Risk of second malignant neoplasms in women and girls with germ cell tumors.

Background: While an elevated risk of second malignant neoplasms (SMNs) has been observed in men treated for germ cell tumors (GCTs), risk of SMNs have not been quantified in adult women or in girls treated for GCTs. Patients and methods: One-year survivors of primary GCTs diagnosed between January 1980 and December 2012 were identified from Surveillance, Epidemiology, and End Results (SEER 9) registries. Risk of SMNs was calculated using SEER*Stat. Results: Among 1507 patients, a total of 47 SMNs were identified. The overall risk of SMNs was not elevated in females overall or in females treated for GCT during adulthood although SMN sites (pancreas, soft tissue, bladder, kidney, and thyroid) and trends were comparable with those in men. There were too few childhood GCT cases with SMNs for further analysis. Conclusions: Unlike men, women treated for GCTs did not have a statistically significant elevated risk of SMNs [standardized incidence ratio = 1.11; 95% confidence interval (CI) = 0.81-1.47]. The fact that SMNs in women occur in sites similar to those observed in men indicate that long-term follow-up of a larger cohort of females treated for GCT is warranted.

Reproductive factors, exogenous hormone use and risk of hepatocellular carcinoma among US women: results from the Liver Cancer Pooling Project.

BACKGROUND: Hepatocellular carcinoma (HCC) occurs less commonly among women than men in almost all regions of the world. The disparity in risk is particularly notable prior to menopause suggesting that hormonal exposures during reproductive life may be protective. Exogenous oestrogenic exposures such as oral contraceptives (OCs), however, have been reported to increase risk, suggesting that estrogens may be hepatocarcinogenic. To examine the effects of reproductive factors and exogenous hormones on risk, we conducted a prospective analysis among a large group of US women. METHODS: In the Liver Cancer Pooling Project, a consortium of US-based cohort studies, data from 799,500 women in 11 cohorts were pooled and harmonised. Cox proportional hazards regression models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of reproductive factors and exogenous hormones with HCC (n=248). RESULTS: Bilateral oophorectomy was associated with a significantly increased risk of HCC (HR=2.67, 95% CI=1.22-5.85), which did not appear to be related to a shorter duration of exposure to endogenous hormones or to menopausal hormone therapy use. There was no association between OC use and HCC (HR=1.12, 95% CI=0.82-1.55). Nor were there associations with parity, age at first birth, age at natural menopause, or duration of fertility. CONCLUSIONS: The current study suggests that bilateral oophorectomy increases the risk of HCC but the explanation for the association is unclear. There was no association between OC use and HCC risk. Examination of endogenous hormone levels in relation to HCC may help to clarify the findings of the current study.

Exogenous hormone use, reproductive history and risk of adult myeloid leukaemia.

BACKGROUND: A hormonal aetiology is one explanation for the lower incidence of myeloid leukaemia in women compared with men. METHODS: In this population-based case-control study, we evaluated associations between exogenous hormone use and reproductive history and myeloid leukaemia, overall and by disease subtype. RESULTS: We observed a suggestive association between oral contraceptive use and acute myeloid leukaemia (odds ratio=0.55, 95% confidence interval=0.32-0.96). Hormone replacement therapy and reproductive factors were not associated with risk. CONCLUSION: Despite the biological plausibility for a role of oestrogen in leukaemogenesis, other aetiologic factors are likely to explain the differing incidence rates in males and females.

Paediatric germ cell tumours and congenital abnormalities: a Children's Oncology Group study.

METHODS: Maternally reported congenital abnormalities (CAs) were examined in a case-control study of 278 cases of paediatric germ cell tumours (GCTs) and 423 controls. RESULTS AND CONCLUSIONS: Germ cell tumours were significantly associated with cryptorchidism in males (OR=10.8, 95% CI: 2.1-55.1), but not with any other specific CA in either sex.

The role of Bcl-X(S) in radiation sensitivity.

Bcl-X(S) is a pro-apoptosis member of the Bcl2 family that has been shown to induce cell death and enhance chemosensitivity. We have investigated the effect of Bcl-X(S) overexpression on radiation sensitivity. Using a tetracycline-repressible system, we found that removal of tetracycline for 16 h induced Bcl-X(S) and reduced the surviving fraction of NIH 3T3 cells to 25%. However, radiation sensitivity was not significantly affected by Bcl-X(S) expression; the mean inactivation doses for Bcl-X(S) repressed and Bcl-X(S) induced cells were 2.7 +/- 0.3 and 2.3 +/- 0.1 Gy, respectively. We conclude that Bcl-X(S) induces cell death without affecting radiation sensitivity. These results suggest that mitochondrial pathways to apoptosis may not have a significant role in survival after irradiation.