Qualitative age interactions between low-grade and high-grade serous ovarian carcinomas

Early-Onset Ovarian Cancer <30 Years: What Do We Know about Its Genetic Predisposition?

Ovarian cancer (OC) is one of the leading causes of cancer-related deaths in women. Most patients are diagnosed with advanced epithelial OC in their late 60s, and early-onset adult OC diagnosed ≤30 years is rare, accounting for less than 5% of all OC cases. The most significant risk factor for OC development are germline pathogenic/likely pathogenic variants (GPVs) in OC predisposition genes (including BRCA1, BRCA2, BRIP1, RAD51C, RAD51D, Lynch syndrome genes, or BRIP1), which contribute to the development of over 20% of all OC cases. GPVs in BRCA1/BRCA2 are the most prevalent. The presence of a GPV directs tailored cancer risk-reducing strategies for OC patients and their relatives. Identification of OC patients with GPVs can also have therapeutic consequences. Despite the general assumption that early cancer onset indicates higher involvement of hereditary cancer predisposition, the presence of GPVs in early-onset OC is rare (<10% of patients), and their heritability is uncertain. This review summarizes the current knowledge on the genetic predisposition to early-onset OC, with a special focus on epithelial OC, and suggests other alternative genetic factors (digenic, oligogenic, polygenic heritability, genetic mosaicism, imprinting, etc.) that may influence the development of early-onset OC in adult women lacking GPVs in known OC predisposition genes.

A prognostic system for epithelial ovarian carcinomas using machine learning

Introduction

Integrating additional factors into the International Federation of Gynecology and Obstetrics (FIGO) staging system is needed for accurate patient classification and survival prediction. In this study, we tested machine learning as a novel tool for incorporating additional prognostic parameters into the conventional FIGO staging system for stratifying patients with epithelial ovarian carcinomas and evaluating their survival.

Material and methods

Cancer‐specific survival data for epithelial ovarian carcinomas were extracted from the Surveillance, Epidemiology, and End Results (SEER) program. Two datasets were constructed based upon the year of diagnosis. Dataset 1 (39 514 cases) was limited to primary tumor (T), regional lymph nodes (N) and distant metastasis (M). Dataset 2 (25 291 cases) included additional parameters of age at diagnosis (A) and histologic type and grade (H). The Ensemble Algorithm for Clustering Cancer Data (EACCD) was applied to generate prognostic groups with depiction in dendrograms. C‐indices provided dendrogram cutoffs and comparisons of prediction accuracy.

Results

Dataset 1 was stratified into nine epithelial ovarian carcinoma prognostic groups, contrasting with 10 groups from FIGO methodology. The EACCD grouping had a slightly higher accuracy in survival prediction than FIGO staging (C‐index = 0.7391 vs 0.7371, increase in C‐index = 0.0020, 95% confidence interval [CI] 0.0012–0.0027, p = 1.8 × 10⁻⁷). Nevertheless, there remained a strong inter‐system association between EACCD and FIGO (rank correlation = 0.9480, p = 6.1 × 10⁻¹⁵). Analysis of Dataset 2 demonstrated that A and H could be smoothly integrated with the T, N and M criteria. Survival data were stratified into nine prognostic groups with an even higher prediction accuracy (C‐index = 0.7605) than when using only T, N and M.

Conclusions

EACCD was successfully applied to integrate A and H with T, N and M for stratification and survival prediction of epithelial ovarian carcinoma patients. Additional factors could be advantageously incorporated to test the prognostic impact of emerging diagnostic or therapeutic advances.

