Epstein-Barr virus and cytomegalovirus in relation to testicular-cancer risk: a nested case-control study

Role of Viral Infections in Testicular Cancer Etiology: Evidence From a Systematic Review and Meta-Analysis

The most represented histotype of testicular cancer is the testicular germ-cell tumor (TGCT), both seminoma and non-seminoma. The pathogenesis of this cancer is poorly known. A possible causal relationship between viral infections and TGCTs was firstly evoked almost 40 years ago and is still a subject of debate. In the recent past, different authors have argued about a possible role of specific viruses in the development of TGCTs including human papillomavirus (HPV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), Parvovirus B-19, and human immunodeficiency virus (HIV). The aim of this present review was to summarize, for each virus considered, the available evidence on the impact of viral infections on the risk of developing TGCTs. The review was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We included all observational studies reported in English evaluating the correlations between viral infections (HPV, CMV, EBV, Parvovirus B19, and HIV) and TGCTs. The methodological quality of studies included in the meta-analysis was evaluated using a modified version of the "Newcastle-Ottawa Scale." Meta-analyses were conducted using the "Generic inverse variance" method, where a pooled odds ratio (OR) was determined from the natural logarithm (LN) of the studies' individual OR [LN (OR)] and the 95% CI. A total of 20 studies (on 265,057 patients) were included in the review. Meta-analysis showed an association with TGCTs only for some of the explored viruses. In particular, no association was found for HPV, CMV, and Parvovirus B-19 infection (p = ns). Conversely, EBV and HIV infections were significantly associated with higher risk of developing TGCTs (OR 7.38, 95% CI 1.89-28.75, p = 0.004; OR 1.71, 95% CI 1.51-1.93, p < 0.00001). In conclusion, we found adequate evidence supporting an oncogenic effect of HIV and EBV on the human testis. Conversely, available data on HPV and TGCTs risk are conflicting and further studies are needed to draw firm conclusions. Finally, current evidence does not support an effect of CMV and Parvovirus B-19 on testicular carcinogenesis.

Role of serum EBV-VCA IgG detection in assessing gastric cancer risk and prognosis in Northern Chinese population

The study aimed to investigate the role of serum EBV‐VCA IgG in assessing gastric cancer (GC) risk and prognosis. A total of 1790 Northern Chinese participants with pathologically confirmed disease underwent EBV‐VCA IgG serologic testing using enzyme‐linked immunosorbent assay (ELISA), including 821 controls, 410 atrophic gastritis (AG) patients, and 559 GC patients. We found that positive EBV‐VCA IgG was significantly associated with GC and its precursor, conferring a 1.55‐ and 1.36‐fold increased risk of GC and AG, respectively (P = 0.001, 95% CI = 1.21‐1.99; P = 0.011, 95% CI = 1.07‐1.72, respectively). The risk effects were more remarkable in younger, female, and Helicobacter pylori‐negative individuals than in older, male, and H. pylori‐positive individuals. EBV‐VCA IgG‐positive subjects had a lower PGI/II ratio than EBV‐VCA IgG‐negative subjects (median 8.0 vs 8.8, P = 0.001), especially those in the H. pylori‐positive (median 6.1 vs 6.8, P = 0.027) and GC subgroups (median 6.4 vs 7.9, P = 0.020). In the intestinal GC subgroup, the survival of EBV‐VCA IgG‐positive patients was worse than that of EBV‐VCA IgG‐negative patients (P = 0.041, HR = 2.45, 95% CI = 1.04‐5.78). Our study suggests that EBV‐VCA IgG seropositivity has potential in predicting the risk of GC and its precursor as well as the prognosis of histologically classified GC.

This is an innovative report about the role of serum EBV‐VCA IgG detection in assessing the risk of gastric cancer (GC) and its precursor as well as GC prognosis. And this is the first report about the relationship between EBV‐VCA IgG serology assay and gastric function status. Our study provides theoretical and experimental basis for evaluating the potential of serum EBV‐VCA IgG as a biomarker in prediction of GC risk and prognosis.

