Tag Archives: cancer

“Relaxers And Hair Dyes May Increase The Risk Of Breast Cancer In Black Women”, says alexandra white.

Alexandra White, Ph.D., head of the National Institute of Environmental Health Sciences Environment and Cancer Epidemiology Group and senior author of the study, said on Twitter:

“In our study, we see a higher breast cancer risk associated with hair dye use, and the effect is stronger in African American women, particularly those who are frequent users.”


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According to the study released by the International Journal of Cancer, all women who regularly use permanent hair dye and hair relaxers are more likely to develop breast cancer than women who didn’t use hair dye.

The study authors wrote that the specific chemical found in the hair dyes that could be carcinogenic has not been detected yet. There are over 5,000 chemical ingredients present in various hair dyes. Some of these are known to be carcinogenic and some are capable of damaging the genes and cause mutations.

According to the study, “Many hair products contain endocrine-disrupting compounds and carcinogens potentially relevant to breast cancer. Products used predominately by black women may contain more hormonally-active compounds.”

5 Early symptoms of Cancer In Men!! All Men Should Know

Knowing early symptoms of cancer can help you seek treatment sooner to better your chances of remission. This article is really important so read carefully to the end.

Male hands holding prostate cancer awareness ribbon with mustache – stock photo

Here are 5 early symptoms of cancer in men:

1.Blood in your pee or stool

One of the best ways to fight the disease is to catch it in the early stages when it’s more treatable. The problem is that the warning signs for many kinds of cancer can seem pretty mild.
Blood in your pee or stool
It is very important to visit the doctor when you notice blood in your pee or stool because it could be first signs of cancer of the bladder, kidneys, or colon. Although you’re more likely to have a problem that’s not cancer, like hemorrhoids or a urinary infection, it’s important to treat it at the early stages.

2.Urinary changes

Urinary changes may develop as you age but certain symptoms may indicate prostate cancer. Prostate cancer is most common in men ages 60 and older.
Common urinary symptoms include:

  • Urinary leaks
  • Incontinence
  • An inability to urinate despite urges to go
  • Delayed urination
  • Straining during urination

3.Persistent back pain

Back pain may be a symptom of cancer. Symptoms of cancer may not show until it has spread to other parts of your body, such as the bones of your spine. For example, prostate cancer is especially prone to spread to the bones and may cause these symptoms within your hip bones and lower back.

Unlike occasional muscle pain, cancer of the bone causes tenderness and discomfort in your bones.

4.Unusual coughing

A persistent cough is an early sign of lung cancer. If you don’t have any other related symptoms, such as a stuffy nose or fever, the cough probably isn’t due to a virus or infection.

Coughing accompanied with bloody mucus is also associated with lung cancer in men.

5.Changes in your testicles

If you notice a lump, heaviness, or any other change in your testicle, never delay having it looked at,” says Herbert Lepor, MD, urology chairman at New York University Langone Medical Center.

“Unlike prostate cancer, which grows slowly, testicular cancer can take off overnight.” Your doctor will look for any problems with a physical exam, blood tests, and an ultrasound of your scrotum.

10 facts about cancer you probably don’t but MUST know

Cancer is one of the leading causes of death in our world today. Take a look at this facts and maybe they can be a benefit to you.

1

Tobacco use is the cause of about 22% of cancer deaths

2

People may become anxious or depressed post-diagnosis. The risk of suicide in people with cancer is approximately double.

3

Cancer can be difficult to diagnose and can be considered a “great imitator. So it’s better to go for regular checkups at a standard medical center

4

Everyone has a small chance of developing lung cancer as a result of air pollution or radiation.

5

Tobacco smoke contains over fifty known carcinogens, including nitrosamines and polycyclic aromatic hydrocarbons.

Read also: Stomach cancer

6

Diet, physical inactivity and obesity are related to up to 30–35% of cancer deaths.

7

Children are twice as likely to develop radiation-induced leukemia as adults.