Differential expression of miR-130a-3p modulate ovarian epithelial carcinoma (OEC) cell development and could be a biomarker for OEC

A lot of research investigations, conducted in the recent years, establishes that microRNAs (miRNAs) have an important role in keeping both growth and metastasis of Ovarian Epithelial Carcinoma (OEC) under control. However, the clinical and functional role of miR-130a-3p in OEC is yet to be explored. Through quantitative reaction i.e., qRT-PCR, the expression of miR-130a-3p was assessed in tissues and cell lines of OEC patients. This analysis determined the relationship between the expression of miR-130a-3p and its clinicopathology with the overall survival rate of OEC patients. The author made use of cell counting analysis (CCK8) and in vitro flow cytometry to understand the functional and biological impact of miR-130a-3p expression. In comparison with neighboring normal tissues, the expression of miR-130a-3p was found to be lower in 7 OEC samples. Few reasons are cited for this scenario i.e., low expression of miR-130a-3p, such as low overall OEC patient survival rate, incidence of FIGO and metastasis of lymph nodes. miR-130a-3p has been found as an independent candidate for predicting the prognosis of OEC patients, as per Multivariate Cox research. When miR-130a-3p is over-expressed, as per the enhanced mechanism, it prevents both cell proliferation and cell cycle production in OEC. The current study findings emphasize that miR-130a-3p can be leveraged as a biomarker of prognosis and possibly as a target in the treatment of OEC.

A Subset of Malignant Mesotheliomas in Young Adults Are Associated With Recurrent EWSR1/FUS-ATF1 Fusions

Malignant mesothelioma (MM) is a rare, aggressive tumor often associated with asbestos exposure and characterized by complex genetic abnormalities, including deletions of chromosome 22. A gene fusion involving EWSR1 and YY1 gene on 14q32 has been reported in 2 patients over the age of 60 with peritoneal MM. However, the incidence of EWSR1 rearrangements in MM and the spectrum of its fusion partners remain unknown. We recently encountered 2 MM cases with EWSR1-ATF1 fusions and sought to investigate the prevalence and clinicopathologic features associated with this abnormality. As both index cases occurred as intra-abdominal tumors in young adults, we searched our files for pleural and peritoneal MM occurring in adults younger than age of 40. All cases were tested by fluorescence in situ hybridization using custom bacterial artificial chromosomes probes for EWSR1, FUS, and ATF1 genes. When available, immunohistochemistry for BAP1 was performed. A total of 25 MM from patients aged 40 or less were screened, either from peritoneum (n=13) or pleura (n=12), with a median age of 31 (range: 7 to 40 y). Two additional ATF1-rearranged tumors were identified at pleural and peritoneal sites with EWSR1 and FUS as fusion partners, respectively, for a total of 4 cases (16%, 4/25). The fusion-positive cases displayed classic epithelioid morphology, immunoreactivity for cytokeratins and WT1, and negativity for S100. BAP1 expression was retained in the 3 fusion-positive cases with available material, and in 80% (12/15) of the fusion-negative cases. Our results expand the spectrum of tumor types harboring EWSR1/FUS-ATF1 gene fusions to include a subgroup of conventional epithelioid MM. Other features of this unique MM subset include young age at presentation, lack of asbestos exposure and retained BAP1 expression.

Relationships of Tubal Ligation to Endometrial Carcinoma Stage and Mortality in the NRG Oncology/ Gynecologic Oncology Group 210 Trial

BACKGROUND

Stage is a critical determinant of treatment among endometrial carcinoma patients; understanding patterns of tumor spread may suggest approaches to improve staging. Specifically, the importance of exfoliation of endometrial carcinoma cells through the fallopian tubes into the peritoneum is ill defined. We assessed the hypothesis that tubal ligation (TL), which should impede transtubal passage of cells, is associated with lower endometrial carcinoma stage at presentation and, consequently, lower mortality.

METHODS

The NRG Oncology/Gynecologic Oncology Group (GOG) 210 Trial included 4489 endometrial carcinoma patients who completed a risk factor questionnaire that included TL history. Pathology data were derived from clinical reports and central review. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between TL with stage and peritoneal metastasis, overall and by tumor subtype. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals for TL and mortality. All statistical tests were two-sided.

