Table 1.
Overview of the most relevant studies investigating potential associations between viruses and cancers of the digestive system.
| First Author | Year | Virus | Cancer Type | Sample Origin | Number of Samples | Observation | Ref. |
|---|---|---|---|---|---|---|---|
| Maden | 1992 | HPV | Oral | USA | 131 | HPV-6 is associated with oral cancer | [36] |
| Jalouli | 2012 | HPV, HSV, EBV | Oral | UK, Sweden, Sudan, Norway, USA, Yemen, India, Sri Lanka | 155 | Higher proportion of samples with HSV and EBV in industrialized countries | [37] |
| Bjørge | 1997 | HPV | Esophageal | Norway | 228 | Increased risk of developing cancer among HPV-16-seropositive subjects | [38] |
| Zhang | 2015 | HPV | Esophageal | China | 3044 | HPV-16 is a possible risk factor | [39] |
| Wang | 2010 | HPV | Esophageal | China, USA | 435 | HPV infection is common in esophageal carcinoma, independent of region and ethnic group of origin | [40] |
| Kirgan | 1990 | HPV | Colorectal | USA | 90 | Association between HPV and colon neoplasia | [41] |
| Lee | 2001 | HPV | Colorectal | Taiwan | 38 | HPV-18 is a possible risk factor | [42] |
| Alexandrou | 2014 | HPV | Anal | Greece | 11 | Lower incidence of HPV in anal cancer compared to other Western countries | [43] |
| Kabarriti | 2019 | HPV | Anal | USA | 5927 | HPV is a significant prognostic marker in anal cancer, especially for locally advanced disease | [44] |
| Muresu | 2020 | HPV | Anal | Italy | 30 | HPV is a possible risk factor | [45] |
| Awerkiew | 2003 | HPV, EBV | Esophageal | Germany | 37 | EBV, but not HPV, was detected in esophageal cancer samples | [46] |
| Martínez-López | 2014 | EBV | Gastric | Mexico | 297 | Possible role for EBV in gastric cancer and early precursor lesions. | [47] |
| Corallo | 2020 | EBV | Gastric | Italy | 175 | Patients with EBV-positive gastric cancer who did not receive ICI had a better response to first-line chemotherapy and better survival compared with EBV-negative patients | [48] |
| Li | 2004 | EBV | Hepatic | China | 141 | Presence of HBV infection in HCC tissues | [49] |
| Song | 2006 | EBV | Colorectal | China | 115 | Possible association of EBV with colorectal carcinoma | [50] |
| Fiorina | 2014 | HPV, EBV, JCV, BKV | Colorectal | Italy | 44 | No or weak association of HPV, EBV, JCV, and BKV with colorectal cancer | [51] |
| Laghi | 1999 | JCV | Colorectal | USA | 23 | JCV DNA may play a role in the chromosomal instability observed in colorectal carcinogenesis | [52] |
| Hori | 2005 | JCV | Colorectal | Japan | 64 | Possible role of JCV in colorectal carcinogenesis | [53] |
| Jung | 2008 | JCV | Colorectal | USA | 74 | JCV T-Antigen is expressed in the early stage of colorectal cancer | [54] |
| Tokita | 2002 | TTV | Hepatic | Japan | 237 | High TTV abundance is an independent risk factor | [55] |
| Iloeje | 2010 | HBV | Pancreatic | Taiwan | 22,471 | Chronic HBV infection may be associated with an increased risk of pancreatic cancer | [56] |
| Zhou | 2012 | HBV, HCV | Bile duct | Meta-analyses (13 case-control studies and 3 cohort studies) |
- | HBV and HCV are risk factors in bile duct cancer | [57] |
| Hassan | 2008 | HBV | Pancreatic | USA | 476 | Past exposure to HBV is a possible risk factor in pancreatic cancer | [58] |
| Su | 2020 | HBV | Colorectal | Taiwan | 69,478 | Chronic HBV infection is strongly associated with increased risk of developing colorectal cancer | [59] |
| Dimberg | 2013 | CMV | Colorectal | Sweden, Vietnam | 202 | CMV DNA rate was significantly higher in cancerous tissues compared to normal tissues | [60] |
| Chen | 2016 | CMV | Colorectal | Taiwan | 556 | More favorable disease-free survival rate in non-elderly patients with CMV-positive tumors, specifically in patients with stage III disease | [61] |
| Chen | 2015 | CMV | Colorectal | USA, France, Italy, Japan, China, Taiwan | 92 | Specific genetic CMV polymorphisms are associated with different clinical outcomes | [62] |
| Jin | 2019 | HIV | Anal | Australia | Not applicable | People living with HIV are at markedly higher risk of anal cancer | [63] |
| Colón-López | 2018 | HIV | Anal | USA | Not applicable | Anal cancer incidence is markedly elevated among people with HIV infection | [64] |
| Grew | 2015 | HIV | Anal | USA | Not applicable | HIV-positive patients had significantly worse overall and colostomy-free survival rates than HIV-negative patients | [65] |
Abbreviations: HPV: human papillomavirus; HSV: herpes simplex virus; EBV: Epstein–Barr virus; ICI: immune-checkpoint inhibitor; HCC: hepatocellular carcinoma; JCV: John Cunningham virus; BKV: BK virus; TTV: TT virus; HBV: hepatitis B virus; HCV: hepatitis C virus; CMV: cytomegalovirus; HIV: human immunodeficiency virus. Not applicable means that the study did not involve human specimens.