Ovarian cancer incidence and survival by histologic type in Osaka, Japan

Oncological outcomes among young women with non-epithelial ovarian cancer: the YOC-Care study (Young Ovarian Cancer - Care)

OBJECTIVE

To determine oncological outcomes and associated prognostic factors in women younger than 45 years diagnosed with non-epithelial ovarian cancer.

METHODS

A retrospective, multicenter Spanish study was performed including women with non-epithelial ovarian cancer younger than 45 years between January 2010 and December 2019. All types of treatments and stages at diagnosis with at least 12 months of follow-up were collected. Women with missing data, epithelial cancers, borderline or Krukenberg tumors, and benign histology, as well as patients with previous or concomitant cancer, were excluded.

RESULTS

A total of 150 patients were included in this study. The mean±SD age was 31.45±7.45 years. Histology subtypes were divided into germ cell (n=104, 69.3%), sex-cord (n=41, 27.3%), and other stromal tumors (n=5, 3.3%). Median follow-up time was 58.6 (range: 31.10-81.91) months. Nineteen (12.6%) patients presented with recurrent disease with a median time to recurrence of 19 (range: 6-76) months. Progression-free survival and overall survival did not significantly differ among histology subtypes (p=0.09 and 0.26, respectively) and International Federation of Gynecology and Obstetrics (FIGO) stage (I-II vs III-IV) with p=0.08 and p=0.67, respectively. Univariate analysis identified sex-cord histology with the lowest progression-free survival. Multivariate analysis showed that body mass index (BMI) (HR=1.01; 95% CI 1.00 to 1.01) and sex-cord histology (HR=3.6; 95% CI 1.17 to 10.9) remained important independent prognostic factors for progression-free survival. Independent prognostic factors for overall survival were BMI (HR=1.01; 95% CI 1.00 to 1.01) and residual disease (HR=7.16; 95% CI 1.39 to 36.97).

CONCLUSIONS

Our study showed that BMI, residual disease, and sex-cord histology were prognostic factors associated with worse oncological outcomes in women younger than 45 years diagnosed with non-epithelial ovarian cancers. Even though the identification of prognostic factors is relevant to identify high-risk patients and guide adjuvant treatment, larger studies with international collaboration are essential to clarify oncological risk factors in this rare disease.

Incidence and Survival Rates for Female Malignant Germ Cell Tumors: An Institutional Review

Background

Germ cell tumor survival rates have improved over the past few decades. However, there is a lack of data on survival rates and the incidence of female germ cell tumors. This study aims to determine the incidence and survival rates of female germ cell tumors in our institution.

Methodology

This retrospective cross-sectional study was carried out at Shaukat Khanum Memorial Hospital and Research Centre, and the records over 10 years, from January 2010 to December 2020 were examined. The data of 290 females with malignant germ cell tumors were selected from 1387 females with ovarian masses, and their survival records were examined. For statistical analysis, SPSS software (version 24.0; IBM Corp. Armonk, NY) was utilized. The survival analysis was determined using the Kaplan-Meier method.

Results

The mean age of patients was 21.45 ± 9.28 years. The mean duration of diagnosis was 4.53 ± 2.59 years. In 245 (84.5%) patients, ovarian malignancy was involved while uterine malignancy was observed in 44 (15.2%) cases and there was one (0.3%) case of cervical carcinoma. The most common stage at diagnosis of malignancy was IA (96 (33.1%)), followed by IIIC (58 (20.0%)), IV (56 (19.3%)) and IC (26 (9.0%)). Chemotherapy was given in 244 (84.1%) cases. Out of 290 cases, 26 (9.0%) had a recurrence of the tumor while 264 (91.0%) did not have a recurrence of the tumor. Out of 290 cases, 46 (15.9%) died during follow-up, 129 (44.4%) had disease-free survival while 115 (39.7%) were healthy till the end of the study. The mean duration of survival was 3.56 ± 2.33 years. When patients' survival was compared between treatment groups, patients who did not receive chemotherapy fared better than those who did.

Conclusion

Female germ cell tumor patients have a good overall survival rate of more than 20% after 10 years of follow-up with effective adjuvant therapy and conservative surgery. However, more research is needed to determine the long-term effects of chemotherapy on ovarian function.

