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Is Your Colorectal Cancer Tumor on the Right or Left Side of Your Body?

By U.S. News & World Report

Cancers that develop in the colon are not all the same. Where they originate in the colon has important survival and treatment implications.

Geography of the Bowel

At 5-feet long, the colon makes up the bulk of the large intestine, which is also called the bowel. The colon removes nutrients from the food you eat and eliminates solid waste. The rectum and anal canal constitute the last part of the large intestine. Together, they are about 6 to 8 inches long. The colon begins on the right side of your body (the proximal colon) at the end of the small intestine and travels upwards toward your head. It crosses across your body (the transverse colon) and then descends downwards toward the rectum. This is the distal, or descending, colon.

Embryologically, these sections of the colon are different, says Dr. John Mansour, a surgical oncologist at the UT Southwestern Medical Center’s Simmons Comprehensive Cancer Center. In a fetus, the right colon arises from the mid gut, and the left colon arises from the hind gut. They fuse together at the transverse colon during development. Although visually the colon appears as one continuous tube, colorectal cancer tumors don’t just develop in different spots in the same tube. We don’t understand all the reasons why side is important in where colon cancers develop, Mansour says.

[See: 8 Questions to Ask Your Doctor About Colon Cancer.]

The Difference between Tumors on the Left and Right Side of the Colon

“Colorectal cancer is not a [single] disease,” says Dr. Dale R. Shepard, a medical oncologist at the Cleveland Clinic. “[If you look at the] proteins and pathways, there are clear differences in the pathology of tumors on the left and right side.”

As Mansour says: “Initially, doctors noticed right-sided tumors were more likely to present at a later [more advanced] stage. We thought it was because they were further upstream. That may be part of it, but there are real differences [in the tumors as well]. In 2001, [we began to notice] differences in survival. People with left-sided tumors live longer.”

In fact, according to a large, phase 3 clinical trial, colorectal cancer patients with left-sided tumors lived more than a year longer after initial treatment than patients with right-sided tumors.

Eventually, doctors learned that the side where the tumor originated also made a difference in treatment outcomes. CRC patients who have the normal version of a gene called KRAS wild-type (which is known to predict response to certain therapies) responded well when treated with cetuximab. Cetuximab is a type of targeted therapy normally prescribed for people with metastatic colorectal cancer. Mansour says a study showed that people with normal KRAS wild-type had an overall survival rate that was significantly better in left-sided cancers.

[See: 10 Seemingly Innocent Symptoms You Shouldn’t Ignore.]

However, Mansour says, if CRC patients had the mutated version of the KRAS wild-type gene, cetuximab did not help them. “These patients did better with bevacizumab [a different targeted therapy].”

Mansour says a 2016 randomized trial looked at patients with only metastasized KRAS wild-type tumors (the normal version) and found that overall survival in patients with left-sided tumors was much better (36 months) compared to those with right sided tumors (16 months). “The [overall survival] was different, even though the cancer had spread,” he says. “This is really important.”

Tumor sidedness affects certain populations more than others: African-Americans, who tend to develop CRC at younger ages and to be diagnosed at more advanced stages, are more likely to have right-sided tumors, Shepard says. And people with Lynch syndrome, a genetic disorder that significantly raises the risk of colon cancer, are also likely to have right-sided tumors.

It’s not because the tumor starts on the right or left side, Mansour says: “Sidedness is a surrogate for genetic differences in tumors.” Future CRC research will continue to shed light on these differences, which will help drive the development of better treatment options. The future of colon cancer care is increasingly going to depend upon the unique characteristics of each individual’s cancer, and treatment will be much more sophisticated.

So far, it appears sidedness does not affect whether or not primary CRC will recur after treatment. However, when colorectal cancer does recur, right-sided tumors still have a worse prognosis or are more aggressive than left-sided tumors.

[See: 10 Ways to Prepare for Surgery.]

If you’re a patient with CRC, ask your doctor about optimal therapies for your specific type of cancer. Shepard says many of the findings regarding the sidedness of colon cancer tumors came from looking back at other studies. Most doctors want to see primary studies that specifically address the topic of sidedness before they adopt treatment changes. For now, it’s another consideration in overall patient treatment decisions.