8

Taller people have an increased risk of cancer because they have more cells than shorter people.

9

About 99% of cases involving postrate cancer occur in males over the age of 50.

10

Lower blood levels of vitamin D may increase the risk of developing prostate cancer.

Read also: 5 early symptoms of cancer in men

Stomach Cancer Is A Silent Killer! Here Are The Signs And Symptoms

Stomach cancer, also known as gastric cancer, is a cancer that develops from the lining of the stomach. It can may spread from the stomach to other parts of the body, particularly the liver, lungs, bones, lining of the abdomen and lymph nodes.

In the United States, five-year survival is 28%,while in South Korea it is over 65%, partly due to screening efforts.

Globally, stomach cancer is the fifth leading type of cancer and the third leading cause of death from cancer, making up 7% of cases and 9% of deaths.

In 2012, it newly occurred in 950,000 people and caused 723,000 deaths.

The cause is believed to be due to the eating of less salted and pickled foods as a result of the development of refrigeration as a method of keeping food fresh.

Stomach cancer occurs most commonly in East Asia and Eastern Europe and it occurs twice as often in males as in females.

Symptoms Of Cancer

These may include :

  • heartburn, upper abdominal pain, nausea and loss of appetite.

Later signs and symptoms may include:

  • weight loss,
  • yellowing of the skin and whites of the eyes,
  • difficulty swallowing and blood in the stool among others.
  • a sensation of being very full during meals
  • feeling bloated after meals
  • frequent burping
  • heartburn
  • indigestion that does not resolve
  • stomach ache
  • pain in the breastbone
  • trapped wind
  • vomiting, which may contain blood.

However, many of these symptoms are very similar to those of other, less serious conditions. However, anyone with an increased risk for stomach cancer who experiences swallowing difficulties should seek prompt medical treatment.
As the stomach cancer becomes more advanced, some people might experience the following symptoms:

  • anemia
  • a buildup of fluid in the stomach, which may cause the stomach to feel lumpy to the touch
  • black stools that contain blood
  • fatigue
  • loss of appetite
  • weight loss

Risk Factor

  • Smoking,
  • Dietary factors such as pickled vegetables and obesity are other risk factors.

About 10% of cases run in families, and between 1% and 3% of cases are due to genetic syndromes inherited from a person’s parents such as hereditary diffuse gastric cancer. Most cases of stomach cancers are gastric carcinomas.

Most of the time, stomach cancer develops in stages over years.

Diagnosis is usually by biopsy done during endoscopy.

This is followed by medical imaging to determine if the disease has spread to other parts of the body.

Japan and South Korea, two countries that have high rates of the disease, screen for stomach cancer.

A Mediterranean diet lowers the risk of cancer as does the stopping of smoking.

READ ALSO: Penile Cancer (cancer of the penis)

Treatment

Treatments may include:

  • some combination of surgery,
  • chemotherapy,
  • radiation therapy and
  • targeted therapy.

If treated late, palliative care may be advised.

Outcomes are often poor with a less than 10% five-year survival rate globally.

This is largely because most people with the condition present with advanced disease.

Read also: 5 early symptoms of cancer all men should know

Causes

Here are some of the causes ;

Gastric cancer occurs as a result of many factors. It occurs twice as commonly in males as females.

Estrogen may protect women against the development of this form of cancer.

Infections

Helicobacter pylori infection is an essential risk factor in 65–80% of gastric cancers, but only 2% of people with Helicobacter infections develop stomach cancer.

Smoking

Smoking increases the risk of developing gastric cancer significantly, from 40% increased risk for current smokers to 82% increase for heavy smokers.

Gastric cancers due to smoking mostly occur in the upper part of the stomach near the esophagus.

Some studies show increased risk with alcohol consumption as well.

