Measuring medicine: How new technologies could help doctors predict patient outcomes

EGFR is a therapeutic target in both NSCLC and HNSCC. Patients with NSCLC who present with EGFR mutations are more likely to respond to gefitinib, according to the researchers. However, about 30 percent of patients treated with gefitinib or erlotinib maintain stable disease, defined as no tumor regression and no tumor growth, even without EGFR mutations.

“Most NSCLC patients that develop stable disease with gefitinib or erlotinib therapy do not harbor EGFR mutations,” added co-researcher Pasi A. Jänne, M.D., Ph.D., a second-year fellow at the Dana Farber Cancer Institute. “We have been interested in identifying biomarkers associated with stable disease as this is an important clinical benefit for non-small cell lung cancer patients.”

The presence of amphiregulin varied significantly among the cell lines, ranging from 4.6 to 1,625.8 pg/mL, according to Yonesaka and colleagues. All four EGFR mutant cell lines from the NSCLC samples had negligible levels of amphiregulin. Of note, the researchers detected greater than 250 mg/mL of amphiregulin in seven of the 14 cell lines with wild-type EGFR. These NSCLC and HNSCC cell lines were sensitive to gefitinib and cetuximab. In contrast, cell lines producing less than 250 pg/mL of amphiregulin were resistant to both gefitinib and cetuximab.

Immunohistochemistry of tissue samples revealed that eight of the 10 samples of patients with stable disease following treatment with gefitinib had high amphiregulin expression the researchers report. Only one of 14 samples with high amphiregulin expression was from a patient with progressive disease (P < .001), suggesting that high amphiregulin expression was associated with the development of stable disease with gefitinib or erlotinib treatment, the researchers said.

The detection and prediction of circulating tumor cells in breast cancer patients: Abstract 3696A

Note: This researcher is not scheduled to participate in a press briefing at the meeting. Interviews can be arranged by contacting Staci Goldberg at 267-646-0616.

Researchers report a new, noninvasive method for measuring circulating tumor cells in patients with breast cancer, information which can be used to predict the likelihood that cancer will spread. The technique detects circulating tumor cells with 100 percent specificity and 88 percent sensitivity, researchers report.

“Metastasis, or the spread of cancer beyond the original site, is the main cause of death in breast cancer,” said Tim Molloy, Ph.D., a post-doctoral fellow at the Netherlands Cancer Institute. “If we can improve ways of measuring risk of metastasis, we can more effectively target therapy and manage these patients.”

Specificity is a statistical calculation that measures the likelihood that a negative result will be associated with the absence of disease. Sensitivity measures the likelihood that a positive result will be associated with disease.

Molloy and colleagues used a quantitative polymerase chain reaction-based detection platform that combined genetic information from four accepted tumor markers into a single score. The higher the score, the greater likelihood of circulating tumor cells.