exact t-test.

RESULTS

SBB accuracy was very high in both NIC (94.8%) and AIDS (92.9%) patients. Statistical analysis indicated nonsignificant (NS) differences between the two study groups (P > 0.05). Diagnostic yield resulted higher in contrast-enhancing (CE) brain lesions (98.6% in NIC and 95.0% in AIDS patients; P > 0.05; NS), than in non-CE lesions (74.1% in NIC and 87.5% in AIDS patients; P > 0.05; NS). The overall complication rate was similar in both groups (17.2% in NIC and 14.8% in AIDS patients, P > 0.05, NS). The most frequent complication was hemorrhage, with statistically negligible differences between the two study groups (P > 0.05). The frequency of complications involving minor/major morbidity or mortality was very low in NIC (5.9%, 0.6%, and 2.4%, respectively), and in AIDS (3.7%, 7.4%, and 0.0%, respectively) patients. Regarding the therapeutic impact of bioptic diagnosis for neuro-AIDS patients, the preoperative treatment attitude was modified in 23/27 cases (85.2%), and the empiric anti-toxoplasmosis regimen was changed or withdrawn in 17/21 patients (81.0%).

CONCLUSION

Our experience demonstrated SBB to be an accurate, manageable, and reasonably safe diagnostic tool in both NIC and AIDS patients. These results suggest also that timely SBB indication in selected AIDS patients, reaching an early diagnosis, may on one side prevent unnecessary and potentially toxic empiric therapeutic regimens, and on the other address the appropriate treatment, thereby improving length and quality of life in such patients.

Palliation of AIDS-related primary lymphoma of the brain: observations from a multi-institutional database

PURPOSE

To catalogue the presenting symptoms of patients with AIDS who are presumed to have primary central nervous system lymphoma (PCNSL). To document the palliative efficacy of cranial irradiation (RT) relative to the endpoints of complete and overall response for the respective symptoms.

METHODS

An analysis of 163 patients with AIDS-related PCNSL who were evaluated at nine urban hospitals was performed. These patients were treated for PCNSL after the establishment of a tissue diagnosis or on a presumptive basis after failing empiric treatment for toxoplasmosis. All patients were treated between 1983 and 1995 with radiotherapy (median dose-fractionation scheme = 3 Gy x 10) and steroids (>90% dexamethasone). Because multiple fractionation schemes were used, prescriptions were converted to biologically effective doses according to the formula, Gy10 = Total Dose x (1 + fractional dose/alpha-beta); using an alpha-beta value of 10.

RESULTS

The overall palliative response rate for the entire group was 53%. In univariate analysis, trends were present associating complete response rates with higher performance status (KPS > or = 70 vs. KPS < or = 60 = 17% vs. 5%), female gender (women vs. men = 29% vs. 8%), and the delivery of higher biologically effective doses (BED) of RT (Gy10 > 39 vs. < or = 39 = 20% vs. 5%). In multivariate analysis of factors predicting complete response, both higher KPS and higher BED retained independent significance. A separate univariate analysis identified high performance status (KPS > or = 70 vs. KPS < or = 60 = 71% vs. 47%), and young age (< or = 35 vs. > 35 = 61% vs. 40%) as factors significantly correlating with the endpoint of the overall response. In multivariate analysis, high performance status and the delivery of higher biologically effective doses of irradiation correlated significantly with higher overall response rates.

CONCLUSION

Most AIDS patients who develop symptoms from primary lymphoma of the brain can achieve some palliation from a management program that includes cranial irradiation. Young patients with excellent performance status are most likely to respond to treatment. The delivery of higher biologically effective doses of irradiation also may increase the probability of achieving a palliative response.