READ FULL ARTICLE ON STOMACH CANCER HERE

Signs and symptoms all women must know about Breast cancer

Breast cancer is cancer that develops from breast tissue. In those with distant spread of the disease, there may be bone pain, swollen lymph nodes, shortness of breath, or yellow skin.

Symptoms
Lump in a breast, change in breast shape, dimpling of the skin, fluid coming from the nipple, a newly inverted nipple, red scaly patch of skin

Read also: 5 early symptoms of cancer all men should know

Signs and symptoms

The first noticeable symptom of breast cancer is typically a lump that feels different from the rest of the breast tissue. More than 80% of breast cancer cases are discovered when the woman feels a lump. Lumps found in lymph nodes located in the armpits can also indicate breast cancer.

Indications of breast cancer other than a lump may include thickening different from the other breast tissue, one breast becoming larger or lower, skin puckering or dimpling, a rash on or around a nipple, a nipple changing position or shape or becoming inverted, discharge from nipple(s), constant pain in part of the breast or armpit, and swelling beneath the armpit or around the collarbone. Pain in the breast is an unreliable tool in determining the presence or absence of breast cancer, but may be indicative of other breast health issues.

Paget’s disease of the breast.

This syndrome presents as skin changes resembling eczema, such as redness, discoloration, or mild flaking of the nipple skin. As Paget’s disease of the breast advances, symptoms may include tingling, itching, increased sensitivity, burning, and pain. There may also be discharge from the nipple. Approximately half of women diagnosed with Paget’s disease of the breast also have a lump in the breast.

Inflammatory Breast Cancer presents with similar effects. Inflammatory Breast Cancer is a rare (only seen in less than 5% of breast cancer diagnosis) yet aggressive form of breast cancer characterized by the swollen, red areas formed on the top of the Breast. The visual effects of Inflammatory Breast Cancer is a result of a blockage of lymph vessels by cancer cells. This type of breast cancer is seen in more commonly diagnosed in younger ages, obese women, and African American women. As inflammatory breast cancer does not present as a lump there can sometimes be a delay in diagnosis.

What can cause breast cancer

obesity, lack of exercise, alcohol, hormone replacement therapy during menopause, ionizing radiation, early age at first menstruation, having children late or not at all, older age, prior breast cancer, family history.

6 gynaecological cancer symptoms

6 gynaecological cancer symptoms it’s easy to miss

From cervical, to womb and vulval.
Gynaecological cancer symptoms: A doctor reveals the signs it’s easy to miss
With fewer women than ever attending their smear tests, gynaecological cancer is affecting more than 21,000 of us a year, according to the Eve Appeal – and while cervical cancer is a part of that, it doesn’t make up the whole picture.

There are five different gynaecological cancers: Womb, ovarian, cervical, vulval and vaginal. Each one has different symptoms – although there are crossovers – and as familiar as we may be with our bodies, they can be easy to miss.

It’s understandable that we would pass many signs of gynaecological cancers off as hormonal changes, so how should we know what to be looking for, and when should we seek medical help?

Tim Woodman, Medical Director for Bupa UK, shared with Cosmopolitan UK the bodily changes that could require a visit to your GP:

1. Abnormal vaginal bleeding or discharge

“If you’ve noticed any bleeding between periods, bleeding after intercourse or post-menopausal bleeding, it’s important to make your GP aware,” Tim explains.

Whilst there are many causes of abnormal bleeding or discharge, this could be a sign of cervical and womb cancer.

“But remember that abnormal bleeding or discharge is also very common and many women experience at some point in their lives when there is no cause for concern.”

2. Changes in your bathroom habits

Bowel habits vary a lot in different people, but if you notice persistent changes to your toilet habits for a few weeks, such as gas, nausea, diarrhoea or constipation, you should speak to your doctor.

Bowel problems are very common and usually they’re not related to cancer, however it’s important to get these checked out just in case.”

3. Constant fatigue

Ordinarily, if you are feeling tired, a little rest is all you need to recover. However, if you’ve noticed that you’re feeling constantly fatigued and it’s preventing you from working or carrying out your daily activities, you should mention this to your GP as this could be a symptom of ovarian cancer.”

