ROLE OF NUTRITION IN CANCER PREVENTION

Around in 1980 prominent epidemiologists estimated that about 30% of all cancer cases are attributable to dietary habits. More than 25 years later American Institute of Cancer Research came to the similar conclusion.

About one third of the most common cancers in higher income countries and about one fourth in lower income countries could be prevented through eating healthily, being physically active, and maintaining a healthy weight.

BODY FATNESS

Overweight is one of the most important risk factors for cancer: it convincingly increases the risk of colonic cancer, breast cancer, endometrial, oesophageal, pancreatic and kidney cancers.

It is not simply overweight, but the distribution of fat mass which appears to influence the risk.

Abdominal fat and possibly visceral fat is convincingly associated with a 70% increase in risk of colon cancer and probably increases the risk of postmenopausal breast cancer, pancreatic cancer, and endometrial cancer.

The risk of cancer attributable to excess body mass index (BMI).

AICR advises to be as lean as possible within the normal range of body weight.

A healthy weight is best achieved by choosing diets based on foods with low energy density, avoiding sugary drinks, and being physically active throughout life.

PHYSICAL ACTIVITY

Independently of the effect on body fatness, physical activity convincingly decreases the risk of colon cancer, probably protects against post menopausal breast cancer and endometrial cancer.

Being moderately physically active means 30 minutes of active walking, biking, and/or gardening per day. When overweight is already present, 60 minutes physical activity is advised.

PLANT FOODS

Most diets that are protective in nature are from plant origin. Consumption of non-starchy vegetables protects against cancers of mouth, pharynx, larynx, oesophagus and stomach.

Allium vegetables probably protect against stomach cancer. Garlic probably protects against cancers of colon and rectum.

Fruits decreases the risk of mouth, pharynx, larynx, oesophagus lung and stomach cancers.

The beneficial effects of vegetables and fruits could be due to dietary fibre, specific vitamins or other bioactive compounds.

AICR recommends to eat at least five portions (400 gms) of a variety of vegetables and of fruits per day, and to consume unrefined grains and pulses at each meal.

RED MEAT AND PROCESSED MEATS

Consumption of red meat (beef, pork, lamb, horse) and processed meat (red meat preserved by smoking, curing, salting and by adding preservatives, such as ham, bacon, salami, sausages, etc.) convincingly increases the risk of colorectal cancer.

Increasing the consumption of red meat by one intake per week increases the risk of colorectal cancer by about 40%, for processed meat the risk of colorectal cancer increases by about 20% with each 50gm per day.

It is the heam iron content of red meat, which irritates the colonic mucosa may lead to carcinogenesis. Other compounds responsible are heterocyclic amines, N–nitroso compounds and polycyclic aromatic hydrocarbons.

AICR recommends to limit the consumption of red meat to 500 gms per week.

ALCOHOL

Alcoholic drinks are a cause of several cancers, i.e. cancer of oral cavity, breast, colorectal cancers in men is convincing. In western Europe 10% of cancers in men and 3% of cancers in female are estimated to be attributable to alcohol consumption.

However the modest amount of alcoholic drinks are likely to protect against coronary heart diseases, the AICR recommends one drink for female, two drinks for men per day when alcohol is consumed.

PRESERVATION, PROCESSING, AND PREPARATION OF FOOD

Some methods of food preservation, processing and preparation affect cancer risk. Salt and salt preserved foods are probably a cause of stomach cancers.

Foods contaminated with aflatoxins, such as cereals and pulses are a cause of liver cancer. Aflatoxins are produced by moulds when foods are stored too long at warm temperatures.

AICR recommends to avoid salt preserved, salted or salty foods to ensure an intake of less than 6 gm (2.4gms sodium) a day.

CONCLUSIONS

The main risk factors for cancer associated with food, nutrition, and physical activity are known and recommendations to decrease ones risk of cancer are available.

UTERINE TUMORS (FIBROIDS)

Uterine fibroids are noncancerous growths of the uterus that often appear during childbearing years. Also called leiomyomas or myomas, uterine fibroids aren't associated with an increased risk of uterine cancer and almost never develop into cancer.

Fibroids range in size from seedlings, undetectable by the human eye, to bulky masses that can distort and enlarge the uterus. You can have a single fibroid or multiple ones. In extreme cases, multiple fibroids can expand the uterus so much that it reaches the rib cage.

