Global epidemiology of epithelial ovarian cancer

Globally, ovarian cancer is the eighth most common cancer in women, accounting for an estimated 3.7% of cases and 4.7% of cancer deaths in 2020. Until the early 2000s, age-standardized incidence was highest in northern Europe and North America, but this trend has changed; incidence is now declining in these regions and increasing in parts of eastern Europe and Asia. Ovarian cancer is a very heterogeneous disease and, even among the most common type, namely epithelial ovarian cancer, five major clinically and genetically distinct histotypes exist. Most high-grade serous ovarian carcinomas are now recognized to originate in the fimbrial ends of the fallopian tube. This knowledge has led to more cancers being coded as fallopian tube in origin, which probably explains some of the apparent declines in ovarian cancer incidence, particularly in high-income countries; however, it also suggests that opportunistic salpingectomy offers an important opportunity for prevention. The five histotypes share several reproductive and hormonal risk factors, although differences also exist. In this Review, we summarize the epidemiology of this complex disease, comparing the different histotypes, and consider the potential for prevention. We also discuss how changes in the prevalence of risk and protective factors might have contributed to the observed changes in incidence and what this might mean for incidence in the future.

Risk Factors for Ovarian Cancer by BRCA Status: A Collaborative Case-Only Analysis

BACKGROUND

Women with an inherited pathogenic variant in BRCA1 or BRCA2 have a greatly increased risk of developing ovarian cancer, but the importance of behavioral factors is less clear. We used a case-only design to compare the magnitude of associations with established reproductive, hormonal, and lifestyle risk factors between BRCA mutation carriers and noncarriers.

METHODS

We pooled data from five studies from the Ovarian Cancer Association Consortium including 637 BRCA carriers and 4,289 noncarriers. Covariate-adjusted generalized linear mixed models were used to estimate interaction risk ratios (IRR) and 95% confidence intervals (CI), with BRCA (carrier vs. noncarrier) as the response variable.

RESULTS

IRRs were above 1.0 for known protective factors including ever being pregnant (IRR = 1.29, 95% CI; 1.00-1.67) and ever using the oral contraceptive pill (1.30, 95% CI; 1.07-1.60), suggesting the protective effects of these factors may be reduced in carriers compared with noncarriers. Conversely, the IRRs for risk factors including endometriosis and menopausal hormone therapy were below 1.0, suggesting weaker positive associations among BRCA carriers. In contrast, associations with lifestyle factors including smoking, physical inactivity, body mass index, and aspirin use did not appear to differ by BRCA status.

CONCLUSIONS

Our results suggest that associations with hormonal and reproductive factors are generally weaker for those with a pathogenic BRCA variant than those without, while associations with modifiable lifestyle factors are similar for carriers and noncarriers.

IMPACT

Advice to maintain a healthy weight, be physically active, and refrain from smoking will therefore benefit BRCA carriers as well as noncarriers.

Mismatch repair status and surgical approach in apparent early-stage endometrial cancer

OBJECTIVE

To test the hypothesis that mismatch repair (MMR) status (as an accurate surrogate marker for microsatellite stability) modifies the effect of surgical approach on oncological outcome for apparent early-stage endometrial cancer.

METHODS

Observational data from a large prospective population study on endometrial cancer were analyzed using target trial methodology and doubly robust methods, including propensity score matching and adjusted regression analyses. Laparoscopy was compared with laparotomy, stratified by MMR status on outcomes of recurrence and site, and recurrence-free, overall, and disease-specific survival.

RESULTS

After matching, there were 400 patients for analysis, with 200 in each treatment group. The mean age was 62 years and mean body mass index was 32 kg/m2. Most patients had early-stage disease (stage I n=362 (90%)) and endometrioid histology (n=363 (91%)). Adjuvant pelvic radiation was administered to 11%, adjuvant vaginal brachytherapy to 13% and adjuvant chemotherapy to 5% of patients. Five-year recurrence-free survival did not differ significantly between modes of surgery across the cohort (p=0.7) or within MMR strata (MMR-proficient p=0.9, MMR-deficient p=0.6). Similarly, there was no significant difference in overall or disease-specific survival by mode of surgery across the cohort or within MMR strata. There was no significant difference in the HR for recurrence for those treated with laparoscopy stratified by MMR status (MMR-proficient HR=0.99 (95% CI 0.28 to 3.58); MMR-deficient HR=0.83 (95% CI 0.24 to 2.87)), even when restricted to endometrioid subtype.

CONCLUSION

In this study, there was no evidence of a difference in survival outcomes according to mode of surgery and MMR status.

The effect of three years of vitamin D supplementation on erectile dysfunction: Results from the randomized placebo-controlled D-Health Trial

BACKGROUND & AIMS

Erectile dysfunction is common among older men and has been associated with low serum 25-hydroxy vitamin D concentration. However, this association may be due to uncontrolled confounding, and there is a paucity of evidence from interventional studies. We aimed to examine the effect of vitamin D supplementation on the prevalence of erectile dysfunction, in an exploratory analysis using data from a large randomized controlled trial.

METHODS

The D-Health Trial recruited Australians aged 60-84 years between January 2014 and May 2015 and randomly assigned them to supplementation with 60,000 IU of vitamin D or placebo per month for up to 5 years. Blood samples were collected annually from randomly selected participants (total N = 3943). We assessed erectile dysfunction at the end of the third year of follow-up. We used log-binomial regression to examine the effect of vitamin D on the prevalence of erectile dysfunction overall, and within sub-groups.

RESULTS

Of the 11,530 men enrolled, 8920 (77.4 %) completed the erectile dysfunction question and were included in the analysis. After three years of supplementation, the mean serum 25-hydroxy vitamin D concentration was 76 nmol/L (standard deviation (SD) 24.94) in the placebo group and 106 nmol/L (SD 26.76) in the vitamin D group (p < 0.0001). The prevalence of erectile dysfunction was 58.8 % and 59.0 % in the vitamin D and placebo groups, respectively (prevalence ratio 1.00, 95 % CI 0.97, 1.03); there was no evidence of an effect of vitamin D in any subgroup analyses.

CONCLUSION

Supplementing older men with vitamin D is unlikely to prevent or improve erectile dysfunction.

CLINICAL TRIALS REGISTRY

(ACTRN12613000743763).

Hypertension and risk of endometrial cancer: a pooled analysis in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

The incidence rates of endometrial cancer (EC) are increasing, which may partly be explained by the rising prevalence of obesity, an established risk factor for EC. Hypertension, another component of metabolic syndrome, is also increasing in prevalence, and emerging evidence suggests that it may be associated with the development of certain cancers. The role of hypertension independent of other components of metabolic syndrome in the etiology of EC remains unclear. In this study we evaluated hypertension as an independent risk factor for EC and whether this association is modified by other established risk factors.

METHODS

We included 15,631 EC cases and 42,239 controls matched on age, race, and study-specific factors from 29 studies in the Epidemiology of Endometrial Cancer Consortium. We used multivariable unconditional logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) to evaluate the association between hypertension and EC and whether this association differed by study design, race/ethnicity, body mass index, diabetes status, smoking status, or reproductive factors.

RESULTS

Hypertension was associated with an increased risk of EC (OR=1.14, 95% CI:1.09-1.19). There was significant heterogeneity by study design (Phet<0.01), with a stronger magnitude of association observed among case-control vs. cohort studies. Stronger associations were also noted for pre-/peri-menopausal women and never users of postmenopausal hormone therapy.

CONCLUSIONS

Hypertension is associated with EC risk independently from known risk factors. Future research should focus on biologic mechanisms underlying this association.

IMPACT

This study provides evidence that hypertension may be an independent risk factor for EC.

Genome-wide association analyses of ovarian cancer patients undergoing primary debulking surgery identify candidate genes for residual disease

Survival from ovarian cancer depends on the resection status after primary surgery. We performed genome-wide association analyses for resection status of 7705 ovarian cancer patients, including 4954 with high-grade serous carcinoma (HGSOC), to identify variants associated with residual disease. The most significant association with resection status was observed for rs72845444, upstream of MGMT, in HGSOC (p = 3.9 × 10-8). In gene-based analyses, PPP2R5C was the most strongly associated gene in HGSOC after stage adjustment. In an independent set of 378 ovarian tumours from the AGO-OVAR 11 study, variants near MGMT and PPP2R5C correlated with methylation and transcript levels, and PPP2R5C mRNA levels predicted progression-free survival in patients with residual disease. MGMT encodes a DNA repair enzyme, and PPP2R5C encodes the B56γ subunit of the PP2A tumour suppressor. Our results link heritable variation at these two loci with resection status in HGSOC.

Large-scale genome-wide association study of 398,238 women unveils seven novel loci associated with high-grade serous epithelial ovarian cancer risk

Background

Nineteen genomic regions have been associated with high-grade serous ovarian cancer (HGSOC). We used data from the Ovarian Cancer Association Consortium (OCAC), Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA), UK Biobank (UKBB), and FinnGen to identify novel HGSOC susceptibility loci and develop polygenic scores (PGS).

Methods

We analyzed >22 million variants for 398,238 women. Associations were assessed separately by consortium and meta-analysed. OCAC and CIMBA data were used to develop PGS which were trained on FinnGen data and validated in UKBB and BioBank Japan.

Results

Eight novel variants were associated with HGSOC risk. An interesting discovery biologically was finding that TP53 3'-UTR SNP rs78378222 was associated with HGSOC (per T allele relative risk (RR)=1.44, 95%CI:1.28-1.62, P=1.76×10-9). The optimal PGS included 64,518 variants and was associated with an odds ratio of 1.46 (95%CI:1.37-1.54) per standard deviation in the UKBB validation (AUROC curve=0.61, 95%CI:0.59-0.62).

Conclusions

This study represents the largest GWAS for HGSOC to date. The results highlight that improvements in imputation reference panels and increased sample sizes can identify HGSOC associated variants that previously went undetected, resulting in improved PGS. The use of updated PGS in cancer risk prediction algorithms will then improve personalized risk prediction for HGSOC.

