Dr. Bhavesh Balar is a board-certified hematologist and oncologist on staff at CentraState Medical Center in Freehold, NJ, where he serves as chairman of the hospital’s Cancer Committee. He is also a medical director at Regional Cancer Care Associates in New Jersey. He contributed this article to Live Science's Expert Voices: Op-Ed & Insights.
As an oncologist, I'm frequently asked why so many people these days are being diagnosed with cancer. Considering the significant inroads we've made over the past 50 years in terms of cancer research, prevention, diagnosis and treatment, it doesn't seem to make sense.
The good news is that each of us is more likely to survive a cancer diagnosis and go on to enjoy a high quality of life than at any other time in history. There are estimated to be nearly 14.5 million cancer survivors in the United States.
While there are several factors contributing to the increase in cancer diagnoses, there are three main reasons which account for most of the cancer cases in the U.S.
1. Older people get cancer most often, and we're getting older
Like heart disease, cancer largely affects the senior population. About 77 percent of all cancers are diagnosed in people over age 55, a segment of the U.S. population that is expected to double by 2060. Therefore, more seniors means more cases of cancer. Keep in mind, seniors are also living decades longer than just a century ago, when you were not expected to live beyond your mid-50s. According to the National Cancer Institute, seniors have an average life expectancy of about 79 years, on average, while 73 is the median age of cancer death.
2. Obesity opens the door to several types of cancer
A second key factor in our rising cancer rates is our country's battle with obesity and the continued lack of proper diet, exercise and weight control for many Americans. In 2014, the American Society of Clinical Oncology (ASCO) issued a report warning that obesity will soon overtake tobacco as the No. 1 risk factor for cancer. Obesity is associated with increased risk of the following cancer types: breast (after menopause), colon and rectal, esophageal, endometrial, pancreatic, kidney, thyroid and gallbladder.
3. Certain cancer types are on the rise
Despite increased awareness, there are some cancer types that continue to gain ground and contribute to the cancer increase:
HPV. Human papillomavirus (HPV) is the most common sexually transmitted disease, and consists of 40 different mutations, according to the U.S. Centers for Disease Control (CDC), which also reports that 79 million Americans are infected, most of whom have no outward symptoms. U.S. Food and Drug Administration (FDA)-approved vaccines can protect against some of the most common types. Head and neck cancers are increasingly attributed to HPV, including cancers in the back of the throat, most commonly in the base of the tongue and tonsils. In addition, high-risk types can cause cancer of the cervix, vagina, vulva, anus and penis. [Protect Your Teen from HPV, Prevent Deadly Cancers (Op-Ed)]
The virus can cause normal cells in infected skin to become abnormal. In most cases, the body fights off the HPV infection naturally and infected cells then go back to normal. But in cases when the body does not fight off the virus, HPV can cause cellular changes that may eventually turn into cancer years after the initial infection.
Gastrointestinal cancers. These cancers affect the digestive system — the stomach, gallbladder, liver, pancreas and bowel (small intestine, large intestine or colon , and rectum). ESPN anchor Stuart Scott lost his long battle with appendiceal (appendix) cancer in early 2015, which has recently brought more attention to these lesser-known cancer types.
Gastroesophageal adenocarcinomas (stomach cancer) as well as pancreatic, liver and kidney cancers have increased recently. Again, obesity may play a role here. About half of liver cancers in the United States are among people with chronic hepatitis C infections, and the increase in incidence is consistent with the aging of the hepatitis C-infected population. Cancers in that region of the body can be particularly difficult to diagnose, as symptoms often present similarly to less-threatening conditions, such as irritable bowel syndrome or acid reflux. This allows the cancer to spread, undiagnosed and untreated. [Want to Cut Your Cancer Risk? Lose That Weight (Op-Ed )]
Skin cancer. One of the most preventable cancers continues its reign as the most common. Despite efforts to address skin cancer risk factors, such as inadequate sun protection and intentional tanning behaviors, skin cancer rates — including rates of melanoma — have increased in the United States every year since 2001, according to the CDC. Many Americans tan intentionally for cosmetic reasons, and by doing so increase their risk. The U.S. Surgeon General reported that 33 percent of Americans experienced a sunburn, a key skin cancer risk factor, in 2014. The two most common skin cancer types are basal cell and squamous cell, which usually form on the head, face, neck, hands and arms. Melanoma accounts for less than two percent of skin cancer cases — but results in the most deaths. A bright spot is that non-melanoma cancers are being diagnosed and treated earlier and with more success.
Earlier diagnosis leads to more successful outcomes
Keep in mind, more people are diagnosed with cancer because of the plethora of cancer-specific screenings that are available today. Like many life-threatening medical conditions, early diagnosis can increase your likelihood of beating the disease and going on to live a long life.
Thankfully, in this day and age, receiving a cancer diagnosis is no longer a death sentence.
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