Human Schistosomiasis mansoni associated with hepatocellular carcinoma in Egypt: current perspective

From the discovery of helminths to the discovery of their carcinogenic potential

Cancer involves a major aberration in the normal behaviour of cells, making them divide continuously, which interferes with the normal physiology of the body. The link between helminths and their cancer-inducing potential has been proposed in the last century. The exact pathway is still not clear but chronic inflammation in response to the deposited eggs, immune response against soluble egg antigens, and co-infection with a third party (a bacteria, a virus, or infection leading to a change in microbiome) seems to be the reasons for cancer induction. This review looks into the historical outlook on helminths along with their epidemiology, morphology, and life cycle. It then focuses on providing correlations between helminth infection and molecular mechanism of carcinogenesis by elaborating upon epidemiological, clinical, and surgical studies. While the cancer-inducing potential has been convincingly established only for a few helminths and studies point out towards possible cancer-inducing ability of the rest of the helminths elucidated in this work, however, more insights into the immunobiology of helminths as well as infected patients are required to conclusively comment upon this ability of the latter.

The prevalence rate, mortality, and 5-year overall survival of Schistosoma japonicum patients with human malignancy

Background

Only a few studies have focused on the association between Schistosoma japonicum and human malignancy. The aim of this study was to update the prevalence rate, mortality, and 5-year overall survival of S. japonicum patients with human malignancy.

Methods

From January 20, 2018, to January 31, 2021, 5,866 inpatients were included in the study. A total of 656 S. japonicum patients with malignancy were identified. Cases were stratified by gender and age groups. The cancer sites, prevalence rate, mortality, and 5-year overall survival of the patients were reported. The S. japonicum patients with malignancy were further divided into a non-digestive system tumor group (n = 309) and a digestive system tumor group (n = 347), including those with cancer in the esophagus, stomach, colon, rectum, liver, gallbladder, bile duct, or pancreas. Chi-squared test and odds ratio with confidence intervals were performed between these two groups.

Results

Lung cancer was found the most common malignancy, accounting for 18.6% of all malignancies, followed by colorectal, stomach, liver, and gallbladder cancers. These five leading malignancies accounted for approximately 61.8% of all cases. Colorectal cancer was the leading cause of malignancy death, followed by lung, stomach, gallbladder, and liver cancers. These five leading causes of death accounted for approximately 55.6% of all death cases. Statistical significance was found in the prevalence rate between S. japonicum and non-S. japonicum patients with/without digestive system tumor (p < 0.001). The odds ratio of S. japonicum patients with digestive system tumors was 1.6 (95%CI: 1.4-1.9).

Conclusion

S. japonicum contributes to a significant prevalence and mortality in digestive system tumors, including colorectal, stomach, liver, and gallbladder cancers.

HEPATOSPLENIC SCHISTOSOMIASIS-ASSOCIATED CHRONIC PORTAL VEIN THROMBOSIS: RISK FACTOR FOR HEPATOCELLULAR CARCINOMA?

BACKGROUND

Hepatosplenic schistosomiasis is an endemic disease prevalent in tropical countries and is associated with a high incidence of portal vein thrombosis. Inflammatory changes caused by both parasitic infection and portal thrombosis can lead to the development of chronic liver disease with potential carcinogenesis.

AIMS

To assess the incidence of portal vein thrombosis and hepatocellular carcinoma in patients with schistosomiasis during long-term follow-up.

METHODS

A retrospective study was conducted involving patients with schistosomiasis followed up at our institution between 1990 and 2021.

RESULTS

A total of 126 patients with schistosomiasis were evaluated in the study. The mean follow-up time was 16 years (range 5-31). Of the total, 73 (57.9%) patients presented portal vein thrombosis during follow-up. Six (8.1%) of them were diagnosed with hepatocellular carcinoma, all with portal vein thrombosis diagnosed more than ten years before.

CONCLUSIONS

The incidence of hepatocellular carcinoma in patients with schistosomiasis and chronic portal vein thrombosis highlights the importance of a systematic long-term follow-up in this group of patients.

Cancer Screening in Refugees and Immigrants: A Global Perspective

Clinicians in the United States are trained to screen for cancer based on patient age, gender, family history, and environmental risk factors such as smoking. These cancers generally include, breast, cervical, colon, lung, and prostate cancers. We know that refugees and other immigrants to the United States experience dramatic disparities in cancer screening. Additionally, many immigrants experience elevated risks from infection-attributable cancers due to their country or region of origin. U.S.- based clinicians may not routinely consider these unique risk factors. Although this article focuses on refugees, it is also intended to guide clinicians caring for other foreign-born immigrant groups living in the United States (hereafter referred to as "immigrants"). The document contains two sections: 1) special considerations for U.S. Preventive Services Task Force guidelines cancer screening recommendations in immigrants and 2) cancer risks and screening recommendation unique to certain immigrant groups. Disparities in cancer screening and prevalence are often greater for specific immigrant groups than for broader racial or ethnic groups (e.g., Black, Asian, Hispanic) into which they may fit. Disaggregation of data by language or country of origin is useful to identify such disparities and to design intervention opportunities within specific communities that are culturally distinct and/or who have different environmental exposures. Unique cancer risks and disparities in screening support a nuanced approach to cancer screening for immigrant and refugee populations, which is the focus of this narrative review.