RESULTS

Compared with stage I, TL was inversely associated with stage III (OR = 0.63, 95% CI = 0.52 to 0.78) and stage IV carcinomas (OR = 0.14, 95% CI = 0.08 to 0.24) overall and among individual tumor subtypes. TL was inversely related to peritoneal metastasis overall (OR = 0.39, 95% CI = 0.22 to 0.68) and among serous carcinomas (OR = 0.28, 95% CI = 0.11 to 0.68). In multivariable models unadjusted for stage, TL was associated with lower endometrial carcinoma-specific mortality (HR = 0.74, 95% CI = 0.61 to 0.91); however, adjustment for stage eliminated the survival advantage. Similar relationships with all-cause mortality were observed.

CONCLUSIONS

TL is associated with lower stage and mortality among women with aggressive endometrial carcinomas, suggesting transtubal spread is clinically important. Future studies should evaluate whether detection of intraluminal tumor cells is prognostically relevant.

Medical history, lifestyle, family history, and occupational risk factors for sporadic Burkitt lymphoma/leukemia: the Interlymph Non-Hodgkin Lymphoma Subtypes Project

BACKGROUND

The etiologic role of medical history, lifestyle, family history, and occupational risk factors in sporadic Burkitt lymphoma (BL) is unknown, but epidemiologic and clinical evidence suggests that risk factors may vary by age.

METHODS

We investigated risk factors for sporadic BL in 295 cases compared with 21818 controls in a pooled analysis of 18 case-control studies in the International Lymphoma Epidemiology Consortium (InterLymph). Cases were defined to include typical BL or Burkitt-like lymphoma. Odds ratios (ORs) and 95% confidence intervals (CIs) for associations were calculated separately for younger (<50 years) and older (≥ 50 years) BL using multivariate logistic regression.

RESULTS

Cases included 133 younger BL and 159 older BL (age was missing for three cases) and they were evenly split between typical BL (n = 147) and Burkitt-like lymphoma (n = 148). BL in younger participants was inversely associated with a history of allergy (OR = 0.58; 95% CI = 0.32 to 1.05), and positively associated with a history of eczema among individuals without other atopic conditions (OR = 2.54; 95% CI = 1.20 to 5.40), taller height (OR = 2.17; 95% CI = 1.08 to 4.36), and employment as a cleaner (OR = 3.49; 95% CI = 1.13 to 10.7). BL in older participants was associated with a history of hepatitis C virus seropositivity (OR = 4.19; 95% CI = 1.05 to 16.6) based on three exposed cases. Regardless of age, BL was inversely associated with alcohol consumption and positively associated with height.

CONCLUSIONS

Our data suggest that BL in younger and older adults may be etiologically distinct.

A web tool for age-period-cohort analysis of cancer incidence and mortality rates

BACKGROUND

Age-period-cohort (APC) analysis can inform registry-based studies of cancer incidence and mortality, but concerns about statistical identifiability and interpretability, as well as the learning curves of statistical software packages, have limited its uptake.

METHODS

We implemented a panel of easy-to-interpret estimable APC functions and corresponding Wald tests in R code that can be accessed through a user-friendly Web tool.

RESULTS

Input data for the Web tool consist of age-specific numbers of events and person-years over time, in the form of a rate matrix of paired columns. Output functions include model-based estimators of cross-sectional and longitudinal age-specific rates, period and cohort rate ratios that incorporate the overall annual percentage change (net drift), and estimators of the age-specific annual percentage change (local drifts). The Web tool includes built-in examples for teaching and demonstration. User data can be input from a Microsoft Excel worksheet or by uploading a comma-separated-value file. Model outputs can be saved in a variety of formats, including R and Excel.

CONCLUSIONS

APC methodology can now be carried out through a freely available user-friendly Web tool. The tool can be accessed at http://analysistools.nci.nih.gov/apc/.

IMPACT

The Web tool can help cancer surveillance researchers make important discoveries about emerging cancer trends and patterns.

Agreement for tumor grade of ovarian carcinoma: analysis of archival tissues from the surveillance, epidemiology, and end results residual tissue repository

BACKGROUND

Emerging data suggest that ovarian cancers differ by tumor grade. However, the reliability of microscopic grade from paraffin tissue in the general medical community and as reflected in population-based cancer registries is unknown.