Many women have uterine fibroids sometime during their lives. But most women don't know they have uterine fibroids because they often cause no symptoms. Your doctor may discover fibroids incidentally during a pelvic exam or prenatal ultrasound.

FIBROID LOCATIONS

Many women who have fibroids don't have any symptoms. In those that do, symptoms can be influenced by the location, size and number of fibroids. In women who have symptoms, the most common symptoms of uterine fibroids include:

• Heavy menstrual bleeding
• Menstrual periods lasting more than a week
• Pelvic pressure or pain
• Frequent urination
• Difficulty emptying the bladder
• Constipation
• Backache or leg pains

Rarely, a fibroid can cause acute pain when it outgrows its blood supply and begins to die. Fibroids are generally classified by their location:

• Intramural fibroids grow within the muscular uterine wall
• Submucosal fibroids bulge into the uterine cavity
• Subserosal fibroids project to the outside of the uterus

WHEN TO SEE A DOCTOR

See your doctor if you have:

• Pelvic pain that doesn't go away
• Overly heavy, prolonged or painful periods
• Spotting or bleeding between periods
• Difficulty emptying your bladder

Seek prompt medical care if you have severe vaginal bleeding or sharp pelvic pain that comes on suddenly.

CAUSES & RISK FACTORS

Doctors don't know the exact cause of uterine fibroids, but research points to these factors:

• Genetic changes: Many fibroids contain altered genes different from normal uterine cells
• Hormones: Estrogen and progesterone appear to promote fibroid growth
• Other growth factors: Substances like insulin-like growth factor may affect growth

Risk factors include:

• Being a woman of reproductive age
• Family history (mother/sister with fibroids)
• Black women have higher risk and earlier onset
• Early menstruation, obesity, vitamin D deficiency
• Diet high in red meat, low in vegetables/fruits
• Alcohol consumption

COMPLICATIONS & PREGNANCY

While usually not dangerous, fibroids can cause:

• Discomfort and pain
• Anemia from heavy blood loss
• Pregnancy complications (in some cases)

Fibroids usually don't interfere with conception but may cause:

• Infertility (especially submucosal fibroids)
• Pregnancy loss
• Placental abruption
• Fetal growth restriction
• Preterm delivery

GYNECOLOGICAL CANCERS

What is gynecologic cancer?
Cancer where cells grow uncontrollably in female reproductive organs. Most common types:

• Endometrial (uterine) cancer
• Ovarian cancer
• Cervical cancer

Less common types involve vulva, Fallopian tube, uterine wall (sarcoma), vagina, and placenta.

UTERINE (ENDOMETRIAL) CANCER

Symptoms:

• Vaginal bleeding/spotting (between periods, post-menopause)
• Abnormal vaginal discharge (watery or bloody)
• Pelvic pain or pressure

Survival Rates:

• 5-year: 82% | 10-year: 79%
• Localized: 95% | Regional spread: 68%

Causes: Excess estrogen, often from obesity or certain medications

Treatment: Most cases treated with hysterectomy; radiation if spread

OVARIAN CANCER

Key facts:

• Less common but more deadly than endometrial cancer
• Often detected late after spreading
• 1 in 60 women develop it

Risk Groups:

• Women with many ovulations (reduced by pregnancy/BC pills)
• 10% from inherited genes (BRCA-1/2, MSH, MLH, etc.)

Symptoms (often late-stage):
Abdominal discomfort, bloating, nausea, appetite loss, urinary symptoms

Treatment: Surgery + chemotherapy for most cases

Cure Rates:
Early stage: 95% | Advanced: 80% remission but high relapse risk

CERVICAL CANCER

Key facts:

• Involves lower uterus (cervix)
• Once most common gynecologic cancer worldwide
• Pap tests have dramatically reduced incidence

Causes: HPV (human papilloma virus) + smoking

Pap Test Guidelines:

• Begin within 3 years of sexual activity or by age 21
• Annual (conventional) or biennial (liquid method) until 30
• After 30: Every 2-3 years if normal results

Treatment:

• Early stage: Highly treatable, fertility-sparing options
• Advanced: Radical surgery or radiation