Pentoxifylline versus medical therapies for subfertile women with endometriosis

Pentoxifylline for the treatment of endometriosis-associated pain and infertility

BACKGROUND

Endometriosis is a chronic inflammatory condition that occurs during the reproductive years. It is characterised by endometrium-like tissue developing outside the uterine cavity. This endometriotic tissue development is dependent on oestrogen produced primarily by the ovaries and partially by the endometriotic tissue itself, therefore traditional management has focused on ovarian suppression. In this review we considered the role of modulation of the immune system as an alternative approach. This is an update of a Cochrane Review previously published in 2012.

OBJECTIVES

To determine the effectiveness and safety of pentoxifylline in the management of endometriosis.  SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility (CGF) Group Trials Register, CENTRAL, MEDLINE, Embase, PsycINFO, and AMED on 16 December 2020, together with reference checking and contact with study authors and experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing pentoxifylline with placebo or no treatment, other medical treatment, or surgery in women with endometriosis. The primary outcomes were live birth rate and overall pain (as measured by a visual analogue scale (VAS) of pain, other validated scales, or dichotomous outcomes) per woman randomised. Secondary outcomes included clinical pregnancy rate, miscarriage rate, rate of recurrence, and adverse events resulting from the pentoxifylline intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies against the inclusion criteria, extracted data, and assessed risk of bias, consulting a third review author where required. We contacted study authors as needed. We analysed dichotomous outcomes using Mantel-Haenszel risk ratios (RRs), 95% confidence intervals (CIs), and a fixed-effect model. For small numbers of events, we used a Peto odds ratio (OR) with 95% CI instead. We analysed continuous outcomes using the mean difference (MD) between groups presented with 95% CIs. We used the I2 statistic to evaluate heterogeneity amongst studies. We employed the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

We included five parallel-design RCTs involving a total of 415 women. We included one additional RCT in this update. Three studies did not specify details relating to allocation concealment, and two studies were not blinded. There were also considerable loss to follow-up, with four studies not conducting intention-to-treat analysis. We judged the quality of the evidence as very low. Pentoxifylline versus placebo No trials reported on our primary outcomes of live birth rate and overall pain. We are uncertain as to whether pentoxifylline treatment affects clinical pregnancy rate when compared to placebo (RR 1.38, 95% CI 0.91 to 2.10; 3 RCTs, n = 285; I2 = 0%; very low-quality evidence). The evidence suggests that if the clinical pregnancy rate with placebo is estimated to be 20%, then the rate with pentoxifylline is estimated as between 18% and 43%. We are also uncertain as to whether pentoxifylline affects the recurrence rate of endometriosis (RR 0.84, 95% CI 0.30 to 2.36; 1 RCT, n = 121; very low-quality evidence) or miscarriage rate (Peto OR 1.99, 95% CI 0.20 to 19.37; 2 RCTs, n = 164; I2 = 0%; very low-quality evidence). No trials reported on the effect of pentoxifylline on improvement of endometriosis-related symptoms other than pain or adverse events. Pentoxifylline versus no treatment No trials reported on live birth rate. We are uncertain as to whether pentoxifylline treatment affects overall pain when compared to no treatment at one month (MD -0.36, 95% CI -2.12 to 1.40; 1 RCT, n = 34; very low-quality evidence), two months (MD -1.25, 95% CI  -2.67 to 0.17; 1 RCT, n = 34; very low-quality evidence), or three months (MD -1.60, 95% CI -3.32 to 0.12; 1 RCT, n = 34; very low-quality evidence). No trials reported on adverse events caused by pentoxifylline or any of our other secondary outcomes. Pentoxifylline versus other medical therapies One study (n = 83) compared pentoxifylline to the combined oral contraceptive pill after laparoscopic surgery to treat endometriosis, but could not be included in the meta-analysis as it was unclear if the data were presented as +/- standard deviation and what the duration of treatment was. No trials reported on adverse events caused by pentoxifylline or any of our other secondary outcomes. Pentoxifylline versus conservative surgical treatment  No study reported on this comparison.