Impact of disease recurrence on the supportive care needs of patients with ovarian cancer and their caregivers

OBJECTIVE

We aimed to explore the supportive care needs of ovarian cancer patients and their caregivers before and after the first cancer recurrence, the top unmet needs after recurrence, and the relationship between patient and caregiver needs at recurrence.

METHODS

Participants were 288 patients and 140 caregivers from the Australian Ovarian Cancer Study-Quality of Life (AOCS-QoL) cohort. They completed Supportive Care Needs Surveys (patients: SCNS-SF34, caregivers: SCNS-P&C44) every three-to-six months for up to two years. Linear mixed models tracked changes in needs over time. We calculated the percentage reporting moderate-to-high needs after recurrence. LASSO regression analysed patient-caregiver need relationships.

RESULTS

Both patients' and caregivers' psychological, health system/service and information needs increased with recurrence along with patients' support and physical needs. These remained stable at nine months after recurrence. Dominant patient needs post-recurrence included 'fear of recurrence' (38%) and 'concerns about the worries of those close' (34%), while caregivers expressed 'concerns about recurrence' (41%) and 'recovery of the patient not turning out as expected' (31%). Among dyads, when patients had 'fears about the cancer spreading' this was associated with caregivers having a need for help with 'reducing stress in the patients' life'; when caregivers had concerns about 'recurrence' this was associated with patients needing help with 'uncertainty about the future' and 'information about things they can do to help themselves'.

CONCLUSIONS

Recurrent ovarian cancer intensifies disease-related fears and concerns for patients and loved ones. Addressing dyadic concerns through supportive care interventions may enhance cohesion during the challenging journey of recurrent disease.

Association between unstable diabetes mellitus and risk of pancreatic cancer

BACKGROUND

Deterioration of glycaemic control in people with long-standing diabetes mellitus (diabetes) may be a possible indicator of pancreatic cancer. However, the magnitude of the association between diabetes deterioration and pancreatic cancer has received little attention.

METHODS

We conducted a matched cohort study, nested within a population-based cohort of Australian women with diabetes. Women with unstable diabetes, defined as a change in medication after a 2-year period of stable medication use, were matched by birth year to those with stable diabetes, in a 1:4 ratio. We used flexible parametric survival models to estimate hazard ratios (HRs) and 95% confidence intervals (CI).

RESULTS

We included 134,954 and 539,789 women in the unstable and stable diabetes cohorts, respectively (mean age 68 years). In total, 1,315 pancreatic cancers were diagnosed. Deterioration of stable diabetes was associated with a 2.5-fold increased risk of pancreatic cancer (HR 2.55; 95% CI 2.29-2.85). The risk was particularly high within the first year after diabetes deteriorated. HRs at 3 months, 6 months and 1 year were: 5.76 (95% CI 4.72-7.04); 4.56 (95% CI 3.81-5.46); and 3.33 (95% CI 2.86-3.89), respectively. The risk was no longer significantly different after 7 years.

CONCLUSIONS

Deterioration in glycaemic control in people with previously stable diabetes may be an indicator of pancreatic cancer, suggesting investigations of the pancreas may be appropriate. The weaker longer-term (3-7 years) association between diabetes deterioration and pancreatic cancer may indicate that poor glycaemic control can be a risk factor for pancreatic cancer.

Mental health and diet quality after primary treatment for ovarian cancer

AIMS

To investigate anxiety and depression after primary treatment for ovarian cancer in relation to diet quality and intake.

METHODS

In a cohort of women with ovarian cancer in Australia, levels of anxiety and depression (normal, subclinical, and clinical) were assessed using the Hospital Anxiety and Depression Scale at 9 months post-diagnosis. Dietary intake was assessed using a validated food frequency questionnaire at 12 months post-diagnosis and scored using the Healthy Eating Index 2015. Multinomial logistic regression and bivariate analyses were used to investigate relationships between levels of anxiety and depression and subsequent diet quality and intake of food groups.

RESULTS

Of 595 women, anxiety and depression were identified among 128 (21%) and 80 (13%) women, respectively. Compared to women without anxiety or depression, women with subclinical anxiety (odds ratio = 0.49, 95% confidence interval: 0.25-0.98) and those with clinical depression (odds ratio = 0.25, 95% confidence interval: 0.07-0.93) were less likely to score in the highest quartile for diet quality. Separate adjustment for age, education, employment, disease stage, body mass index, and smoking status did not attenuate these associations. In bivariate analyses, women with subclinical anxiety were more likely to report higher intakes of sweet foods. Those with clinical depression were more likely to report lower intakes of orange vegetables and wholegrains, higher intakes of sweetened beverages, and not consume alcohol or soya foods.

CONCLUSIONS

Anxiety or depression after primary treatment for ovarian cancer may be associated with poorer diet quality. Efforts to improve diet quality post-treatment should consider support for mental health.

Vitamin D status during and after treatment and ovarian cancer survival

PURPOSE

Five-year relative survival for ovarian cancer remains below 50%. Strategies to improve outcomes are needed. Higher serum 25-hydroxyvitamin D [25(OH)D] concentrations [measure of vitamin D status] at and before diagnosis have been associated with longer survival in cancer patients; however, data for ovarian cancer are limited. We aimed to determine if 25(OH)D concentrations during and after primary treatment were associated with ovarian cancer-specific survival.

METHODS

We used data from a nationwide prospective cohort study of women with ovarian cancer. Among 886 participants treated with chemotherapy, 700 (79%) had a blood sample collected during (n = 591) and/or after (n = 458) primary treatment. These were tested for 25(OH)D. Clinical and survival data were abstracted from medical records. We used multivariable Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for associations between 25(OH)D and ovarian cancer-specific survival.

RESULTS

Mean 25(OH)D concentrations were lower during than after primary treatment (82 and 91 nmol/L, respectively); only 14% and 8% had concentrations below 50 nmol/L during and after primary treatment, respectively. There was no association between 25(OH)D and ovarian cancer-specific survival during five years of follow-up [HR 1.10 (95% CI: 0.76, 1.61) and 0.95 (0.54, 1.68) for the highest vs. lowest quintile during and after treatment, respectively].

CONCLUSIONS

We did not observe any association between serum 25(OH)D concentration and ovarian cancer-specific survival. Our results suggest that, in the absence of vitamin D deficiency, vitamin D supplementation to improve ovarian cancer survival is not warranted.

A framework for assessing interactions for risk stratification models: the example of ovarian cancer

Generally, risk stratification models for cancer use effect estimates from risk/protective factor analyses that have not assessed potential interactions between these exposures. We have developed a 4-criterion framework for assessing interactions that includes statistical, qualitative, biological, and practical approaches. We present the application of this framework in an ovarian cancer setting because this is an important step in developing more accurate risk stratification models. Using data from 9 case-control studies in the Ovarian Cancer Association Consortium, we conducted a comprehensive analysis of interactions among 15 unequivocal risk and protective factors for ovarian cancer (including 14 non-genetic factors and a 36-variant polygenic score) with age and menopausal status. Pairwise interactions between the risk/protective factors were also assessed. We found that menopausal status modifies the association among endometriosis, first-degree family history of ovarian cancer, breastfeeding, and depot-medroxyprogesterone acetate use and disease risk, highlighting the importance of understanding multiplicative interactions when developing risk prediction models.

The Effect of Vitamin D Supplementation on Hypothyroidism in the Randomized Controlled D-Health Trial

Background: Hypothyroidism is common, and in iodine-sufficient areas, it is primarily caused by autoimmune destruction of the thyroid gland. Observational studies have consistently shown an inverse association between serum 25-hydroxyvitamin D concentration and autoimmune diseases; however, there is a lack of evidence from randomized controlled trials to support a benefit of vitamin D supplementation, particularly for autoimmune thyroid diseases. We, therefore, aimed to assess the effect of vitamin D supplementation on the incidence of hypothyroidism. Methods: We analyzed data from the D-Health Trial (n = 21,315), a randomized double-blind placebo-controlled trial of 60,000 international units per month of supplemental vitamin D3 among Australians aged 60 years and over. Hypothyroidism, a tertiary outcome of the D-Health Trial, was defined by treatment with levothyroxine, ascertained through linkage with the Australian Pharmaceutical Benefits Scheme. The outcome was time to first prescription of levothyroxine. We began follow-up at 12 months after randomization; people who had died or who had been dispensed levothyroxine during the first year were excluded. Flexible parametric survival models were used to assess the effect of vitamin D supplementation on hypothyroidism, overall and within strata defined by age, sex, body mass index, and predicted baseline vitamin D status. Results: We included 17,851 participants in the main analysis (vitamin D = 8939; placebo = 8912). During a median follow-up of 4.1 years (interquartile range 4.1-4.1), 293 participants developed hypothyroidism (vitamin D = 138 [1.5%]; placebo = 155 [1.7%]). Vitamin D supplementation did not significantly reduce the incidence of hypothyroidism (overall hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.71-1.12). There was some suggestion of an effect in females (overall HR 0.78; CI 0.58-1.06) but not in males (overall HR 1.06; CI 0.74-1.50; p interaction 0.20). Conclusions: Vitamin D supplementation did not reduce the incidence of hypothyroidism overall; however, the possible beneficial effect observed in females warrants further investigation. Clinical Trial Registration: Australian New Zealand Clinical Trials Registry: ACTRN12613000743763.

Association between antihypertensive medicine use and risk of ovarian cancer in women aged 50 years and older

BACKGROUND

Epithelial ovarian cancer (EOC) has few modifiable risk factors. There is evidence that some antihypertensive medicines may have cancer preventive and/or therapeutic actions; therefore, we assessed the associations between use of different antihypertensive medicines and risk of specific EOC histotypes.

METHODS

Our nested case-control study of linked administrative health data included 6070 Australian women aged over 50 years diagnosed with EOC from 2004 to 2013, and 30,337 matched controls. We used multivariable conditional logistic regression to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) for the association between ever use of each antihypertensive medicine group, including beta-adrenergic blockers, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, diuretics, and alpha blockers, and the risk of EOC overall and separately for the serous, endometrioid, mucinous, clear cell and other histotypes.