Chemopreventive Strategies for Inflammation-Related Carcinogenesis: Current Status and Future Direction

A sustained and chronically-inflamed environment is characterized by the presence of heterogeneous inflammatory cellular components, including neutrophils, macrophages, lymphocytes and fibroblasts. These infiltrated cells produce growth stimulating mediators (inflammatory cytokines and growth factors), chemotactic factors (chemokines) and genotoxic substances (reactive oxygen species and nitrogen oxide) and induce DNA damage and methylation. Therefore, chronic inflammation serves as an intrinsic niche for carcinogenesis and tumor progression. In this article, we summarize the up-to-date findings regarding definitive/possible causes and mechanisms of inflammation-related carcinogenesis derived from experimental and clinical studies. We also propose 10 strategies, as well as candidate agents for the prevention of inflammation-related carcinogenesis.

Socioeconomic patterning in the incidence and survival of teenage and young adult men aged between 15 and 24 years diagnosed with non-seminoma testicular cancer in northern england

PURPOSE

Previous research from developed countries has shown a marked increase in the incidence of testicular cancer in the past 50 years. This has also been demonstrated in northern England, along with improving 5-year survival. The present study aims to determine if socioeconomic factors may play a role in both etiology and survival from non-seminoma testicular cancer.

MATERIALS AND METHODS

We extracted all 214 cases of non-seminoma testicular cancer diagnosed in teenage and young adult men aged between 15 and 24 years during 1968 to 2006 from the Northern Region Young Persons' Malignant Disease Registry, which is a population-based specialist regional registry. Negative binomial regression was used to examine the relationship between incidence and both the Townsend deprivation score (and component variables) and small-area population density. Cox regression was used to analyze the relationship between survival and both deprivation and population density.

RESULTS

Decreased incidence was associated with living in areas of higher household overcrowding for young adults aged between 20 and 24 years (relative risk per 1% increase in household overcrowding = 0.79; 95% CI: 0.66-0.94) but no association was detected for young people aged between 15 and 19 years. Community-level household unemployment was associated with worse survival (hazard ratio per 1% increase in household unemployment = 1.04; 95% CI: 1.00-1.08).

CONCLUSIONS

This study has shown that increased risk of non-seminoma testicular cancer in teenage and young adult men may be associated with some aspect of more advantaged living. In contrast, greater deprivation is linked with worse survival prospects. The study was ecological by design and so these area-based results may not necessarily apply to individuals.

Significant role of macrophages in human cancers associated with Epstein-Barr virus (Review)

Epstein-Barr virus (EBV) is a ubiquitous pathogen that was first identified as a human cancer virus. Many human cancers are associated with EBV, and we demonstrated that EBV infects macrophages. Macrophages infected with EBV show a close correlation with many human cancers, and thus more attention must be given to the role of macrophages infiltrating into cancer tissues associated with EBV. In this review, I discuss the role of macrophages in the process of EBV-associated oncogenesis with regard to interleukin-10.

Epstein-Barr virus serologic abnormalities and risk of rheumatoid arthritis among women

BACKGROUND

Epstein-Barr virus (EBV) infection and the immune response may be involved in the pathogenesis of rheumatoid arthritis (RA). Past studies have suggested an association between EBV and RA.

METHODS

We studied the association between EBV serologies and RA risk in a nested case-control study in the Nurses' Health Study (NHS) cohorts. We confirmed incident RA cases from 1990 to 2002 by questionnaire and medical record review. Each incident case with blood collected prior to RA symptoms was matched with a healthy participant by time of day and date of blood collection, birth year, menopausal status and postmenopausal hormone use. Immunofluorescence assays measured serologic EBV responses: viral capsid antigen, early-antigen-diffuse and early antigen-complex (restricted and diffuse), Epstein Barr nuclear antigen (EBNA)-1, EBNA-2 and cytomegalovirus (CMV), as control. All were reported as titers, except CMV, which was reported as positive or negative. Antinuclear antibody positive samples were excluded. Elevated EBV antibody titers were defined as the upper 20% (or nearest titer) among controls. Conditional logistic regression analyses modeled RA risk associated with elevated EBV titers or the presence/absence of CMV, further adjusted for pack-years smoking and alcohol intake.

