Since Medicare approved coverage for screening colonoscopies, there has been

• a significant increase in the rate of colonoscopies in the Medicare population
• an increased possibility of being diagnosed with colorectal cancer at an early, highly curable stage I

Medicare began to provide reimbursement for people at high risk of colorectal cancer in 1998 and expanded coverage to everyone on Medicare in July of 2001. 

Researchers at the Yale University School of Medicine reviewed SEER (Surveillance, Epidemiology, and End Results) information for patients diagnosed with colon cancer between 1992 and 2002.  They also looked at a group of Medicare-eligible patients in the database who did not have colon cancer.  They examined rates of colonoscopy screening and stage at diagnosis for three periods of time:

• Period 1 –  no coverage (1992 to 1997)
• Period 2 — limited coverage (January 1998 – June 2001)
• Period 3 — full coverage (July 2001 – December 2002)

They found increasing rates of colonoscopy screening for people eligible for Medicare.  Rates tripled between the period when there was no coverage  and doubled again when reimbursement was extended to all patients.

• Period 1 — 285 colonoscopies/100,000 eligible people
• Period 2 –  889/100,000
• Period 3 — 1919/100,000

Separating people diagnosed with colon cancer into two groups:  early stage (stage 1) and all other stages (stages II-IV), they found an increasing percentage of patients diagnosed at an early stage.

• Period 1 — 22.5% of cancers were found at an early stage
• Period 2 — 25.5%
• Period 3 — 26.3%

The strongest association with early diagnosis was found in patients whose cancers were in the proximal colon (the first section of colon farthest from the rectum).  There was a very small association for distal tumors on the left side of the body.

Dr. Cary Gross and colleagues reported their results in the December 20, 2006 issue of the Journal of the American Medical Association.  They concluded,

Expansion of Medicare reimbursement to cover colon cancer screening was associated with an increased use of colonoscopy for Medicare beneficiaries, and for those who were diagnosed with colon cancer, an increased probability of being diagnosed at an early stage. The selective effect of the coverage change on proximal colon lesions suggests that increased use of whole-colon screening modalities such as colonoscopy may have played a pivotal role.

Gross et. al. JAMA. 2006;296:2815-2822

The Centers for Disease Control (CDC) has a fact sheet on colorectal cancer screening for people receiving Medicare.

People Living with Cancer (PLWC) has published a new bulletin for December 2006.

Besides links to current cancer news, the PLWC Bulletin includes additions to the Patients Toolbox.  Of particular interest to people affect by colorectal cancer are:

• Colonoscopy — What to Expect
• Biopsy — What to Expect
• A listing of Telephone and E-Mail Cancer Helplines
• An updated article on Obesity and Cancer

Reader’s questions will be answered through December 31 in the Ask the Experts Series.  This month’s focus is Tips to Cope with Cancer Treatment.

The December Bulletin also has a link to the American Society of Clinical Oncology (ASCO) Clinical Care Advances 2006.

Radiologists at M.D. Anderson Cancer Center in Texas have found that conformal radiotherapy (CRT) to the largest (dominant) liver metastasis can control cancer progression for several months. 

Reviewing records of 17 patients with colorectal cancer that had spread to the liver and who were treated with conformal radiotherapy, they found median time to progression after treatment were:

• 6.8 months for the tumor that was radiated
• 3.1 months for tumors in the liver outside the field of radiation
• 4.1 months for tumors outside of the liver

Dominant liver tumors had a median size of 10 centimeters, and 71% of patients had evidence of cancer outside the liver.  Surgical resection was impossible.  In addition, patients had already received a median of 2 chemotherapy regimens.

Overall survival time after radiotherapy was 12.6 months.

Most patients were also receiving chemotherapy including celecoxib (Celebrex®) and capecitabine (Xeloda®).

Side effects included diarrhea, nausea, vomiting, fatigue, hand-foot syndrome, and low white cell counts — none of which were severe.

The researchers, who reported their study in the December 2006 issue of the American Journal of Clinical Oncology concluded:

Conformal RT to the dominant liver metastasis as palliative therapy for unresectable colorectal cancer liver metastases has an acceptable toxicity profile and may improve survival. This approach merits further exploration.

In a group of 300 Munich patients who underwent both CT colonography (virtual colonoscopy) and optical colonoscopy on the same day, CT colonography was both sensitive and specific in finding polyps. 

Dividing the adenomas into three groups — small polyps under 5 mm, intermediate 6 mm to 9 mm, and large 10 mm and over–,  the radiologists found sensitivity and specificity of:

• 96% and 100% for large polyps
• 92% and 96.7% for intermediate
• 78.9 and 89.5% for small

Optical colonoscopy missed one large, two intermediate, and eight small polyps for sensitivities of 96%, 95%, and 89.5%.

Dr. Anno Graser, a radiologist at the University of Munich, presented the results at the 2006 meeting of the Radiological Society of North America (RSNA) on November 28. The study is part of the Munich Colorectal Cancer Prevention Trial.

The researchers cautioned that while CT colonography is highly accurate in finding polyps, there is more of a problem in finding flat lesions, a difficulty shared with optical colonoscopy.

Dr. Graser also presented a new 3-dimensional CT technique that provides a panoramic view of the colon and requires only one passage of the scanner from rectum to colon rather than a two-directional one.  The technique decreased the time necessary for the test without sacrificing accuracy

The FDA approved the first generic version of injectable ondansetron on November 22, 2006.  Previously ondansetron was only available as the brand-name drug Zofran®.

Ondansetron is indicated to prevent nausea and vomiting during chemotherapy and to prevent nausea and vomiting after surgery

Approval is for injectable ondansetron manufactured by TEVA Pharmaceuticals and premixed ondansetron injections manufactured by SICOR Pharmaceuticals.

Gary J. Buehler, Director of the FDA Office of Generic Drugs, said,

These approvals will result in significant savings for the American public. Generic drugs undergo a thorough scientific and regulatory review, and are safe and effective alternatives to brand name drugs.