Chemotherapy and Twice-Daily Radiation Improves Small Cell Lung Cancer Survival
Of the roughly 170,000 cases of lung cancer diagnosed in the United States each year, 20 percent are small cell cancers. Prior studies have shown that radiation therapy (radiotherapy) in addition to chemotherapy improves survival in people with limited small cell lung cancer -- disease confined to one side of the chest. However, the best way to combine and administer these treatments has been unclear.
A multicenter study published January 1999 in the New England Journal of Medicine (see the journal abstract) tackled the issue by holding chemotherapy constant and comparing two- and five-year survival results between patients who received either once- or twice-daily doses of chest radiation (both groups received the same cumulative total dose of radiation).
All patients studied received four 21-day chemotherapy cycles of cisplatin plus etoposide. The report's authors say this drug combination is the primary chemotherapy for small cell lung cancer and when used with radiation causes less toxicity than other drug regimens.
"Survival was significantly better in the group receiving twice-daily radiotherapy (over three weeks) than in the group receiving once-daily radiotherapy (over five weeks)," the authors note.
Moreover, in terms of overall survival, the rate among the 417 patients studied "exceeded that in any previously reported large, randomized trial of chemotherapy and radiotherapy for this disease," the authors state.
The survival rates for patients receiving once-daily radiotherapy were 41 percent at two years and 16 percent at five years. For patients receiving twice-daily radiotherapy, the survival rates 47 percent at two years and 26 percent at five years.
A "moderate" radiation dose of 45 Gy helped reduce irreversible injury to the esophagus. Still, rates of toxicity to the esophagus resulting in difficulty swallowing solids, need for narcotic pain killers, or use of feeding tube were more than double in the twice-daily radiotherapy group (27 percent versus 11 percent). However, all patients affected by esophagitis recovered their ability to swallow. |