RESULTS

Eighty-seven incident RA cases were identified. Mean time to RA after blood draw was 6.2 (± 3.5) years in NHS and 1.9 (± 0.6) years in NHS II. Antibody titers against EBV were not significantly different between pre-RA cases and controls.

CONCLUSIONS

In this prospective study of women, we observed no association between EBV serologies and RA risk.

International trends in the incidence of testicular cancer, 1973-2002

BACKGROUND

Whereas testicular cancer incidence rates have been widely reported in populations of Northern European ancestry, rates in other populations have been less frequently examined. In a prior report, global testicular cancer incidence rates and trends for the years 1973 to 1997 were summarized. The current report extends these analyses with an additional 5 years of data from Cancer Incidence in Five Continents.

METHODS

Age-standardized incidence rates over successive 5-year time periods were obtained for populations in the Americas, Asia, Europe, and Oceania.

RESULTS

In general, testicular cancer incidence remained highest in Northern European populations (8.0-9.0 per 100,000) and lowest in Asian and African populations (<1 per 100,000). One notable exception to this pattern, however, was the very high rate reported by the Valdivia, Chile registry (8.8 per 100,000). In many populations, rates rose between 1973 and 2002, although the increases were strongest and most consistent among populations of European ancestry. In certain European populations, such as those of Denmark and of Geneva, Switzerland, some recent plateauing of rates was evident. There was little evidence of increase and possible evidence of a modest decline in rates among east Asian populations. Trends by histology (seminoma and nonseminoma) were generally similar to one another.

CONCLUSIONS

Risk of testicular cancer remains relatively high in Northern European populations and low in Asian and African populations. Similar trends by histology suggest common risk factors. EFFECT: Reasons for increasing rates among Northern Europeans and stable or declining rates among East Asians are unexplained, supporting the need for future etiologic studies.

Multiple oncogenic viruses identified in Ocular surface squamous neoplasia in HIV-1 patients

BACKGROUND

Ocular surface squamous neoplasia (OSSN) is a rare cancer that has increased in incidence with the HIV pandemic in Africa. The underlying cause of this cancer in HIV-infected patients from Botswana is not well defined.

RESULTS

Tissues were obtained from 28 OSSN and 8 pterygia patients. The tissues analyzed from OSSN patients were 83% positive for EBV, 75% were HPV positive, 70% were KSHV positive, 75% were HSV-1/2 positive, and 61% were CMV positive by PCR. Tissues from pterygium patients were 88% positive for EBV, 75% were HPV positive, 50% were KSHV positive, and 60% were CMV positive. None of the patients were JC or BK positive. In situ hybridization and immunohistochemistry analyses further identified HPV, EBV, and KSHV in a subset of the tissue samples.

CONCLUSION

We identified the known oncogenic viruses HPV, KSHV, and EBV in OSSN and pterygia tissues. The presence of these tumor viruses in OSSN suggests that they may contribute to the development of this malignancy in the HIV population. Further studies are necessary to characterize the molecular mechanisms associated with viral antigens and their potential role in the development of OSSN.

Etiologic factors in testicular germ-cell tumors

Globally, testicular cancer incidence is highest among men of northern European ancestry and lowest among men of Asian and African descent. Incidence rates have been increasing around the world for at least 50 years, but mortality rates, at least in developed countries, have been declining. While reasons for the decreases in mortality are related to improvements in therapeutic regimens introduced in the late 1970s, reasons for the increase in incidence are less well understood. However, an accumulating body of evidence suggests that testicular cancer arises in fetal life. Perinatal factors, including exposure to endocrine-disrupting chemicals, have been suggested to be related to risk.

Epstein-Barr virus antibody level and gastric cancer risk in Korea: a nested case-control study

Background:

Few cohort studies have investigated Epstein–Barr virus (EBV) infection before the occurrence of gastric cancer.

