Diagnosing central nervous system lymphoma in the setting of AIDS: a step forward

Factors associated with survival among patients with AIDS-related primary central nervous system lymphoma

OBJECTIVE

AIDS-related primary central nervous system lymphoma (AR-PCNSL) has a poor prognosis. Improved understanding of specific patient, infectious, diagnostic, and treatment-related factors that affect overall survival (OS) is required to improve outcomes.

DESIGN

Population-based registry linkage study.

METHODS

Adult cases from the San Francisco AIDS registry (1990-2000) were matched with the California Cancer Registry (1985-2002) to ascertain AR-PCNSL data. Survival time was assessed through 31 December 2007. Risk factors and temporal trends for death were measured using two-sided Kaplan-Meier and Cox analyses.

RESULTS

Two hundred and seven AR-PCNSL patients were identified: 68% were white, 20% Hispanic, 10% African-American, and 2% Asian. Nineteen percent of patients had central nervous system (CNS) opportunistic infections diagnosed prior to AR-PCNSL. Fifty-seven percent of patients received radiation and/or chemotherapy and 12% used HAART prior to or within 30 days of AR-PCNSL diagnosis. One hundred and ninety-nine patients died (34 deaths/100 person-years). In adjusted analysis, prior CNS opportunistic infection diagnosis increased risk of death (hazard ratio 1.9, P = 0.0006) whereas radiation and/or chemotherapy decreased risk (hazard ratio 0.6, P < 0.0001). AR-PCNSL diagnosis 1999-2002 had a lower mortality risk (hazard ratio = 0.4, P = 0.02) compared to 1990-1995. African-Americans had an increased risk of death compared to whites or Asians (hazard ratio = 2.0, P = 0.007).

CONCLUSION

OS among AR-PCNSL patients improved over time but remains poor, especially among African-Americans. Prospective evaluation of curative therapy in AR-PCNSL is urgently needed. Accurate diagnosis of CNS mass lesions in patients with AIDS is required and for those with AR-PCNSL, antiretroviral therapy with concomitant AR-PCNSL therapy, and antimicrobial supportive care may improve OS.

Application of molecular diagnostic techniques for viral testing

Nucleic acid amplification techniques are commonly used currently to diagnose viral diseases and manage patients with this kind of illnesses. These techniques have had a rapid but unconventional route of development during the last 30 years, with the discovery and introduction of several assays in clinical diagnosis. The increase in the number of commercially available methods has facilitated the use of this technology in the majority of laboratories worldwide. This technology has reduced the use of some other techniques such as viral culture based methods and serological assays in the clinical virology laboratory. Moreover, nucleic acid amplification techniques are now the methods of reference and also the most useful assays for the diagnosis in several diseases. The introduction of these techniques and their automation provides new opportunities for the clinical laboratory to affect patient care. The main objectives in performing nucleic acid tests in this field are to provide timely results useful for high-quality patient care at a reasonable cost, because rapid results are associated with improvements in patients care. The use of amplification techniques such as polymerase chain reaction, real-time polymerase chain reaction or nucleic acid sequence-based amplification for virus detection, genotyping and quantification have some advantages like high sensitivity and reproducibility, as well as a broad dynamic range. This review is an up-to-date of the main nucleic acid techniques and their clinical applications, and special challenges and opportunities that these techniques currently provide for the clinical virology laboratory.

AIDS-related cancer in the era of highly active antiretroviral therapy (HAART): a model of the interplay of the immune system, virus, and cancer. "On the offensive--the Trojan Horse is being destroyed"--Part B: Malignant lymphoma

The impact of highly active antiretroviral therapy (HAART) on the incidence of non-Hodgkin's lymphoma was less obvious initially, although primary central nervous system lymphoma (PCNSL) has dropped precipitously since the introduction of HAART. The pathogenesis of acquired immunodeficiency syndrome-related lymphoma is multifactorial. Epstein-Barr virus plays a significant role in these diseases, especially Burkitt lymphoma and PCNSL. Data regarding the effect of HAART on the natural history and treatment outcomes of these malignancies are emerging. The possibility of direct and indirect roles of human immunodeficiency virus in the carcinogenesis suggests that antiretroviral therapy may be an important component of the treatment for these malignancies. The simultaneous administration of HAART and chemotherapy does not appear to significantly alter the toxicity profile, although the information with respect to the interaction of HAART and chemotherapy is limited. The use of biological agents, for example, monoclonal antibody against CD-20, is being explored to improve the clinical outcome of this disease.

