Cancer And Alcohol

What is cancer?

Cancer is a disease characterised by the uncontrollable multiplication and spread of bodily cells.  It begins in the cells that make up the human body. Normal human cells divide and proliferate (cell division) to generate new cells as the body requires them. However, in cancer, cells multiply in an uncontrolled manner.

When cells age or get damaged, they die and are replaced by new cells. Occasionally, this ordered process breaks down and aberrant or damaged cells proliferate and reproduce inappropriately. These cells are capable of forming tumours, which are tissue masses. 

Tumours can be malignant or benign. Benign tumours do not penetrate or spread to adjacent tissues and when removed, they often do not recur, unlike malignant tumors.

However, benign tumours can sometimes be enormous. For example, benign brain tumours, can cause severe symptoms or be life-threatening. Cancerous tumours can move to distant areas of the body and develop new tumours. Tumours can also invade surrounding tissues and this process is called metastasis. cancerous tumour is another name for malignant tumours. Blood malignancies, including leukemias, typically do not form solid tumours.

Evidence that alcohol is cancer risk factor 

There is broad scientific agreement that alcohol use can cause several forms of cancer.^1,2. According to existing  data, a person's chance of acquiring an alcohol-related cancer increases proportionately with his or her alcohol use, particularly if the alcohol consumption is chronic. 

Even individuals who consume no more than one alcoholic beverage per day and binge drinkers (those who consume four or more alcoholic beverages for women and five or more for males in a single session) have a moderately elevated risk of developing certain malignancies. ^3-7

Based on 2009 statistics, an estimated 3.5% of cancer fatalities (about 19,500 deaths) were associated with alcohol).⁸ There are clear correlations between alcohol use and the occurrence of the following forms of cancer: 

• Malignancies of the head and neck: Moderate to excessive alcohol use is associated  with increased risk of some cancers of the head and neck. Moderate drinkers have 1.8-fold greater risks of oral cavity (excluding the lips) and pharynx (throat) cancers; and 1.4-fold greater risks of larynx (voice box) cancers than nondrinkers. While heavy drinkers have a 5-fold greater risk of oral cavity and pharynx cancers and a 2.6-fold greater risks of larynx cancers.^4,9 Furthermore, the risk of these malignancies have significantly increased among those who consume mentioned amount of alcohol and also smoke. ¹⁰

• Alcohol use at any level is related with an increased risk of esophageal squamous cell carcinoma, a subtype of esophageal cancer. Compared to abstinence, the hazards vary from 1.3 times greater for light drinking to nearly 5 times higher for heavy drinking. ^4,9

In addition, alcohol consumption considerably increases the risk of esophageal squamous cell carcinoma in individuals with an inherited deficit of an alcohol-metabolising enzyme. ¹¹

• Two kinds of liver cancer (hepatocellular carcinoma and intrahepatic cholangiocarcinoma) are associated around a twofold increase in risk when heavy alcohol use is present .^4,9,12,13
• Alcohol use is consistently associated with an elevated risk of breast cancer, according to epidemiologic research. In comparison to nondrinkers, light drinkers had a slightly elevated (1.04-fold) chance of developing breast cancer, according to a meta-analysis of 118 separate studies. The increased risk is larger among moderate drinkers (1.23-fold) and strong drinkers (1.6-fold).^4,9,1 An examination of prospective data for 88,000 women participating in two US cohort studies found that light to moderate drinking was linked with a 1.13-fold higher risk of alcohol-related malignancies (mainly breast cancer) among women who have never smoked.⁵
• Moderate to severe alcohol usage is related with 1.2- to 1.5-fold higher risks of colon and rectum cancers compared to abstinence from alcohol.^4,9,1

Numerous studies have investigated the relationship between alcohol use and the risk of developing various malignancies. For malignancies of the ovary, prostate, stomach, uterus and bladder, there were no studies that could establish a link with alcohol consumption (or the data was equivocal). However, emerging data suggests that alcohol intake is linked to elevated risks of melanoma, prostate, and pancreatic cancers.^4,15

Additionally, alcohol ingestion may raise the occurance of second primary malignancies. For example, a meta-analysis of 19 studies revealed that among patients with cancer of the upper aerodigestive tract (UADT) which includes the oral cavity, pharynx, larynx, and oesophagus there was a 1.09-fold increased risk of a second primary UADT cancer for every 10 grammes of alcohol consumed per day before the first UADT cancer diagnosis.¹⁶ It  is less certain whether alcohol intake raises the incidence of second primary tumours at locations other than the breast.^17,18,19

Resveratrol, a secondary plant component found in red wine grapes and other plants, has been studied for a variety of purported health benefits, including cancer prevention. Researchers have discovered no link between moderate red wine drinking and the chance of acquiring prostate cancer or colorectal cancer.^20,21 However, any possible benefits of alcohol usage for lowering the risk of some malignancies are likely overshadowed by the negative effects of alcohol.

