Comparison of endocrine and radiation therapy in locally advanced prostatic cancer

Association of Androgen Deprivation Therapy and Thromboembolic Events: A Systematic Review and Meta-analysis

OBJECTIVES

To investigate the association of androgen deprivation therapy (ADT) for prostate cancer with thromboembolic events.

METHODS

PubMed, Web of Science, and Scopus were queried on April 5, 2017 for systematic review. Additionally, The World Health Organization International Trials Registry Platform was queried on June 23, 2017. Eligible studies reported thromboembolic events among individuals with prostate cancer exposed to ADT vs a lesser-exposed group. Five hundred sixty-nine unique studies were identified with 65 undergoing full-text review. We utilized the Meta-analysis of Observational Studies in Epidemiology statement guidelines and the Cochrane Review Group's data extraction template. Study quality was evaluated by Newcastle-Ottawa Scale criteria. We conducted random-effects meta-analyses to calculate summary statistic risk ratios and 95% confidence intervals. Heterogeneity was quantified using the I2 statistic. Small study effects were evaluated using Begg and Egger statistics.

RESULTS

In 10 studies "ADT without estrogen" increased the risk of thromboembolic events (risk ratio [RR] 1.43, 95% confidence interval [CI] 1.15-1.77, P = .001). In 9 studies estrogen therapy alone was associated with an increased risk of thromboembolic events (RR 3.72, 95% CI 1.78-7.80, P <.001). We found an increased risk of thromboembolic events from ADT use without estrogen when limited to localized disease (RR 1.10, 95% CI 1.05-1.16, P <.001). Heterogeneity was resolved in those studies examining localized disease. There was no evidence of small study effects.

CONCLUSION

The currently available evidence suggests that ADT without estrogen is associated with an increased the risk of thromboembolic events.

Parenteral oestrogen in the treatment of prostate cancer: a systematic review

The objectives of this study were to assess the effectiveness and safety of parenteral oestrogen in the treatment of prostate cancer, and to examine any dose relationship. A systematic review was undertaken. Electronic databases, published paper and internet resources were searched to locate published and unpublished studies with no restriction by language or publication date. Studies included were randomised controlled trials of parenteral oestrogen in patients with prostate cancer; other study designs were also included to examine dose-response. Study selection, appraisal, data extraction and quality assessment were performed by one reviewer and independently checked by another. Twenty trials were included in the review. The trials differed with regard to the included patients, formulation and dose of parenteral oestrogen, comparator used, outcome measures reported and the duration of follow-up. The results provide no evidence to suggest that parenteral oestrogen, in doses sufficient to produce castrate levels of testosterone, is less effective than luteinising hormone-releasing hormone (LHRH) or orchidectomy in controlling prostate cancer, or that it is consistently associated with an increase in cardiovascular mortality. Further well-conducted trials of parenteral oestrogen are required. A pilot randomised controlled trial comparing transdermal oestrogen to LHRH analogues in men with locally advanced or metastatic prostate cancer is underway in the United Kingdom.

Primary radiation therapy in the treatment of localized prostatic cancer

Prostatic carcinoma is one of the leading causes of male cancer deaths. However, the routine diagnostic and therapeutic strategies have not yet been established. Although the outcome of surgical and radiotherapeutical approaches has frequently been reported to be comparable, the profile of side effects is different. This could offer the basis for selecting the treatment of choice in individual cases. During the last decade the radiotherapeutical technique has markedly improved, in part due to the achievements in the field of computer assisted tomography planning and conformal technique; the outcome of side-effects has decreased with concurrent increase in the rate of local control. The prescribing, recording and reporting of irradiation have also recently developed, as well as the staging of the disease. Therefore we consider it timely to review progress in this subject and to emphasize the role of radiotherapy in the treatment of localized prostatic cancer.

Orchiectomy versus oestrogen in the treatment of advanced prostatic cancer

The primary clinical efficacy of orchiectomy and the combination therapy of intramuscular polyoestradiol phosphate 80 mg monthly and oral ethinyl oestradiol 0.15 mg daily was evaluated by progression and cancer mortality rates in a series of 277 prostatic cancer patients representing part of the Finnprostate study. After a follow-up of 5 years there was a significant difference between the groups in terms of progression rate and prostatic cancer deaths. The oestrogen combination was more effective in delaying progression of the disease. The overall mortality rate was similar in both groups. About one-third of the patients were alive after 5 years.

Cardiovascular and all-cause mortality in prostatic cancer patients treated with estrogens or orchiectomy as compared to the standard population

Four hundred and seventy-seven prospectively randomized patients with prostatic carcinoma were treated with a combination of intramuscular polyestradiol phosphate (PEP) and oral ethinyl estradiol, with intramuscular PEP alone, or with orchiectomy. The cardiovascular and all-cause mortality of the two estrogen therapy modalities and orchiectomy were compared with those of the Finnish male population in general. The age-standardized rate ratios (approximately relative risk) for cardiovascular mortality and for all-cause mortality were 1.51 and 2.31 in the combination estrogen therapy group, 0.17 and 1.50 in the PEP monotherapy group, and 0.78 and 1.78 in the orchiectomy group, respectively. Further mortality rates by cause for all three treatment groups were standardized for age using the age-specific person-years at risk as standard. Age-standardized mortality from cardiovascular diseases was very low in the PEP group, as compared to other treatment modalities, and the mortality rates for prostatic cancer were about equal in all three treatment groups. It is concluded that intramuscular PEP monotherapy is associated with low cardiovascular mortality and with an all-cause and prostatic cancer mortality equal to orchiectomy.