AUTHORS' CONCLUSIONS

No studies reported on our primary outcome of live birth rate. Due to the very limited evidence, we are uncertain of the effects of pentoxifylline on clinical pregnancy rate, miscarriage rate, or overall pain. There is currently insufficient evidence to support the use of pentoxifylline in the management of women with endometriosis with respect to subfertility and pain relief outcomes.

Pre- and postsurgical medical therapy for endometriosis surgery

BACKGROUND

Endometriosis is a common gynaecological condition affecting 10% to 15% of reproductive-age women and may cause dyspareunia, dysmenorrhoea, and infertility. One treatment strategy is combining surgery and medical therapy to reduce the recurrence of endometriosis. Though the combination of surgery and medical therapy appears to be beneficial, there is a lack of clarity about the appropriate timing of when medical therapy should be used in relation with surgery, that is, before, after, or both before and after surgery, to maximize treatment response.

OBJECTIVES

To determine the effectiveness of medical therapies for hormonal suppression before, after, or both before and after surgery for endometriosis for improving painful symptoms, reducing disease recurrence, and increasing pregnancy rates.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and two trials registers in November 2019 together with reference checking and contact with study authors and experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) which compared medical therapies for hormonal suppression before, after, or before and after, therapeutic surgery for endometriosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias. Where possible, we combined data using risk ratio (RR), standardized mean difference or mean difference (MD) and 95% confidence intervals (CI). Primary outcomes were: painful symptoms of endometriosis as measured by a visual analogue scale (VAS) of pain, other validated scales or dichotomous outcomes; and recurrence of disease as evidenced by EEC (Endoscopic Endometriosis Classification), rAFS (revised American Fertility Society), or rASRM (revised American Society for Reproductive Medicine) scores at second-look laparoscopy.

