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An Overview of Colorectal Cancer 

With about 1500 newly diagnosed cases of Colorectal cancer in Singapore each year, the risk of a person getting colorectal cancer during his lifetime is 5.6%. Colorectal cancer comes out to be the most common cancer when considering both the male and female populations in Singapore. It is also the second leading cause of death in the USA.

What is Colorectal Cancer?

The term Colorectal Cancer refers to the cancer of parts of the large gut. i.e., either the colon or rectum. The colon and rectum make up the majority of the large gut. This cancer is most often characterized by the uncontrolled growth of the cells of the large gut lining known as epithelial cells.

Colorectal cancer is strongly linked to family history as well as other gastrointestinal disorders of the large gut such as colonic polyps. Polyps are the outgrowth in the inner lining of the large gut. In fact, most colorectal cancers start as polyps which then acquire the ability to divide indefinitely.

Colorectal cancer may grow outward into the wall of the gut and involve the outer layers from which it can spread to blood vessels or lymph nodes and ultimately to the other parts of the body.

What are the Signs and Symptoms of Colorectal Cancer?

Colorectal cancer in its early stages may be undetected due to being silent (having no symptoms at all) although there are certain alarming signs of colorectal cancer. These include;

● Change in Bowel habits – Colorectal cancer might manifest as diarrhoea or constipation.
● Unexplained Anaemia – When detected on routine investigation might warrant screening for colorectal cancer.
● Blood in stools – Most often presenting as fresh blood mixed with stools.
● Anorexia and weight loss.
● Abdominal Mass – Manifesting as abdominal fullness and other mass effects.
● Abdominal Pain – Most often in the lower abdomen.

Clinically your physician may feel a mass on examination. The diagnosis of colorectal cancer is usually made after a colonoscopy either as a part of screening or on the doctor’s advice. A biopsy Is usually taken during colonoscopy for histopathological testing. A CT scan as well as a barium enema might be done to demarcate the extent of the spread of colorectal cancer.

What are the Risk Factors and Causes of Colorectal Cancer?

The risk factors of colorectal cancer include;

• Smoking.
• Having inflammatory bowel disease (IBD).
• Being obese or overweight (Obesity is especially linked to colorectal cancer in men).
• A diet containing a greater amount of red meat or processed meat.
• Having low levels of Vitamin D.
• Sedentary lifestyle (limited physical activity).
• Alcohol consumption.
• Being older than 50.
• Family history of colorectal cancer or having adenomatous polyp of the colon.
• Having type 2 diabetes.

The causes of colorectal cancer are a bit unclear. It is shown to develop from a number of environmental as well as genetic factors.

According to the American Cancer Society (ACS), about 15% of colorectal cancers have been shown to have a strong genetic root. Some inherited genetic syndromes that predispose to colorectal cancer are;

• Familial Adenomatous Polyposis (FAP).
• Hereditary non-Polyposis colorectal cancer (HNPCC).
• Peutz-Jeghers Syndrome.
• MUTYH-associated polyposis (MAP).

Colorectal cancer may result from acquired genetic mutations as well. These involve DNA damage to the patient throughout his/her life. Certain risk factors play a role in these acquired mutations but the exact causes have not been determined yet.

How to prevent Colorectal Cancer?

Some of the preventive measures against the development of colorectal cancer are;

• Screening for colorectal cancer – Regular screening can decrease the risk of the development of colorectal cancer. Polyps if found can be removed if indicated to prevent their transformation into malignant masses. Patients should have a colonoscopy every 10 years starting at the age of 50 years as routine screening. Those having a familial history of colorectal cancer or polyposis may start screening 10 years earlier than the age at which their family member developed the disease or the age of 40 years, whichever comes earlier.
• Dietary measures – Diets having a high content of fruits, vegetables, and whole grains are linked with prevention against the development of colorectal cancer.
• Regular physical activity – Increased physical activity has been linked to a lower risk of colorectal cancer and polyps while limiting the sitting time as well as time lying down also helps in prevention.
• Limiting alcohol intake – Several studies have found an increased incidence of colorectal cancer with increased alcohol intake.
• Maintain Bodyweight at healthy levels.
• Cessation of smoking.
• Taking multivitamins – Some studies suggest a reduced incidence of colorectal cancer with regular intake of multivitamins, calcium and magnesium.