RESULTS

We found that most antihypertensive medicines were not associated with risk of EOC. However, women who used calcium channel blockers had a reduced risk of serous EOC (OR= 0.89, 95 % CI:0.81,0.98) and use of combination thiazide and potassium-sparing diuretics was associated with an increased risk of endometroid EOC (OR= 2.09, 95 % CI:1.15,3.82).

CONCLUSION

Our results provide little support for a chemo-preventive role for most antihypertensives, however, the histotype-specific associations we found warrant further investigation.

Folate Intake and Ovarian Cancer Risk among Women with Endometriosis: A Case-Control Study from the Ovarian Cancer Association Consortium

BACKGROUND

Although folate intake has not been associated with an increased risk of ovarian cancer overall, studies of other cancer types have suggested that high folate intake may promote carcinogenesis in precancerous lesions. Women with endometriosis (a potential precancerous lesion) have an increased risk of developing ovarian cancer; however, whether high folate intake increases risk in this group is unknown.

METHODS

We conducted a pooled analysis of six case-control studies from the Ovarian Cancer Association Consortium to investigate the association between folate intake and risk of ovarian cancer among women with and without self-reported endometriosis. We included 570 cases/558 controls with and 5,171/7,559 without endometriosis. We used logistic regression to estimate odds ratios (OR) and 95% confidence intervals for the association between folate intake (dietary, supplemental, and total) and ovarian cancer risk. Finally, we used Mendelian randomization (MR) to evaluate our results using genetic markers as a proxy for folate status.

RESULTS

Higher dietary folate intake was associated with an increased risk of ovarian cancer for women with endometriosis [OR, 1.37 (1.01-1.86)] but not for women without endometriosis. There was no association between supplemental folate intake and ovarian cancer risk for women with or without endometriosis. A similar pattern was seen using MR.

CONCLUSIONS

High dietary folate intake may be associated with an increased risk of ovarian cancer among women with endometriosis.

IMPACT

Women with endometriosis with high folate diets may be at increased risk of ovarian cancer. Further research is needed on the potential cancer-promoting effects of folate in this group.

Vitamin D supplementation and major cardiovascular events: D-Health randomised controlled trial

OBJECTIVE

To investigate whether supplementing older adults with monthly doses of vitamin D alters the incidence of major cardiovascular events.

DESIGN

Randomised, double blind, placebo controlled trial of monthly vitamin D (the D-Health Trial). Computer generated permuted block randomisation was used to allocate treatments.

SETTING

Australia from 2014 to 2020.

PARTICIPANTS

21 315 participants aged 60-84 years at enrolment. Exclusion criteria were self-reported hypercalcaemia, hyperparathyroidism, kidney stones, osteomalacia, sarcoidosis, taking >500 IU/day supplemental vitamin D, or unable to give consent because of language or cognitive impairment.

INTERVENTION

60 000 IU/month vitamin D₃ (n=10 662) or placebo (n=10 653) taken orally for up to five years. 16 882 participants completed the intervention period: placebo 8270 (77.6%); vitamin D 8552 (80.2%).

MAIN OUTCOME MEASURES

The main outcome for this analysis was the occurrence of a major cardiovascular event, including myocardial infarction, stroke, and coronary revascularisation, determined through linkage with administrative datasets. Each event was analysed separately as secondary outcomes. Flexible parametric survival models were used to estimate hazard ratios and 95% confidence intervals.

RESULTS

21 302 people were included in the analysis. The median intervention period was five years. 1336 participants experienced a major cardiovascular event (placebo 699 (6.6%); vitamin D 637 (6.0%)). The rate of major cardiovascular events was lower in the vitamin D group than in the placebo group (hazard ratio 0.91, 95% confidence interval 0.81 to 1.01), especially among those who were taking cardiovascular drugs at baseline (0.84, 0.74 to 0.97; P for interaction=0.12), although the P value for interaction was not significant (<0.05). Overall, the difference in standardised cause specific cumulative incidence at five years was -5.8 events per 1000 participants (95% confidence interval -12.2 to 0.5 per 1000 participants), resulting in a number needed to treat to avoid one major cardiovascular event of 172. The rate of myocardial infarction (hazard ratio 0.81, 95% confidence interval 0.67 to 0.98) and coronary revascularisation (0.89, 0.78 to 1.01) was lower in the vitamin D group, but there was no difference in the rate of stroke (0.99, 0.80 to 1.23).

CONCLUSIONS

Vitamin D supplementation might reduce the incidence of major cardiovascular events, although the absolute risk difference was small and the confidence interval was consistent with a null finding. These findings could prompt further evaluation of the role of vitamin D supplementation, particularly in people taking drugs for prevention or treatment of cardiovascular disease.

TRIAL REGISTRATION

ACTRN12613000743763.

Vitamin D supplementation and cognition-Results from analyses of the D-Health trial

BACKGROUND

Observational studies have consistently found a link between low serum 25-hydroxyvitamin D concentration and higher risk of cognitive impairment. Results from randomized controlled trials have been mixed, and few have been conducted in the general population.

METHODS

We recruited 21,315 community-dwelling Australians aged between 60 and 84 years to participate in the D-Health Trial, a randomized, double-blind, placebo-controlled trial. The intervention was monthly oral doses of 60,000 international units of vitamin D or placebo for 5 years. We assessed cognitive function in a randomly sampled group of participants aged ≥70 years using the Telephone Interview for Cognitive Status (TICS) at 2 and 5 years after randomization. The primary outcome for this analysis was TICS score; the secondary outcome was the proportion of people who had cognitive impairment (defined as TICS score ≤25). We analyzed data using mixed models (linear and logistic).

RESULTS

We interviewed 3887 participants at year 2 and 3614 participants at year 5. The mean TICS score at these time points was 32.3 and 32.2, respectively. Vitamin D supplementation did not affect cognitive function as measured by TICS score (mean difference between vitamin D and placebo groups 0.04; 95% CI -0.14 to 0.23), or alter risk of cognitive impairment (odds ratio 1.00; 95% CI 0.75 to 1.33).

CONCLUSIONS

Monthly bolus doses of vitamin D supplementation neither enhanced nor hindered cognitive function among older adults. Population-wide vitamin D supplementation of older adults that are largely vitamin D replete is unlikely to substantially benefit cognition.

Risk prediction models for endometrial cancer: development and validation in an international consortium

BACKGROUND

Endometrial cancer risk stratification may help target interventions, screening, or prophylactic hysterectomy to mitigate the rising burden of this cancer. However, existing prediction models have been developed in select cohorts and have not considered genetic factors.

METHODS

We developed endometrial cancer risk prediction models using data on postmenopausal White women aged 45-85 years from 19 case-control studies in the Epidemiology of Endometrial Cancer Consortium (E2C2). Relative risk estimates for predictors were combined with age-specific endometrial cancer incidence rates and estimates for the underlying risk factor distribution. We externally validated the models in 3 cohorts: Nurses' Health Study (NHS), NHS II, and the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

RESULTS

Area under the receiver operating characteristic curves for the epidemiologic model ranged from 0.64 (95% confidence interval [CI] = 0.62 to 0.67) to 0.69 (95% CI = 0.66 to 0.72). Improvements in discrimination from the addition of genetic factors were modest (no change in area under the receiver operating characteristic curves in NHS; PLCO = 0.64 to 0.66). The epidemiologic model was well calibrated in NHS II (overall expected-to-observed ratio [E/O] = 1.09, 95% CI = 0.98 to 1.22) and PLCO (overall E/O = 1.04, 95% CI = 0.95 to 1.13) but poorly calibrated in NHS (overall E/O = 0.55, 95% CI = 0.51 to 0.59).

CONCLUSIONS

Using data from the largest, most heterogeneous study population to date (to our knowledge), prediction models based on epidemiologic factors alone successfully identified women at high risk of endometrial cancer. Genetic factors offered limited improvements in discrimination. Further work is needed to refine this tool for clinical or public health practice and expand these models to multiethnic populations.

Lifetime ovulatory years and risk of epithelial ovarian cancer: a multinational pooled analysis

BACKGROUND

The role of ovulation in epithelial ovarian cancer (EOC) is supported by the consistent protective effects of parity and oral contraceptive use. Whether these factors protect through anovulation alone remains unclear. We explored the association between lifetime ovulatory years (LOY) and EOC.

METHODS

LOY was calculated using 12 algorithms. Odds ratios (ORs) and 95% confidence intervals (CIs) estimated the association between LOY or LOY components and EOC among 26 204 control participants and 21 267 case patients from 25 studies. To assess whether LOY components act through ovulation suppression alone, we compared beta coefficients obtained from regression models with expected estimates assuming 1 year of ovulation suppression has the same effect regardless of source.

RESULTS

LOY was associated with increased EOC risk (OR per year increase = 1.014, 95% CI = 1.009 to 1.020 to OR per year increase = 1.044, 95% CI = 1.041 to 1.048). Individual LOY components, except age at menarche, also associated with EOC. The estimated model coefficient for oral contraceptive use and pregnancies were 4.45 times and 12- to 15-fold greater than expected, respectively. LOY was associated with high-grade serous, low-grade serous, endometrioid, and clear cell histotypes (ORs per year increase = 1.054, 1.040, 1.065, and 1.098, respectively) but not mucinous tumors. Estimated coefficients of LOY components were close to expected estimates for high-grade serous but larger than expected for low-grade serous, endometrioid, and clear cell histotypes.

CONCLUSIONS

LOY is positively associated with nonmucinous EOC. Differences between estimated and expected model coefficients for LOY components suggest factors beyond ovulation underlie the associations between LOY components and EOC in general and for non-HGSOC.

Association of protein intake with recurrence and survival following primary treatment of ovarian cancer

BACKGROUND

Malnutrition is common during treatment for ovarian cancer and one in three report multiple symptoms affecting food intake after primary treatment. Little is known about diet post-treatment in relation to ovarian cancer survival, however, general recommendations for cancer survivors are to maintain a higher level of protein intake to support recovery and minimize nutritional deficits.

OBJECTIVE

To investigate whether intake of protein and protein food sources following primary treatment for ovarian cancer is associated with recurrence and survival.