METHODS

We examined grade agreement between two gynecologic pathologists and the Surveillance Epidemiology and End Results Residual Tissue Repository (SEER). Grade agreement was assessed with percent observer agreement and kappa coefficients for 664 invasive ovarian carcinomas, using previously defined three-tier and two-tier grading systems. A random subset of ovarian carcinomas was selected to compare intra- and inter-pathologist agreement.

RESULTS

Five hundred and eighty-six of SEER's 664 tumors were confirmed invasive. Percent agreement was 49 % with fair kappa coefficient = 0.25 (95 % CI: 0.20-0.30) for the 664 tumors. Agreement improved slightly when restricted to the 586 confirmed invasive cancers; it was better for high grade than low grade tumors, for two-tier than three-tier grading systems, and within (66 %) than between study pathologists (43 %). Grade was not a robust independent predictor of ovarian cancer-specific survival.

CONCLUSIONS

Grade agreement was fair between SEER and study pathologists irrespective of grading system. Recorded grade in SEER should be used with caution and is probably not a reliable metric for ovarian cancer epidemiology.

Significant calendar period deviations in testicular germ cell tumors indicate that postnatal exposures are etiologically relevant

PURPOSE

The current working model of type II testicular germ cell tumor (TGCT) pathogenesis states that carcinoma in situ arises during embryogenesis, is a necessary precursor, and always progresses to cancer. An implicit condition of this model is that only in utero exposures affect the development of TGCT in later life. In an age-period-cohort analysis, this working model contends an absence of calendar period deviations. We tested this contention using data from the SEER registries of the United States.

METHODS

We assessed age-period-cohort models of TGCTs, seminomas, and nonseminomas for the period 1973-2008. Analyses were restricted to whites diagnosed at ages 15-74 years. We tested whether calendar period deviations were significant in TGCT incidence trends adjusted for age deviations and cohort effects.

RESULTS

This analysis included 32,250 TGCTs (18,475 seminomas and 13,775 nonseminomas). Seminoma incidence trends have increased with an average annual percentage change in log-linear rates (net drift) of 1.25 %, relative to just 0.14 % for nonseminoma. In more recent time periods, TGCT incidence trends have plateaued and then undergone a slight decrease. Calendar period deviations were highly statistically significant in models of TGCT (p = 1.24(-9)) and seminoma (p = 3.99(-14)), after adjustment for age deviations and cohort effects; results for nonseminoma (p = 0.02) indicated that the effects of calendar period were much more muted.

CONCLUSION

Calendar period deviations play a significant role in incidence trends of TGCT, which indicates that postnatal exposures are etiologically relevant.

Survival rates for international federation of gynecology and obstetrics stage III ovarian carcinoma by cell type: a study of 262 unselected patients with uniform pathologic review

OBJECTIVE

Published data are conflicting on the influence of cell type on prognosis in ovarian cancer. The recent separation of low-grade serous carcinoma as a distinctive cell type of ovarian cancer with an indolent behavior, in retrospect, suggests that survival in studies that have not separated this group may be inaccurate.

METHODS

An unselected series of 262 International Federation of Gynecology and Obstetrics stage III ovarian carcinomas was studied. Diagnostic classification of each tumor was made with particular attention to recent refinements in cell-type classification. Survival curves were constructed according to Kaplan-Meier and compared with the log-rank test.

RESULTS

The 5-year survival for 207 high-grade serous carcinomas was 40%, as compared with 71% for 18 patients with low-grade serous carcinoma (P = 0.0113). Low-grade serous carcinoma was significantly more likely to be optimally debulked (P = 0.0039) and significantly less likely to be substage IIIC (P < 0.0001). The survival for carcinosarcoma was significantly inferior to all serous carcinomas (P = 0.0322). The significance of this latter comparison was lost when carcinosarcomas were compared with only high-grade serous carcinoma (P > 0.05).

CONCLUSIONS

Low-grade serous carcinoma has a significantly better prognosis than high-grade serous carcinoma and also differs with regard to substage distribution and proportion of patients optimally debulked. Because of its excellent prognosis, failure to separate low-grade serous carcinomas, notwithstanding its infrequent occurrence, can change the results of survival analyses that do not make this separation.

