Follow-up surgery to remove all traces of cancer can improve the survival of women whose ovarian cancer returned after initial surgery and chemotherapy, a Norwegian study shows.
In the study, researchers found that a secondary surgery delayed the reappearance of new cancer for two years. The median overall survival rate for these patients was at least six years.
The study, “Survival after secondary cytoreductive surgery and chemotherapy compared with chemotherapy alone for first recurrence in patients with platinum‐sensitive epithelial ovarian cancer and no residuals after primary treatment. A registry‐based study,” was published in the journal Acta Obstetricia et Gynecologica Scandinavica.
Primary treatment of women with epithelial ovarian cancer typically consists of cytoreductive surgery to remove as many tumor cells as possible, followed by chemotherapy cycles.
Although the disappearance of all signs of cancer, called complete remission, is obtained for a large number of patients, in some cases, cancer can return. This may happen even in patients whose first surgery completely removed all traces of a tumor.
When a relapse occurs more than six months after the end of the primary treatment, platinum-based chemotherapy is generally the treatment of choice.
But prior studies and clinical trials, such as DESKTOP II (NCT00368420), have indicated that a second surgery to remove all signs of a recurrent tumor can improve patient survival.
In Norway, a second surgery may be offered to women with recurrent epithelial ovarian cancer with localized tumors, and in some cases, to women whose cancer has spread to other tissues.
In this study, a team of Norwegian researchers conducted a retrospective analysis to better understand the clinical benefits of having a second surgery. Another goal was to identify potential predictors of survival that could indicate which women would most benefit from having the surgery.
Using data from the Cancer Registry of Norway, researchers compared the survival of 75 women who received a second cytoreductive surgery followed by platinum-based chemotherapy with 322 who received platinum-based chemotherapy alone.
Only women whose first surgery removed all traces of cancer, who were fully active, and who presented no fluid in the abdomen were included.
Having a second surgery doubled the median time to disease worsening or death, called progression-free survival, from one year to two years.
In terms of overall survival, the benefit of a second surgery also was clear. The median overall survival rate in the group that had surgery was six years. For the group that took platinum-based chemotherapy only, it was two years.
Women who had a second surgery were twice as likely of surviving than those who did not, researchers said.
Importantly, a survival benefit was only seen for women whose second surgery removed all signs of the tumor, known as complete resection, which happened in 80 percent of all those who had the surgery.
If looking only at these patients, the likelihood of surviving was nearly three times longer than those in the group that did not have surgery.
The benefit was higher in women who had complete removal of a tumor and whose cancer was not widespread (with three or fewer lesions on radiograms). These women had a five-year survival rate of 77 percent, compared to 40 percent in the group of women that did not receive a second surgery.
Another important observation was that women who had a longer period without having the first cancer recurrence, known as treatment-free interval, had significantly higher progression-free and overall survival rates.
The results confirm prior observations showing that in select women with no cancer traces after the first surgery, a second surgery for complete removal of the recurrent tumor significantly increases their survival.
Additionally, researchers noted that “long treatment-free interval and non-disseminated lesions (three or fewer lesions) on radiological images could be useful predictors for complete resection at secondary cytoreductive surgery.”
Together with this study, two ongoing clinical trials evaluating the effect of a second surgery (DESKTOP III, NCT01166737, and NCT00565851) are expected to contribute important information to help improve recommended guidelines and the treatment of patients with recurrent ovarian cancer.