References

1) https://www.medicalnewstoday.com/articles/155598#causes-and-risk-factors
2) https://www.nuh.com.sg/Health-Information/Diseases-Conditions/Pages/Colorectal-Cancer.aspx#:~:text=In%20Singapore%2C%20the%20risk%20of,there%20is%20chance%20for%20cure.
3) https://www.cancer.org/cancer/colon-rectal-cancer/causes-risks-prevention.html

How to increase Testosterone levels naturally – Testosterone Deficiency in Men

According to a study by the European Association of Urology, there is a 20% prevalence of testosterone deficiency in adolescents and young males. Another study published in the Journal of Clinical Endocrinology and Metabolism demonstrated the generational decline in testosterone levels in males. According to this, there was about a 0.4% cross-sectional decline per year of age. A more recent study revealed “a highly significant age-independent decline in total testosterone in the first and second decades of the 21^st century. The decline was unlikely to be explained by increasing rates of obesity.”. In short, there is a great amount of research work indicating declining testosterone levels in men across various cultures.

What is Testosterone deficiency?

The inability of the body to produce enough testosterone is called testosterone deficiency. The production of testosterone is controlled by the testes as well as a part of the brain called the hypothalamus. Its production increases during puberty and is responsible for maintaining physiological and sexual well-being in men.

Broadly speaking, an individual having a blood serum testosterone level of less than 300ng/dL is said to be testosterone deficient. Although this is highly variable across different age groups and individuals, since a person having testosterone levels greater than the said threshold may still be testosterone deficient because of high SHBG (Sex hormone-binding globulin), a protein which binds free testosterone in the blood. This results in decreased levels of readily available testosterone.

Similarly, adolescents and young males have a higher testosterone requirement for their physiological well-being. In addition, the sensitivity for testosterone receptors varies across individuals resulting in a slightly variable potency of the effect of testosterone.

What are the Signs and Symptoms of Testosterone deficiency?

Testosterone deficiency has several health implications, some of which are;

• Loss of libido (decreased sex drive).
• Loss of lean muscle mass.
• Tiredness and Chronic fatigue.
• Difficulty losing weight (increased body fat content).
• Erectile dysfunction.
• Lack of motivation and symptoms of depression.
• Decreased bone density leading to easy fractures.
• As testosterone is essential for the adequate development of male gonads which in turn leads to further deficiency in testosterone production.
• Decreased sperm count and fertility.
• Difficulty concentrating.
• Delayed puberty.
• Lack of deepening of the voice.

What are the Causes of Testosterone deficiency?

Although a decrease in the level of testosterone is a normal part of the ageing process, it is influenced by several environmental factors as well as lifestyle choices. Some of the most important causes of lower testosterone levels include;

• Obesity – Increased fat tissue in the body leads to increased aromatisation of testosterone which is a process that converts testosterone into oestrogen.
• Environmental oestrogen mimicking molecules – Found in plastics and certain plant sources as well. These are classified as phytoestrogens and xenoestrogens.
• Alcohol and drug abuse – Increase the levels of the female sex hormone estrogenic as well as the stress hormone cortisol.
• Chronic stress – Increases the levels of cortisol which mostly counteracts the effects of testosterone.
• Testicular injury or infection.
• Varicocele.
• Genetic conditions – Such as Klinefelter’s Syndrome can lead to lower testosterone levels as well.
• Hormonal disorders – Pituitary gland disease or other hormonal disorders affecting the pituitary-gonadal hormone axis.
• Lack of competition and a sedentary lifestyle – Also shown to be responsible for a significant decrease in testosterone levels.
• Poor sleep hygiene.
• Insulin resistance and diabetes – Also negatively impact testosterone levels.