4. A bloated tummy

If you’ve been feeling bloated most days for the last few weeks, you should tell your GP.

Chances are it’s nothing serious and could be caused by other conditions, such as irritable bowel syndrome (IBS) or pre-menstrual stress (PMS), but you should still get this checked out as it can also be a symptom of ovarian cancer.

At your appointment, your doctor should gently feel your tummy and ask you about your symptoms and general health.”

5. Lumps, bumps and ulcers

“A common symptom of vulval cancers are lumps and bumps around your genitals. If you’ve noticed pain, a lump or growth on the vulva, you should get this checked out.

“While it’s highly unlikely to be the result of cancer, these changes should be investigated. It can be daunting or make you feel embarrassed to discuss these types of symptoms, however it’s important to make your doctor aware of these changes as early as possible.

“If you’re worried about mentioning this to your doctor, it might make you feel more at ease discussing your symptoms with a female medical professional or writing down your symptoms. And remember, you won’t be the first person they’ve seen with similar concerns.”

6. Abdominal or pelvic pain

“If you’ve been experiencing frequent pain or discomfort in your pelvic or abdominal area for a few weeks, you should speak to your doctor.

“Pain in these areas can be caused by many different conditions, but again, it’s important to get this checked out by a medical professional just to be on the safe side.”

These pains are considered to be symptoms of womb, ovarian and cervical cancers.

Since many of the gynaecological cancer symptoms are likely to be something we’ve all experienced from time to time, it’s important to remember that there could be many reasons behind the bodily changes – and there’s every chance they’re nothing to worry about.

However, as with any symptoms that last longer than a few weeks, it’s always worth visiting your GP to investigate and put your mind at ease.

Tim explains: “Whatever the symptoms, when you notice a change in your body it can be daunting to speak about, but your doctor should help to provide you with peace of mind or signpost you to the most appropriate support and if necessary, treatment.”

cosmopolitan.com

Penile Cancer

Penile Cancer is a malignant growth found on the skin or in the tissues of the penis. Around 95% of penile cancers are squamous cell carcinomas. Other types of penile cancer such as Merkel cell carcinoma, small cell carcinoma, melanoma and other are generally rare.

Signs and symptoms

  1. Redness of the penis
  2. Rash on the penis
  3. Foul smelling discharge from the penis
  4. Pain in the penis
  5. Growth or sore on the penis that doesn’t heal within four weeks (may look like a wart, ulcer, or blister), may or may not be painful
  6. Bleeding from the penis or from under the foreskin
  7. Change in color of the penis
  8. Phimosis

Infections
HIV infection—HIV-positive men have eight-fold increased risk of developing penile cancer than HIV-negative men.

Human papillomavirus—HPV is a risk factor in the development of penile cancer. According to the Center for Disease Control and Prevention (CDC), HPV is responsible for about 800 (about 40%) of 1,570 cases of penile cancer diagnosed annually in the United States. There are more than 120 types of HPV.

Read also: Cancer

Genital warts—Genital or perianal warts increase the risk of invasive penile cancer by about 3.7 times if they occurred more than two years before the reference date. About half of men with penile cancer also have genital warts, which are caused by HPV.

Read Also: Postrate Cancer

Hygiene and injury
Poor hygiene—Poor hygiene can increase a man’s risk of penile cancer.

Smegma—Smegma, a whitish substance that can accumulate beneath the foreskin, is associated with greater risk of penile cancer.

The American Cancer Society suggests that smegma may not be carcinogenic, but may increase the risk by causing irritation and inflammation of the penis.
Balanitis and penile injury—Inflammation of the foreskin and/or the glans penis (balanitis) is associated with about 3.1 times increased risk of penile cancer.

