What can oncologists learn from HIV?

The Changing Face of HIV-Associated Malignancies: Advances, Opportunities, and Future Directions

Because of tremendous advances in HIV care, the survival of many people living with HIV (PLWH) now approaches that of the general population. This has led to a shift in the types of malignancies diagnosed among PLWH from AIDS-defining cancers during the height of the HIV epidemic toward more non-AIDS-defining cancers and age-related incidental cancers in the last 2 decades. Despite these trends, positive cancer outcomes still lag behind patients without HIV, and many PLWH never receive appropriate cancer therapy. We explore the reasons for the epidemiologic shift that has been observed, as well as the factors that influence treatment disparities. Furthermore, several studies have demonstrated similar cancer survival rates when PLWH and certain cancers receive the same treatment as those who are HIV-negative. Among possible solutions to improve cancer outcomes include increasing the inclusion of PLWH in clinical trials, using guidelines specific for the treatment of HIV-associated malignancies, and incorporating a multidisciplinary approach to cancer management in PLWH.

Breast Cancer in the Setting of HIV

Oncogenesis in immunocompromised patients occurs due to a number of factors including reduced immune surveillance or other viral pathogens. Breast cancer, unlike other non-AIDS-defining cancers, does not appear associated and has rarely been reported. We describe a case with evidence of immune reactivity around the tumor, but not in the tumor itself.

Human immunodeficiency and Hodgkin lymphoma

Presentation of Hodgkin lymphoma (HL) is distinctive in the infected individual being more advanced, accompanied by B symptoms and the presence of extranodal disease particularly lymphadenopathy of the head and neck. Bone marrow involvement may be found in over 50% of cases. Virtually all co express gamma-herpesvirus. Phenotypically there is prominence of the mixed-cellularity and lymphocyte depleted histopathologic subtypes that define an aggressive clinical course in comparison to other variants. Prior to the induction of cART, median survival was only 1-2 years. Notably the first chemotherapy trial using ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) in 21 patients, without treating the viral infection, resulted in a 43% complete remission rate accompanied by severe haematological toxicities but did not extend median survival with this being 1.5 years matching the negative cases. Significant change accompanied concomitant anti-retroviral therapy that could be given safely even with dose intensive regimens exemplified by BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone) in 12 patients or the Stanford V regimen (doxorubicin, vinblastine, mechlorethamine, etoposide, vincristine, bleomycin, prednisone) coupled with involved-field radiation for bulky disease studied in 59 patients. BEACOPP extended overall survival (OS) to 83% at 2 years. A similar trend was seen when using the Stanford V regimen with an OS rate of 51% at 3 years, disease-free survival (DFS) of 68% and freedom from progression (FFP) in 60%. Additional benefits accrued from supportive care with stimulatory peptides such as G-CSF and when combined with bacterial prophylaxis results approached that found in the uninfected reference group. Current consensus holds this particular lymphoma as still among the non-AIDS defining cancers being lung, stomach, liver or anal despite these having recently gained more attention as several of these neoplasms may be occurring more commonly in the era of cART. While the relative risk of developing a non-AIDS-defining neoplasm in HIV-infected persons on the average is 2-3 times, the risk for developing HL in HIV-infected cases impressively ranges between 5 and 25 times when compared to the general population. Based on the precedent in which Kaposi sarcoma and the non-Hodgkin lymphomas distinctively alter the course of this retroviral infection in a way indistinguishable from concurrent Hodgkin lymphoma we propose that this entity be similarly regarded and the hypothesis tested in large randomised prospective study.

HIV-associated multicentric Castleman's disease

Multicentric Castleman's disease (MCD), a relatively rare lymphoproliferative disorder that presents with heterogenous symptoms including fevers, anemia, and multifocal lymphadenopathy, is today most commonly observed in individuals infected with human immunodeficiency virus type-1 (HIV). In such individuals, a lymph node biopsy typically identifies cells that stain for Kaposi's sarcoma-associated herpesvirus proteins, and most HIV-associated MCD features can be attributed to the presence of this gamma-herpesvirus. Surgery and antiviral therapies including highly active antiretroviral therapy, interferon-alpha, foscarnet, ganciclovir, and antibodies to interleukin-6 have proved largely ineffective, and chemotherapy in HIV positive individuals is complicated by limited efficacy and pronounced toxicity. While no randomized trials have been performed, more recently the use of the anti-CD20 monoclonal antibody rituximab in large single center cohorts has been associated with prolonged remissions, radiologic responses, as well as hematologic and serum chemistry normalization of the inflammatory picture observed, at the expense of B cell depletion and flare of Kaposi's sarcoma. MCD represents a model of disease at the interplay between tumor biology, infection, and immunology.

