Table 1.
Demographic characteristics of all included studies.
| First Author; Pub. Year (Ref.) | Study design | Size | Country (Province/City) | Study period | Inclusion criteria | Exclusion criteria | Matched factors | Opium use definition | QS* |
|---|---|---|---|---|---|---|---|---|---|
| MacLennan, R.; 1977 [48] | Case-Control | 533 | Singapore (Singapore) | January 1972 to June 1973 | Cases: Provisional diagnosis of lung cancer Controls: Hospital inpatients |
Following disorders in controls: chronic bronchitis, emphysema, coy pulmonale, myocardial infarction, angina for investigation and cancers of the oral cavity, pharynx, larynx, esophagus, pancreas or bladder | Age; Sex; Dialect | Opium ever smoked | 5 |
| Sadeghi, A.; 1979 [43] | Case-Control | 198 | Iran (Shiraz) | 1969 to 1976 | Cases: Histopathologically confirmed diagnosis of bladder carcinoma and complete medical history Controls: Inpatients at Nemazee Hospital who had a diagnosis other than cancer, pulmonary disease, or a bladder condition with verified histories regarding opium addiction and cigarette smoking habits |
Incomplete histories regarding opium and/or cigarette smoking habits | Age; Sex | – | 7 |
| Fahmy, M. S.; 1983 [75] | Case-Control | 1381 | Iran (Fars) | January 1962 to December 1976 | Cases: Histopathologically confirmed diagnosis of oral cavity cancer and complete medical history Controls: - |
– | Age, Socioeconomic status | – | 6 |
| Toutounchi, M.; 2000 [13] | Case-control | 284 | Iran (Isfahan) | March 1994 to March 1999 | Cases: Histopathologically confirmed diagnosis of bladder cancer Controls: Hospital inpatients in Internal Medicine and Surgery wards except Urology ward; Residence in Isfahan; Ability to answer to interviewers |
Controls with history of cancer in other organs or genitourinary system problems | Age (±2 years); Sex | – | 7 |
| Mousavi, M. R.; 2003 [76] | Case-Control | 410 | Iran (Kerman) | September 1996 to September 2002 | Cases: Histopathologically confirmed diagnosis of laryngeal squamous cell carcinoma Controls: Patients admitted to otolaryngology department in the study period |
Other cancers of the head and neck | Age | DSM-IV criteria for opium dependency and opium consumption for at least 5 years | 7 |
| Aliasgari, M. A.; 2004 [42] | Case-Control | 160 | Iran (Tehran) | 1997 to 2000 | Cases: Histopathologically confirmed diagnosis of bladder cancer who had undergone surgery Controls: Histopathologically confirmed diagnosis of benign prostatic hyperplasia (BPH) who had undergone surgery |
Females | Age, Sex | – | 5 |
| Ketabchi, A.; 2005 [41] | Case-Control | 242 | Iran (Kerman) | 1999 to 2003 | Cases: Known cases of bladder cancer admitted to urology wards Controls: Tumor-free controls admitted to urology wards |
Addiction to other substances except for Opium and having contact with known bladder cancer risk factors (e.g. dye, rubber workers and cigarette smoking) | Age, Sex | Permanent abuse of Opium and its derivatives | 7 |
| Nourbakhsh, A.; 2006 [40] | Case-Control | 510 | Iran (Tehran) | 1990 to 2000 | Cases: Histopathologically confirmed diagnosis of bladder transitional cell carcinoma (TCC) by pathologic light microscopic examination of the tumor biopsies and having a complete medical record necessary for the study Controls: Admission to trauma ward of Sina Hospital during 1990–2000 without any history, signs or symptoms of urinary problems |
– | – | Opium smoking or indigestion in the crude form at least 3 times a week for 5 years or more | 7 |