DESIGN

Intake levels of protein and protein food groups were calculated from dietary data collected about 12 months post-diagnosis using a validated food frequency questionnaire in an Australian cohort of females with invasive epithelial ovarian cancer. Disease recurrence and survival status were abstracted from medical records (median 4.9 years follow-up). Cox proportional hazards regression was used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for protein intake and progression-free and overall survival.

RESULTS

Among 591 females who were progression-free at 12-months follow-up, 329 (56%) subsequently experienced cancer recurrence and 231 (39%) died. A higher level of protein intake was associated with better progression-free survival (>1-1.5 vs. ≤1 grams per kilogram body weight (g/kg): HR_adjusted=0.69, 95% CI 0.48, 1.00; >1.5 vs. ≤1g/kg: HR_adjusted=0.61, 95% CI 0.41, 0.90; >20% vs. ≤20% total energy intake from protein: HR_adjusted=0.77, 95% CI 0.61, 0.96). There was no evidence for better progression-free survival with any particular protein food sources. There was a suggestion of better overall survival among those with higher total intakes of animal-based protein foods, particularly dairy products (HR=0.71, 95% CI 0.51, 0.99 for highest vs. lowest tertiles of total dairy intake).

CONCLUSIONS

After primary treatment for ovarian cancer, a higher level of protein intake may benefit progression-free survival. Ovarian cancer survivors should avoid dietary practices that limit intake of protein-rich foods.

Clinical parameters affecting survival outcomes in patients with low-grade serous ovarian carcinoma: an international multicentre analysis

BACKGROUND

Women with low-grade ovarian serous carcinoma (LGSC) benefit from surgical treatment; however, the role of chemotherapy is controversial. We examined an international database through the Ovarian Cancer Association Consortium to identify factors that affect survival in LGSC.

METHODS

We performed a retrospective cohort analysis of patients with LGSC who had had primary surgery and had overall survival data available. We performed univariate and multivariate analyses of progression-free survival and overall survival, and generated Kaplan-Meier survival curves.

RESULTS

Of the 707 patients with LGSC, 680 (96.2%) had available overall survival data. The patients' median age overall was 54 years. Of the 659 patients with International Federation of Obstetrics and Gynecology stage data, 156 (23.7%) had stage I disease, 64 (9.7%) had stage II, 395 (59.9%) had stage III, and 44 (6.7%) had stage IV. Of the 377 patients with surgical data, 200 (53.0%) had no visible residual disease. Of the 361 patients with chemotherapy data, 330 (91.4%) received first-line platinum-based chemotherapy. The median follow-up duration was 5.0 years. The median progression-free survival and overall survival were 43.2 months and 110.4 months, respectively. Multivariate analysis indicated a statistically significant impact of stage and residual disease on progression-free survival and overall survival. Platinum-based chemotherapy was not associated with a survival advantage.

CONCLUSION

This multicentre analysis indicates that complete surgical cytoreduction to no visible residual disease has the most impact on improved survival in LGSC. This finding could immediately inform and change practice.

Associations of life course obesity with endometrial cancer in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

Adult obesity is a strong risk factor for endometrial cancer (EC); however, associations of early life obesity with EC are inconclusive. We evaluated associations of young adulthood (18-21 years) and adulthood (at enrolment) body mass index (BMI) and weight change with EC risk in the Epidemiology of Endometrial Cancer Consortium (E2C2).

METHODS

We pooled data from nine case-control and 11 cohort studies in E2C2. We performed multivariable logistic regression analyses to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for BMI (kg/m2) in young adulthood and adulthood, with adjustment for BMI in adulthood and young adulthood, respectively. We evaluated categorical changes in weight (5-kg increments) and BMI from young adulthood to adulthood, and stratified analyses by histology, menopausal status, race and ethnicity, hormone replacement therapy (HRT) use and diabetes.

RESULTS

We included 14 859 cases and 40 859 controls. Obesity in adulthood (OR = 2.85, 95% CI = 2.47-3.29) and young adulthood (OR = 1.26, 95% CI = 1.06-1.50) were positively associated with EC risk. Weight gain and BMI gain were positively associated with EC; weight loss was inversely associated with EC. Young adulthood obesity was more strongly associated with EC among cases diagnosed with endometrioid histology, those who were pre/perimenopausal, non-Hispanic White and non-Hispanic Black, among never HRT users and non-diabetics.

CONCLUSIONS

Young adulthood obesity is associated with EC risk, even after accounting for BMI in adulthood. Weight gain is also associated with EC risk, whereas weight loss is inversely associated. Achieving and maintaining a healthy weight over the life course is important for EC prevention efforts.

The effect of monthly vitamin D supplementation on fractures: a tertiary outcome from the population-based, double-blind, randomised, placebo-controlled D-Health trial

BACKGROUND

Low serum 25-hydroxy vitamin D concentration is associated with increased fracture risk. It is uncertain whether vitamin D supplementation reduces fractures, or whether intermittent doses are harmful. We aimed to investigate if supplementing adults living in Australia with monthly doses of 60 000 international units (IU) vitamin D₃ for 5 years or less altered the rate of fractures.

METHODS

We did a population-based, double-blind, randomised, placebo-controlled trial of oral vitamin D₃ supplementation (60 000 IU per month) for up to 5 years in adults aged 60-84 years living in Australia. We randomly assigned (1:1) 21 315 participants to either vitamin D or placebo. We ascertained fractures through linkage with administrative datasets. The main outcome was total fractures. Additional outcomes were non-vertebral, major osteoporotic (hip, wrist, proximal humerus, and spine), and hip fractures. We excluded participants (989 [4·6%]) without linked data, and estimated hazard ratios (HRs) and 95% CIs using flexible parametric survival models. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763, and the trial intervention ended in February, 2020.

FINDINGS

Between Feb 14, 2014, and June 17, 2015, we recruited 21 315 participants. For the current analysis, we included 20 326 participants (vitamin D 10 154 [50·0%]; placebo 10 172 [50·0%]). 9295 (45·7%) of 20 326 participants were women and the mean age was 69·3 years (SD 5·5). Over a median follow-up of 5·1 years (IQR 5·1-5·1), 568 (5·6%) participants in the vitamin D group and 603 (5·9%) in the placebo group had one or more fractures. There was no effect on fracture risk overall (HR 0·94 [95% CI 0·84-1·06]), and the interaction between randomisation group and time was not significant (p=0·14). However, the HR for total fractures appeared to decrease with increasing follow-up time. The overall HRs for non-vertebral, major osteoporotic, and hip fractures were 0·96 (95% CI 0·85-1·08), 1·00 (0·85-1·18), and 1·11 (0·86-1·45), respectively.

INTERPRETATION

These findings do not support concerns that bolus doses of vitamin D administered monthly increase fracture risk. Long-term supplementation might reduce the incidence of total fractures, but additional research is needed to clarify this effect.

FUNDING

Australian National Health and Medical Research Council.

Vitamin D Supplementation and the Incidence of Cataract Surgery in Older Australian Adults

PURPOSE

Observational studies suggest that higher serum 25-hydroxy vitamin D (25(OH)D) concentration may be associated with lower risk of cataract. However, no randomized controlled trials have assessed the effect of vitamin D supplementation on the incidence of cataract. We aimed to assess whether vitamin D supplementation reduces the incidence of cataract surgery.

DESIGN

We conducted an ancillary study of the D-Health Trial, a randomized, double-masked, placebo-controlled trial of monthly vitamin D conducted from 2014 through 2020 within the Australian general population.

PARTICIPANTS

We invited 421 207 men and women 60 to 84 years of age to participate; including an additional 1896 volunteers, 40 824 expressed interest. Those with hypercalcemia, hyperparathyroidism, kidney stones, osteomalacia, or sarcoidosis or those who were taking more than 500 international units (IU) supplemental vitamin D per day were excluded. A total of 21 315 were randomized, and 1390 participants did not fulfil the eligibility criteria for this analysis (linked data available, no cataract within first 6 months), leaving 19 925 included. The median follow-up was 5 years.

METHODS

Participants took 60 000 IU of vitamin D₃ (n = 10 662) or placebo (n = 10 653) orally once per month for a maximum of 5 years.

MAIN OUTCOME MEASURES

The primary outcome for this analysis was the first surgical treatment for cataract, ascertained through linkage to universal health insurance records and hospital data.

RESULTS

Among 19 925 participants eligible for this analysis (mean age, 69.3 years; 46% women) 3668 participants (18.4%) underwent cataract surgery during follow-up (vitamin D: n = 1841 [18.5%]; placebo: n = 1827 [18.3%] ). The incidence of cataract surgery was similar between the two groups (incidence rate, 41.6 and 41.1 per 1000 person-years in the vitamin D and placebo groups, respectively; hazard ratio, 1.02; 95% confidence interval, 0.95-1.09). In prespecified subgroup analyses, the effect of vitamin D supplementation on the incidence of cataract surgery was not modified by age, sex, body mass index, predicted serum 25(OH)D concentration, or ambient ultraviolet radiation.

CONCLUSIONS

Routinely supplementing older adults who live in an area with a low prevalence of vitamin D deficiency with high-dose vitamin D is unlikely to reduce the need for cataract surgery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Common analgesics and ovarian cancer survival: the Ovarian cancer Prognosis And Lifestyle (OPAL) Study

BACKGROUND

Most women with ovarian cancer (OC) are diagnosed with advanced disease. They often experience recurrence after primary treatment, and their subsequent prognosis is poor. Our goal was to evaluate the association between use of nonsteroidal antiinflammatory drugs (NSAIDs), including regular and low-dose aspirin, and 5-year cancer-specific survival after an OC diagnosis.

METHODS

The Ovarian cancer Prognosis And Lifestyle study is a prospective population-based cohort of 958 Australian women with OC. Information was gathered through self-completed questionnaires. We classified NSAID use during the year prediagnosis and postdiagnosis as none or occasional (<1 d/wk), infrequent (1-3 d/wk), and frequent (≥4 d/wk) use. We measured survival from the start of primary treatment: surgery or neoadjuvant chemotherapy for analyses of prediagnosis use, or 12 months after starting treatment (postdiagnosis use) until the earliest of date of death from OC (other deaths were censored) or last follow-up to 5 years. We used Cox proportional hazards regression to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) and applied inverse-probability of treatment weighting to minimize confounding. We also calculated restricted mean survival times.