Relationship of imatinib-free plasma levels and target genotype with efficacy and tolerability

Imatinib has revolutionised the treatment of chronic myeloid leukaemia (CML) and gastrointestinal stromal tumours (GIST). Using a nonlinear mixed effects population model, individual estimates of pharmacokinetic parameters were derived and used to estimate imatinib exposure (area under the curve, AUC) in 58 patients. Plasma-free concentration was deduced from a model incorporating plasma levels of alpha₁-acid glycoprotein. Associations between AUC (or clearance) and response or incidence of side effects were explored by logistic regression analysis. Influence of KIT genotype was also assessed in GIST patients. Both total (in GIST) and free drug exposure (in CML and GIST) correlated with the occurrence and number of side effects (e.g. odds ratio 2.7±0.6 for a two-fold free AUC increase in GIST; P<0.001). Higher free AUC also predicted a higher probability of therapeutic response in GIST (odds ratio 2.6±1.1; P=0.026) when taking into account tumour KIT genotype (strongest association in patients harbouring exon 9 mutation or wild-type KIT, known to decrease tumour sensitivity towards imatinib). In CML, no straightforward concentration–response relationships were obtained. Our findings represent additional arguments to further evaluate the usefulness of individualising imatinib prescription based on a therapeutic drug monitoring programme, possibly associated with target genotype profiling of patients.

Outcome in AIDS-related systemic non-Hodgkin lymphoma and leptomeningeal disease is not predicted by a CT brain scan

BACKGROUND AND PURPOSE

AIDS-related systemic non-Hodgkin lymphoma (ARL) remains a significant cause of morbidity and mortality in patients infected with the human immunodeficiency virus (HIV-1), and leptomeningeal disease in this setting has a dismal prognosis. We investigated the utility of brain CT in determining the outcome of leptomeningeal disease, despite MR imaging being the gold standard.

MATERIALS AND METHODS

From a cohort of 9621 HIV-1-seropositive individuals, we identified those diagnosed with ARL in the highly active antiretroviral therapy (HAART) era who had both a lumbar puncture and central nervous system imaging using a CT brain scan at the time of initial diagnosis, and we compared survival parameters between those with and without leptomeningeal disease.

RESULTS

In a cohort of 82 individuals with ARL treated in the era of HAART, we found that the survival of individuals with leptomeningeal disease defined as the presence of cells in the CSF was worse compared with that of other patients (P = .0026). However, when defined by the presence of abnormal enhancement or parenchymal lesions on a CT scan, the outcome was not significantly different.

CONCLUSION

A CT brain scan appears not to offer additional prognostic information following a lumbar puncture in patients with ARL.

Comparative pharmacogenomics of antiretroviral and cytotoxic treatments

Few genetic markers are used routinely to predict clinical effectiveness and toxic effects despite the fact that physicians and their patients are consistently confronted with this balance. Because one of the goals of pharmacogenomics is to identify individuals and target populations that might have adverse outcomes, pharmaceutical companies have been reluctant to use a strategy that might identify patients who are not eligible for a particular treatment. This view is changing because drug-discovery programmes and treatments that target specific pathways, are showing improvements in surrogate and survival endpoints. HIV and cancer are now regarded as chronic diseases, which commonly need life-long systemic treatment from the time of diagnosis. HIV and cancer medicine have used pharmacogenomics to some extent in clinical care. Common and classic features of pharmacogenomics that are related to both antiretroviral treatment and to cytotoxic treatment are discussed in this review, providing a framework for individual treatment of these diseases.

Noninfectious pulmonary complications of HIV/AIDS

PURPOSE OF REVIEW

This article reviews recent findings on noninfectious pulmonary complications of HIV/AIDS, with a focus on HIV/AIDS-related lung malignancies and pulmonary hypertension, and discusses their incidence in the highly active antiretroviral therapy (HAART) era.

RECENT FINDINGS

Noninfectious pulmonary complications of HIV/AIDS are now recognized as important contributors to morbidity and mortality in HIV-infected patients. This is especially the case for HIV-related lung cancer and other non-AIDS-defining malignancies, which are now being diagnosed with increased frequency in HIV-infected patients. The incidence of Kaposi sarcoma and AIDS-related lymphoma has decreased in the HAART era, but compared with the general population, the risk of these malignancies and pulmonary hypertension is still very high in HIV-infected patients. Concurrent use of HAART and chemotherapy improves prognosis and survival of patients with AIDS-related lymphoma. For patients with HIV-related pulmonary hypertension, some studies show no beneficial effect of HAART whereas other reports show that HAART improves patient survival and response to antihypertensive treatment.