It is usually caused by poor hygiene, allergic reactions to certain soaps, or an underlying health condition such as reactive arthritis, infection, or diabetes. Small tears and abrasions of the penis are associated with about 3.9 times increased risk of cancer.

Phimosis—Phimosis is a medical condition where the foreskin cannot be fully retracted over the glans. It is considered a significant risk factor in the development of penile cancer (odds ratio of 38–65). Phimosis may also be a symptom of penile cancer.

Paraphimosis—Paraphimosis is a medical condition where the foreskin becomes trapped behind the glans. It is considered a risk factor for the development of penile cancer.

Circumcision—Some studies show that circumcision during infancy or in childhood may provide partial protection against penile cancer, but this is not the case when performed in adulthood.

It has been suggested that the reduction in risk may be due to reduced risk of phimosis; other possible mechanisms include reduction in risk of smegma and HPV infection.

Age

Penile cancer is rarely seen in men under the age of 50. About 4 out of 5 men diagnosed with penile cancer are over the age of 55.

Lichen sclerosus

Lichen sclerosus is a disease causing white patches on the skin. Lichen sclerosus increases the risk of penile cancer.

As the exact cause of lichen sclerosus is unknown, there is no known way to prevent it.

Tobacco

Chewing or smoking tobacco increases the risk of penile cancer by 1.5–6 times depending on the duration smoking and daily number of cigarettes.

Ultraviolet light

Men with psoriasis who have been treated using UV light and a drug known as psoralen have an increased risk of penile cancer.

Penile cancer arises from precursor lesions, which generally progress from low-grade to high-grade lesions. For HPV related penile cancers this sequence is as follows:

  1. Squamous hyperplasia;
  2. Low-grade penile intraepithelial neoplasia (PIN);
  3. High-grade PIN (carcinoma in situ—Bowen’s disease, Erythroplasia of Queyrat and bowenoid papulosis (BP));
  4. Invasive carcinoma of the penis.

However, in some cases non-dysplastic or mildly dysplastic lesions may progress directly into cancer. Examples include flat penile lesions (FPL) and condylomata acuminata.

In HPV negative cancers the most common precursor lesion is lichen sclerosus (LS).

Classification
Around 95% of penile cancers are squamous cell carcinomas. They are classified into the following types

  1. basaloid (4%)
  2. warty (6%)
  3. mixed warty-basaloid (17%)
  4. verrucous (8%)
  5. papillary (7%)
  6. other SCC mixed (7%)
  7. sarcomatoid carcinomas (1%)
  8. not otherwise specified (49%)

Other types of carcinomas are rare and may include small cell, Merkel cell, clear cell, sebaceous cell or basal cell tumors. Non-epithelial malignancies such as melanomas and sarcomas are even more rare.

Like many malignancies, penile cancer can spread to other parts of the body. It is usually a primary malignancy, the initial place from which a cancer spreads in the body. Much less often it is a secondary malignancy, one in which the cancer has spread to the penis from elsewhere.

The staging of penile cancer is determined by the extent of tumor invasion, nodal metastasis, and distant metastasis.

Cancer

Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.

They form a subset of neoplasms. A neoplasm or tumor is a group of cells that have undergone unregulated growth and will often form a mass or lump, but may be distributed diffusely.

All tumor cells show the six hallmarks of cancer. These characteristics are required to produce a malignant tumor. They include:

  • Cell growth and division absent the proper signals
  • Continuous growth and division even given contrary signals
  • Avoidance of programmed cell death
  • Limitless number of cell divisions
  • Promoting blood vessel construction
  • Invasion of tissue and formation of metastases
  • Metastases is the spread of cancer to other locations in the body. The dispersed tumors are called metastatic tumors, while the original is called the primary tumor. Almost all cancers can metastasize. Most cancer deaths are due to cancer that has metastasized

The progression from normal cells to cells that can form a detectable mass to outright cancer involves multiple steps known as malignant progression.

These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. While these symptoms may indicate cancer, they can also have other causes. Over 100 types of cancers affect humans.

