Surgery compared to non-surgical treatment to relieve symptoms of bowel obstruction in ovarian cancer

Ovarian cancer is the sixth most common cancer among women and is usually diagnosed at an advanced stage. Bowel obstruction is a common feature of advanced or recurrent ovarian cancer and causes vomiting, pain and diarrhoea. Patients with bowel obstruction are generally in poor physical condition with only a short time left to live. Therefore, maintaining their QoL with effective symptom control is the main purpose of the management of bowel obstruction.

We carried out a systematic review of published and unpublished studies that compared surgical and non-surgical methods of managing bowel obstruction in women with ovarian cancer.

Women who are recommended for surgery are usually in better health than those who are not, so it can be difficult to disentangle the effects of surgery and the effects of their basic health.   Therefore we only looked at studies that used statistical adjustment for the differences in underlying health between women who did and did not receive surgery.

We found only one relevant study. It included only 47 cases: 27 had an operation to relieve bowel obstruction and the 20 who did not have an operation were given a drug called Octreotide to control the amount of vomiting that often results from bowel obstruction.

Among the 27 women who had an operation, six women could not have their bowel obstruction corrected because the cancer had spread too far, six women had serious complications of surgery and three died of these complications.  Nevertheless, the authors of the study reported that women who had the operation survived longer, on average, than those who did not, even after allowing for their underlying better health. It was unclear how much of the difference in survival could be ascribed to the differences in treatment and how much to the better health of women undergoing surgery.

Unfortunately the study did not assess their QoL or level of pain. 

The study reported the numbers of women who could start eating again after their treatment (surgery or Octreotide) but it didn't analyse this allowing for the underlying difference in health of women in the two groups, so it is impossible to interpret these results.

We were therefore unable to reach definite conclusions about the relative benefits and harms of the two forms of treatment and we were unable to identify sub-groups of women who are likely to benefit from one treatment or the other.

Authors' conclusions: 

We found only low quality evidence comparing palliative surgery and medical management for bowel obstruction in ovarian cancer. Therefore we are unable to reach definite conclusions about the relative benefits and harms of the two forms of treatment, or to identify sub-groups of women who are likely to benefit from one treatment or the other. However, there is weak evidence in support of surgical management to prolong survival.

Read the full abstract...
Background: 

Ovarian cancer is the sixth most common cancer among women and is usually diagnosed at an advanced stage. Bowel obstruction is a common feature of advanced or recurrent ovarian cancer. Patients with bowel obstruction are generally in poor physical condition with a limited life expectancy. Therefore, maintaining their QoL with effective symptom control is the main purpose of the management of bowel obstruction.

Objectives: 

To compare the effectiveness and safety of palliative surgery (surgery performed to control the cancer, reduce symptoms and improve quality of life for those whose cancer is not able to be entirely removed) and medical management for bowel obstruction in women with ovarian cancer.

Search strategy: 

We searched the Cochrane Gynaecological Cancer Group Trials Register, The Cochrane Central Register of Controlled trials (CENTRAL), Issue 1 2009, MEDLINE and EMBASE up to February 2009. We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included studies and contacted experts in the field.

Selection criteria: 

Studies that compared palliative surgery and medical interventions, in adult women diagnosed with ovarian cancer who had either full or partial obstruction of the bowel. Randomised controlled trials (RCTs) and non-RCTs that used multivariable statistical adjustment for baseline case mix were eligible.

Data collection and analysis: 

Two review authors independently assessed whether potentially relevant studies met the inclusion criteria, abstracted data and assessed risk of bias. One non-randomised study was identified so no meta-analyses were performed.

Main results: 

The search strategy identified 183 unique references of which 22 were identified as being potentially eligible on the basis of title and abstract. Only one study met our inclusion criteria and was included in the review. It analysed retrospective data for 47 women who received either palliative surgery (n = 27) or medical management with Octreotide (n = 20) and reported overall survival and perioperative mortality and morbidity. Women with poor performance status were excluded from surgery. Although six (22%) women who received surgery had serious complications of the operation and three (11%) died of complications, multivariable analysis found that women who received surgery had significantly (p < 0.001) better survival than women who received Octreotide, after adjustment for important prognostic factors. However, the magnitude of this effect was not reported. Quality of life (QoL) was not reported and adverse events were incompletely documented.