Methods:

Among 14 440 cohort participants, 100 incident gastric cancer cases were individually matched to two controls. Epstein–Barr virus antibodies IgG and IgA against viral capsid antigen (VCA), EBV nuclear antigen (EBNA) antibody IgG, and early antigen (EA) antibody IgG were measured using enzyme immunoassays (EIAs).

Results:

The highest titres of VCA IgG (odds ratio (OR): 1.37, 95% confidence interval (CI): 0.62–3.06) or EBNA IgG (OR: 0.87, 95% CI: 0.51–1.46) were not associated with gastric cancer risk.

Conclusion:

Higher levels of VCA IgG or EBNA IgG were not associated with increased risk of gastric adenocarcinoma in Koreans.

Maternal Epstein-Barr virus and cytomegalovirus infections and risk of testicular cancer in the offspring: a nested case-control study

During recent decades the incidence of testicular cancer (TC) has increased rapidly around the world. Associated exogenous etiological factors might therefore be identifiable. We performed a case-control study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of congenital or neonatal infections with Epstein-Barr virus (EBV) and cytomegalovirus (CMV) as risk factors of TC in the offspring. For each case-index mother pair, three or four matched control-control mother pairs were identified using national population registries. First trimester sera were retrieved from the index mothers of 66 TC cases and 258 matched control mothers, and were tested for antibodies to EBV and CMV. High level of maternal EBV IgG antibodies was associated with significantly increased risk of TC in the offspring (odds ratio (OR), 2.50; 95% confidence interval (CI), 1.15, 5.40), especially with risk of non-seminoma TC (OR, 2.73; 950% CI, 1.25, 5.99) and non-seminoma TC diagnosed under 8 years of age (OR, 2.72; 95% CI, 1.05, 7.04). In contrast, offspring of CMV IgG-seropositive mothers had a decreased risk of TC diagnosed under 8 years of age (OR, 0.35; 95% CI, 0.14, 0.89). Our results suggest that EBV and CMV infections may be associated with TC.

Associations between Burkitt lymphoma among children in Malawi and infection with HIV, EBV and malaria: results from a case-control study

BACKGROUND

Burkitt lymphoma, a childhood cancer common in parts of sub-Saharan Africa, has been associated with Epstein Barr Virus (EBV) and malaria, but its association with human immunodeficiency virus (HIV) is not clear.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a case-control study of Burkitt lymphoma among children (aged < or = 15 years) admitted to the pediatric oncology unit in Blantyre, Malawi between July 2005 and July 2006. Cases were 148 children diagnosed with Burkitt lymphoma and controls were 104 children admitted with non-malignant conditions or cancers other than hematological malignancies and Kaposi sarcoma. Interviews were conducted and serological samples tested for antibodies against HIV, EBV and malaria. Odds ratios for Burkitt lymphoma were estimated using unconditional logistic regression adjusting for sex, age, and residential district. Cases had a mean age of 7.1 years and 60% were male. Cases were more likely than controls to be HIV positive (Odds ratio (OR)) = 12.4, 95% Confidence Interval (CI) 1.3 to 116.2, p = 0.03). ORs for Burkitt lymphoma increased with increasing antibody titers against EBV (p = 0.001) and malaria (p = 0.01). Among HIV negative participants, cases were thirteen times more likely than controls to have raised levels of both EBV and malaria antibodies (OR = 13.2; 95% CI 3.8 to 46.6; p = 0.001). Reported use of mosquito nets was associated with a lower risk of Burkitt lymphoma (OR = 0.2, 95% CI, 0.03 to 0.9, p = 0.04).

CONCLUSIONS

Our findings support prior evidence that EBV and malaria act jointly in the pathogenesis of Burkitt lymphoma, suggesting that malaria prevention may decrease the risk of Burkitt lymphoma. HIV may also play a role in the etiology of this childhood tumor.