RESULTS

Compared with nonusers and infrequent users, we observed better survival associated with frequent NSAID use prediagnosis (HR = 0.73, 95% CI = 0.55 to 0.97) or postdiagnosis (HR = 0.65, 95% CI = 0.45 to 0.94). Estimates were similar for aspirin and nonaspirin NSAIDs, new and continuous users and in weighted models. These differences would translate to a 2.5-month increase in mean survival by 5 years postdiagnosis. There was no association with acetaminophen.

CONCLUSIONS

Our findings confirm a previous study suggesting NSAID use might improve OC survival.

Association of Frequent Aspirin Use With Ovarian Cancer Risk According to Genetic Susceptibility

Importance

Frequent aspirin use is associated with reduced ovarian cancer risk, but it is unknown whether genetic factors modify this association. Understanding effect modifiers is important given that any use of aspirin for ovarian cancer chemoprevention will likely need to focus on specific higher-risk subgroups.

Objective

To evaluate whether the association between frequent aspirin use and ovarian cancer is modified by a polygenic score (PGS) for nonmucinous ovarian cancer.

Design, Setting, and Participants

We pooled individual-level data from 8 population-based case-control studies from the Ovarian Cancer Association Consortium conducted in the US, UK, and Australia between 1995 and 2009. We included case patients and control participants with both genetic data and data on frequent aspirin use. Case patients with mucinous ovarian cancer were excluded. Data were analyzed between November 1, 2021, and July 31, 2022.

Exposures

Frequent aspirin use, defined as daily or almost daily use for 6 months or longer.

Main Outcomes and Measures

The main outcome was nonmucinous epithelial ovarian cancer. We used logistic regression to estimate odds ratios (ORs) and 95% CIs and likelihood ratio tests to investigate effect modification by the PGS.

Results

There were 4476 case patients with nonmucinous ovarian cancer and 6659 control participants included in this analysis. At study enrollment, the median (IQR) age was 58 (50-66) years for case patients and 57 (49-65) years for control participants. Case patients and control participants self-reported that they were Black (122 [3%] vs 218 [3%]), White (3995 [89%] vs 5851 [88%]), or of other race and ethnicity (348 [8%] vs 580 [9%]; race and ethnicity were unknown for 11 [0%] vs 10 [0%]). There were 575 case patients (13%) and 1030 control participants (15%) who reported frequent aspirin use. The 13% reduction in ovarian cancer risk associated with frequent aspirin use (OR, 0.87 [95% CI, 0.76-0.99]) was not modified by the PGS. Consistent ORs were observed among individuals with a PGS less than (0.85 [0.70-1.02]) and greater than (0.86 [0.74-1.01]) the median. Results were similar by histotype.

Conclusions and Relevance

The findings of this study suggest that genetic susceptibility to ovarian cancer based on currently identified common genetic variants does not appear to modify the protective association between frequent aspirin use and ovarian cancer risk. Future work should continue to explore the role of aspirin use for ovarian cancer prevention among individuals who are at higher risk for ovarian cancer.

Dietary omega-3 fatty acids and endometrial cancer risk in the Epidemiology of Endometrial Cancer Consortium: An individual-participant meta-analysis

BACKGROUND

Limited data from prospective studies suggest that higher dietary intake of long-chain omega-3 polyunsaturated fatty acids (LCn3PUFA), which hold anti-inflammatory properties, may reduce endometrial cancer risk; particularly among certain subgroups characterized by body mass and tumor pathology.

MATERIALS AND METHODS

Data from 12 prospective cohort studies participating in the Epidemiology of Endometrial Cancer Consortium were harmonized as nested case-control studies, including 7268 endometrial cancer cases and 26,133 controls. Habitual diet was assessed by food frequency questionnaire, from which fatty acid intakes were estimated. Two-stage individual-participant data mixed effects meta-analysis estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) through logistic regression for associations between study-specific energy-adjusted quartiles of LCn3PUFA and endometrial cancer risk.

RESULTS

Women with the highest versus lowest estimated dietary intakes of docosahexaenoic acid, the most abundant LCn3PUFA in diet, had a 9% increased endometrial cancer risk (Quartile 4 vs. Quartile 1: OR 1.09, 95% CI: 1.01-1.19; P trend = 0.04). Similar elevated risks were observed for the summary measure of total LCn3PUFA (OR 1.07, 95% CI: 0.99-1.16; P trend = 0.06). Stratified by body mass index, higher intakes of LCn3PUFA were associated with 12-19% increased endometrial cancer risk among overweight/obese women and no increased risk among normal-weight women. Higher associations appeared restricted to White women. The results did not differ by cancer grade.

CONCLUSION

Higher dietary intakes of LCn3PUFA are unlikely to reduce endometrial cancer incidence; rather, they may be associated with small to moderate increases in risk in some subgroups of women, particularly overweight/obese women.

Vitamin D supplementation and hospitalization for infection in older adults: A post-hoc analysis of data from the Australian D-Health Trial

BACKGROUND

Evidence suggests that vitamin D influences the immune system. Recent studies indicate that vitamin D supplementation may reduce the severity of infections, but this has not been confirmed.

OBJECTIVES

The objective of this study was to assess the effect of vitamin D supplementation on hospitalization for infection.

METHODS

The D-Health Trial was a randomized, double-blind, placebo-controlled trial of monthly 60,000 international units of vitamin D₃ for 5 y among 21,315 Australians aged 60-84 y. Hospitalization for infection, ascertained through linkage with hospital admitted patient data, is a tertiary outcome of the trial. The primary outcome for this post-hoc analysis was hospitalization for any infection. Secondary outcomes were extended hospitalization for infection (length of stay >3 d and >6 d) and hospitalization for respiratory tract, skin, and gastrointestinal infections. We used negative binomial regression to estimate the effect of vitamin D supplementation on outcomes.

RESULTS

Participants (46% women, mean age: 69 y), were followed up for a median of 5 y. Vitamin D supplementation had little or no effect on the incidence of hospitalization for any infection [incidence rate ratio (IRR): 0.95; 95% CI: 0.86, 1.05], respiratory tract (IRR: 0.93; 95% CI: 0.81, 1.08), skin (IRR: 0.95; 95% CI: 0.76, 1.20), gastrointestinal infections (IRR: 1.03; 95% CI: 0.84, 1.26), or hospitalizations lasting >3 d (IRR: 0.94; 95% CI: 0.81, 1.09), with all CIs consistent with a null finding. People supplemented with vitamin D had fewer hospitalizations lasting >6 d (IRR: 0.80; 95% CI: 0.65, 0.99).

CONCLUSIONS

We did not find a protective effect of vitamin D on hospitalization for infection, but it reduced the number of extended hospitalizations. In populations where few people are vitamin D deficient, the effect of population-wide supplementation is likely to be small, but these findings support previous studies suggesting that vitamin D plays a role in infectious disease. The D-Health Trial is registered at the Australian New Zealand Clinical Trials Registry as ACTRN12613000743763.

Effects of Vitamin D Supplementation on Telomere Length: An Analysis of Data from the Randomised Controlled D-Health Trial

OBJECTIVES

Observational studies have suggested that a higher 25-hydroxyvitamin D concentration may be associated with longer telomere length; however, this has not been investigated in randomised controlled trials. We conducted an ancillary study within a randomised, double-blind, placebo-controlled trial of monthly vitamin D (the D-Health Trial) for the prevention of all-cause mortality, conducted from 2014 to 2020, to assess the effect of vitamin D supplementation on telomere length (measured as the telomere to single copy gene (T/S) ratio).

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION

Participants were Australians aged 60-84 years and we randomly selected 1,519 D-Health participants (vitamin D: n=744; placebo: n=775) for this analysis. We used quantitative polymerase chain reaction to measure the relative telomere length (T/S ratio) at 4 or 5 years after randomisation. We compared the mean T/S ratio between the vitamin D and placebo groups to assess the effect of vitamin D supplementation on relative telomere length, using a linear regression model with adjustment for age, sex, and state which were used to stratify the randomisation.

RESULTS

The mean T/S ratio was 0.70 for both groups (standard deviation 0.18 and 0.16 for the vitamin D and placebo groups respectively). The adjusted mean difference (vitamin D minus placebo) was -0.001 (95% CI -0.02 to 0.02). There was no effect modification by age, sex, body mass index, or predicted baseline 25-hydroxyvitamin D concentration.

CONCLUSION

In conclusion, routinely supplementing older adults, who are largely vitamin D replete, with monthly doses of vitamin D is unlikely to influence telomere length.

Healthcare Costs Before and After Diagnosis of Cancer of Unknown Primary Versus Ovarian Cancer in Australia

BACKGROUND

Little is known about the healthcare resource usage and costs for patients with cancer of unknown primary (CUP).

OBJECTIVE

The aim of this study was to describe and quantify healthcare resource use and costs in Australia, 6 months prior to and after a diagnosis of CUP, and compare to those of women with ovarian cancer.

METHODS

Individual-level data combining baseline surveys, clinical records and Medicare Benefits Schedule (MBS) claim records were analysed for 149 patients with CUP and 480 patients with ovarian cancer from two prospective cohort studies. MBS data were aggregated for the period 6 months prior to diagnosis date and 6 months after diagnosis. Data included doctor consultations, pathology, diagnostics, therapeutic procedures, imaging, allied health and medicines. Generalised linear models were used to evaluate the cost differences between CUP and ovarian cancer using gamma family and log link functions. Models were adjusted for age, employment, marital status, surgery, chemotherapy and number of comorbidities.

RESULTS

The mean healthcare costs in the 6 months prior to diagnosis of CUP were Australian (AU) $3903 versus AU$1327 for ovarian cancer (adjusted cost ratio 2.94, 95% confidence interval [CI] 2.08-4.15). Mean healthcare costs 6 months post-diagnosis were higher for patients with CUP versus ovarian cancer (AU$20,339 vs AU$13,819, adjusted cost ratio 1.47, 95% CI 1.13-1.92). Higher costs for patients with CUP were driven by imaging (AU$1937 vs AU$1387), procedures (AU$5403 vs AU$2702) and prescribed medicines for all conditions (AU$10,111 vs AU$6717).