Low-grade serous carcinomas of the ovary contain very few point mutations

It has been well established that ovarian low-grade and high-grade serous carcinomas are fundamentally different types of tumours. While the molecular genetic features of ovarian high-grade serous carcinomas are now well known, the pathogenesis of low-grade serous carcinomas, apart from the recognition of frequent somatic mutations involving KRAS and BRAF, is largely unknown. In order to comprehensively analyse somatic mutations in low-grade serous carcinomas, we applied exome sequencing to the DNA of eight samples of affinity-purified, low-grade, serous carcinomas. A remarkably small number of mutations were identified in seven of these tumours: a total of 70 somatic mutations in 64 genes. The eighth case displayed mixed serous and endometrioid features and a mutator phenotype with 783 somatic mutations, including a nonsense mutation in the mismatch repair gene, MSH2. We validated representative mutations in an additional nine low-grade serous carcinomas and 10 serous borderline tumours, the precursors of ovarian low-grade, serous carcinomas. Overall, the genes showing the most frequent mutations were BRAF and KRAS, occurring in 10 (38%) and 5 (19%) of 27 low-grade tumours, respectively. Except for a single case with a PIK3CA mutation, other mutations identified in the discovery set were not detected in the validation set of specimens. Our mutational analysis demonstrates that point mutations are much less common in low-grade serous tumours of the ovary than in other adult tumours, a finding with interesting scientific and clinical implications.

Age-period-cohort models in cancer surveillance research: ready for prime time?

Standard descriptive methods for the analysis of cancer surveillance data include canonical plots based on the lexis diagram, directly age-standardized rates (ASR), estimated annual percentage change (EAPC), and joinpoint regression. The age-period-cohort (APC) model has been used less often. Here, we argue that it merits much broader use. First, we describe close connections between estimable functions of the model parameters and standard quantities such as the ASR, EAPC, and joinpoints. Estimable functions have the added value of being fully adjusted for period and cohort effects, and generally more precise. Second, the APC model provides the descriptive epidemiologist with powerful new tools, including rigorous statistical methods for comparative analyses, and the ability to project the future burden of cancer. We illustrate these principles by using invasive female breast cancer incidence in the United States, but these concepts apply equally well to other cancer sites for incidence or mortality.

Trimodal age-specific incidence patterns for Burkitt lymphoma in the United States, 1973-2005

Burkitt lymphoma (BL) is a unique B-cell non-Hodgkin lymphoma with 3 established clinical-epidemiological variants: endemic, sporadic and AIDS-related BL. BL variants show characteristic dysregulation of MYC gene, but the causes of MYC dysregulation or BL arising at different ages are poorly understood. Therefore, we examined population-based BL incidence patterns in the United States to determine age-related risk. BL case and population data were obtained from the NCI's Surveillance, Epidemiology and End Results Databases (1973-2005). Standard cross-sectional age-standardized and age-specific incidence rates were stratified by sex and race and supplemented with age-period-cohort models. We analyzed 3,058 BL cases diagnosed during 1,160,300,297 person-years of observation. Age-standardized incidence rates rose 6.8% per year (95% CI 4.5-9.1) for males and 7.1% (95% CI 3.2-11.1) for females during the study period. The rate among males was 3.2 times that among females, and among Whites 1.3 times that among Blacks. Male-to-female incidence rate ratios did not differ by race, but were 4.2 for pediatric (0-19 years), 4.1 for adult (20-59 years) and 2.0 for geriatric (> or = 60 years) BL. Cross-sectional age-specific rates showed 2 separate peaks among males and females, near ages 10 and 75 years, and a 3rd peak near age 40 years among males. The tri/bimodal incidence pattern was present in sensitivity analyses excluding registries with many HIV/AIDS cases and in period-specific, cohort-specific analyses. To our knowledge, tri/bimodal incidence patterns have not previously been reported for BL. Trimodal/bimodal BL suggests heterogeneity in etiology or biology of BL diagnosed at different ages in males and females.