Neuroblastoma Screening Evaluation Hailed as Model of Health Assessment

A Canadian study, which demonstrated the ineffectiveness of neuroblastoma screening of newborns, was cited as a "well-designed evaluation" of a proposed health care intervention strategy in an analysis published in the August 3 Journal of the National Cancer Institute (JNCI).

The Quebec Neuroblastoma Screening Project (QNSP) was designed to test the benefits and costs of such screening before it was widely adopted in North America. About 92 percent of babies born in Quebec between 1989 and 1994 were screened during the study. In 2002, QNSP researchers reported that the testing did not reduce mortality from the disease, and that the unnecessary testing and treatment also caused adverse health effects. Those findings led to the abandonment of plans for widespread neuroblastoma screening in the United States and Canada, and also caused Japan to end its already established screening program.

In the new analysis, researchers - led by Dr. Lee Soderstrom of McGill University in Montreal - compared the $8.8 million cost of the QNSP against the estimated costs if neuroblastoma screening had been implemented in North America. In addition to the projected $574 million savings in health care costs, the investigators estimated there would have been unnecessary treatment of 9,223 children and false-positive findings for 5,003 children screened.

New-Onset Diabetes Is Possible Marker for Early Pancreatic Cancer

A population-based study showed that a diagnosis of new-onset diabetes in older patients could serve as a marker for identifying individuals with early stage pancreatic cancer, according to the August 1 Gastroenterology.

Researchers at the Mayo Clinic College of Medicine reviewed data from a cohort of 2,122 Rochester, Minn., patients diagnosed with diabetes at age 50 and older between 1950 and 1994. Of that study group, 18 patients (0.85 percent) were diagnosed with pancreatic cancer within 3 years of meeting criteria for diabetes. "This translates to a 3-year risk of pancreatic cancer of nearly 8 times higher than that for a person of similar age and sex in the general population," reported the scientists, led by Dr. Suresh T. Chari.

Pancreatic cancer is usually diagnosed at later stages when clinical symptoms first appear and prognosis is very poor. "In this study, we highlight the potential for utilizing hyperglycemia and diabetes to define a population at high risk for having pancreatic cancer," the researchers noted. This may enable screening and detection of the disease in earlier stages when it can be more effectively treated.

Further studies are needed to prove the usefulness of new-onset diabetes as a marker, the researchers caution, given the rarity of pancreatic cancer and the common prevalence of diabetes among older individuals.

Revised TNM Classification System Predicts Breast Cancer Survival

A revised staging system for breast cancer, which relies only on pathology reports to classify residual disease in both the breast and axillary lymph nodes after neoadjuvant chemotherapy, provides a superior way to predict distant relapse and overall survival, according to a study in the August 3 JNCI.

Investigators from the University of North Carolina at Chapel Hill applied the American Joint Committee on Cancer tumor-node-metastasis (TNM) staging system to 132 nonmetastatic breast cancer patients who received chemotherapy before surgery in 2 different trials that occurred between 1992 and 2000.

The trials differed in the regimen of neoadjuvant drugs: 64 percent of patients received anthracycline-based chemotherapy, while 36 percent received the same regimen with the addition of taxane. All patients underwent surgery and then received a wide array of follow-up treatments. They were followed for a median of 5 years. Despite the many treatment variables, the researchers found that the TNM classifications were highly predictive of patients' 5-year morbidity and mortality rates.

The researchers compared the TNM system favorably against several other breast cancer staging methods in terms of accuracy and ease of use. TNM also was found to be "simple and reproducible," and much more useful as an intermediate endpoint than pathological complete response, which occurs infrequently.

Myeloid Leukemia Linked to Body Size

The risk of myeloid leukemia is associated with body size and composition, according to a study in the August 3 JNCI.

The Melbourne Collaborative Cohort Study involved 40,909 people in Australia, and explored the correlation between nutritional and lifestyle choices and cancer. Beginning in 1990, participants between the ages of 27 and 75 were followed for an average of 8.4 years. Height, weight, and waist and hip circumferences were measured and used to compute body mass index (BMI), waist-to-hip ratios, fat mass, and percent fat. The researchers also collected information on country of birth, alcohol consumption, smoking, physical activity, and education level.

The report found that myeloid leukemia is linked to several components of body size. Overweight and obese persons (those with a BMI of at least 25 and 30, respectively) were 5 times more likely to have myeloid leukemia than those with BMIs lower than 25. Waist circumference was related to increased risk as well. Stature was not linked to myeloid leukemia incidence; however, people with a higher non-fat component of weight or central adiposity were at an increased risk.

Conversely, other lymphohematopoietic malignancies - including non-Hodgkin's lymphoma, multiple myeloma, and lymphocytic leukemia - showed little relation to body size. However, lead author Dr. Graham G. Giles noted that past research on these relationships has been minimal, and some reports have found obese people at increased risk for these diseases, so whether an association exists remains unclear.