CONCLUSIONS

Pre-diagnosis costs for patients with CUP are nearly triple those for ovarian cancer. Six months after diagnosis, healthcare costs for CUP remained higher than for ovarian cancer due to imaging, procedures and medicines.

Health services costs for ovarian cancer in Australia: Estimates from the 45 and Up Study

INTRODUCTION

There have been significant advancements in risk identification and treatment for ovarian cancer over the last decade. However, their impact on health services costs is unclear. This study estimated the direct health system costs (government perspective) for women diagnosed with ovarian cancer in Australia during 2006-2013, as a benchmark prior to opportunities for precision-medicine approaches to treatment, and for health care planning.

METHODS

Using cancer registry data, we identified 176 incident ovarian cancers (including fallopian tube and primary peritoneal cancer) in the Australian 45 and Up Study cohort. Each case was matched with four cancer-free controls on sex, age, geography, and smoking history. Costs were derived from linked health records on hospitalisations, subsidised prescription medicines and medical services to 2016. Excess costs for cancer cases were estimated for different phases of care relative to cancer diagnosis. Overall costs for prevalent ovarian cancers in Australia in 2013 were estimated based on 5-year prevalence statistics.

RESULTS

At diagnosis, 10% of women had localised disease, 15% regional spread and 70% distant metastasis (5% unknown). The mean excess cost per ovarian cancer case was $40,556 in the initial treatment phase (≤12 months post-diagnosis), $9,514 per annum in the continuing care phase and $49,208 in the terminal phase (up to 12 months before death). Hospital admissions accounted for the greatest proportion of costs during all phases (66%, 52% and 68% respectively). Excess costs were higher for patients diagnosed with distant metastatic disease, particularly during the continuing care phase ($13,814 versus $4,884 for localised/regional disease). The estimated overall direct health services cost of ovarian cancer in 2013 was AUD$99million (4,700 women nationally).

CONCLUSION

The excess health system costs of ovarian cancer are substantial. Continued investment in ovarian cancer research, particularly prevention, early detection and more effective personalised treatments is necessary to reduce the burden of disease.

Lifestyle and personal factors associated with having macroscopic residual disease after ovarian cancer primary cytoreductive surgery

OBJECTIVE

The presence of macroscopic residual disease after primary cytoreductive surgery (PCS) is an important factor influencing survival for patients with high-grade serous ovarian cancer (HGSC). More research is needed to identify factors associated with having macroscopic residual disease. We analyzed 12 lifestyle and personal exposures known to be related to ovarian cancer risk or inflammation to identify those associated with having residual disease after surgery.

METHODS

This analysis used data on 2054 patients with advanced stage HGSC from the Ovarian Cancer Association Consortium. The exposures were body mass index, breastfeeding, oral contraceptive use, depot-medroxyprogesterone acetate use, endometriosis, first-degree family history of ovarian cancer, incomplete pregnancy, menopausal hormone therapy use, menopausal status, parity, smoking, and tubal ligation. Logistic regression models were fit to assess the association between these exposures and having residual disease following PCS.

RESULTS

Menopausal estrogen-only therapy (ET) use was associated with 33% lower odds of having macroscopic residual disease compared to never use (OR = 0.67, 95%CI 0.46-0.97, p = 0.033). Compared to nulliparous women, parous women who did not breastfeed had 36% lower odds of having residual disease (OR = 0.64, 95%CI 0.43-0.94, p = 0.022), while there was no association among parous women who breastfed (OR = 0.90, 95%CI 0.65-1.25, p = 0.53).

CONCLUSIONS

The association between ET and having no macroscopic residual disease is plausible given a strong underlying biologic hypothesis between this exposure and diagnosis with HGSC. If this or the parity finding is replicated, these factors could be included in risk stratification models to determine whether HGSC patients should receive PCS or neoadjuvant chemotherapy.

The effect of vitamin D supplementation on the gut microbiome in older Australians - Results from analyses of the D-Health Trial

Observational studies suggest a link between vitamin D and the composition of the gut microbiome, but there is little evidence from randomized controlled trials of vitamin D supplementation. We analyzed data from the D-Health Trial, a randomized, double-blind, placebo-controlled trial. We recruited 21,315 Australians aged 60-84 y and randomized them to 60,000 IU of vitamin D₃ or placebo monthly for 5 y. Stool samples were collected from a sample of 835 participants (417 in the placebo and 418 in the vitamin D group) approximately 5 y after randomization. We characterized the gut microbiome using 16S rRNA gene sequencing. We used linear regression to compare alpha diversity indices (i.e. Shannon index (primary outcome), richness, inverse Simpson index), and the ratio of Firmicutes to Bacteroidetes between the two groups. We analyzed between-sample (beta) diversity (i.e. Bray Curtis distance and UniFrac index) using principal coordinate analysis and used PERMANOVA to test for significant clustering according to randomization group. We also assessed the difference in the abundance of the 20 most abundant genera between the two groups using negative binomial regression model with adjustment for multiple testing. Approximately half the participants included in this analysis were women (mean age 69.4 y). Vitamin D supplementation did not alter the Shannon diversity index (mean 3.51 versus 3.52 in the placebo and vitamin D groups, respectively, p = 0.50). Similarly, there was little difference between the groups for other alpha diversity indices, the abundance of different genera, and the Firmicutes-to-Bacteroidetes ratio. We did not observe clustering of bacterial communities according to randomization group. In conlusion, monthly doses of 60,000 IU of vitamin D supplementation for 5 y did not alter the composition of the gut microbiome in older Australians.

Effect of vitamin D supplementation on depression in older Australian adults

OBJECTIVES

To investigate whether vitamin D supplementation reduces depressive symptoms and incidence of antidepressant use.

METHODS

We used data from the D-Health Trial (N = 21,315), a randomized double-blind placebo-controlled trial of monthly vitamin D₃ for the prevention of all-cause mortality. Participants were Australians aged 60-84 years. Participants completed the Patient Health Questionnaire (PHQ-9) at 1, 2 and 5 years after randomization to measure depressive symptoms; national prescribing records were used to capture antidepressant use. We used mixed models and survival models.

RESULTS

Analyses of PHQ-9 scores included 20,487 participants (mean age 69·3 years, 46% women); the mean difference (MD) in PHQ-9 score (vitamin D vs. placebo) was 0·02 (95% CI -0·06, 0·11). There was negligible difference in the prevalence of clinically relevant depression (PHQ-9 score ≥10) (odds ratio 0·99; 95% CI 0·90, 1·08). We included 16,670 participants in the analyses of incident antidepressant use (mean age 69·4 years, 43% women). Incidence of antidepressant use was similar between the groups (hazard ratio [HR] 1·04; 95% CI 0·96, 1·12). In subgroup analyses, vitamin D improved PHQ-9 scores in those taking antidepressants at baseline (MD -0·25; 95% CI -0·49, -0·01; p-interaction = 0·02). It decreased risk of antidepressant use in participants with predicted 25(OH)D concentration <50 nmol/L (HR 0·88; 95% CI 0·75, 1·02; p-interaction = 0·01) and increased risk in those with predicted 25(OH)D ≥ 50 nmol/L (HR 1·10; 95% CI 1·01, 1·20).

CONCLUSION

Monthly supplementation with high-dose vitamin D₃ was not of benefit for measures of depression overall, but there was some evidence of benefit in subgroup analyses.

CLINICAL TRIAL REGISTRATION

The trial is registered on the Australian New Zealand Clinical Trials Registry: ACTRN12613000743763. https://www.anzctr.org.au/.

Modification of the Association Between Frequent Aspirin Use and Ovarian Cancer Risk: A Meta-Analysis Using Individual-Level Data From Two Ovarian Cancer Consortia

PURPOSE

Frequent aspirin use has been associated with reduced ovarian cancer risk, but no study has comprehensively assessed for effect modification. We leveraged harmonized, individual-level data from 17 studies to examine the association between frequent aspirin use and ovarian cancer risk, overall and across subgroups of women with other ovarian cancer risk factors.

METHODS

Nine cohort studies from the Ovarian Cancer Cohort Consortium (n = 2,600 cases) and eight case-control studies from the Ovarian Cancer Association Consortium (n = 5,726 cases) were included. We used Cox regression and logistic regression to assess study-specific associations between frequent aspirin use (≥ 6 days/week) and ovarian cancer risk and combined study-specific estimates using random-effects meta-analysis. We conducted analyses within subgroups defined by individual ovarian cancer risk factors (endometriosis, obesity, family history of breast/ovarian cancer, nulliparity, oral contraceptive use, and tubal ligation) and by number of risk factors (0, 1, and ≥ 2).

RESULTS

Overall, frequent aspirin use was associated with a 13% reduction in ovarian cancer risk (95% CI, 6 to 20), with no significant heterogeneity by study design (P = .48) or histotype (P = .60). Although no association was observed among women with endometriosis, consistent risk reductions were observed among all other subgroups defined by ovarian cancer risk factors (relative risks ranging from 0.79 to 0.93, all P-heterogeneity > .05), including women with ≥ 2 risk factors (relative risk, 0.81; 95% CI, 0.73 to 0.90).

CONCLUSION

This study, the largest to-date on aspirin use and ovarian cancer, provides evidence that frequent aspirin use is associated with lower ovarian cancer risk regardless of the presence of most other ovarian cancer risk factors. Risk reductions were also observed among women with multiple risk factors, providing proof of principle that chemoprevention programs with frequent aspirin use could target higher-risk subgroups.

The association between diabetes mellitus of different durations and risk of pancreatic cancer: an Australian national data-linkage study in women

AIMS

The bidirectional association between diabetes mellitus (DM) and pancreatic cancer (PC) is established; however, the strength of association between duration of DM and risk of PC needs further investigation.

METHODS

We conducted a case-control study nested within a population-based cohort of Australian women established using record linkage. Women diagnosed with PC from July 2007 to December 2013, were matched to five controls based on age and state of residence. DM was defined according to prescription of anti-diabetic medication from administrative prescription data. We used conditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI), adjusted for area-level socioeconomic status, rurality of residence, weighted comorbidity score, and predicted probability of obesity.