Hypothesis--ultraviolet-B irradiance and vitamin D reduce the risk of viral infections and thus their sequelae, including autoimmune diseases and some cancers

Many viral infections reach clinical significance in winter, when it is cold, relative humidity is lowest and vitamin D production from solar ultraviolet-B irradiation is at its nadir. Several autoimmune diseases, such as multiple sclerosis, type 1 diabetes mellitus and asthma, are linked to viral infections. Vitamin D, through induction of cathelicidin, which effectively combats both bacterial and viral infections, may reduce the risk of several autoimmune diseases and cancers by reducing the development of viral infections. Some types of cancer are also linked to viral infections. The cancers with seemingly important risk from viral infections important in winter, based on correlations with increasing latitude in the United States, an index of wintertime solar ultraviolet-B dose and vitamin D, are bladder, prostate, testicular and thyroid cancer, Hodgkin's and non-Hodgkin's lymphoma, and, perhaps, gastric cancer. The evidence examined includes the role of viruses in the etiology of these diseases, the geographic and seasonal variation of these diseases, and the time of life when vitamin D is effective in reducing the risk of disease. In general, the evidence supports the hypothesis. However, further work is required to evaluate this hypothesis.

A case-control investigation of immune function gene polymorphisms and risk of testicular germ cell tumors

There is reason to suspect that testicular germ cell tumor (TGCT) development may be influenced by cytokines, secreted proteins that modulate tumor immune surveillance activity as well as a variety of processes in the testis. To address this hypothesis, we conducted a case-control analysis (508 cases, 608 controls) of 32 putatively functional single-nucleotide polymorphisms (SNP) in 16 immune function genes among non-Hispanic Caucasian participants in the U.S. Servicemen's Testicular Tumor Environmental and Endocrine Determinants Study. The TGFB1 Ex5-73C>T variant was positively associated with TGCT (CT/TT versus CC: odds ratio, 1.73; 95% confidence interval, 1.01-2.95; P(trend) = 0.05); additionally, haplotypes of the assessed TGFB1 SNPs (-509C>T, 327C>T, Ex1-282C>G, and Ex5-73C>T) differed in frequency between cases and controls (all TGCT, P 0.07; seminoma, P 0.04; nonseminoma, P 0.11). We also observed excess frequencies among TGCT cases versus controls of LTA 252G (P(trend) = 0.08) and of the TNF variants -1042C (P(trend) = 0.06), -1036T (P(trend) = 0.07), and -238G (P(trend) = 0.09). Analyses of haplotypes for LTA-TNF SNPs (LTA -91C>A, LTA 252A>G, TNF -863C>A, TNF -857C>T, TNF -308G>A, and -238G>A) were similarly suggestive of an association with TGCT (P = 0.06) and nonseminoma (P = 0.04), but not seminoma (P = 0.21). Polymorphisms in other genes were found to be associated only with seminoma (IL2) or nonseminoma (IFNGR2 and IL10). However, none of the associations remained noteworthy after applying the false discovery rate method to control for multiple testing. In conclusion, our findings suggest that polymorphisms in TGFB1 and LTA/TNF, and possibly other immune function genes, may influence susceptibility to TGCT.

Space-time clustering analyses of testicular cancer amongst 15-24-year-olds in Northern England

There has been speculation that environmental exposures may be involved in the aetiology of testicular cancer in adolescent boys and young men. Indirect evidence for this hypothesis would be provided by the finding of space-time clustering. To examine this we have looked for evidence of space-time clustering using data from a population-based cancer registry from Northern England. All cases of testicular cancer diagnosed in males aged 15-24 years during the period 1968-2002 were included in the study. Tests for space-time interactions between cases were applied with fixed thresholds of close in space and close in time. Addresses at birth and diagnosis were used in the analyses. To adjust for the effect of varying population density tests were repeated replacing fixed geographical distances with nearest neighbour thresholds. A total of 257 cases of testicular cancer were identified for analysis. Overall there was no evidence for space-time clustering. However, there was statistically significant space-time clustering for 15-19-year-old based on time of birth and place of diagnosis (p<0.001). The very limited finding of space-time clustering may provide tentative evidence for an environmental, or infectious component to aetiology. However, it may well be a chance finding. A larger study based on national data is required.