Predictive Value of Polymerase Chain Reaction of Cerebrospinal Fluid for Detection of Epstein-Barr Virus to Establish the Diagnosis of HIV-Related Primary Central Nervous System Lymphoma

Polymerase chain reaction (PCR) of cerebrospinal fluid (CSF) for detection of Epstein-Barr virus (EBV) DNA has been proposed as a minimally invasive method for establishing the diagnosis of human immunodeficiency virus-related primary central nervous system lymphoma (PCNSL). In a review of the operational characteristics of this test in our clinical practice, the positive predictive value of CSF PCR for EBV for establishing the diagnosis of PCNSL was only 29%. Of 7 patients with CSF PCR positive for EBV, 2 had PCNSL, and 5 received alternative diagnoses (specificity, 79.1%).

Hepatitis C virus-Epstein-Barr virus interaction in patients with AIDS

Immortalization of B cells by Epstein-Barr virus (EBV) and their subsequent proliferation leads to B-cell non-Hodgkin's lymphoma in immunocompromised patients. The role of hepatitis C virus (HCV) in B-cell non-Hodgkin's lymphoma has recently been raised, and an interaction between HCV and EBV is supported by recent in vitro experiments. The aim of this study was to investigate in vivo interactions between HCV and EBV in patients with AIDS, i.e., patients exposed to the risk of EBV-related B-cell non-Hodgkin's lymphoma. A total of 135 patients were prospectively studied. Serological and molecular markers of HCV, EBV, and human immunodeficiency virus (HIV) infection were sought. All the patients harbored latent EBV infection, and 20% had detectable HCV RNA in serum. No significant relationship was found between HIV, HCV, and EBV viral load in peripheral blood mononuclear cells or plasma. There was no difference between anti-HCV-positive and -negative patients or between HCV RNA-positive and -negative patients with regard to the prevalence of EBV markers, especially EBV replication markers. The presence of EBV replication markers was not related to HCV RNA seropositivity or to HCV viral load. Five patients subsequently developed B-cell non-Hodgkin's lymphoma, none of whom had markers of EBV or HCV replication. These results argue against an in vivo interaction between HCV and EBV in patients with AIDS, and against a role of HCV infection in the occurrence of B-cell non-Hodgkin's lymphoma in these patients.

Evaluation of HER2 status: for the treatment of metastatic breast cancers by humanized anti-HER2 Monoclonal antibody (trastuzumab) (Pathological committee for optimal use of trastuzumab)

For the treatment of patients with metastatic breast cancer by humanized anti- human epidermal growth factor receptor type 2 (HER2) antibody (trastuzumab), it is important to evaluate HER2 status adequately. "A guideline for HER2 testing" and "HER2 atlas" produced by the "Pathological committee for optimal use of trastuzumab" are introduced in this report. Appropriate evaluations of biological markers are essential for targeting therapy.

Value of combined approach with thallium-201 single-photon emission computed tomography and Epstein-Barr virus DNA polymerase chain reaction in CSF for the diagnosis of AIDS-related primary CNS lymphoma

PURPOSE

To determine the diagnostic capability of thallium-201 (201Tl) single-photon emission computed tomography (SPECT) combined with Epstein-Barr virus DNA (EBV-DNA) in CSF for the diagnosis of AIDS-related primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

All human immunodeficiency virus (HIV)-infected patients with focal brain lesions observed between June 1996 and March 1998 underwent lumbar puncture and 201Tl SPECT. Each CSF sample was tested with polymerase chain reaction (PCR) for EBV-DNA.

RESULTS

Thirty-one patients were included, 13 with PCNSL and 18 with nontumor disorders. In 11 PCNSL patients, EBV-DNA was positive. Thallium-201 uptake ranged from 1.90 to 4.07 in PCNSL cases (mean, 2.77; 95% confidence interval [CI], 2.35 to 3.19) and from 0.91 to 3.38 in nontumor patients (mean, 1.62; 95% CI, 1.30 to 1.94) (P<.0002). Using a lesion/background ratio of 1.95 as cutoff, a negative SPECT was found in one PCNSL case and 16 nonneoplastic cases. A cryptococcoma and a tuberculoma showed highly increased 201Tl uptake. Epstein-Barr virus DNA was never detected in nonneoplastic patients. For PCNSL diagnosis, hyperactive lesions showed 92% sensitivity and 94% negative predictive value (NPV), whereas positive EBV-DNA had 100% specificity and 100% positive predictive value. The presence of increased uptake and/or positive EBV-DNA had 100% sensitivity and 100% NPV.

CONCLUSION

Combined SPECT and EBV-DNA showed a very high diagnostic accuracy for AIDS-related PCNSL. Because PCNSL likelihood is extremely high in patients with hyperactive lesions and positive EBV-DNA, brain biopsy could be avoided, and patients could promptly undergo radiotherapy or multimodal therapy. On the contrary, in patients showing hypoactive lesions with negative EBV-DNA, empiric anti-Toxoplasma therapy is indicated. In patients with discordant SPECT/PCR results, brain biopsy seems to be advisable.