Tobacco use is the cause of about 22% of cancer deaths. Another 10% are due to obesity, poor diet, lack of physical activity or excessive drinking of alcohol. Other factors include certain infections, exposure to ionizing radiation and environmental pollutants.

In the developing world, 15% of cancers are due to infections such as Helicobacter pylori, hepatitis B, hepatitis C, human papillomavirus infection, Epstein–Barr virus and human immunodeficiency virus (HIV).

READ ALSO: WHAT IS PROSTATE CANCER

These factors act, at least partly, by changing the genes of a cell. Typically, many genetic changes are required before cancer develops.

Approximately 5–10% of cancers are due to inherited genetic defects from a person’s parents. Cancer can be detected by certain signs and symptoms or screening tests. It is then typically further investigated by medical imaging and confirmed by biopsy.

Many cancers can be prevented by not smoking, maintaining a healthy weight, not drinking too much alcohol, eating plenty of vegetables, fruits and whole grains, vaccination against certain infectious diseases, not eating too much processed and red meat and avoiding too much sunlight exposure.

Early detection through screening is useful for cervical and colorectal cancer. The benefits of screening in breast cancer are controversial.

Cancer is often treated with some combination of radiation therapy, surgery, chemotherapy and targeted therapy. Pain and symptom management are an important part of care.

Palliative care is particularly important in people with advanced disease. The chance of survival depends on the type of cancer and extent of disease at the start of treatment.

In children under 15 at diagnosis, the five-year survival rate in the developed world is on average 80%. For cancer in the United States, the average five-year survival rate is 66%.

The most common types of cancer in males are lung cancer, prostate cancer, colorectal cancer and stomach cancer. In females, the most common types are breast cancer, colorectal cancer, lung cancer and cervical cancer.

If skin cancer other than melanoma were included in total new cancer cases each year, it would account for around 40% of cases.

In children, acute lymphoblastic leukemia and brain tumors are most common, except in Africa where non-Hodgkin lymphoma occurs more often. In 2012, about 165,000 children under 15 years of age were diagnosed with cancer.

The risk of cancer increases significantly with age, and many cancers occur more commonly in developed countries. Rates are increasing as more people live to an old age and as lifestyle changes occur in the developing world.

Causes of cancer

The majority of cancers, some 90–95% of cases, are due to genetic mutations from environmental and lifestyle factors. The remaining 5–10% are due to inherited genetics.

Environmental, as used by cancer researchers, means any cause that is not inherited genetically, such as lifestyle, economic, and behavioral factors and not merely pollution.

Common environmental factors that contribute to cancer death include tobacco (25–30%), diet and obesity (30–35%), infections (15–20%), radiation (both ionizing and non-ionizing, up to 10%), stress, lack of physical activity and pollution.

It is not generally possible to prove what caused a particular cancer because the various causes do not have specific fingerprints.

For example, if a person who uses tobacco heavily develops lung cancer, then it was probably caused by the tobacco use, but since everyone has a small chance of developing lung cancer as a result of air pollution or radiation, the cancer may have developed for one of those reasons.

Excepting the rare transmissions that occur with pregnancies and occasional organ donors, cancer is generally not a transmissible disease.

Exposure to particular substances have been linked to specific types of cancer. These substances are called carcinogens.

Tobacco

Tobacco is responsible for about one in five cancer deaths worldwide and about one in three in the developed world.

Tobacco smoke causes 90% of lung cancer. It also causes cancer in the larynx, head, neck, stomach, bladder, kidney, esophagus and pancreas.

Tobacco smoke contains over fifty known carcinogens, including nitrosamines and polycyclic aromatic hydrocarbons.

Lung cancer death rates in the United States have mirrored smoking patterns, with increases in smoking followed by dramatic increases in lung cancer death rates and, more recently,

In the United States, excess body weight is associated with the development of many types of cancer and is a factor in 14–20% of cancer deaths. A UK study including data on over 5 million people showed higher body mass index to be related to at least 10 types of cancer and responsible for around 12,000 cases each year in that country.