A prospective study of Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus in adults with human immunodeficiency virus-1

Antibody titres against Kaposi's sarcoma associated herpesvirus (KSHV or human herpesvirus 8 (HHV-8)) and Epstein–Barr virus (EBV) were examined in people who subsequently developed Kaposi's sarcoma and non-Hodgkin's lymphoma, within randomised controlled trials of antiretroviral therapy in adults infected with the human immunodeficiency virus-1 (HIV). For each case of Kaposi's sarcoma (n=189) and each case of non-Hodgkin's lymphoma (n=67), which developed after randomisation, one control was randomly selected from other trial participants, after matching for age, sex, ethnicity, mode of HIV transmission, type of treatment received and period of follow-up. Using sera taken an average of two and a half years before the diagnosis of cancer, titres of antibodies against KSHV latent (LANA) and lytic (K8.1) antigens and against EBV (VCA) antigens were investigated in relation to subsequent risks of cancer by calculating odds ratios (OR) using conditional logistic regression. Latent antibodies against KSHV were detectable among 38% (72 out of 189) of Kaposi's sarcoma cases and 12% (23 out of 189) of their controls (OR=4.4, 95% confidence intervals (CI) 2.3–8.3, P<0.001). The OR for Kaposi's sarcoma increased with increasing antilatent KSHV antibody titre (χ²₁ for trend=32.2, P<0.001). Lytic antibodies against KSHV were detectable among 33% (61 out of 187) of Kaposi's sarcoma cases and 19% (36 out of 187) of their controls (OR=2.0, 95% CI 1.2–3.4, P=0.003) and the OR for Kaposi's sarcoma increased with increasing antilytic KSHV antibody titre (χ²₁ for trend=6.2, P=0.02). Virtually, all cases and controls had anti-EBV antibodies detected and the OR for non-Hodgkin's lymphoma associated with a doubling of the anti-EBV antibody titre was estimated to increase by a multiplicative factor of 1.3 (95% CI 0.9–1.7, P=0.1). Kaposi's sarcoma was not associated with antibody levels against EBV (P=0.4) and non-Hodgkin's lymphoma was not associated with antibodies against KSHV (latent P=0.3; lytic P=0.5). Adjustment for CD4 count at the time of sample collection made no material difference to any of the results. In conclusion, among human immunodeficiency virus infected people, high levels of antibodies against KSHV latent and lytic antigens are strongly associated with subsequent risk of Kaposi's sarcoma but not non-Hodgkin's lymphoma. Antibody titre to EBV does not appear to be strongly associated with subsequent risk of Kaposi's sarcoma or non-Hodgkin's lymphoma in HIV infected people.

Update on non-acquired immunodeficiency syndrome-defining malignancies

PURPOSE OF REVIEW

Since the introduction of highly active antiretroviral therapy (HAART), the natural history of human immunodeficiency virus (HIV) infection has changed. Early in the acquired immunodeficiency syndrome (AIDS) epidemic, epidemiologic studies showed that HIV-infected patients were at higher risk for developing specific AIDS-defining malignancies. More recent studies linking HIV/AIDS databases to cancer registries have shown that HIV-infected patients are also at higher risk of developing non-AIDS-defining malignancies. We review the most recent data regarding clinical presentation, pathology, and treatment outcomes for these non-AIDS-defining malignancies.

RECENT FINDINGS

Recent large cohort studies linking HIV/AIDS databases to cancer registries have shown that HIV-infected patients are also at higher risk of developing non-AIDS-defining malignancies. Besides anal cancer and Hodgkin disease, the cohort studies have identified other malignancies that appear to occur at a higher rate in the HIV-infected population as compared with the general population. These malignancies include lung cancer, skin cancer, germ cell tumors, leiomyosarcomas, cancers of the head and neck, conjunctival cancer, multiple myeloma, and leukemias.

