When Craig Bunk began experiencing severe abdominal pain, blood loss and fatigue, his family doctor thought a stomach ulcer was to blame. Bunk wasn’t so sure.
“My brother Blake died at age 21 from colorectal cancer,” he says. “The disease runs in our family, so I wanted a second opinion.”
Bunk knew just who to call: Patrick Lynch, M.D., a longtime professor of Gastroenterology at MD Anderson. Lynch had treated Blake before his death and identified the genetic mutation that caused the young man’s cancer. Then he’d tested Blake’s family members for the same faulty gene. The results? Blake’s brothers and father had also inherited the mutation that causes a condition known as Lynch syndrome. Named for Lynch’s physician father, Henry Lynch, who helped discover it, the genetic disorder greatly elevates cancer risk.
Lynch syndrome itself is not cancer, but a genetic flaw in one of four genes that repair potentially cancer-causing DNA damage. Normally these “fix-it” genes quickly mend problems before cancer can arise. But they malfunction in people with Lynch syndrome, leaving cancer, especially colon cancer, free to develop.
“With Lynch syndrome, depending on which of the genes is mutated, you have a 10 to 60 percent chance of developing colorectal cancer during your lifetime, a 10 to 40 percent chance of uterine cancer, and up to a 10 percent chance of ovarian cancer,” Lynch explains.
To a lesser extent, the syndrome also increases the risk for small intestine, urinary tract, liver, pancreas, stomach, kidney, brain and skin cancer. Not all people with Lynch syndrome will get cancer, but many will.
Craig Bunk feels lucky to be alive. At MD Anderson, doctors found that his “stomach ulcer” was actually cancer of the small intestine. He underwent surgery to wipe out the tumor before it could spread, and today he’s cancer-free.
“If I’d accepted the ulcer diagnosis,” he says, “I wouldn’t be here now.”
Bunk, now 50, was 35 when his cancer hit, typical of the young age at which most Lynch syndrome patients are diagnosed with cancer.
“Most genetically associated cancers occur by age 50 or younger,” Lynch explains. “Some patients with Lynch syndrome get the same cancer more than once, or develop different cancers at different times.”
Careful, frequent monitoring is the key to treatment.
“We want to catch cancer early when it’s curable,” Lynch says, “or even better, prevent it from happening altogether. With Lynch syndrome, constant vigilance is required.”
Lynch syndrome patients begin colonoscopies at age 20 to 25. People at average risk start at age 50. Lynch syndrome patients repeat their colonoscopies every two years until age 40, then yearly thereafter. People at average risk have colonoscopies once every 10 years.
“Studies show that Lynch syndrome patients who have colonoscopies every couple of years lower their chances of colorectal cancer by 60 percent,” Lynch explains. “During colonoscopies we can detect potentially precancerous growths known as polyps and remove them before they develop into colon cancer.”
Craig Bunk’s father, John, 76, is a testament to this regimen. He undergoes regular colonoscopies at MD Anderson and has had several polyps removed.
“My health is good,” says the semi-retired orthodontist who still sees patients once a month at his Houston-area office.
Craig’s brother, Charles, is a 53-year-old San Antonio lawyer. He was diagnosed with colon cancer at age 49 and kidney cancer at 51. When he’s in Houston for MD Anderson appointments, Charles meets his dad and brother for lunch.
‘We’re all in this together,” he says. “It’s a family affair.”
“Knowing you have Lynch syndrome is half the battle,” Lynch says. “The other half is doing something about it with frequent screenings to prevent cancer or catch it early.”
Yet most people from Lynch syndrome families don’t realize they have it.
“That’s a problem,” says Lynch, “because they’re not taking precautions that can save their lives, such as getting their colons checked more frequently and at younger ages.”
Lynch syndrome affects men and women equally, and parents with the mutation have a 50 percent chance of passing it to their children.
“But if you don’t know you have the defective gene, you’re unwittingly passing it on to the next generation,” Lynch says.
Finding these unknowing Lynch syndrome carriers, he says, could save lives and countless cancer treatment dollars.
In 2009, the Centers for Disease Control and Prevention recommended that everyone diagnosed with colon cancer and their relatives be tested for Lynch syndrome.
Still, just 42 percent of hospitals with cancer programs routinely screen for the condition, according to a survey published in the Journal of Clinical Oncology.
“Lynch syndrome is seriously underdiagnosed,” says Lynch. “Twice as many patients are referred to MD Anderson for the investigation of possible inherited breast cancer than possible inherited colon cancer, even though the two are equally as common.”
Most people have heard of the BRCA hereditary breast cancer genes, he says, but very few have heard of Lynch syndrome.
“Even though colon cancer is the third-leading cause of cancer-related deaths in women in the United States and the second-leading cause in men, it still lacks breast cancer’s panache, high-profile fundraising events, and celebrity-driven awareness campaigns,” Lynch says.
“ ... If you don’t know you have the defective gene, you’re unwittingly passing it on to the next generation.”
Against the odds
The struggle for awareness is not new. Lynch’s father, Henry Lynch, was a medical resident in Nebraska in the 1960s when he began noticing that certain families were plagued by an unusually high incidence of colon and other cancers. He knew there had to be a genetic link in these “cancer clusters,” as he called them, but the medical community scorned this idea. Cancer at the time was believed to be caused by environmental elements like chemicals and pesticides.
Hammerin’ Hank – Lynch’s moniker after a brief stint as a teenage boxer – persisted. Despite minimal financial support, he spent decades painstakingly compiling data that demonstrated patterns of cancer through multiple generations of almost 3,000 families. With his wife, Jane, a psychiatric nurse, Lynch and staffers traveled around the nation, meeting with family members, drawing their blood, taking detailed medical and family histories and advising them.
In the 1990s he was vindicated when scientists discovered the genes behind what today is called Lynch syndrome.
“Against the odds he kept going,” says Patrick Lynch. “He bucked conventional wisdom and his research became a game-changer. He identified a link between genetics and some cancers at a time when the idea was thought to be ludicrous.”
Today, Henry Lynch, 89, still heads the Hereditary Cancer Center at Creighton University in Nebraska, where he’s been on faculty since 1967 – minus a two-year stretch as an MD Anderson faculty member in the 1960s.
Picking up the torch
In Houston, Patrick Lynch carries on the campaign to raise Lynch syndrome awareness. He’s working with software developers to create a program that enables family histories to be collected online, making outreach to at-risk relatives easier.
“Each patient lists email addresses and demographic information for siblings, cousins, aunts and uncles … every relative they can think of,” Lynch explains.
As the document grows, those relatives are notified by email and invited to “add to” the digital family tree by listing additional relatives, who in turn receive an email invitation.
“It’s a snowball effect,” Lynch says. “The goal is to notify as many family members as possible, and get them to the lab for testing.”
The program, called Family Connect, is still in the works and slated for completion in a year. Lynch plans to share it with other health care institutions, free of charge.