Incidence and outcomes of malignant ovarian germ cell tumors in Korea, 1999-2017

OBJECTIVE

Malignant ovarian germ cell tumor (MOGCT) is a rare ovarian malignancy accounting for less than 5% of all ovarian cancers. We aimed to evaluate the incidence, survival, and subsequent malignancies after the diagnosis of MOGCT.

METHODS

Data from the Korea Central Cancer Registry were used to identify MOGCTs between 1999 and 2017. The age-standardized rates (ASRs), 5-year relative survival rates (RSR) and standardized incidence ratio (SIR) for subsequent cancer after diagnosis of MOGCT were estimated.

RESULTS

Of 2125 cases of newly diagnosed MOGCTs, 596 (28.0%) were diagnosed with dysgerminoma and 1529 (72.0%) with non-dysgerminoma. The ASR per 100,000 women-years was 0.539; ASR slightly increased over the study period (annual percent change [APC] = 1.01%; p = 0.02). There was an increase and decrease in the incidence of MOGCTs in the age groups 0-19 years (APC = 1.96%; p < 0.01) and ≥ 50 years (APC = -6.51%; p < 0.01), respectively. Patients with dysgerminoma showed significantly higher RSR than patients with non-dysgerminoma (98.0% vs. 94.9%, p < 0.01). Patients aged ≥50 years showed worst 5-year RSR (68.7%) than patients aged 0-19 years (97.8%) and 20-34 years (96.4%) (p < 0.01). The overall SIR for a subsequent cancer occurrence was 2.07, with the most frequent site of subsequent primary cancer being the thyroid (SIR = 2.78).

CONCLUSIONS

Our data demonstrated an excellent prognosis of MOGCTs among Korean women. There was a slight increase in MOGCT prevalence, which was more pronounced among those aged <19 years. After MOGCT diagnosis, the risk of developing a subsequent malignancy was doubled compared with the general population.

Non-epithelial ovarian cancer in Denmark - Incidence and survival over nearly 40 years

OBJECTIVE

To examine trends in incidence and survival of non-epithelial ovarian cancer in Denmark over nearly 40 years, using nationwide, population-based cancer registry data.

METHODS

From 1978 to 2016, we identified the non-epithelial ovarian cancer cases among all ovarian malignancies in the Danish Cancer Registry. Age-specific incidence rates, age-standardized incidence rates, and average annual percentage change (AAPC) were estimated with 95% confidence intervals (CIs). Overall and 5-year relative survival analyses were conducted and supplemented with Cox regression to explore the effect of different characteristics on overall mortality.

RESULTS

A total of 720 non-epithelial ovarian cancers were identified, corresponding to 3.4% of all ovarian malignancies. The majority of non-epithelial ovarian cancers were germ cell tumors (49.9%) and sex cord-stromal tumors (38.6%). The age-standardized incidence rate of germ cell tumors was stable over the study period, ranging between 0.33 and 0.39 per 100,000 woman-years. In contrast, the age-standardized incidence rate of sex cord-stromal tumors declined from 0.30 (1978-1987) to 0.09 (2008-2016) per 100,000 woman-years (AAPC = -5.15%; 95% CI: -7.29, -2.96). The 5-year relative survival of germ cell tumors and sex cord-stromal tumors was 94% and 79%, respectively, in the most recent period (2008-2011). Cox regression showed that overall mortality was associated with calendar year, age, and stage.

CONCLUSIONS

The incidence of germ cell tumors was stable over calendar time, whereas the incidence of sex cord-stromal tumors decreased significantly. Non-epithelial ovarian cancer overall mortality has decreased during the study period and this could not be explained by taking stage and age at diagnosis into account.

Global incidence comparisons and trends in ovarian germ cell tumors by geographic region in girls, adolescents and young women: 1988-2012

OBJECTIVE

Ovarian germ cell tumors (OGCT) are the primary ovarian malignancy affecting girls and young women. Globally, incidence rates and trends for OGCTs have not been compared in the literature and their etiology is not well described. Comparisons of incidence globally could inform etiologic hypotheses. The aim of this analysis was to evaluate geographic variation in OGCT incidence and to identify trends in incidence rates.

METHODS

Data were extracted from Cancer Incidence in 5 Continents (CI5) from 1988 to 2012. Rates of OGCT in women and girls were calculated for ages 0-9, 10-19, and 20-39 years and standardized to the 2000-2025 average world population. Data were aggregated within subregions corresponding to the United Nations Statistics Division (UNSD) geoscheme. Incidence rates were compared in subregions and average annual percent change (AAPC) was estimated using Poisson regression.