SUMMARY

As the epidemiology of non-AIDS-defining malignancies continues to evolve, it is unclear whether the appropriate treatments and outcomes for these or other malignancies are changed for HIV-infected patients treated with HAART.

Nested case-control study on the risk factors of colorectal cancer

AIM: To investigate the risk factors of colon cancer and rectal cancer.

METHODS: A nested case-control study was conducted in a cohort of 64693 subjects who participated in a colorectal cancer screening program from 1989 to 1998 in Jiashan county, Zhejiang, China. 196 cases of colorectal cancer were detected from 1990 to 1998 as the case group and 980 non-colorectal cancer subjects, matched with factors of age, gender, resident location, were randomly selected from the 64693 cohort as controls. By using univariate analysis and mutivariate conditional logistic regression analysis, the odds ratio (OR) and its 95% confidence interval (95%CI) were calculated between colorectal cancer and personal habits, dietary factors, as well as intestinal related symptoms.

RESULTS: The mutivariate analysis results showed that after matched with age, sex and resident location, mucous blood stool history and mixed sources of drinking water were closely associated with colon cancer and rectal cancer, OR values for the mucous blood stool history were 3.508 (95%CI: 1.370-8.985) and 2.139 (95%CI: 1.040-4.402) respectively; for the mixed drinking water sources, 2.387 (95%CI: 1.243-4.587) and 1.951 (95%CI: 1.086-3.506) respectively. All reached the significant level with a P-value less than 0.05.

CONCLUSION: The study suggested that mucous blood stool history and mixed sources of drinking water were the risk factors of colon cancer and rectal cancer. There was no any significant association between dietary habits and the incidence of colorectal cancer.

Testicular carcinoma and HLA Class II genes

BACKGROUND

The association with histocompatibility antigens (HLA), in particular Class II genes (DQB1, DRB1), has recently been suggested to be one of the genetic factors involved in testicular germ cell tumor (TGCT) development. The current study, which uses genotyping of microsatellite markers, was designed to replicate previous associations.

METHODS

In 151 patients, along with controls comprising parents or spouses, the HLA region (particularly Class II) on chromosome 6p21 was genotyped for a set of 15 closely linked microsatellite markers.

RESULTS

In both patients and controls, strong linkage disequilibrium was observed in the genotyped region, indicating that similar haplotypes are likely to be identical by descent. However, association analysis and the transmission disequilibrium test did not show significant results. Haplotype sharing statistics, a haplotype method that derives extra information from phase and single marker tests, did not show differences in haplotype sharing between patients and controls.

CONCLUSION

The current genotyping study did not confirm the previously reported association between HLA Class II genes and TGCT. As the HLA alleles for which associations were reported are also prevalent in the Dutch populations, these associations are likely to be nonexistent or much weaker than previously reported.

No association between human parvovirus B19 and testicular germ cell cancer

The incidence of testicular germ cell cancer, which is the most common cancer among young male adults, is increasing. The aetiology remains unknown, although a virus has been proposed. A previous study has shown a high prevalence of human parvovirus B19 (B19) DNA in the testes of patients with testicular germ cell tumours (85%) and suggested that B19 may play a role in tumour development. To address this question of causality, seroreactivity to B19 was studied among cases (n=80) and controls (n=241) using serum samples drawn before the onset of disease, in addition to an elucidation of the frequency of virus DNA in a retrospectively collected 2-year testicular carcinoma series. No association was found between B19 seropositivity and the risk of testicular cancer (odds ratio=1.03; 95% confidence interval=0.60-1.77) nor was there any dose-response relation (P for trend=0.53). This study did, however, confirm the observation that B19 DNA can be detected in testicular carcinoma tissue, as 4 of 24 cases were found to be positive, while no B19 DNA could be detected in the control cases. It is speculated that this finding may be due to susceptibility of the carcinoma cells to B19 virus owing to high-level expression of the viral receptor glycosphingolipid (Gb4) and possible other putative cellular factors resulting in a localized persistence initiated after the development of cancer.

