Hormone replacement therapy for survivors of breast and endometrial cancer

Overweight, obesity and endometrial cancer risk: results from a systematic review and meta-analysis

AIM

Findings from recent studies suggest that obesity may be associated with an increased risk of endometrial cancer, but several earlier studies were less conclusive. Here we strive to estimate this relationship in a meta-analysis of published data.

METHODS

We searched Pubmed and Embase for studies on body mass index and the risk of endometrial cancer, published from 1989 to 2011. Data were independently extracted and analyzed using random or fixed effects meta-analysis depending on the degree of heterogeneity.

RESULTS

Seven cohort studies and 11 case-control studies were included in the meta-analysis. Overall, the conditions of excess body weight ([EBW] defined as body mass index [BMI] ≥25 kg/m²), obesity (BMI ≥30 kg/m²) and overweight (25< BMI <30 kg/m²) were associated with an increased risk of endometrial cancer (relative risk [RR] for EBW=1.62, 95% confidence interval [CI], 1.39-1.89; for obesity RR=2.54, 95% CI, 2.11-3.06; for overweight RR=1.32, 95% CI, 1.16-1.50). Subgroup analyses showed that the positive associations were independent of study design, geographic locations, self-reported BMI, alcohol use, smoking habit, history of diabetes, hormone therapy, age at menarche, age at menopause, parity, and age at first full term pregnancy. However, there was no statistically significant association between EBW and endometrial cancer risk for measured BMI (for EBW RR=1.29, 95% CI, 0.66-2.53).

CONCLUSIONS

The findings from this meta-analysis strongly support that the conditions of EBW, overweight, and obesity are all associated with an increased risk of endometrial cancer. Also, the strength of the association increases with increasing BMI.

Endometrial cancer patients and tibolone: A matched case–control study

OBJECTIVE

To evaluate whether tibolone had adverse effects on the prognosis of endometrial cancer patients.

METHODS

In this retrospective matched case-control study, out of 396 patients with endometrial cancer from January 1997 to December 2002, 68 patients who underwent complete surgical staging were identified as tibolone users (cases). For each case, one control as tibolone non-user was matched for stage and grade of disease, in this order of priority (ratio users: non-users, 1:1).

RESULTS

There were no significant differences in age (p = 0.11), stage (p = 1.00), grade (p = 0.96) and treatment modality (p = 0.55) between two arms. The mean duration of follow-up for tibolone users and tibolone non-users is 48.0 months and 54.4 months, respectively (p = 0.12). In tibolone users, a total of four patients recurred and two out of four patients died of disease. In tibolone non-users, there were three recurrences and all of three patients died of disease. There were no significant differences in disease free survival (p = 0.52) and overall survival (p = 0.61) between two arms. And there was no significant difference in disease free survival according to the duration of tibolone use (p = 0.14).

CONCLUSION

There was no evidence that tibolone had adverse effects on the disease free survival and overall survival of endometrial cancer patients. So, tibolone could be used in these patients.

Selective modulation of postmenopausal women: cutting the Gordian knot of hormone replacement therapy with breast carcinoma

BACKGROUND

Hormone replacement therapy (HRT) has proven and presumable benefits for women desiring postmenopausal health preservation. Among HRT-associated risks, the fear of breast carcinoma intimidates women and physicians contemplating hormonal treatment and limits long-term compliance. Identifying effective alternative medications that are not associated with breast carcinoma or that even may prevent its development would be a major advance.

METHODS

This article discusses the clinical perspective of HRT and selective estrogen receptor modulators (SERMs) in light of the molecular and cellular mechanisms of estrogen and progesterone action on the breast. Emphasis is placed on the potential of selective receptor modulation as the future of postmenopausal treatment.

RESULTS

Current epidemiologic evidence suggests that HRT is associated with a small but substantial increase in the risk of breast carcinoma, and combined estrogen-progesterone regimens further increase this hazard. Ample biologic data support this clinical association and propose multiple molecular mechanisms for the effects of estrogen and progesterone on breast cells. SERMs are a novel class of drugs that demonstrate estrogen agonistic and antagonistic actions in a tissue specific manner. SERMs act by binding the estrogen receptor and selectively modulating its effect on gene transcription at target tissues.

CONCLUSIONS

SERMs offer an alternative to HRT that can successfully circumvent the intimidating side-effect of breast carcinoma. Further insight into the molecular mechanisms of SERM action may enable the development of agents with improved target-tissue selectivity. Identifying selective modulators with unique pharmacologic properties would facilitate the creation of individualized treatment for the postmenopausal woman according to her particular predisposition for menopause-related morbidities and her overall clinical profile.