How to increase testosterone levels naturally?

The best natural preventions against testosterone deficiency are;

• Regular physical exercise – Studies show higher levels of testosterone achieved through exercises especially resistance training and heavy lifting. High-intensity interval training (HIIT) is also helpful in optimizing testosterone levels. At the same time, physical exercise can also impact levels of testosterone negatively as well if it is excessive or increases overall stress levels (higher cortisol).
• Optimizing diet – A diet containing higher levels of fats, and fat-soluble vitamins especially vitamin D is highly effective in regulating testosterone levels. Similarly, certain minerals like zinc and magnesium are also highly effective. This involves a higher intake of red meats, fish, and oysters.
• Taking plenty of sunlight – Studies have shown the positive impact of sunlight on vitamin D levels as well as a person’s overall mood. Both of which impact testosterone levels positively.
• Take up sports – Competition has also been linked to higher levels of testosterone levels.
• Adequate Sleep – Regular uninterrupted night’s sleep of at least 6 hours or more is also highly important and not stressed enough. It is important to note that regularity and quality of sleep is the most important aspect of sleep hygiene.
• Address any medical conditions – Contact your doctor to optimally deal with medical issues resulting in testosterone deficiency.

References

• https://www.healio.com/news/endocrinology/20120325/generational-decline-in-testosterone-levels-observed#:~:text=The%20estimated%20cross%2Dsectional%20decline,1.4%25%20to%20%E2%80%931.0%25).
• Lokeshwar, S. D., Patel, P., Fantus, R. J., Halpern, J., Chang, C., Kargi, A. Y., & Ramasamy, R. (2021). Decline in Serum Testosterone Levels Among Adolescent and Young Adult Men in the USA. European urology focus, 7(4), 886–889. https://doi.org/10.1016/j.euf.2020.02.006
• https://www.wolterskluwer.com/en/news/standard-threshold-for-low-testosterone-doesnt-apply-to-young-men#:~:text=The%20standard%20cutoff%20point%20for%20low%20testosterone%20is%20300%20nanograms,related%20decline%20in%20testosterone%20levels.
• https://www.webmd.com/men/ss/slideshow-low-testosterone-natural-boost
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5031462/
• Kotta, S., Ansari, S. H., & Ali, J. (2013). Exploring scientifically proven herbal aphrodisiacs. Pharmacognosy reviews, 7(13), 1–10. https://doi.org/10.4103/0973-7847.112832
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063751/
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7739287/

Does Chronic Obstructive Pulmonary Disease (COPD) lead to Lung Cancer? 

The development of Chronic Obstructive Pulmonary Disease (COPD) as well as Lung Cancer is primarily influenced by smoking. For us to make a distinction between the two as well as to understand how these are related to one another, we need to define COPD.

What is COPD?

COPD is a condition in which the damage to lung tissue reduces the elastic recoil of the lungs, causing shortness of breath. COPD occurs in the setting of emphysema and chronic bronchitis. Long-term exposure to airborne irritants like cigarette smoke and air pollutants leads to lung damage (Emphysema) and the superadded infections result in further lung damage and morbidity (Chronic Bronchitis). As a result, the airways and air sacs of the lungs lose their elasticity (ability to expand and shrink back), the walls of the air sacs may get thickened and the airways may produce more mucus than normal which can clog the airways and thus ‘obstruct’ the passage of air. Almost all cases of COPD are caused by tobacco smoking.

Is COPD related to the development of Lung Cancer?

COPD is indirectly related to the development of Lung Cancer in the sense that the precursors for the development of both conditions are primarily cigarette smoke and airborne irritants. Patients with COPD are at a higher risk of developing Lung cancer than those who don’t have COPD. COPD directly sets the stage for the development of lung cancer by damaging the cells of the lungs and placing greater stress on the repair mechanisms often to the point of exhaustion. This can lead to damage to the DNA of the cells. Such damaged cells may divide indefinitely and result in the development of lung cancer (Uncontrolled division of cells).

