The Role of Ovarian Ablation in the Management of Breast Cancer

Secondary malignancies after rectal cancer resection with and without radiation therapy: A propensity-adjusted, population-based SEER analysis

BACKGROUND

The relationship between radiation therapy for rectal cancer and secondary malignancies is debated. The present study is the first population-based analysis using conventional multivariable analyses as well as propensity score matching to assess this relationship.

METHODS

Overall, 77,484 patients after resection of localized or locally advanced rectal adenocarcinoma diagnosed between 1973 and 2012 were identified in the Surveillance, Epidemiology, and End Results (SEER) registry. The occurrence of secondary malignancies diagnosed at least 1 (median follow up 5.8years [1-39.9years]) year after rectal cancer diagnosis was compared in patients who did and did not undergo radiation using stratified and propensity score matched Cox regression analysis.

RESULTS

Of 77,484 patients, 34,114 underwent radiation and 43,370 did not. Ignoring gender and entity, radiation therapy was not associated with secondary malignancies (hazard ratio [HR]=0.97 (95%CI: 0.92-1.02, P=0.269). The risk for prostate cancer was decreased and (HR=0.42, 95%CI: 0.36-0.48, P<0.001) and increased risk for endometrial cancer (HR=1.95, 95%CI: 1.49-2.56, P<0.001). Overall, patients undergoing radiation had higher risks for lung cancer (HR=1.18, 95%CI: 1.06-1.30, P<0.001), bladder cancer (HR=1.54, 95%CI: 1.31-1.80, P<0.001) and lymphomas (HR=1.27, 95%CI: 1.03-1.58, P=0.026).

CONCLUSIONS

The present analysis describes the occurence of secondary malignancies after pelvic radiation in patients undergoing rectal cancer surgery. Indeed, radiation for rectal cancer is associated with a significantly decreased risk of prostate cancer, however, an increased risk of endometrial, lung, and bladder cancer as well as lymphomas was observed. Overall, the risk of secondary malignancies was slightly decreased with radiation in patients undergoing rectal cancer resection, this was attributable to lower rates in prostate cancer.

The complex relationship between BRCA1 and ERalpha in hereditary breast cancer

Breast cancer 1 (BRCA1) was initially identified as one of the genes conferring genetic predisposition to both breast and ovarian cancer. One of the interesting aspects of BRCA1-linked cancers is the observed specificity for estrogen-responsive tissues such as breast and ovary. Recent advances in our understanding of BRCA1-linked breast cancers have revealed a complex relationship between BRCA1 and estrogen receptor alpha (ERalpha) signaling. Estrogen stimulation increases expression of BRCA1 at the mRNA and protein level and conversely BRCA1 functions to both induce ERalpha mRNA expression and act as a negative regulator of ERalpha signaling. Here, we review the relationship between BRCA1 and ERalpha and discuss the use of antiestrogen therapies such as tamoxifen and aromatase inhibitors in the treatment of BRCA1 mutation carriers.

A population-based analysis of second primary cancers after irradiation for rectal cancer

OBJECTIVE

To investigate the possible association between pelvic irradiation for rectal cancer and subsequent second primary cancers.

PATIENTS AND METHODS

A population-based analysis of 20,910 individuals with rectal cancer from the Surveillance, Epidemiology, and End Results registry, for whom follow-up times were at least 5 years, was performed. Kaplan-Meier estimates for the development of second cancers within irradiated and nonirradiated cohorts provided a comparison that accounted for censored data. Cox proportional hazards analyses were further conducted to compensate for patient and tumor-related factors.

RESULTS

A total of 656 (12%) and 2368 (16%) second primary cancers were enumerated from the irradiated and nonirradiated cohorts, respectively, with the proportion of second primary cancers within the irradiated cohort being significantly decreased (P < 0.001) on crude analysis. However, Kaplan-Meier and Cox analyses revealed no significant difference between the 2 cohorts when all second primary cancer sites were considered together (hazard ratio = 1.02; 95% confidence interval [CI], 0.92-1.12). Proportional hazards analysis for specific second primary sites revealed a decreased risk after pelvic irradiation for cancer of the prostate (hazard ratio = 0.63; 95% CI, 0.48-0.84), and an increased risk for cancers of the uterine corpus & cervix (hazard ratio = 2.5; 95% CI, 1.6-4.0).

CONCLUSION

Second primary cancers after irradiation for rectal cancers appear relatively infrequent compared with the background incidence of spontaneous cancers, and should not factor into treatment decisions for this older population. We hypothesize that the incidence of second primary tumors within adjacent organs could represent a balance between the radiation-induction of tumors and the radiation-inhibition of spontaneously occurring tumors.

Current controversies in the management of early breast cancer

Medical professionals in general, and medical oncologists in particular, have highly stressful practices because they are under constant pressure to have the highest-quality, up-to-date evidence available in order to make the right decision for each individual patient. From a practical point of view, being updated on oncological and other medical specialties may seem an insurmountable task because the number of scientific publications has increased dramatically. The use of systematic reviews of randomised controlled trials or the application of results obtained from high-quality randomised controlled trials are some of the most common ways to address this need. Unfortunately, they do not cover all complex clinical situations that the majority of medical oncologists face in their outpatient consultations. In this review, we report the conclusions achieved in a multiexpert meeting where five important controversies in the treatment of breast cancer were analysed. Five highly experienced medical oncologists were required to defend an affirmative answer and another five were required to defend a negative answer for each of the clinical questions. After that, a one-day meeting was organised to debate each clinical question and to reach a consensus. We report here the content of this multi-expert meeting along with the conclusions drawn.