Germ cell tumors in patients infected by the human immunodeficiency virus

BACKGROUND

The objective of this study was to assess the natural history of the two disease courses, patient immune system tolerance, and results of therapy in human immunodeficiency virus (HIV)-infected patients with germ cell tumors (GCT).

METHODS

From 1985 to 1996, 34 HIV-infected men received a diagnosis of GCT. Their charts were analyzed retrospectively.

RESULTS

Sixteen patients had seminomas, and 18 had nonseminomatous GCTs (NSGCT); 71% had International Union Against Cancer (UICC), 1997 Stage I-II GCTs. At the time of chemotherapy, 69%, 6%, and 25% of patients with advanced NSGCT were in the International Germ Cell Consensus Classification (IGCCC) good, intermediate, and poor prognostic group, respectively. All except 1 of the 10 patients with advanced seminomas were in the IGCCC good prognostic group. At diagnosis of GCT, 85% of patients were classified as having asymptomatic HIV infection or only persistent generalized lymphadenectomy. The median CD4 cell count was 325/microL (range, 6-1125). Overall, 26 patients were given chemotherapy, but the planned dose intensity was respected in only 15 (57%) patients. Severe toxic effects included febrile neutropenia in 35% of patients. During chemotherapy, zidovudine, prophylactic granulocyte colony-stimulating factor (G-CSF), and a Pneumocystis carinii prophylaxis were given in 19%, 23%, and 35% of cases, respectively. CD4 cell count decreased in 7 (64%) of 11 patients during chemotherapy. Infradiaphragmatic radiotherapy was given in 10 cases and was clinically well tolerated. At a median follow-up of 27 months (range, 3-150), 50% of patients were alive, and only 18% of patients died of GCT. Two patients developed a non-GCT malignancy while in complete remission, namely, Hodgkin disease and an acute leukemia.

CONCLUSIONS

The prognosis of GCT in HIV-infected patients is mostly dictated by the HIV infection. Patients should be treated according to stage and histologic subtype, although dose reduction of chemotherapy might be necessary in approximately half of the patients. Close surveillance of neutrophil and CD4 cells counts, as well as the use of G-CSF and systematic anti-Pneumocystis carinii prophylaxis are recommended during chemotherapy. The use of highly active antiretroviral therapy during chemotherapy for GCT requires a prospective assessment.

Prognostic parameters for the management of advanced testis tumours

The need for prognostic parameters in testicular germ cell tumours is sometimes questioned based on an overall cure rate of more than 80% of the patients regardless of tumour stage. However, the trend for an earlier and more accurate diagnosis amenable to curative treatment as well as the high effectiveness of standard Cisplatinum containing chemotherapy has masked the continuing need for intensifying therapy in patients with adverse risk factors. This intense treatment is often associated with worrysome morbidity and the assessment of prognostic factors, stage by stage, is warranted on which patient at risk can be identified and treated accordingly. Traditional prognostic factors, on which most classification systems are based, include large tumour volume, the presence of liver, bone or brain metastasis, grossly elevated tumour markers and an extragonadal primary site, particularly in the mediastinum. Novel prognostic factors are either (1) independent from the patient and his disease, (2) inherent on the patient's characteristics or (3) based on tumour biology. Clearly, the infrastructure and the experience of the treating uro-oncology unit (see 1) is decisive for treatment outcomes, and -at least-'difficult to treat' patients should be referred to properly resourced cancer centres. Patients with higher socio-economic status, willing to travel and well educated enough to be worried about their diseases status apparently gain access to expert centres more easily (see 2), translating into an upgrade on prognosis. Finally, biologic factors (see 3) such as beta-human chorionic gonadotrophin or MAGE epitopes in seminoma or the percentage of embryonal carcinoma components orvascular invasion mayor may not inversely influence the prognosis and need further assessment in prospective trials. However, the search for even better (molecular) biologic factors is speeding up because more complex treatment decisions such as in advanced testicular cancers rely on a more precise determination of prognosis, enabling a more tailored selection of individualized therapeutic options.