• Hormone replacement therapy reduces risk of colon cancer.
• Smoking before age 30 increases chances that colon cancer will recur.
• Low CEA levels improve both survival and disease-free survival for stage II colon cancer.
• Most patients want videos of their colonoscopies and are willing to pay for them.

Use of hormone replacement therapy reduces colon cancer

Women in a study of California teachers who were taking hormone replacement therapy (HRT) after menopause had a 36 percent reduced risk of colon cancer over ten years than women who weren’t on HRT at the beginning of the study.  Risk reduction was even greater for women with a first-degree relative who had colon cancer.  Their risk fell 55 percent.

Over 57,000 women were part of the study, about 60 percent of them on HRT at the study start.  Over the next ten years, 444 got colon cancer.

Despite the reduction in colon cancer in the study, doctors caution women about using HRT because of raised risks for breast cancer, heart attack, stroke, and blood clots.  Advice is to use the lowest dose for the shortest time to offset severe menopausal symptoms.

Katherine DeLellis Henderson, PhD, reports the study results in the February 15, 2010 issue of the American Journal of Epidemiology.

Early smoking history reduces disease-free survival after colon cancer

Patients with stage III colon cancer who had a smoking history of 12 or more pack years before they were 30 had almost a 40 percent increased risk of having their cancer return within three years compared to patients who had never smoked.

Among the 1,045 study participants, 46 percent had never smoked, 44 percent were past smokers, and 10 percent were currently smoking.

Disease-free survival three years after treatment was about 18 percent greater for people who had never smoked than for past smokers.

The results, based on questionnaires filled out by patients in the CALGB 80893 adjuvant chemotherapy trial, were published by Nadine Jackson McCleary, MD, MPH,and her colleagues in Cancer, February 15, 2010. They wrote,

Total tobacco usage early in life may be an important, independent prognostic factor of cancer recurrences and mortality in patients with stage III colon cancer.

CEA levels before surgery important for stage II prognosis

Patients whose CEA (carcinoembryonic antigen) blood levels before surgery were low — below 5 ng/ml — had significantly better overall and disease free survival than those whose CEA’s were 5 or higher.  For those with low CEA, overall survival at five years was 81.7 percent compared to 69.9 percent for high CEA.  Disease-free survival was 82.4 percent for low CEA and 70.6 percent for CEA that was 5 ng/ml or higher.

However, CEA levels only made a difference in stage II patients.  There was no significance for stage I or III.

Writing in the Journal of Surgical Oncology, Korean surgeon Jung Wook Huh, MD and colleagues concluded,

Preoperative serum CEA is a reliable predictor of recurrence and survival after curative surgery in patients with colon cancer, particularly in those classified as having stage II disease.

Patients want videos of their colonoscopies

Eight out of ten patients having colonoscopies said that they would like to have a video recording of their colonoscopy, and more than 6 of 10 (63 percent) were willing to pay for it.  After reading a brief paragraph explaining missed lesions during colonoscopy, over half (54 percent) were more interested in a video and none were less interested.

Meghana Raghavendra surveyed 248 outpatients at the Indiana University School of Medicine and reported the results in the World Journal of Gastroenterology, in an early online article January 28, 2010.

Compared to patients with consistently rising carcinoembryonic antigen (CEA), patients who had a CEA flare had more tumor shrinkage, longer time before their cancer got worse, and longer survival time.

Researchers measured CEA before chemotherapy started and at least twice during chemo in patients with advanced colorectal cancer who were receiving their first course of chemotherapy.

They grouped patients according to how the CEA measurements changed over time:

• flare
  
• decreasing CEA
• normal baseline CEA
• stable CEA
• increasing CEA

Comparing patients with increasing CEA measurements to patients whose CEA rose and then fell (flared):

• Overall response rate was 11 percent in increasing CEAs compared to 73 percent in flares.
• Progression-free survival time was 3.1 months compared to 8.3 months with flares.
• Overall survival was 10.9 months compared to 17.7 months when CEA flared.

A. S. Strimpakos and colleagues at the Royal Marsden Hospital in London concluded,

Compared with patients with rising CEA, flare was an independent favourable predictive and prognostic factor for tumour response and survival.

More information on the CEA flare during first-line chemotherapy  is available from Dr. Strimpakos’ poster presented at the 2009 GI Symposium.

SOURCE: Strimpakos et al., Annals of Oncology, Advance Access, October 27, 2009.

While overall patients with stage I or IIA colon cancer (early stage) have a lower risk of cancer returning than patients with stage IIB or III (later stage), careful surveillance after surgery is as effective in finding and treating cancer in both groups.

About one in three patients in both the early and late stage who had a recurrence detected during surveillance were able to have surgery with the goal of curing their cancer.  

Using information from the Clinical Outcomes of Surgical Therapy (COST) study, researchers divided 872 patients without metastatic colon cancer into two categories:

• Early stage disease: stages I or IIA
• Late stage disease: stages IIB and III

All patients in the study, no matter their stage at diagnosis, followed the same surveillance plan after surgery.

• History and physical exam every 3 months for 1 year then every 6 months to 5 years
• Carcinoembryonic antigen (CEA) blood test every 3 months for 1 year then every 6 months to 5 years
• Chest x-ray every 6 months for 2 years then every 1 year to 5 years
• Annual colonoscopy if positive for polyps or cancer; exam every 3 years if first one was negative
• CT scan of abdomen at discretion of physician for symptoms, signs, or increased CEA

Results found:

• By five years, about 1 in 10 early stage patients had a recurrence of their cancer (9.5 percent) compared to about 1 in 3 late stage patients (35.7 percent).
• Sites where cancer had spread were similar in both groups, although late stage patients were more likely to have spread to more than one site.
• Median survival after surgery for recurrence, when possible, was 51.2 months for early stage and 35.8 months for late stage patients.

There was little difference between groups  in how the recurrence was initially found:

• Elevated carcinoembryonic antigen (CEA) test found 29 percent of early versus 37 percent of late stage recurrent cancers and was the most common way of finding recurrences, particularly in the second year when it found more recurrences than CT-scan, chest x-ray, and colonoscopy combined.
• CT-scans uncovered 24 percent of early versus 26 percent of late stage recurrences.
• Chest x-rays found 7 percent of early versus 12 percent of late stage recurrence.
• Colonoscopy found 13 percent of early versus 9 percent of late ones.

Of the entire group of 537 patients with an early stage diagnosis (stage I and IIA), 55 had a recurrence.  20 of them went on to a second surgery and had a median survival of 51 months after their operation.  Those for whom surgery wasn’t possible had a much shorter survival of about 9 months.

There were 254 patients initially diagnosed as late stage (stage IIB and III).  Of those, 91 experienced a recurrence and 32 were able to have a second surgery.  Like the early stage patients, a second surgery led to much longer survival — 36 months versus 11 months without surgery.

Vassiliki L. Tsikitis and the study team concluded,

Patients with early-stage colon cancer have similar sites of recurrence, and receive similar benefit from postrecurrence therapy as late-stage patients; implementation of surveillance guidelines for early-stage patients is appropriate.

SOURCE: Tsikitis et al., Journal of Clinical Oncology, Volume 27, Number 22, August 1, 2009.