Virus-associated human cancers in Moroccan population: From epidemiology to prospective research

Eight human viruses have been classified by the International Agency for Research on Cancer as carcinogenic or probably carcinogenic for humans. Infection with high risk human papillomaviruses, hepatitis B and C viruses, Epstein-Barr virus (EBV), human T-Cell Lymphotropic Virus Type 1 (HTLV-1), Human herpesvirus 8 (HHV-8), Merkel cell polyomavirus and human immunodeficiency virus-1 (HIV1) alone or in combination with other agents are the main etiologic factors of many cancers. This review highlights some aspects of virus-associated human cancers, potentially responsible for >14,000 malignancies per year in Morocco. Given that not all individuals infected with these viruses develop cancer, somatic alterations, genetic predisposition, and lifestyle or environmental factors obviously play potentializing roles modulating viral activity. These viral, host genetic signatures and lifestyle interactions may represent a reservoir of biomarkers for early detection, prevention of cancer and rationale-based therapy.     

West Nile Virus-associated flaccid paralysis outcome

We report 1-year follow-up data from a longitudinal prospective cohort study of patients with West Nile virus-associated paralysis. As in the 4-month follow-up, a variety of recovery patterns were observed, but persistent weakness was frequent. Respiratory involvement was associated with considerable illness and death.     

静脉注射丙种球蛋白佐治婴幼儿病毒相关性喘息的临床研究

目的观察丙种球蛋白佐治婴幼儿病毒相关性喘息的临床疗效及安全性。方法在2010年6月~2011年12月期间某院儿科总收治病毒相关性喘息婴幼儿患儿共102例,随机分为治疗组及对照组各51例,对照组给予常规治疗,治疗组在对照组治疗基础上加用丙种球蛋白250~400mg/kg.d,1次/d,连用3d,比较临床治疗疗效。结果病原学检测结果:呼吸道合胞病毒感染68例(66.67%),流感病毒20例(19.61%),副流感病毒11例(10.78%),其他病毒3例(2.94%);治疗组患儿退热时间、肺部啰音消失时间、咳嗽消失时间、哮鸣音消失时间、住院时间分别为(2.76±0.48)d、(6.24±0.71)d、(7.04±1.13)d、(3.27±0.76)d、(8.82±1.13)d,明显短于对照组(3.98±0.59)d、(8.87±1.02)d、(9.78±2.27)d、(7.25±1.38)d、(12.21±2.43)d,差异有统计学意义(P﹤0.05)。结论病毒相关性喘息的患儿早期使用丙种球蛋白辅助治疗,能取得良好的辅助治疗效果,有利于病情转归。     

Respiratory cancers in furniture workers

In a 19 year follow up study of 8141 furniture workers nasal adenocarcinoma was 63 X 4 times more common than expected. The findings also indicate an excess risk of adenocarcinoma of the maxillary sinus. No increase in risk was found for laryngeal cancer, lung cancer, or sinonasal cancers other than adenocarcinoma.     

Integrative medicine in gynaecological cancers

Gynaecological cancers are the fifth most common cause of cancer death in women in Australia. This article reviews three studies investigating nutritional aspects relating to gynaecological cancers.     

Pythiosis in Africa

We report the first case of pythiosis from Africa in an 8-month-old dog with a chronic and ulcerative cutaneous lesion. The etiologic agent belonged to the genus Pythium. Phylogenetic analysis placed the isolate in a sister group to the other P. insidiosum strains. However, the isolate may belong to a new Pythium species.     

Love in Africa

Research reveals how homophobia and stigma link closely to HIV among men who have sex with men in sub-Saharan Africa. This paper considers the varying impact of homophobic stigma on HIV prevention programmes among men who have sex with men in South Africa. It explores how a community-based HIV prevention programme based in the peri-urban townships of Cape Town was ‘translated’ to peri-urban Johannesburg. Drawing on interviews with volunteers and programme facilitators in Johannesburg, it argues that an altered homophobic environment to that found in Cape Town gave different opportunities to engage both with other men who have sex with men and the broader community. It also argues that programme facilitators should be mindful of how varying degrees of homophobic stigma may relate to broader theoretical debates about sexual binary relationships, which can help us understand why particular programmes choose to focus on certain activities rather than others.     

Malabsorption in Africa

The most spectacular cases of malabsorption in Africa are those often presenting with gross malnutrition and are due to chronic calcific pancreatitis, ileo-caecal tuberculosis, and small-intestinal trauma or resection. Subchnical malabsorption of carbohydrate is numerically a much greater problem. That is usually associated with systemic infection and is not directly related to marginal malnutrition, or an abnormal jejunal mucosa (tropical enteropathy). The evidence that malnutrition produces significant malabsorption is limited to severe cases of kwashiorkor in children. Megaloblastic anaemia due to dietary folate depletion is often associated with an abnormal D-xylose absorption test and the degree of impairment has been shown to correlate with the severity of the anaemia. Intestinal parasites—Strongyloides stercoralis and Giardia lamblia—are occasional causes of malabsorption.Adult hypolactasia is extremely common in African subjects. Although that does not seem to be responsible for significant ill-health in adults, a low lactase concentration is probably important in the pathogenesis of marasmus in infants. Secondary disaccharidase deficiency is an uncommon finding.The evidence for the existence of tropical sprue in Africa has been reviewed. It is rare in Europeans, compared with the high frequency in Asia. There is now some evidence for the existence of chronic tropical sprue in indigenous Africans but that also seems to be less common and is not as florid as it is in Asian people in Asia. The reasons for those differences in incidence rates have been discussed.All causes of malabsorption common to non-tropical areas must be excluded in the individual patient. Of the overt clinical causes in Africa, ileo-caecal tuberculosis is the most difficult to diagnose.     