| Nasrollahzadeh, D.; 2008 [31] | Case-Control | 871 | Iran (eastern Golestan) | December 2003 to June 2007 | Cases: Histopathologically confirmed diagnosis of esophageal squamous cell carcinoma (ESCC), being agreed to participate in the study, aged over 18 years old, residing in the study area at the time of registration, and having no history of concurrent cancer in other organs or history of previous cancer in any organ Controls: Population based controls |
– | Age (±2 years); Sex; Neighbourhood of residence or village | Opium consumption at least once per week for a minimum of 6 months | 6 |
| Hosseini, S. Y; 2010 [39] | Case-Control | 358 | Iran (Tehran) | March 2004 to March 2008 | Cases: Histopathologically confirmed diagnosis of bladder in the urology department Controls: Genetically unrelated healthy subjects without a history of cancer |
Previous history of cancer; Metastasized cancer; Previous radiotherapy or chemotherapy, and occupational risk for BC Axis I psychiatric diagnosis, [(DSM)-IV] other than opiate, or caffeine dependence; and use of methadone, levomethadyl acetate, or naltrexone within the 14 days before enrollment. | Age (±5 years); Sex; Geographic origin, Ethnicity; Smoking history | DSM-IV criteria for opium dependency and opium consumption for at least 5 years | 6 |
| Shakhssalim, N.; 2010 [38] | Case-Control | 1384 | Iran (Tehran, Khorasan, Khuzestan, Isfahan and East Azerbaijan) | 2006 | Cases: Randomly selected newly registered bladder cancer cases at 2006 from regions predicted to have higher incidences Controls: Healthy controls |
– | Age (±5 years); Sex; Neighborhood of residence | Previous history of opium consumption | 5 |
| Masjedi, M. R.; 2013 [47] | Case-Control | 726 | Iran (Tehran) | October 2002 to October 2005 | Cases: Histopathologically confirmed diagnosis of lung cancer; No suspicion of pulmonary metastases from a different primary tumor; Agreed to undergo a 1•5-hour interview Controls: Inpatients in the same hospital and healthy individuals referred to visit their patients |
Control group with neoplasms and respiratory diseases | Age (±3 years); Sex; Place of residence | Consumption of Opium at least once a day for a minimum of 6 months | 7 |
| Shakeri, R.; 2013 [25] | Case-Control | 922 | Iran (Gonbad) | December 2004 to December 2011 | Cases: Histopathologically confirmed diagnosis of stomach adenocarcinoma Controls: Healthy individuals selected from Golestan Cohort Study |
– | Age; Sex; Place of residence | Opium consumption from more than a year before diagnosis | 7 |
| Shokri-Shirvani J.; 2013 [77] | Cross-sectional | 961 | Iran (Babol) | March 2005 to March 2011 | Cases: Endoscopic diagnosis of stomach cancer Controls: All patients who were examined by endoscopy and were not diagnosed as having cancer |
History of gastric and esophageal cancer surgery, vagotomy, and gastrojejunostomy; Patients visited for cancer work up | – | Opium consumption for at least 1 year and 3 times a week | 7 |
| Hakami, R.; 2014 [28] | Case-Control | 120 | Iran (Gonbad, Shiraz) | December 2004 to December 2011 | Cases: Histopathologically confirmed diagnosis of esophageal squamous cell tumors; Being able to answer the questions; Diagnosed within 6 months prior to the interviews Controls: Controls were recruited from Golestan and Fars provinces (High-risk and low-risk regions, respectively) and they were without any evidence of upper gastrointestinal tract malignancy on endoscopy and they had no family history of esophageal cancer in first-degree relatives |
Subjects who had Changed their dietary habits over the past year because of disease or any other reasons | Age (±5 years); Sex | Opium ever used | 6 |
| Naghibzadeh Tahami, A.; 2014 [59] | Case-Control | 426 | Iran (Kerman) | August 2010 to November 2012 | Cases: Histopathologically confirmed diagnosis of Upper gastrointestinal (oral cavity, liver, esophagus, stomach, or pancreas) cancers were selected from the northern part of Kerman Controls: Neighborhood controls |
