Oesophageal cancer studies in the caspian littoral of Iran: Some residual results, including opium use as a risk factor

Abstract

A study was conducted in northern Iran in areas of very high, high and moderately low incidence of oesophageal cancer. Morphine metabolites in urine as an indicator of opium use, and a variety of nutritional and biochemical measures, including salivary antipyrine half-life, were determined in households with a case of oesophageal cancer and in control households. Results on 1,590 individuals showed that the prevalence of appreciable levels (greater than or equal to 1 microgram/ml) of urinary morphine metabolites was much higher in areas of high and very high incidence of oesophageal cancer than in low-incidence areas, particularly for those under age 50 years in both sexes, where a 6-fold difference was seen. Members of households with a case of oesophageal cancer had a higher prevalence of positive urinary morphine metabolite findings than members of control households from the same village. Salivary anti-pyrine half-life (AP-T1/2), as a measure of hepatic drug metabolizing capacity, was estimated in 120 subjects. No relationship was seen with use of opium, region of residence, case-control status of household, age or sex. Experimental studies have meanwhile identified mutagenic substances with carcinogenic potential in opium pipe scrapings, used widely in the study region, opium pyrolysates and morphine pyrolysates. Our data give additional support to the hypothesis that opium use, in the form of its pyrolysates, is one of the factors involved in the aetiology of oesophageal cancer in the region.

Opium, tobacco, and alcohol use in relation to oesophageal squamous cell carcinoma in a high-risk area of Iran

“…Factors contributing to this decline may include improved socioeconomic status, more widespread access to piped water, and more fresh fruits and vegetable use due to greater availability of refrigerators. Also, the prevalence of opium use in our study was approximately half of that reported in the 1970s (Ghadirian et al, 1985), when sukhteh use was common (Hewer et al, 1978), but not reported by our subjects.…”

“…An ecologic study in northern Iran found that 50% (20 out of 40) of adults in ESCC high-risk areas, compared with only 11% (10 out of 90) of those in medium-or low-risk areas, tested positive for urine morphine metabolites (Joint Iran-IARC Study Group, 1977). In a subsequent study of 1590 rural individuals, the prevalence of appreciable levels (X1 mg ml À1 ) of urinary morphine metabolites was almost six-fold higher among residents of high-risk vs low-risk areas (Ghadirian et al, 1985). Among the spouses of 41 cases and 41 age-matched controls, there was a two-fold, nonsignificant, increased risk associated with the presence of urinary morphine metabolites.…”

“…Previous studies in Iran (Cook-Mozaffari et al, 1979;Ghadirian et al, 1985) avoided using questionnaires to ask about opium use, partly because it can be a sensitive subject in many populations, which may limit the validity of questionnaire responses. This was tested during the pilot phase of an ongoing cohort study in Golestan by interviewing subjects twice and collecting urine samples twice, 2 months apart .…”

“…Studies conducted by the International Agency for Research on Cancer (IARC) and Institute of Public Health Research (IPHR) of the University of Tehran in the 1970s suggested that opium consumption was one causal factor (Cook-Mozaffari et al, 1979). Two studies found an almost six-fold higher prevalence of appreciable levels (X1 mg ml À1 ) of urinary morphine among residents of the high-risk areas than in lower risk areas (Joint Iran -IARC Study Group, 1977;Ghadirian et al, 1985). One of these studies prematurely terminated in 1979, found a twofold increased positivity rate for urinary opium metabolites among spouses of 41 case subjects compared with matched controls (Ghadirian et al, 1985).…”

“…Two studies found an almost six-fold higher prevalence of appreciable levels (X1 mg ml À1 ) of urinary morphine among residents of the high-risk areas than in lower risk areas (Joint Iran -IARC Study Group, 1977;Ghadirian et al, 1985). One of these studies prematurely terminated in 1979, found a twofold increased positivity rate for urinary opium metabolites among spouses of 41 case subjects compared with matched controls (Ghadirian et al, 1985). Opium use is still prevalent in Golestan Province, especially among rural men , and may contribute to the high rates of ESCC in this area.…”