Common skin cancers

Skin cancers are the most common types of all cancers, and the most commonly occurring skin cancers are basal cell carcinoma, squamous cell carcinoma, and malignant melanoma, in that order. This article discusses the clinical presentations and subtypes of these 3 types of cancer and the current state of treatments for them. Also discussed are precursor lesions to these malignancies, including actinic keratosis, a squamous cell carcinoma precursor, and atypical or dysplastic nevus, a potential precursor of malignant melanoma.     

Occupational skin cancers

Skin cancer due to occupation is more common than is generally recognized, although it is difficult to obtain an accurate estimate of its prevalence. Over the past two centuries, occupational skin cancers have particularly been due to industrial exposure of men (it seems more so than women) to chemical carcinogens such as polycyclic hydrocarbons (e.g. from coal tar products) or to arsenic. Industrial processes have improved in most Western countries to limit this type of exposure, but those with outdoor occupations are still exposed to solar ultraviolet irradiation without this being widely recognized as an industrial hazard. Ionizing radiation such as X-rays can also cause skin cancer. Occupational skin cancers often resemble skin tumours found in non-occupational subjects, e.g. basal cell carcinoma, squamous cell carcinoma and malignant melanoma, but some pre-malignant lesions can be more specific and point to an occupational origin, e.g. tar keratoses or arsenical keratoses. An uncommon but well-recognized cause of occupational skin cancer is that which results from scar formation following an industrial burn. In the future it will be necessary to focus on preventative measures, e.g. for outdoor workers, the need to cover up in the sun and use sun protective creams and a campaign for earlier recognition of skin cancers, which are usually curable if treated in their early stages.     

Respiratory cancers in furniture workers.

In a 19 year follow up study of 8141 furniture workers nasal adenocarcinoma was 63 X 4 times more common than expected. The findings also indicate an excess risk of adenocarcinoma of the maxillary sinus. No increase in risk was found for laryngeal cancer, lung cancer, or sinonasal cancers other than adenocarcinoma.     

Space-time interactions in childhood cancers.

STUDY OBJECTIVE--The aim of the study was to examine a cohort of cases of childhood cancer occurring in a defined geographical area to try to identify clustering and possible causative factors. DESIGN--Data were analysed using the close pair method developed by Knox for signs of clustering in relation to date and place of onset or date and place of birth. SETTING--Cases were those occurring in the 8 year period between 1953 and 1960 in four old counties of the Midlands of England (Worcestershire, Warwickshire, Staffordshire, Shropshire). CASES--418 children under 10 years developed cancers during the study period: leukaemia 228, cerebral tumour 99, neuroblastoma 45, nephroblastoma 46. It is thought that data collection was complete. Cases were matched for region, sex and date of birth with live controls. RESULTS--There was evidence among some age groups and diagnoses of an unexpectedly high number of close pairs of onsets, and some indication of similar patterns among births of children who later developed cancer. The pre- and postnatal experiences of children involved in close pairs were examined to see whether they differed from those of control children. Measles appeared to occur more often in the 2-3 years before the onset of leukaemia in children who were later involved in close pairs than in their matched controls. CONCLUSIONS--Common infectious diseases of childhood may play a minor role in the development of some cancers. Epidemics of these diseases may then be reflected on a greatly reduced scale in the subsequent distribution of cancer cases.     

Clinical implications of angiogenesis in cancers

Angiogenesis plays an important role in the growth and progression of cancer. The regulation of tumor angiogenesis depends on a net balance of angiogenic factors and antiangiogenic factors, which are secreted by both tumor cells and host-infiltrating cells. Numerous studies have indicated that assessment of angiogenic activity by either microvessel density or expression of angiogenic factors in cancer can provide prognostic information independent of conventional clinicopathological factors such as tumor staging. Some studies also suggested that assessment of tumor angiogenesis may predict cancer response to chemotherapy or radiotherapy. However, the most important clinical implication of tumor angiogenesis is the development of a novel strategy of anticancer therapy targeting tumor vessels instead of cancer cells. Antiangiogenic therapy aims to inhibit the growth of tumor, and current evidence suggests that it works best in combination with conventional cytotoxic chemotherapy. Recently, a monoclonal antibody against vascular endothelial growth factor, which is one of the most potent angiogenic factors, has been approved for clinical use in colorectal cancer patients after a clinical trial confirmed that combining the antibody with standard chemotherapy regimen could prolong patient survival. The clinical implications of angiogenesis in cancer are reviewed in this article.     

Rare skin cancers in general practice

Mr LA has long been troubled with actinic damage to his skin, especially his face. He has had many squamous cell carcinomas (SCCs) removed and many solar keratoses managed. On this occasion Mr LA had two actinic lesions on his left cheek that failed to respond to cryotherapy. A biopsy of each site produced a surprise. Histology of the superior lesion revealed sebaceous carcinoma. This is an uncommon yet aggressive cutaneous malignancy derived from sebaceous glands. The 5 year survival rate is 60-70%. The tumour was widely excised with a minimum 10 mm margin. A multidisciplinary approach resulted in a decision not to proceed to adjunctive radiotherapy. The wound was well healed by 8 weeks. Four years on there is no sign of local or regional recurrence.