Is your hemoglobin 'trending'?

Aug 03, 2010

Anemia, a common blood disorder characterized by low hemoglobin levels, has long been associated with those suffering from colorectal cancer. But researchers at Tel Aviv University have discovered that, more than a symptom of active disease, low hemoglobin levels can actually indicate a potential for colon cancer years before it's diagnosed.

Graduate student Inbal Goldshtein, who works with Dr. Gabriel Chodick and Dr. Varda Shalev of Tel Aviv University's School of Public Health and Maccabi Healthcare Services' Department of , says that paying close attention to routine blood test results can be an effective screening system for colon cancer which, when diagnosed early enough, can be treated effectively. More than 50,000 people in the U.S. will die from colon cancer in 2010. Better screening could significantly reduce those numbers, Goldshtein says.

The study, recently published in the European Journal of , shows that most patients with colon cancer have a history of consistently declining hemoglobin levels up to four years before being diagnosed with the disease. Previously, says Goldshtein, researchers only looked for a sharp decrease in hemoglobin levels as a symptom of . But Goldshtein and her fellow researchers have discovered that it's the continuous long-term decline that may announce the onset of cancer. A declining trend of more than 0.28 grams per decilitre every six months over a four-year period was observed and may serve as a warning of illness on the horizon.

An important downward trend

Taking into account the correlation between anemia and colorectal cancer, the team was keen to discover if a decline in hemoglobin levels could be detected prior to the critical stages of the disease ― something no researcher had yet attempted to quantify. Over 3,000 patients suffering from colorectal cancer participated in the study; they were compared with 10,000 control cases without colorectal cancer. Goldshtein and her fellow researchers looked at data from each participant's blood tests over a ten-year period, retrieved from the computerized database of Maccabi Healthcare Services.

Though hemoglobin levels may vary in every human being as a result of aging, a distinct trend was discovered among study participants who had been diagnosed with colorectal cancer during the study period. Approximately four years prior to their diagnoses, their blood tests began to show a continuous decline in hemoglobin levels.

For the most part, says Goldshtein, these warning signs went unnoticed. "In practice, a doctor will look at the final results, and see if the hemoglobin levels are within a normal range," she explains. "But this is not accurate enough. It is important to look at the continuing trend of each individual. If a person experiences a consistent decline relative to his own average level, it may be cause for concern."

Participants of the study with colorectal cancer experienced a sharp decline in hemoglobin levels, but because the declines did not put them outside the normal range, no red flags were raised.

A new algorithm for the average physical

The benefit of this screening process is that can be part of an average physical. Current testing for colorectal cancer is often expensive and unpleasant. There is also a very low compliance rate among patients, she adds.

The next step, says Dr. Shalev, is to create an algorithm which will automatically detect suspicious declines in hemoglobin levels, advising physicians to send their patients for further testing. Ideally, she notes, the Tel Aviv University team will develop a computer program that will display warnings when there is cause for concern.

Explore further: Genomic analysis of prostate cancer indicates best course of action after surgery

add to favorites email to friend print save as pdf

Related Stories

High vitamin D levels linked to lower risk of colon cancer

Jan 21, 2010

High blood levels of vitamin D are associated with a lower risk of colon cancer, finds a large European study published on bmj.com today. The risk was cut by as much as 40% in people with the highest levels compared with ...

Study links vitamin D to colon cancer survival

Jun 19, 2008

Patients diagnosed with colon cancer who had abundant vitamin D in their blood were less likely to die during a follow-up period than those who were deficient in the vitamin, according to a new study by scientists at Dana-Farber ...

Recommended for you

Cancer: Tumors absorb sugar for mobility

8 hours ago

Cancer cells are gluttons. We have long known that they monopolize large amounts of sugar. More recently, it became clear that some tumor cells are also characterized by a series of features such as mobility or unlikeliness ...

Early hormone therapy may be safe for women's hearts

17 hours ago

(HealthDay)—Healthy women at low risk of cardiovascular disease may be able to take hormone replacement therapy soon after menopause for a short time without harming their hearts, according to a new study.

Low yield for repeat colonoscopy in some patients

18 hours ago

(HealthDay)—Repeat colonoscopies within 10 years are of little benefit to patients who had no polyps found on adequate examination; however, repeat colonoscopies do benefit patients when the baseline examination was compromised, ...

User comments : 0