Highlights From the 2008 Meeting of the American Society for Clinical Oncology

The 44th Annual Meeting of the American Society of Clinical Oncology, held May 30th to June 2nd, brought more than 30,000 attendees to Chicago for the presentation of nearly 5,000 new studies. The following research findings represent a few of the highlights, as announced by ASCO before the meeting.

Vitamin D and Breast Cancer: Canadian researchers have found for the first time that women with vitamin D deficiency at the time of breast cancer diagnosis were 94% more likely to experience metastasis of their cancer and 73% more likely to die, compared to women with adequate vitamin D levels. They also found that more than a third (37.5%) of women with breast cancer had vitamin D levels that were classified as deficient (abstract 511).

“Our results need to be replicated,” cautioned lead author Pamela Goodwin, md, professor of medicine at the University of Toronto. “These data indicate an association between vitamin D and breast cancer outcome, but we can’t say at this time if it is causal.”

Rise in Mastectomies for Early Breast Cancer: Mayo Clinic researchers have reported that the number of mastectomies performed at Mayo Clinic Rochester (Minnesota) increased 13% in 3 years: mastectomy accounted for 43% of early-stage breast cancer surgeries in 2006, up from 30% in 2003. Women who received breast magnetic resonance imaging (MRI) before surgery were significantly more likely to undergo mastectomy than those who did not, although the rise in mastectomy rates was observed in both groups (abstract 509).

Preoperative breast MRI may find cancer in more than one part of the breast, which may lead physicians and patients to choose mastectomy more often than lumpectomy, noted Rajini Katipamula, md, senior clinical fellow in hematology/oncology at Mayo Clinic and the study’s lead author.

Heart Disease in Childhood Cancer Survivors: Survivors of childhood cancers are 5 to 10 times more likely than their healthy siblings to develop heart disease in early adulthood, according to findings from the Childhood Cancer Survivor Study (abstract 9509).

“This study shows that childhood cancer survivors in their 20s are developing the kinds of heart disease we typically see in older adults,” explained lead author Daniel A. Mulrooney, md, assistant professor of pediatrics at the University of Minnesota. “Our findings emphasize the need to educate patients, their families, and other health-care providers about the risk of delayed cardiovascular side effects of these otherwise life-saving cancer treatments.”

Pemetrexed Maintenance for Lung Cancer: A new study has shown that maintenance therapy with pemetrexed (Alimta) delays by 50% the time it takes for advanced non–small-cell lung cancer (NSCLC) to progress. Maintenance therapy is given 3 to 6 weeks after completing platinum-based induction chemotherapy (abstract 8011).

“This is the first study to show that lung cancer patients can benefit from maintenance therapy. The fact that this approach significantly increases the amount of time that patients have before their cancer progresses, without increasing additional side effects, is particularly significant,” said lead author Tudor Eliade Ciuleanu, md, phd, associate professor at the University of Medicine and Pharmacy Iuliu Hatieganu in Romania. “We recommend giving pemetrexed after a patient completes initial induction therapy, but before cancer progression occurs.”

More Frequent Chemotherapy for Ewing’s Sarcoma: Investigators from the Children’s Oncology Group have found for the first time that giving combination chemotherapy (vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide) every 2 weeks is more effective than the same therapy given every 3 weeks in patients with Ewing’s sarcoma, without increasing side effects (abstract 10504).

“These findings are convincing enough to change the standard of care for patients with localized Ewing’s sarcoma,” said lead author Richard B. Womer, md, senior oncologist and professor of pediatrics at the University of Pennsylvania School of Medicine.

Predictive Gene Signature in Lung Cancer Patients: Canadian researchers have identified a set of 15 genes that may predict the aggressiveness of early-stage NSCLC and identify those patients who might benefit most from chemotherapy after surgery. The preliminary findings suggest that this gene-expression signature could spare patients with less aggressive cancer from chemotherapy and its side effects (abstract 7510).

“Not all patients benefit from chemotherapy and not all patients require chemotherapy after surgery,” said lead author Ming Tsao, MD, professor of laboratory medicine and pathobiology at the University of Toronto.