Dissatisfaction to participate in the study | Age; Sex; Place of residence | Opium ever used | 7 |
| " | " | " | " | " | Cases: Histopathologically confirmed diagnosis of stomach cancers were selected from the northern part of Kerman Controls: Neighborhood controls |
" | " | " | " |
| Razmpa, E.; 2014 [9] | Case-Control | 160 | Iran (Tehran) | October 2008 to September 2010 | Cases: Histopathologically confirmed diagnosis of oral cavity squamous cell carcinoma among 80 consecutive patients who were referred to the ear-nose-throat department Controls: Normal controls |
– | Age; Sex; Socioeconomic status | Opium addiction for at least 5 years | 7 |
| Sadjadi, A.; 2014 [26] | Cohort | 928 | Iran (Ardabil) | (A 10-year study) | Cases: Histopathologically confirmed diagnosis of stomach cancer; Age over 40 years' old Controls: - |
Participant's refusal; Subject's known gastrointestinal, cardiac or respiratory disease, and pregnancy | – | Opium use for at least once a week for the last 6 months | 6 |
| Akbari, M.; 2015 [37] | Case-Control | 594 | Iran (Shiraz) | 2012 to 2013 | Cases: Histopathologically confirmed bladder of stomach cancer Controls: Neighborhood controls |
– | Age; Sex; Place of residence | Opium ever used | 6 |
| Aliramaji, A.; 2015 [36] | Case-Control | 350 | Iran (Babol) | 2001 to 2012 | Cases: Histopathologically confirmed diagnosis of bladder cancer who underwent a surgical operation during the study period Controls: Hospital patients referred for assessment of gall bladder stones |
Incomplete data | Age; Sex | Opium ever used | 7 |
| Ghadimi, T.; 2015 [35] | Case-Control | 304 | Iran (Kurdistan) | 2012 to 2015 | Cases: Histopathologically confirmed diagnosis of bladder cancer Controls: Registered patients who referred to the same Clinic/Hospital |
For cases: Death and suffering from other cancers; For controls: Having cancer. | Age (±5 years); Sex; Place of residence | – | 7 |
| Dianatinasab, M.; 2016 [33] | Cohort | 220 | Iran (Shiraz) | 2009 to 2014 | Cases: Diagnosis of colorectal cancer; Having undergone surgery; Not having other cancers in other parts of the body Controls: - |
Incomplete data | – | – | 6 |
| Lotfi, M. H.; 2016 [78] | Case-Control | 400 | Iran (Yazd) | 2009 to 2013 | Cases: Histopathologically confirmed diagnosis of bladder cancer Controls: - |
– | Age (±2 years); Sex; Place of residence | Opium ever used | 8 |
| Naghibzadeh Tahami, A.; 2016 [32] | Case-Control | 525 | Iran (Kerman) | January 2012 to December 2014 | Cases: Histopathologically and clinically confirmed diagnosis of colorectal cancer Controls: - |
– | Age; Sex; Place of residence | Opium ever used | 7 |
| " | " | 426 | " | " | Cases: Histopathologically and clinically confirmed diagnosis of colon cancer Controls: - |
" | " | " | " |
| Shakeri, R.; 2016 [45] | Case-Control | 685 | Iran (Tehran) | January 2011 to January 2015 | Cases: Histopathologically confirmed diagnosis of pancreatic adenocarcinoma Controls: Normal pancreas in the EUS exam; age 40 years or older; a final diagnosis of either asymptomatic small (<10 mm) submucosal lesion in the esophagus or stomach, or a gallbladder or common bile duct stones without cholangitis; no history or current diagnosis of liver failure or renal failure; no history of cancer; no adherence to special diets; no diagnosis of opium-induced common bile duct dilatation or sphincter of Oddi dysfunction; and no development of pancreatic disease or any cancers 1 year after the initial visit. |
Not matching with the inclusion criteria | – | Opium use at least weekly for a period of 6 months or more | 7 |