COPD is caused by a variety of environmental and genetic factors. According to an article published in BioMed research international 2019, Cigarette smoke increases capillary fluid leakage and inflammation in lung tissue. This leads to increased EMT (Epithelial-Mesenchymal Transition) and EndMT (Endothelial-Mesenchymal Transition) which increases the risk for tumorigenesis (development of cancer). The direct cell damage and repair in the setting of chronic inflammation also increases the risk of the development of lung cancer.

According to a pooled global study conducted at Harvard T.H. Chan School of Public Health; “Compared with non-COPD subjects, smoking behaviours showed a significantly higher effect on SCLC risk among COPD subjects, and further, COPD patients showed a 1.86-fold higher risk of SCLC.” Thus, COPD shows a direct causal pathway for the development of Small Cell Lung Carcinoma and warrants further research on the given topic.

The Difference between the Symptoms of COPD and Lung Cancer

While many of the symptoms of both COPD and Lung Cancer are similar such as shortness of breath, coughing, wheezing and chest tightness, there are certain key alarm features that clinically distinguish Lung Cancer from COPD. These are;

● Anorexia and cachexia (extreme weight loss and wasting of body). This weight loss is unexplained having no fathomable cause.
● Coughing up blood (Hemoptysis)
● Tiredness and Chronic fatigue
● Chest pain
● Loss of appetite
● Hoarseness of voice
● A chronic cough that gets worse and does not go away

Preventive Measures for COPD

The best preventions against COPD are;
● Cessation of smoking or should not start smoking in the first place.
● Reduction of exposure to airborne noxious stimuli. This may be done in a variety of ways like wearing face masks. etc.
● Reducing the exposure to Second-Hand Smoke (smoke from the burning end of a cigarette or the smoke inhaled from the smoking by another person).
● Getting counselling or joining support groups to help quit smoking. Using products that help wean you off smoking.
● Pulmonary rehabilitation.
● Maintaining a healthy lifestyle and having an exercise routine. A study in the American Journal of Respiratory and Critical Care Medicine indicated that physical exercise protects against the development of COPD as well as its progression.
● Early detection of COPD by chest X-ray (hyperinflated lungs, tubular heart and decreased vascular markings) and PFT (Pulmonary Function Testing).
● Breathing Exercises and Chest Physiotherapy.
● Taking occupational precautions in case of high exposure to smoke.
● Coordinated community research and awareness for better management of COPD and Lung Cancer at the level of the community.
● Annual flu vaccination and pneumococcal vaccination to help prevent respiratory infections and chronic bronchitis.

In short, COPD is one of the most prevalent respiratory illnesses (2.3% of the Singaporean population has COPD) and awareness and appropriate prevention can reduce significant morbidity and mortality thus improving quality of life.

References

1) https://www.sciencedirect.com/science/article/pii/S235239641530147X
2) Hou, W., Hu, S., Li, C., Ma, H., Wang, Q., Meng, G., Guo, T., & Zhang, J. (2019). Cigarette Smoke Induced Lung Barrier Dysfunction, EMT, and Tissue Remodeling: A Possible Link between COPD and Lung Cancer. BioMed research international, 2019, 2025636. https://doi.org/10.1155/2019/2025636
3) https://www.cdc.gov/cancer/lung/basic_info/symptoms.htm
4) Garcia-Aymerich, J., Lange, P., Benet, M., Schnohr, P., & Antó, J. M. (2007). Regular physical activity modifies smoking-related lung function decline and reduces risk of chronic obstructive pulmonary disease: a population-based cohort study. American journal of respiratory and critical care medicine, 175(5), 458–463. https://doi.org/10.1164/rccm.200607-896OC

Health Connect – March 2023

Anaemia happens when one has insufficient red blood cells and/or has red blood cells that are not functioning properly. It is characterized by low haemoglobin levels. This is important because red blood cells and haemoglobin assist in transporting oxygen around the body to allow the tissues to function properly.