MAIN RESULTS

We included 26 trials with 3457 women with endometriosis. We used the term "surgery alone" to refer to placebo or no medical therapy. Presurgical medical therapy compared with placebo or no medical therapy Compared to surgery alone, we are uncertain if presurgical medical hormonal suppression reduces pain recurrence at 12 months or less (dichotomous) (RR 1.10, 95% CI 0.72 to 1.66; 1 RCT, n = 262; very low-quality evidence) or whether it reduces disease recurrence at 12 months - total (AFS score) (MD -9.6, 95% CI -11.42 to -7.78; 1 RCT, n = 80; very low-quality evidence). We are uncertain if presurgical medical hormonal suppression decreases disease recurrence at 12 months or less (EEC stage) compared to surgery alone (RR 0.88, 95% CI 0.78 to 1.00; 1 RCT, n = 262; very low-quality evidence). We are uncertain if presurgical medical hormonal suppression improves pregnancy rates compared to surgery alone (RR 1.16, 95% CI 0.99 to 1.36; 1 RCT, n = 262; very low-quality evidence). No trials reported pelvic pain at 12 months or less (continuous) or disease recurrence at 12 months or less. Postsurgical medical therapy compared with placebo or no medical therapy We are uncertain about the improvement observed in pelvic pain at 12 months or less (continuous) between postsurgical medical hormonal suppression and surgery alone (MD -0.48, 95% CI -0.64 to -0.31; 4 RCTs, n = 419; I² = 94%; very low-quality evidence). We are uncertain if there is a difference in pain recurrence at 12 months or less (dichotomous) between postsurgical medical hormonal suppression and surgery alone (RR 0.85, 95% CI 0.65 to 1.12; 5 RCTs, n = 634; I² = 20%; low-quality evidence). We are uncertain if postsurgical medical hormonal suppression improves disease recurrence at 12 months - total (AFS score) compared to surgery alone (MD -2.29, 95% CI -4.01 to -0.57; 1 RCT, n = 51; very low-quality evidence). Disease recurrence at 12 months or less may be reduced with postsurgical medical hormonal suppression compared to surgery alone (RR 0.30, 95% CI 0.17 to 0.54; 4 RCTs, n = 433; I² = 58%; low-quality evidence). We are uncertain about the reduction observed in disease recurrence at 12 months or less (EEC stage) between postsurgical medical hormonal suppression and surgery alone (RR 0.80, 95% CI 0.70 to 0.91; 1 RCT, n = 285; very low-quality evidence). Pregnancy rate is probably increased with postsurgical medical hormonal suppression compared to surgery alone (RR 1.22, 95% CI 1.06 to 1.39; 11 RCTs, n = 932; I² = 24%; moderate-quality evidence). Pre- and postsurgical medical therapy compared with surgery alone or surgery and placebo There were no trials identified in the search for this comparison. Presurgical medical therapy compared with postsurgical medical therapy We are uncertain about the difference in pain recurrence at 12 months or less (dichotomous) between postsurgical and presurgical medical hormonal suppression therapy (RR 1.40, 95% CI 0.95 to 2.07; 2 RCTs, n = 326; I² = 2%; low-quality evidence). We are uncertain about the difference in disease recurrence at 12 months or less (EEC stage) between postsurgical and presurgical medical hormonal suppression therapy (RR 1.10, 95% CI 0.95 to 1.28; 1 RCT, n = 273; very low-quality evidence). We are uncertain about the difference in pregnancy rate between postsurgical and presurgical medical hormonal suppression therapy (RR 1.05, 95% CI 0.91 to 1.21; 1 RCT, n = 273; very low-quality evidence). No trials reported pelvic pain at 12 months or less (continuous), disease recurrence at 12 months - total (AFS score) or disease recurrence at 12 months or less (dichotomous). Postsurgical medical therapy compared with pre- and postsurgical medical therapy There were no trials identified in the search for this comparison. Serious adverse effects for medical therapies reviewed There was insufficient evidence to reach a conclusion regarding serious adverse effects, as no studies reported data suitable for analysis.

AUTHORS' CONCLUSIONS

Our results indicate that the data about the efficacy of medical therapy for endometriosis are inconclusive, related to the timing of hormonal suppression therapy relative to surgery for endometriosis. In our various comparisons of the timing of hormonal suppression therapy, women who receive postsurgical medical therapy compared with no medical therapy or placebo may experience benefit in terms of disease recurrence and pregnancy. There is insufficient evidence regarding hormonal suppression therapy at other time points in relation to surgery for women with endometriosis.

Pentoxifylline for endometriosis

BACKGROUND

Endometriosis is a chronic, recurring condition that occurs during the reproductive years. It is characterized by endometrial tissue developing outside the uterine cavity. This endometrial tissue development is dependent on oestrogen produced primarily by the ovaries and, therefore, traditional management has focused on ovarian suppression. In this review we considered the role of modulation of the immune system as an alternative approach. This is an update of a Cochrane Review previously published in 2009 (Lu 2009).

OBJECTIVES

To assess the effects of pentoxifylline, which has anti-inflammatory effects, in subfertile, premenopausal women for the management of endometriosis.

SEARCH METHODS

For the first publication of this review we searched the following databases (from inception to December 2008) for trials: Cochrane Menstrual Disorders and Subfertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE, CINAHL, and PsycINFO. In addition, all reference lists of included trials were searched and experts in the field were contacted in an attempt to locate trials. This search was rerun to 23 November 2011, for this update.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing pentoxifylline with placebo or no treatment, medical treatment, or surgery in subfertile, premenopausal women were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial risk of bias, and extracted data using data extraction forms. We contacted study authors for additional information and data. The domains assessed for risk of bias were sequence generation, allocation concealment, blinding, incomplete outcome data, and selective outcome reporting. Peto odds ratios (OR) were used for reporting dichotomous data with 95% confidence intervals (CI), whilst mean differences (MD) were expressed for continuous data. Statistical heterogeneity was assessed using the I(2) statistic.