SUMMARY

The beneficial effect of HAART and improved immune response on the treatment of Kaposi sarcoma and AIDS-related lymphoma suggests that HIV or viral-induced immunosuppression plays an important role in the development of these malignancies. Evidence from current studies suggests that HAART does not protect against HIV-related lung cancer. The full impact of HAART on HIV pulmonary hypertension remains to be determined.

The common heat shock protein receptor CD91 is up-regulated on monocytes of advanced melanoma slow progressors

Despite advances in our understanding of tumour immunology there is no therapy of proven survival benefit for advanced melanoma. Nevertheless, disease progression is slow in a small proportion of patients with metastatic melanoma, suggesting a contribution to outcome from host factors. Recent data have indicated the importance of the heat shock protein receptor CD91 in immune responses to, and progression of, infectious disease. Here we investigate the relationship between CD91 expression and outcome in malignancy. Rare melanoma patients were recruited with advanced disease that was progressing unusually slowly. CD91 expression on their monocytes was compared with control patients with more typical rapidly advancing metastatic disease. Th1 and Th2 cytokines, as well as innate and adaptive immune subsets, were also measured in the two groups. A significant increase in median CD91 expression levels was observed in slow progressors (P = 0.006). There were no differences in other immune subset markers or inflammatory cytokines. The ability of CD91 to internalize and cross-present tumour antigens through the major histocompatibility complex class I pathway may maintain CD8-positive cytotoxic T cell responses and contribute to slow progression of advanced melanoma.

Protease inhibitors potentiate chemotherapy-induced neutropenia

Pharmacokinetic interactions between chemotherapy and highly active antiretroviral therapy (HAART) are described, but there are few data on their clinical relevance. Patients with systemic AIDS-related non-Hodgkin lymphoma (ARL) were treated with concomitant HAART and infusional cyclophosphamide-doxorubicin-etoposide (CDE) chemotherapy. We compared neutropenia according to whether patients received protease inhibitor (PI)-based HAART or non-PI regimens. Differences in survival, response rates, immunologic parameters, and virologic parameters were also investigated. The day-10 (Mann-Whitney U test; P = .012) and day-14 (P = .025) neutrophil counts were significantly lower in patients receiving PIs, though there were no differences in the number of days of granulocyte colony-stimulating factor (G-CSF) administered between groups (P = .16). Grade 3 or 4 infections requiring hospitalization were recorded for a total of 58 (31%) of 190 cycles of CDE: 23 (48%) of 48 when prescribed PIs and 35 (25%) of 142 with concomitant PI-sparing HAART (chi(2) test; P = .0025). There were no statistically significant differences in the response rates, relapse-free survival, or disease-free survival between patients receiving PIs and those not receiving PIs. PI-based HAART appears to significantly potentiate the myelotoxicity of CDE chemotherapy. This potentiation may be a consequence of microsomal enzyme inhibition reducing the metabolism of cytotoxics in this regimen.

Antiretroviral Treatment Regimens and Immune Parameters in the Prevention of Systemic AIDS-Related Non-Hodgkin's Lymphoma

Purpose

Immunosuppression induced by HIV-1 increases the risk of developing non-Hodgkin's lymphoma (NHL). We measured the influence of immunologic factors and highly active antiretroviral therapy (HAART) on this risk. As there are no data demonstrating that specific antiretroviral regimens are effective at protecting from NHL, we compared different HAART regimens.

Patients and Methods

The protective effect of HAART regimens, containing protease inhibitors (PI) and/or non-nucleoside reverse transcriptase inhibitors (NNRTIs) on the development of NHL was examined in a prospectively recorded cohort of 9,621 HIV-infected individuals. Lymphocyte and natural killer subset data were also entered in univariate and multivariate analyses to establish and stratify the risk of NHL.

Results

From this cohort of 9,621 patients, 102 have been diagnosed with systemic AIDS-related NHL since 1996, when HAART became freely available here. By univariate analysis, increased age, higher nadir CD4 and CD8 T-cell counts, CD19 B-cell count, CD16/56 natural killer count and exposure to NNRTI or PI containing HAART conferred significant protection against NHL (P < .05). In a multivariate analysis, age, nadir CD4 and CD8 T-cell counts, and exposure to HAART were independent predictors of risk of NHL (P < .02). NNRTI-based HAART (adjusted rate ratio, 0.4; 95% CI, 0.3 to 0.5) was as protective as PI-based HAART, and these were significantly more protective than nucleoside analogues alone (rate ratio, 0.5; 95% CI, 0.4 to 0.7) or no antiretrovirals (P < .001).

Conclusion

Effective HAART-induced maintenance of CD4 and CD8 counts protects from systemic AIDS-related NHL.