Liver Disease Outcomes after Sustained Virological Response in Patients with Chronic Hepatitis C Infection Treated with Generic Direct-Acting Antivirals

The introduction of generic direct-acting antivirals (DAAs) in Egypt is associated with a superior cure rate of hepatitis C virus (HCV) infection. However, the course of progressive liver damage and developing liver related complications in patients with sustained virologic response (SVR) remain unclear. This study was designed to examine the long-term outcomes of generic DAA-induced virological cure in a real-life cohort of HCV patients with or without comorbid schistosomiasis. We prospectively enrolled a cohort of 506 recently cured HCV patients (437 Child-Pugh class A [Child-A] and 69 Child-Pugh class B [Child-B]). All patients were clinically evaluated at different time points during a 2-year follow-up (November 2018 to February 2021). Over the course of treatment and follow-up, 77 (15.2%) patients (42 [9.6%] Child-A and 35 [50.7%] Child-B) experienced complications at different time points. The overall mortality rate was approximately 1/1,000 person-years. The incidence of hepatic insufficiency was approximately 5.5/1,000 person-years, and that of de novo hepatocellular carcinoma (HCC) was approximately 8.3/1,000 person-years. A sustained improvement in liver indices up to 2 years of follow-up was observed. In the Cox regression model, pretreatment decompensated cirrhosis predicted the occurrence of adverse liver events and HCC after therapy. In conclusion, in HCV patients with advanced cirrhosis or coexisting hepatic schistosomiasis, generic DAA-induced SVR remains robust with favorable clinical outcomes although the risk of hepatocarcinogenesis cannot be eliminated. Surveillance of patients with treated HCV infection is an important aspect of postcure care for early detection and management of liver disease-related adverse events.

Schistosoma mansoni infection and the occurrence, characteristics, and survival of patients with hepatocellular carcinoma: an observational study over a decade

Schistosoma mansoni infection (SMI) is suspected to be directly and indirectly involved in hepato-carcinogenesis. This study evaluated the association of a previous SMI with hepatocellular carcinoma (HCC) development, patients, tumor characteristics, treatment outcomes, and survival. This observational study included patients with HCC with and without previous SMI who presented to the multidisciplinary HCC clinic, Kasr-Alainy hospital (November 2009 to December 2019). It also included 313 patients with liver cirrhosis without HCC. Clinical and laboratory features of the patients (complete blood count, liver/renal functions , alpha-fetoprotein, and hepatitis B/C status), tumor characteristics (Triphasic CT and/or dynamic MRI), liver stiffness (transient elastography), HCC treatment outcome, and overall survival were studied. This study included 1446 patients with HCC; 688(47.6%) composed group-1, defined by patients having a history of SMI, and 758(52.4%) were in group-2 and without history of SMI. Male sex, smoking, diabetes mellitus, splenomegaly, deteriorated performance status, synthetic liver functions, and platelet count were significantly higher in group-1. The groups did not differ with regard to liver stiffness, tumor characteristics, or the occurrence of post-HCC treatment hepatic decompensation or recurrence. HCC treatment response was better in group-2. Group-1 showed lower sustained virological response to hepatitis C direct-acting antivirals (DAAs) compared with group-2 (60% versus 84.3%, respectively, P = 0.027). Prior SMI was associated with HCC (adjusted odds ratio = 1.589, 95% confidence interval = 1.187-2.127), and it was concluded that it increases the risk of HCC. In addition, it significantly affects the performance status, laboratory characteristics, response to DAAs, and overall survival.

Does Schistosoma Mansoni Facilitate Carcinogenesis?

Schistosomiasis is one of the most prominent parasite-induced infectious diseases, causing tremendous medical and socioeconomic problems. Current studies have reported on the spread of endemic regions and the fear of development of resistance against praziquantel, the only effective drug available. Among the Schistosoma species, only S. haematobium is classified as a Group 1 carcinogen (definitely cancerogenic to humans), causing squamous cell carcinoma of the bladder, whereas infection with S. mansoni is included in Group 3 of carcinogenic hazards to humans by the International Agency for Research on Cancer (IARC), indicating insufficient evidence to determine its carcinogenicity. Nevertheless, although S. mansoni has not been discussed as an organic carcinogen, the multiplicity of case reports, together with recent data from animal models and cell culture experiments, suggests that this parasite can predispose patients to or promote hepatic and colorectal cancer. In this review, we discuss the current data, with a focus on new developments regarding the association of S. mansoni infection with human cancer and the recently discovered biomolecular mechanisms by which S. mansoni may predispose patients to cancer development and carcinogenesis.

Schistosomal liver fibrosis and hepatocellular carcinoma - case series of patients submitted to liver transplantation

Schistosomiasis affects approximately 207 million people in 76 countries. The association between hepatocellular carcinoma and Schistosoma mansoni infection has been investigated. Studies using animal models suggest that the parasite may accelerate the oncogenic process when combined with other factors, such as hepatitis C virus infection or exposure to a carcinogen. Herein, we report a case series of six hepatocellular carcinoma patients from Northeast Brazil, with negative serology for both hepatitis B and C virus, submitted to liver transplantation, whose explant showed evidence of schistosomal liver fibrosis. Since all patients enrolled in this study were submitted to liver transplantation, we were able to access the whole explanted liver and perform histopathological analysis, which is often not possible in other situations. Although 50% of them showed signs of liver failure, no cirrhosis or any liver disease other than schistosomal fibrosis had been detected. These uncommon findings suggest that Schistosoma mansoni infection might predispose to hepatocellular carcinoma development, regardless of the absence of other risk factors.

Epigastric Pain in a Patient with Cirrhosis

•Classic images of Schistosomiasis.•Pathology proved case.•Impressive educational case.