More from U.S. News

8 Questions to Ask Your Doctor About Colon Cancer

6 Options for People Who Don’t Want a Colonoscopy

10 Weird Things That Can Make You Poop

Is Your Colorectal Cancer Tumor on the Right or Left Side of Your Body? originally appeared on usnews.com

Don’t Settle for Student Loans to Pay for Online Education

By WTOP Staff
Online college programs are becoming a more popular choice for prospective students, with one study finding that more than 6 million students enrolled in at least one online course in fall 2015. The popularity of these courses can be attributed in part to their flexibility with working adults' schedules, students' ability to progress more quickly through online programs and, oftentimes, cheaper tuition. [See 10 low-cost online bachelor's programs for out-of-state students.]Online degrees can be beneficial to many college students, but some studies have shown online learners complete their programs at lower rates than students at traditional brick-and-mortar campuses. Individuals with student loans but no degree comprise two-thirds of defaulted borrowers. Though these numbers are not encouraging, just like for traditional programs, there are ways to reduce how much you'll need to borrow for an online program to ensure you won't become one of these statistics. Don't just settle on borrowing student loans to cover the whole cost of your program and living expenses. Instead, start thinking about how to cut costs and cover your balance in different ways, such as the following. -- Grants and scholarships: Even though you are taking an online course, you can still apply and receive grants and scholarships. But your first step should be to complete the Free Application for Federal Student Aid, commonly referred to as the FAFSA, which will allow you to receive a Pell Grant if your expected family contribution is low enough. The EFC criteria and award amounts are adjusted annually, but the 2017-2018 academic year awards range from $606 to $5,920, which could significantly lower the amount you borrow annually. Your next step is to apply for scholarships. You can start by checking online scholarship search engines, such as the Salt Scholarship Search, College Board's BigFuture and Peterson's. But don't forget to take advantage of local organizations and your school's financial aid office. Both may offer scholarships that you can't find with a national scholarship search. [Review these 10 sites to kick off your scholarship search.]For instance, organizations like the Elks Club, Knights of Columbus or the Rotary Club typically offer scholarships annually to local students. Just because you're going to school online doesn't mean you're ineligible. Visit your local library for scholarship listings, and ask around town. You might be surprised how many local organizations offer scholarships. While these scholarships typically aren't large, every little bit counts. Each dollar you receive in a scholarship is a dollar you don't have to borrow and pay interest on. -- Work-study: Another option for online students may be work-study awards. Not all students enrolled in online programs are eligible, but students at some schools -- including, for example, SUNY Empire State College and Liberty University -- are. Work-study awards are not given upfront like scholarships and grants. In most cases, they are an offer to earn up to the awarded amount if you secure an eligible work-study job. While there is a misconception that all work-study jobs must be on campus, students can work for off-campus, nonprofit or public employers as long as the work is in the public's interest. You may be able to work for a for-profit employer if the job is relevant to your course of study. No matter who the outside employer is, it will need to have an established agreement with your college for you to receive work-study funds. Remember, to be eligible for federal financial aid, you must be enrolled and pursuing a degree or certificate. If you're not working toward a credential, Pell Grants and work-study won't be option, but you may still be able to take advantage of private scholarships -- just be sure to read the eligibility criteria carefully. [Explore what to know about financial aid in online programs.]-- Pay as you go: One of the great benefits to enrolling online is the flexible schedule, which can allow you to complete your college coursework around your responsibilities. But prospective students often overlook using their part- or full-time job earnings as an option for paying for college. Almost 80 percent of college students in 2015 worked at least part time while attending classes, according to the National Center for Education Statistics. By budgeting and thinking strategically about your college costs, you can likely reduce your dependence on student loans by paying a portion out of pocket. Many -- but not all -- online programs are less expensive than traditional programs and often have shorter payment periods. Six, eight or 10 weeks are common course durations. Because of the frequency of payments in an online setting, you may be well-placed to pay as you go and possibly avoid borrowing altogether. Attending college online and avoiding student loans may be challenging, but if you are willing to put in the effort, you can limit the amount you need to borrow. More from U.S. News Q&A: Understanding Student Loan Discharge Eligibility Student Loan Refinancing Isn't Right for All Borrowers
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