RESULTS

Overall, the highest incidence rates were observed in 10-19-year-olds. Incidence was generally the highest in Eastern Asia, Central America and North America. While incidence was variable by geographic region, less variation was observed in 0-9-year-olds as compared to adolescents and young adults. Significant increases in incidence were seen in some regions (Eastern Asia, Oceania, Western Europe, Southern Europe, and North America) and in countries with a high or very high human development index for one or more age groups.

CONCLUSIONS

Evaluating 25 years of OGCT incidence data, the highest incidence rates and largest increases in incidence were seen in Eastern Asia. Future studies should focus on etiologic features that may account for geographic variation and increases in incidence of OGCT.

Trends in incidence and survival outcome of epithelial ovarian cancer: 30-year national population-based registry in Taiwan

Objective

To investigate the changes of incidence and prognosis of epithelial ovarian cancer in thirty years in Taiwan.

Methods

The databases of women with epithelial ovarian cancer during the period from 1979 to 2008 were retrieved from the National Cancer Registration System of Taiwan. The incidence and prognosis of these patients were analyzed.

Results

Totally 9,491 patients were included in the study. The age-adjusted incidences of epithelial ovarian cancer were 1.01, 1.37, 2.37, 3.24, 4.18, and 6.33 per 100,000 person-years, respectively, in every 5-year period from 1979 to 2008. The age-specific incidence rates increased especially in serous, endometrioid and clear cell carcinoma, and the age of diagnosis decreased from sixty to fifty years old in the three decades. Patients with mucinous, endometrioid, or clear cell carcinoma had better long-term survival than patients with serous carcinoma (log rank test, p<0.001). Patients with undifferentiated carcinoma or carcinosarcoma had poorer survival than those with serous carcinoma (log rank test, p<0.001). The mortality risk of age at diagnosis of 30-39 was significantly higher than that of age of 70 years or more (test for trend, p<0.001). The mortality risk decreased from the period of 1996-1999 (hazard ratio [HR], 0.90; p=0.054) to the period after 2000 (HR, 0.74; p<0.001) as compared with that from the period of 1991-1995.

Conclusion

An increasing incidence and decreasing age of diagnosis in epithelial ovarian cancer patients were noted. Histological type, age of diagnosis, and treatment period were important prognostic factors for epithelial ovarian carcinoma.

Ovarian cancer mortality among women aged 40-79 years in relation to reproductive factors and body mass index: latest evidence from the Japan Collaborative Cohort study

Objective

This study mainly aimed to investigate the association of ovarian cancer mortality with reproductive factors and body mass index among Japanese women aged 40-79 years.

Methods

The source of the data was the Japan Collaborative Cohort (JACC) study which covered the period of 1988 to 2009. A representative sample of 64,185 women was used. Cox model was used to estimate the relative risk (RR) and 95% confidence interval (CI).

Results

The total number of ovarian cancer deaths was 98, with a mortality rate of 9.30 per 100,000 person-years. Women with single marital status revealed significantly higher age-adjusted RR (RR, 4.11; 95% CI, 1.66 to 10.23; p=0.005) as compared to married women. The effect of single marital status was stronger among older women aged 50+ years (RR, 4.58; 95% CI, 1.65 to 12.72; p=0.003) than younger women. An elevated risk was found for both nulliparous and nullipregnant women. Similarly, an increased risk of ovarian cancer mortality was estimated among overweight among aged 50 years or less.

Conclusion

Out of many factors only single marital status indicated a higher risk for ovarian cancer mortality. All other factors provided inconclusive results, which imply further epidemiological investigations.

Leptin stimulates ovarian cancer cell growth and inhibits apoptosis by increasing cyclin D1 and Mcl-1 expression via the activation of the MEK/ERK1/2 and PI3K/Akt signaling pathways