RESULTS

The analyses included 7,267 cases and 35,978 controls. The mean age at the time of DM diagnosis was 71 years whereas the mean age at the time of diagnosis of PC was 76 years. A history of DM of any duration was associated with a 2-fold increase in risk of PC (OR=2.12; 95%CI:1.96-2.29) compared to having no history of DM. The risk decreased with increasing duration of DM. The highest risk was in those who had recent-onset DM (OR=8.08; 95%CI:6.88-9.50 for <12 months of DM), but the risk remained elevated with ≥5 years of DM (OR=1.40; 95%CI:1.27-1.55).

CONCLUSION

The markedly increased risk of PC in those with recent-onset DM emphasises the need for further research to distinguish patients for whom new-onset DM is a manifestation of PC from those with type-2 DM. The elevated risk associated with long-standing DM suggests that preventing DM may contribute to a reduction in the incidence of PC.

Copy Number Variants Are Ovarian Cancer Risk Alleles at Known and Novel Risk Loci

BACKGROUND

Known risk alleles for epithelial ovarian cancer (EOC) account for approximately 40% of the heritability for EOC. Copy number variants (CNVs) have not been investigated as EOC risk alleles in a large population cohort.

METHODS

Single nucleotide polymorphism array data from 13 071 EOC cases and 17 306 controls of White European ancestry were used to identify CNVs associated with EOC risk using a rare admixture maximum likelihood test for gene burden and a by-probe ratio test. We performed enrichment analysis of CNVs at known EOC risk loci and functional biofeatures in ovarian cancer-related cell types.

RESULTS

We identified statistically significant risk associations with CNVs at known EOC risk genes; BRCA1 (PEOC = 1.60E-21; OREOC = 8.24), RAD51C (Phigh-grade serous ovarian cancer [HGSOC] = 5.5E-4; odds ratio [OR]HGSOC = 5.74 del), and BRCA2 (PHGSOC = 7.0E-4; ORHGSOC = 3.31 deletion). Four suggestive associations (P < .001) were identified for rare CNVs. Risk-associated CNVs were enriched (P < .05) at known EOC risk loci identified by genome-wide association study. Noncoding CNVs were enriched in active promoters and insulators in EOC-related cell types.

CONCLUSIONS

CNVs in BRCA1 have been previously reported in smaller studies, but their observed frequency in this large population-based cohort, along with the CNVs observed at BRCA2 and RAD51C gene loci in EOC cases, suggests that these CNVs are potentially pathogenic and may contribute to the spectrum of disease-causing mutations in these genes. CNVs are likely to occur in a wider set of susceptibility regions, with potential implications for clinical genetic testing and disease prevention.

Effects of risk factors for ovarian cancer in women with and without endometriosis

OBJECTIVE

To evaluate the associations between 10 well-established ovarian cancer risk factors and risk of ovarian cancer among women with vs. without endometriosis.

DESIGN

Pooled analysis of 9 case-control studies in the Ovarian Cancer Association Consortium.

SETTING

Population-based.

PATIENT(S)

We included 8,500 women with ovarian cancer, 13,592 control women.

INTERVENTION(S)

Ten well-established ovarian cancer risk factors.

MAIN OUTCOME MEASURE(S)

Risk of ovarian cancer for women with and without endometriosis.

RESULT(S)

Most risk factor-ovarian cancer associations were similar when comparing women with and without endometriosis, and no interactions were statistically significant. However, body mass index (BMI) 25-<30 kg/m² was associated with increased ovarian cancer risk among women with endometriosis (odds ratio [OR] = 1.27, 95% confidence interval [CI] 1.00-1.60), but not associated with the risk among women without endometriosis (OR = 0.97; 95% CI, 0.91-1.05) when compared with BMI 18.5-<25 kg/m²; an increased risk was observed for a BMI ≥30 kg/m², although there was little difference comparing women with endometriosis (OR = 1.21; 95% CI, 0.94-1.57) to women without (OR = 1.13; 95% CI, 1.04-1.22) (P-interaction = .51). Genital talcum powder use and long-term menopausal estrogen-only therapy use showed increased ovarian cancer risk, but risk appeared greater for those with endometriosis vs. those without (genital talcum powder: OR = 1.38; 95% CI, 1.04-1.84 vs. OR = 1.12; 95% CI, 1.01-1.25, respectively; ≥10 years of estrogen-only therapy: OR = 1.88; 95% CI, 1.09-3.24 vs. OR = 1.42; 95% CI, 1.14-1.76, respectively); neither of these interactions were statistically significant (P-interaction = .65 and P-interaction = .96, respectively).

CONCLUSION(S)

The associations between ovarian cancer and most risk factors were similar among women with and without endometriosis. However, there was some suggestion of differences by endometriosis status for BMI, menopausal hormone therapy use, and genital talcum powder use, highlighting the complexity of ovarian cancer etiology.

Coffee consumption and risk of endometrial cancer: a pooled analysis of individual participant data in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

Epidemiologic studies suggest that coffee consumption may be inversely associated with risk of endometrial cancer (EC), the most common gynecological malignancy in developed countries. Furthermore, coffee consumption may lower circulating concentrations of estrogen and insulin, hormones implicated in endometrial carcinogenesis. Antioxidants and other chemopreventive compounds in coffee may have anticarcinogenic effects. Based on available meta-analyses, the World Cancer Research Fund (WCRF) concluded that consumption of coffee probably protects against EC.

OBJECTIVES

Our main aim was to examine the association between coffee consumption and EC risk by combining individual-level data in a pooled analysis. We also sought to evaluate potential effect modification by other risk factors for EC.

METHODS

We combined individual-level data from 19 epidemiologic studies (6 cohort, 13 case-control) of 12,159 EC cases and 27,479 controls from the Epidemiology of Endometrial Cancer Consortium (E2C2). Logistic regression was used to calculate ORs and their corresponding 95% CIs. All models were adjusted for potential confounders including age, race, BMI, smoking status, diabetes status, study design, and study site.

RESULTS

Coffee drinkers had a lower risk of EC than non-coffee drinkers (multiadjusted OR: 0.87; 95% CI: 0.79, 0.95). There was a dose-response relation between higher coffee consumption and lower risk of EC: compared with non-coffee drinkers, the adjusted pooled ORs for those who drank 1, 2-3, and >4 cups/d were 0.90 (95% CI: 0.82, 1.00), 0.86 (95% CI: 0.78, 0.95), and 0.76 (95% CI: 0.66, 0.87), respectively (P-trend < 0.001). The inverse association between coffee consumption and EC risk was stronger in participants with BMI > 25 kg/m2.

CONCLUSIONS

The results of the largest analysis to date pooling individual-level data further support the potentially beneficial health effects of coffee consumption in relation to EC, especially among females with higher BMI.

The effect of vitamin D supplementation on risk of keratinocyte cancer - an exploratory analysis of the D-Health Randomised Controlled Trial

BACKGROUND

Vitamin D may play a role in prevention of keratinocyte cancer (KC), but observational studies examining the association between serum 25-hydroxy vitamin D concentration and KC are largely uninformative because sun exposure causes both KC and vitamin D production. There is scant evidence from clinical trials of supplementary vitamin D.

OBJECTIVES

To examine the effect of vitamin D supplementation on the risk of developing KC.

METHODS

We used data from the D-Health Trial, a randomised placebo-controlled trial of vitamin D supplementation (60,000 IU monthly for 5 years) among Australians aged ≥60 years. KC outcomes were captured through linkage to a national administrative dataset for those who consented (N=20,334; 95%). We used negative binomial regression to analyse the incidence of KC excisions and the incidence of actinic lesions treated using cryotherapy or serial curettage, and flexible parametric survival models for analysis of time to first KC excision.

RESULTS

Randomisation to vitamin D supplementation did not reduce the incidence of KC lesions treated by excision [incidence rate ratio (IRR) 1.04; 95% CI 0.98 - 1.11], the incidence of actinic lesions treated using other methods (IRR 1.01; 95% CI 0.95 - 1.08), or time to first histologically confirmed KC excision (hazard ratio 1.02; 95% CI 0.97 - 1.08). However, in subgroup analysis vitamin D increased the incidence of KC excisions in adults aged ≥70 years (IRR 1.13; 95% CI 1.04-1.23. p-value for interaction 0.01).

CONCLUSION

Vitamin D supplementation did not reduce the incidence of KC or other actinic lesions.

Vitamin D supplementation and antibiotic use in older Australian adults - an analysis of data from the D-Health Trial

BACKGROUND

Vitamin D supplementation may reduce the risk or severity of infection, but this has been investigated in few large population-based trials. We analyzed data from the D-Health Trial, using prescription of antibiotics as a surrogate for infection.

METHODS

The D-Health Trial is a randomized, double-blind, placebo-controlled trial in which 21,315 Australians aged 60-84 years were randomized to 60,000 IU of supplementary vitamin D3 or placebo monthly for 5 years. For this analysis, the primary outcome was the number of antibiotic prescription episodes; secondary outcomes were total number of prescriptions; repeat prescription episodes; and antibiotics for urinary tract infection. We estimated incidence rate ratios (IRRs) using negative binomial regression, and odds ratios using logistic regression.

RESULTS

Vitamin D supplementation slightly reduced the number of prescription episodes (IRR 0.98, 95% CI 0.95-1.01), total prescriptions (IRR 0.97, 95% CI 0.93-1.00), and repeat prescription episodes (IRR 0.96, 95% CI 0.93-1.00). There was stronger evidence of benefit in people predicted to have insufficient vitamin D at baseline (prescription episodes IRR 0.93, 95% CI 0.87-0.99).

CONCLUSIONS

Vitamin D may reduce the number of antibiotic prescriptions, particularly in people with low vitamin D status. This supports the hypothesis that vitamin D has a clinically relevant effect on the immune system.