AIDS-related primary brain lymphomas: histopathologic and immunohistochemical study of 51 cases. The French Study Group for HIV-Associated Tumors

Fifty-one cases of acquired immunodeficiency syndrome (AIDS)-related primary brain lymphomas (AR-PBL) were investigated for clinical characteristics; human immunodeficiency virus (HIV)-associated disorders; histopathologic features; immunophenotype; Epstein-Barr virus (EBV) infection; and, when frozen tissue was available, oncogene rearrangements. AR-PBL occurred late in the course of AIDS and were usually associated with other systemic or cerebral disorders and with a low level of CD4 lymphocytes. All cases were high grade lymphomas according to the Working Formulation or updated Kiel classification, and often displayed a multifocal pattern. Thirty cases were classified as immunoblastic with plasmacytic differentiation, 18 cases were large cell lymphomas with an immunoblastic component or centroblastic polymorphic lymphomas, and 2 were small noncleaved non-Burkitt lymphomas (Working Formulation). This latter category is classified as Burkitt's-like lymphoma in the REAL nomenclature. One case could not be classified because of necrosis. AR-PBL showed a high level expression of activation and adhesion molecules. The presence of EBV was detected in most cases, and, when PCR was used, this was a constant finding. bcl-2 oncoprotein and latent membrane protein-1 (LMP-1) were strongly expressed. None of the tested cases expressed p53, or were rearranged for bcl-2 or c-myc oncogenes. This study confirms the immunophenotypic specificity of AR-PBL, which may reflect the special immune status of the brain.

Primary T-cell lymphoma of the brain in acquired immunodeficiency syndrome: case report

In patients with acquired immunodeficiency syndrome (AIDS), primary central nervous system lymphoma (PCNSL) is now the most common noninfectious intracranial mass lesion and the fourth leading cause of death. Most cases of PCNSL are B-cell in origin and are only rarely of T-cell origin. We report the first complete clinical description of T-cell PCNSL in a patient with AIDS. This patient underwent stereotactic biopsy of a cerebellar lesion that demonstrated T-cell lymphoma by immunohistochemical staining. The patient died from opportunistic infection after partial radiation therapy. Complete autopsy revealed no evidence of residual T-cell lymphoma. The authors compare T-cell PCNSL in patients with and without AIDS, and discuss differences between T-cell and B-cell PCNSL. In conclusion, T-cell PCNSL can occur in patients with AIDS. The tumor is often located infratentorially and appears to be radiosensitive. However, the patient's survival is short because death is usually caused by opportunistic infection rather than mass effect from lymphoma.

Biology and management of AIDS-associated primary CNS lymphomas

Primary central nervous system (CNS) lymphoma is the most common brain tumor in patients with AIDS and occurs in about 10% of this population. CT/MR scan usually demonstrates single or multiple contrast enhancing masses that are radiographically indistinguishable from other CNS processes such as toxoplasmosis. Brain biopsy, positive cerebrospinal fluid (CSF) cytology, or possibly the demonstration of Epstein-Barr viral DNA in the CSF can establish the diagnosis. Cranial radiotherapy (RT) has been the cornerstone of therapy and produces responses in most patients, but their median survival is still only a few months. The addition of chemotherapy to RT may prolong survival in a sub-group of patients.

Etiology and pathogenesis of AIDS-related non--Hodgkin's lymphoma

The incidence of NHL is greatly increased in HIV-infected individuals. The vast majority are clinically aggressive B cell-derived neoplasms exhibiting BL, IBL, or LCL histology. Approximately 80% arise systemically (nodal and/or extranodal), and the remaining 20% arise as primary CNS lymphomas. A small proportion are body cavity-based lymphomas associated with KSHV infection. Possible factors contributing to lymphoma development include HIV-induced immunosuppression, chronic antigenic stimulation, and cytokine overproduction. These alterations are associated with the development of oligoclonal B-cell expansions. The appearance of NHL is characterized by the presence of a monoclonal B-cell population displaying a variety of genetic lesions, including EBV infection, c-myc gene rearrangement, bcl-6 gene rearrangement, ras gene mutations, and p53 mutations/deletions. The number and type of genetic lesions varies according to the anatomic site and histopathology. In the case of BL, virtually 100% exhibit c-myc gene rearrangements, two thirds display p53 gene mutations, one third contain EBV, and none exhibit bcl-6 gene rearrangements. In contrast, in the case of IBL, virtually 100% contain EBV, 25% display c-myc gene rearrangements, 20% display bcl-6 gene rearrangements, and very few exhibit p53 gene mutations. These findings suggest that more than one pathogenetic mechanism is operational in the development and progression of AIDS-related NHLs. Further work will be necessary to develop a complete understanding of the etiology and pathogenesis of NHL in the setting of HIV infection. AIDS-related NHL remains an important biologic model for investigating the development and progression of high-grade NHLs as well as NHLs that develop in immune-deficient hosts.