FRIDAY, July 3 (HealthDay News) -- The new vaccine vitespen didn't increase recurrence-free survival among kidney cancer patients who'd had surgery, say U.S. researchers.

Surgery is standard treatment for kidney cancer, but many patients are at risk of cancer recurrence because there is no effective adjuvant treatment, according to background information in the study by Dr. Christopher Wood, of the M.D. Anderson Cancer Center in Houston, and colleagues.

For this study, 818 kidney cancer patients who'd had surgery were divided into two groups. One group (409) received vitespen once a week for four weeks, then every two weeks until vaccine depletion. The other 409 patients were kept under observation.

The final analysis of 361 patients in the vitespen group and 367 patients in the observation group found no significant difference in recurrence-free survival. But an analysis of a subgroup of patients with early-stage kidney cancer showed a 15.2 percent rate of recurrence among those who received vitespen and a 27 percent rate of recurrence among patients kept under observation.

While this wasn't a statistically significant difference, the researchers said the improvement in recurrence-free survival among patients with early-stage cancer who received the vaccine warrants further investigation.

The study was published online this week in The Lancet.

In an accompanying comment, Dr. James Yang, of U.S. National Cancer Institute, noted that the manufacturers of vitespen have focused on one possible positive outcome of this study, rather than the overall negative results.

"Such practices are akin to shooting the arrow first and being permitted to draw the target afterwards," he wrote.

The field of cancer immunotherapy is weakened when some researchers and vaccine companies are reluctant to accept the results of randomized clinical trials, Yang said.

"Commercially driven efforts that spin or obfuscate the conclusions of such a trial should be vigorously resisted because such efforts severely erode its value," he concluded.

More information

The American Cancer Society has more about kidney cancer.