Abstract 736: Exploring the impact of infertility and its treatments on risk of ovarian cancer

Background: Infertility is related to both nulligravidity and endometriosis, which are both well-established risk factors for ovarian cancer. Infertility is also characterized by various underlying causes and can be treated with different types of fertility drugs. However, most studies to date have been unable to properly address these important issues when examining the infertility-ovarian cancer association due to small numbers of patients and a lack of detailed infertility and risk factor information.

Methods: We pooled self-reported data from 8,324 invasive, epithelial ovarian cancer cases and 13,325 control women in eight population-based case-control studies participating in the Ovarian Cancer Association Consortium (OCAC) to study the infertility-ovarian cancer relationship. Women classified as having a history of infertility were those who had spoken to a doctor about infertility problems or those who had regular sexual intercourse without birth control for a prolonged period (usually one year) without getting pregnant. Cause of infertility as well as use of fertility drugs was examined among those who experienced infertility issues. These associations with risk of ovarian cancer were evaluated using logistic regression models and quantified using odds ratios (ORs) and 95% confidence intervals (CIs). Gravidity and endometriosis were considered in the analyses as well as potential confounding factors.

Results: Overall, infertility was not associated with risk of ovarian cancer (OR=1.02, 95% CI 0.95-1.09). However, women who reported their infertility was due to problems with ovulation or menstruation showed a decreased risk (OR=0.72, 95% CI 0.52-1.01 and OR=0.62, 95% CI 0.43-0.91, respectively) whereas women who reported their infertility was due to endometriosis were at an increased risk (OR=1.54, 95% CI 1.19-1.98). Among women who reported infertility issues, use of fertility drugs was not associated with an increased risk of ovarian cancer regardless of their gravidity status (OR=0.89, 95% CI 0.76-1.05).

Conclusions: The relationship between infertility and risk of ovarian cancer is complex. Although infertility does not appear to be an independent risk factor for ovarian cancer, specific causes of infertility may be differentially associated with ovarian cancer risk, which may shed light on the disease’s underlying etiology. In addition, for women experiencing infertility issues, use of fertility drugs did not show an increased risk of ovarian cancer, which may have important clinical implications.

Citation Format: Alice W. Lee, Minh T. Phung, Allan Jensen, Anna H. Wu, Daniel W. Cramer, Francesmary Modugno, Holly Harris, Jennifer A. Doherty, Joellen Schildkraut, Kathryn L. Terry, Kirsten B. Moysich, Malcolm C. Pike, Marc T. Goodman, Penelope M. Webb, Susanne K. Kjaer, Celeste L. Pearce. Exploring the impact of infertility and its treatments on risk of ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 736.

Abstract 2248: Environmental factors associated with residual disease after ovarian cancer primary cytoreduction surgery

Background: Ovarian cancer is the deadliest gynecologic cancer. Standard treatments for advanced stage high-grade serous ovarian cancer, the most common type, include (1) primary cytoreductive surgery (PCS) followed by adjuvant chemotherapy or (2) neoadjuvant chemotherapy (NACT) with interval debulking surgery. Patients in whom PCS is unlikely to yield optimal cytoreduction to no visible residual disease (R0) or who have medical contraindications to PCS are recommended to undergo NACT. Previous studies on associations between environmental factors and risk of any macroscopic residual disease have yielded inconsistent results. We aimed to (1) comprehensively examine the associations between demographic, lifestyle and reproductive factors and risk of residual disease after PCS; and (2) develop and internally validate a risk prediction model based on these factors.

Methods: We used pooled data on 3,492 women who had PCS following a diagnosis with advanced stage high-grade serous ovarian, fallopian tube or primary peritoneal cancers from the Ovarian Cancer Association Consortium. Fifteen exposures of interest included age at diagnosis, menopausal status, race/ethnicity, education level, first-degree family history of ovarian cancer, endometriosis, smoking, body mass index, parity, incomplete pregnancy, tubal ligation, use of combined oral contraceptives, depot-medroxyprogesterone acetate, estrogen (ET), and combined estrogen-progestin therapy. We fit logistic regression models to examine each exposure-residual disease association in 80% of the data (n=2,794; random selection of participants). We developed a risk prediction model including the factors with p-values ≤0.2. Area under the receiver operating characteristic curve (AUC) was used to assess the model’s discrimination in the remaining 20% of the data (n=698).

Results: Of the 3,492 participants, 2,003 (57%) had residual disease following PCS. Older age at diagnosis was associated with an increased risk of residual disease (OR=1.07 per five years, 95% CI 1.03-1.11). In contrast, a family history of ovarian cancer (OR=0.63, 95% CI 0.42-0.95) or ET use for 5+ years (OR=0.61, 95% CI 0.39-0.96) were associated with achieving R0. These above factors were included in the risk prediction model as were race/ethnicity, personal history of endometriosis, and smoking, whose p-values ≤0.2. The model showed modest performance in the validation set (AUC=0.64).

Conclusions: Younger age at diagnosis, family history of ovarian cancer, and long-term ET use were associated with achieving R0 following PCS. Future studies incorporating genetic and clinical factors to improve the risk prediction for residual disease following PCS are warranted.

Citation Format: Minh Tung Phung, Andrew Berchuck, Ellen L. Goode, Marc T. Goodman, Gillian E. Hanley, Jean Richardson, Bronwyn Grout, Anne Chase, Cindy McKinnon Deurloo, Beth Y. Karlan, Toon Van Gorp, Keitaro Matsuo, Karen McLean, Malcolm C. Pike, Joellen M. Schildkraut, Kathryn L. Terry, Anna DeFazio, Penelope M. Webb, Paul D. P. Pharoah, Susan J. Ramus, Celeste Leigh Pearce. Environmental factors associated with residual disease after ovarian cancer primary cytoreduction surgery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2248.

Germline BRCA variants, lifestyle and ovarian cancer survival

OBJECTIVE

Women with ovarian cancer who have a pathogenic germline variant in BRCA1 or BRCA2 (BRCA) have been shown to have better 5-year survival after diagnosis than women who are BRCA-wildtype (non-carriers). Modifiable lifestyle factors, including smoking, physical activity and body mass index (BMI) have previously been associated with ovarian cancer survival; however, it is unknown whether these associations differ by germline BRCA status.

METHODS

We investigated measures of lifestyle prior to diagnosis in two cohorts of Australian women with invasive epithelial ovarian cancer, using Cox proportional hazards regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

In the combined studies (n = 1923), there was little association between physical activity, BMI or alcohol intake and survival, and no difference by BRCA status. However, the association between current smoking status before diagnosis and poorer survival was stronger for BRCA variant carriers (HR 1.98; 95% CI 1.20-3.27) than non-carriers (HR 1.18; 95% CI 0.96-1.46; p-interaction 0.02). We saw a similar differential association with smoking when we pooled results from two additional cohorts from the USA and UK (n = 2120). Combining the results from all four studies gave a pooled-HR of 1.94 (95% CI 1.28-2.94) for current smoking among BRCA variant carriers compared to 1.08 (0.90-1.29) for non-carriers.

CONCLUSIONS

Our results suggest that the adverse effect of smoking on survival may be stronger for women with a BRCA variant than those without. Thus, while smoking cessation may improve outcomes for all women with ovarian cancer, it might provide a greater benefit for BRCA variant carriers.

Dietary practices after primary treatment for ovarian cancer: A qualitative analysis from the OPAL Study

BACKGROUND

Little is known about dietary practices of women who have completed primary treatment for ovarian cancer, many of whom will go on to experience cancer recurrence and have further treatment. Knowledge of dietary practices is needed to optimize care.

OBJECTIVE

To identify dietary practices after primary treatment for ovarian cancer and evaluate how these practices differ by disease recurrence and treatment status.

DESIGN

Women with invasive epithelial ovarian cancer were provided with an open-ended question after completing a food frequency questionnaire (FFQ): "Is there anything we haven't asked you about your diet in the last 1-2 months that you feel is important?"

PARTICIPANTS/SETTING

Participants in the Ovarian cancer Prognosis And Lifestyle (OPAL) Study in Australia.

MAIN OUTCOMES

Dietary practices after primary treatment for ovarian cancer and factors affecting these practices.

ANALYSIS

Participants' responses were analyzed using content analysis. Individual content codes were categorized and reported by recurrence and treatment status at questionnaire completion.

RESULTS

286 women provided responses on 363 questionnaires. Those undergoing further treatment for recurrence commonly reported dietary regimens with clinical indications (e.g., low fiber to avoid bowel obstructions, high energy/protein to minimize nutritional deficits). Those not undergoing further treatment frequently reported 'popular' diets (e.g., organic, plant-based, alkaline). For women with cancer recurrence, dietary practices were affected by poor appetite and treatment late effects. For women without recurrence, other comorbidities, geographical location, family and friends appeared to influence dietary practices. In both groups, nutrition information sources and personal beliefs informed dietary practices. Participant responses that referenced media or online sources often included misinformation.

CONCLUSIONS

Following primary treatment for ovarian cancer, women report dietary practices that may not be captured in standard FFQs. Dietary practices and factors affecting these practices likely differ by treatment and recurrence status. Improved access to evidence-based dietary information and support is needed.

Reproductive Factors Do Not Influence Survival with Ovarian Cancer

BACKGROUND

Previous studies on the association between reproductive factors and ovarian cancer survival are equivocal, possibly due to small sample sizes.

METHODS

Using data on 11,175 people diagnosed with primary invasive epithelial ovarian, fallopian tube, or primary peritoneal cancer (ovarian cancer) from 16 studies in the Ovarian Cancer Association Consortium (OCAC), we examined the associations between survival and age at menarche, combined oral contraceptive use, parity, breastfeeding, age at last pregnancy, and menopausal status using Cox proportional hazard models. The models were adjusted for age at diagnosis, race/ethnicity, education level, and OCAC study and stratified on stage and histotype.

RESULTS

During the mean follow-up of 6.34 years (SD = 4.80), 6,418 patients passed away (57.4%). There was no evidence of associations between the reproductive factors and survival among patients with ovarian cancer overall or by histotype.

CONCLUSIONS

This study found no association between reproductive factors and survival after an ovarian cancer diagnosis.

IMPACT

Reproductive factors are well-established risk factors for ovarian cancer, but they are not associated with survival after a diagnosis of ovarian cancer.