Alcohol affecting cancer risk 

Researchers have oberved  that alcohol may raise the risk of cancer in a number of ways:

• Metabolising ethanol in alcoholic beverages to acetaldehyde, which is a harmful molecule and a possible human cancer causing agent (carcinogen), as it may damage both DNA and proteins.
• Oxidation is the process of producing reactive oxygen species (chemically reactive molecules that contain oxygen), which may damage DNA, proteins, and lipids (fats) in the body.
• Reducing the body's capacity to metabolise and absorb a range of nutrients that may be linked to cancer risk, including vitamin A, vitamin B complex minerals such as folate, vitamin C, vitamin D, vitamin E, and carotenoids.
• Increasing blood levels of oestrogen, a sex hormone associated with breast cancer risk.

During fermentation and manufacturing, alcoholic drinks may also include a number of carcinogenic pollutants, such as nitrosamines, asbestos fibres, phenols, and hydrocarbons. The mechanisms by which alcohol use may reduce the risk of some malignancies are unknown and may be indirect.

Alcohol-related malignancies influenced by genes

Alcohol-related cancer risk is impacted by a person's genes, especially the genes that code for enzymes involved in metabolising alcohol.²² Alcohol dehydrogenase (ADH) enzme transforms ethanol to the carcinogenic metabolite acetaldehyde, mostly in the liver. Recent data reveals that acetaldehyde is also produced in the oral cavity and may be regulated by the oral flora.^23,24

Numerous people of East Asian ancestry possess a variant of the ADH gene that codes for a "superlative" form of the enzyme. This extremely active ADH enzyme accelerates the transformation of alcohol (ethanol) into acetaldehyde, a toxin. Those of Japanese heritage with this form of ADH are more likely to develop pancreatic cancer than those with the more prevalent form of ADH.²⁵

Aldehyde dehydrogenase 2 (ALDH2) is an enzyme that converts poisonous acetaldehyde into harmless compounds. Some individuals, particularly those of East Asian heritage, possess a variation of the ALDH2 gene that codes for a deficient enzyme. When alcohol is consumed by those who generate the faulty enzyme, acetaldehyde levels rise. The buildup of acetaldehyde produces such unpleasant symptoms including face flushing and heart palpitations that the majority of individuals who inherited the ALDH2 variation are unable to consume significant quantities of alcohol and hence have a low chance of getting alcohol-related malignancies. 

Nevertheless, some people with a faulty type of ALDH2 might develop tolerance to the unpleasant effects of acetaldehyde and consume substantial quantities of alcohol. 

Epidemiologic studies have demonstrated that these individuals had a greater risk of alcohol-related esophageal cancer and head-and-neck malignancies than those with the fully functioning enzyme who consume equivalent amounts of alcohol.²⁶ This elevated risk is exclusively reported in individuals who have the ALDH2 variation and consume alcohol; it is not detected in individuals who contain the variant but do not consume alcohol.

Concerned about your or a loved one's alcohol consumption?

Selecting your moment is crucial. Ensure you are both in a relaxed state of mind. This is not the appropriate topic for an argument. You must be willing and able to listen. The more you listen, the more comfortable someone will feel to open up. Prepare yourself with as much information as possible so you can offer guidance on how to obtain assistance if asked. 

Remember that while you can assist someone on their journey, they must also be motivated to change. It may not be as simple as expressing your concerns and having the individual alter their behaviour. Be patient. Alcohol is a sensitive topic, so approach it with sensitivity and empathy. Consider how you would feel if a friend or loved one brought up your drinking in conversation. Choose an area that is safe and comfortable for the dialogue, and use encouraging language.

Avoid criticism, expressing judgements and using labels such as "alcoholic". Try to ask open-ended questions, such as "I have observed X, Y, or Z, what do you think?" instead of "don't you believe you have a problem?" 

Multiple emotions, such as despair, social acceptance, and coping, might influence a person's complex relationship with alcohol. It is difficult for a person to recognise, confess, and accept that their drinking may be detrimental to their health and relationships. They might not wish to and might not be prepared. However, acceptance is a significant step on the path to change. Therefore, it is essential to exercise patience, keep talks open, and refrain from passing judgement.

Conclusion

Majority of research is focused on whether a person's cancer risk decreases after quitting alcohol, particularly on head and neck malignancies and esophageal cancer. According to these research, in general, cessation of alcohol drinking is not related with immediate decreases in cancer risk. Cancer risk declines over time, however it may take years for the risk to revert to that of abstainers. As with the majority of questions regarding an individual's cancer treatment, it is preferable for patients to consult with their health care provider before consuming alcohol during or immediately after chemotherapy. Your doctor will be able to provide precise guidance regarding whether alcohol consumption is safe during various cancer therapies.