| Bakhshaee, M.; 2017 [12] | Case-Control | 85 | Iran (Mashhad) | September 2008 to August 2010 | Cases: Histopathologically confirmed diagnosis of laryngeal cancer Controls: Healthy individuals with no evidence of head and neck or esophageal malignancies |
– | Age | Opium consumption at least once a day for a minimum of one year | 7 |
| " | " | 125 | " | " | Cases: Histopathologically confirmed diagnosis of esophageal squamous cell carcinoma Controls: Healthy individuals with no evidence of head and neck or esophageal malignancies |
" | " | " | " |
| Lankarani, K. B.; 2017 [19] | Case-Control | 480 | Iran (Shiraz) | January 2014 to December 2015 | Cases: New histopathologically confirmed Colorectal cancer cases whom registered in the cancer registry system | – | Age (±5 years); Sex; Place of residence | Opium ever used | 7 |
| Berjis, N.; 2018 [57] | Case-Control | 360 | Iran (Isfahan) | 2014 to 2015 | Cases: Histopathologically confirmed diagnosis of laryngeal squamous cell carcinoma (SCC); Availability of information in patients' records; Possibility of contact with the patient or his family to complete data; Lack of family history of cancer and squamous cell carcinoma of head and neck and other masses except the squamous cell cancer of the larynx Controls: Healthy controls with no laryngeal cancer who were referred to the hospitals which were under investigation |
Incomplete data | – | – | 5 |
| Pournaghi, S. J.; 2019 [27] | Case-Control | 283 | Iran (North Khorasan) | 2013 to 2015 | Cases: Histopathologically confirmed diagnosis of esophageal squamous cell carcinoma (SCC); Age above 18 years; Residence in North Khorasan province; No history of cancer in other organs Controls: Randomly selected hospital inpatients of 2 general hospitals |
Inability to answer interviewer's questions; Not consenting to participate in the study | Age; Sex | Opium ever used | 6 |
| Vazirinejad, R.; 2020 [58] | Case-Control | 285 | Iran (Rafsanjan) | 2018 | Cases: Histopathologically confirmed diagnosis of gastrointestinal cancer in the previous two years Controls: A half of healthy controls were cases' relatives and the others were their neighbors |
Non-Iranian people; Consumption of alcohol, nas, and other opioid drugs such as heroin, methadone, and morphine; History of or concurrent cancers | Age; Sex; Place of residence; Smoking | History of opium use more than a year | 9 |
| Alizadeh, H.; 2020 [79] | Case-control | 420 | Iran (Kerman) | January 2014 to December 2017 | Cases: Histopathologically confirmed diagnosis of head and neck cancers | – | Age (±5 years); Sex; Place of residence | Opium ever used | 6 |
| " | " | " | " | " | Cases: Histopathologically confirmed diagnosis of laryngeal cancer | " | " | " | " |
| Naghibzadeh Tahami, A.; 2020 [80] | Case-control | 420 | Iran (Kerman) | January 2014 to December 2017 | Cases: Histopathologically confirmed diagnosis of lung cancer | – | Age (±5 years); Sex; Place of residence | Opium ever used | 6 |
| Sheikh, M.; 2020 [55] | Cohort | 50,034 | Iran (eastern Golestan) | January2004 to June 2008 | Rural and Urban residents of Golestan Province aged 40–75 years | Previous diagnosis of upper gastrointestinal cancer; Not consent to participate in the study; Temporary residency in the study area | – | Opium ever used | 9 |
| Mohebbi, M.; 2020 [81] | Case-control | 3698 | Iran (10 provinces) | April 2016 to April 2019 | Cases: Incident histopathologically confirmed diagnosis of head and neck squamous cell carcinomas Controls: Hospital visitors who visited the hospital for any reason other than receiving treatment |
Emergency and maternity wards were excluded for control recruitment | Age; Sex; Place of residence | Opium consumption at least once a week for at least a six-month consecutive period throughout their life | 8 |
⁎
QS: Quality Score from 9.