MAIN RESULTS

Four trials involving 334 participants were included. One RCT [n=34] showed pentoxifylline had no significant effect on reduction in pain (MD -1.60, 95% CI -3.32 to 0.12). There was no evidence of an increase in clinical pregnancy events in the pentoxifylline group compared with placebo (three RCTs [n=67] OR 1.54, 95% CI 0.89 to 266). One RCT studied recurrence of endometriosis [n=88] (OR 0.88,95% CI 0.27 to 2.84). No trials reported the effects of pentoxifylline on the odds of live birth rate per woman, improvement of endometriosis-related symptoms, or adverse events.

AUTHORS' CONCLUSIONS

This review has been updated in 2011. The results of the original review published in 2009 remain unchanged. There is still not enough evidence to support the use of pentoxifylline in the management of premenopausal women with endometriosis in terms of subfertility and relief of pain outcomes.

Pre and post operative medical therapy for endometriosis surgery

BACKGROUND

Endometriosis is a common gynaecological condition which affects approximately 10% of women of reproductive age (Askenazi 1997). There is a range of symptoms and most commonly women present with dysmenorrhoea, pelvic pain, infertility or a pelvic mass. Direct visualisation and biopsy during laparoscopy or laparotomy is the gold standard diagnostic test for this condition and enables the gynaecologist to identify the location, extent and severity of the disease. Surgical therapy can be performed concurrently with diagnostic surgery and may include removal (excision) or destruction (ablation) of endometriotic tissue, division of adhesions and removal of endometriotic cysts. Laparoscopic excision or ablation of endometriosis has been shown to be effective in the management of pain in mild-moderate endometriosis. Adjunctive medical treatment pre or post-operatively may prolong the symptom-free interval.

OBJECTIVES

To determine the effectiveness of systemic medical therapies used for hormonal suppression before or after surgery for endometriosis, or before and after surgery for endometriosis in the eradication of endometriosis, improvement of symptoms, pregnancy rates and overall tolerability by comparing them with no treatment or placebo.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility group trials register (searched 10 September 2003), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3 2003), MEDLINE (January 1966 to September 2003), EMBASE (January 1985 to September 2003) and reference lists of articles. We also contacted researchers in the field.

SELECTION CRITERIA

Trials were included if they were randomised controlled trials of the use of systemic medical therapies for hormonal suppression before or after, or before and after surgery for endometriosis.

DATA COLLECTION AND ANALYSIS

Data extraction and quality assessment was performed independently by using relative risk or weighted mean difference and 95% confidence intervals.

MAIN RESULTS

Eleven trials were included in the review. One study comparing pre-surgical medical therapy with surgery alone showed a significant improvement in AFS scores in the medical therapy group (WMD -9.60, 95% CI -11.42 to -7.78) but this may or may not be associated with better outcomes for the patients. Post surgical hormonal suppression of endometriosis compared to surgery alone (either no medical therapy or placebo) showed no benefit for the outcomes of pain or pregnancy rates but a significant improvement in disease recurrence (AFS scores (WMD -2.30, 95% CI -4.02 to -0.58)). There were no trials identified in the search that compared hormonal suppression of endometriosis before and after surgery with surgery alone. There is no significant difference between pre surgery hormonal suppression and post surgery hormonal suppression for the outcome of pain in the one trial identified (RR 1.01, 95% CI 0.49 to 2.07). Information concerning AFS scores and ease of surgery was reported only as a descriptive summary so any difference between the groups can not be quantified from the information in the report of this trial.

REVIEWERS' CONCLUSIONS

There is insufficient evidence from the studies identified to conclude that hormonal suppression in association with surgery for endometriosis is associated with a significant benefit with regard to any of the outcomes identified. There may be a benefit of improvement in AFS scores with the pre-surgical use of medical therapy. The possible benefit should be weighed in the context of the adverse effects and costs of these therapies.