Diet and weight

Physical inactivity is believed to contribute to cancer risk, not only through its effect on body weight but also through negative effects on the immune system and endocrine system.

More than half of the effect from diet is due to overnutrition (eating too much), rather than from eating too few vegetables or other healthful foods.

A high-salt diet is linked to gastric cancer. Aflatoxin B1, a frequent food contaminant, causes liver cancer. Betel nut chewing can cause oral cancer. National differences in dietary practices may partly explain differences in cancer incidence. For example, gastric cancer is more common in Japan due to its high-salt diet while colon cancer is more common in the United States. Immigrant cancer profiles mirror those of their new country, often within one generation.

Infections

Worldwide approximately 18% of cancer deaths are related to infectious diseases. This proportion ranges from a high of 25% in Africa to less than 10% in the developed world.

Viruses are the usual infectious agents that cause cancer but cancer bacteria and parasites may also play a role.

Oncoviruses are viruses that causes cancer. They include:
human papillomavirus (cervical cancer), Epstein–Barr virus (B-cell lymphoproliferative disease and nasopharyngeal carcinoma), Kaposi’s sarcoma herpesvirus (Kaposi’s sarcoma and primary effusion lymphomas), hepatitis B and hepatitis C viruses (hepatocellular carcinoma) and human T-cell leukemia virus-1

Radiation

Up to 10% of invasive cancers are related to radiation exposure, including both ionizing radiation and non-ionizing ultraviolet radiation.

Additionally, the majority of non-invasive cancers are non-melanoma skin cancers caused by non-ionizing ultraviolet radiation, mostly from sunlight. Sources of ionizing radiation include medical imaging and radon gas.

Hereditary
The vast majority of cancers are non-hereditary (sporadic). Hereditary cancers are primarily caused by an inherited genetic defect. Less than 0.3% of the population are carriers of a genetic mutation that has a large effect on cancer risk and these cause less than 3–10% of cancer.

Some of these syndromes include: certain inherited mutations in the genes BRCA1 and BRCA2 with a more than 75% risk of breast cancer and ovarian cancer, and hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome), which is present in about 3% of people with colorectal cancer, among others.

Physical Agents

Some substances cause cancer primarily through their physical, rather than chemical, effects.

A prominent example of this is prolonged exposure to asbestos, naturally occurring mineral fibers that are a major cause of mesothelioma (cancer of the serous membrane) usually the serous membrane surrounding the lungs.

Other substances in this category, including both naturally occurring and synthetic asbestos-like fibers, such as wollastonite, attapulgite, glass wool and rock wool, are believed to have similar effects.

Non-fibrous particulate materials that cause cancer include powdered metallic cobalt and nickel and crystalline silica (quartz, cristobalite and tridymite).

Usually, physical carcinogens must get inside the body (such as through inhalation) and require years of exposure to produce cancer.

Hormones

Some hormones play a role in the development of cancer by promoting cell proliferation.

Insulin-like growth factors and their binding proteins play a key role in cancer cell proliferation, differentiation and apoptosis, suggesting possible involvement in carcinogenesis.

Hormones are important agents in sex-related cancers, such as cancer of the breast, endometrium, prostate, ovary and testis and also of thyroid cancer and bone cancer.

For example, the daughters of women who have breast cancer have significantly higher levels of estrogen and progesterone than the daughters of women without breast cancer.

These higher hormone levels may explain their higher risk of breast cancer, even in the absence of a breast-cancer gene.

Similarly, men of African ancestry have significantly higher levels of testosterone than men of European ancestry and have a correspondingly higher level of prostate cancer.

Men of Asian ancestry, with the lowest levels of testosterone-activating androstanediol glucuronide, have the lowest levels of prostate cancer.

Read also: Postrate Cancer