Obesity is known to be an important risk factor for many types of cancer, such as breast, prostate, liver and endometrial cancer. Recently, epidemiological studies have indicated that obesity correlates with an increased risk of developing ovarian cancer, the most lethal gynecological cancer in developed countries. Leptin is predominantly produced by adipocytes and acts as a growth factor and serum leptin levels positively correlate with the amount of body fat. In this study, we investigated the effects of leptin on the growth of ovarian cancer cells and the underlying mechanism(s) of action. Our results showed that leptin stimulated the growth of the OVCAR-3 ovarian cancer cell line using MTT assay and trypan blue exclusion. Using western blot analysis, we found that leptin enhanced the expression of cyclin D1 and Mcl-1, which are important regulators of cell proliferation and the inhibition of apoptosis. To investigate the signaling pathways that mediate the effects of leptin, cells were treated with leptin plus specific inhibitors of JAK2, PI3K/Akt and MEK/ERK1/2 and analysis of the phosphorylation state of proteins was carried out by western blot assays. We showed that the activation of the MEK/ERK1/2 and PI3K/Akt signaling pathways were involved in the growth-stimulating effect of leptin on ovarian cancer cell growth and the specific inhibitors of PI3K/Akt and MEK/ERK1/2 revealed that these two pathways interacted with each other. Our data demonstrate that leptin upregulates the expression of cyclin D1 and Mcl-1 to stimulate cell growth by activating the PI3K/Akt and MEK/ERK1/2 pathways in ovarian cancer.

Histology-specific long-term trends in the incidence of ovarian cancer and borderline tumor in Japanese females: a population-based study from 1983 to 2007 in Niigata

AIM

The histology-specific long-term trends in the incidence of ovarian cancer and borderline tumors in Japanese women were examined, based on data from the population-based cancer registry in Niigata, Japan.

MATERIAL AND METHODS

Data were obtained from the Niigata Gynecological Cancer Registry, which covered the entire female population in Niigata prefecture, Japan, during the period from 1983 to 2007.

RESULTS

A total of 3134 females with epithelial ovarian cancer, including borderline tumor cases, were diagnosed between 1983 and 2007. The age-standardized rates (ASRs) of both ovarian cancer and borderline tumors have steadily increased, with significant changes in ovarian cancer in all age groups, and borderline ovarian tumors in subjects aged <50. The ASRs of endometrioid adenocarcinoma showed a steady increasing trend, and those of clear cell and mucinous adenocarcinomas showed significant increasing trends in the total population. The ASRs of clear cell, mucinous, and endometrioid adenocarcinomas in the 50+ age group were significantly increased, especially the incidence of clear cell adenocarcinoma, which strikingly increased by approximately threefold from 1.2 (1983-1989) to 3.5 (2000-2007) per 100,000 females.

CONCLUSION

This prefecture-wide study showed the practical trends in ovarian cancer and borderline tumors in Japanese females. The incidence of ovarian cancer has steadily increased, with significant increases in the incidence of clear cell and mucinous adenocarcinomas in the total population during the past two decades. Because of the poor response rate of these histological subtypes to platinum-based regimens, novel treatment approaches should be adopted to improve the prognostic outcome in patients with ovarian cancer in Japan.

A retrospective analysis of clinicopathological and prognostic characteristics of ovarian tumors in the State of Espírito Santo, Brazil

BACKGROUND

Ovarian cancer is sixth most common cancer among women and the leading cause of death in women with gynecological malignancies. Despite the great impact ovarian cancer has on women's health and its great impact in public economy, Brazil still lacks valuable information concerning epidemiological aspects of this disease

METHODS

We've compiled clinical data of all ovarian tumors registered at the two public hospitals of reference (1997 - 2007), such as: patients' age at diagnosis, tumor histological type, tumor stage, chemotherapy regimens, chemotherapy responsiveness, disease-free survival, and overall survival.

RESULTS

Women's mean age at diagnosis was 54.67 ± 13.84 for ovarian cancer, 46.15 ± 11.15 for borderline tumors, and 42.01 ± 15.06 for adenomas. Among epithelial ovarian cancer cases, 30.1% were of serous, 13.7% were of mucinous, and 13.7% were of endometrioid type; exceptionally serous carcinoma was diagnosed in women younger than 30 years old. Endometrioid cancer had lower disease-free survival than others (p < 0.05). Cases were predominantly diagnosed as poor prognosis disease (FIGO III and IV, 56.2%). Regarding responsiveness to platinum-based therapy, 17.1% of patients were resistant, whereas 24.6%, susceptible. From these, we found equally responsiveness to platinum alone or its association with paclitaxel or cyclophosphamide.

DISCUSSION

Our data agreed with other studies regarding mean patients' age at diagnosis, histological type frequency, FIGO stages distribution, and chemotherapy regimens. However, the histological type distribution, with equal contribution of mucinous and endometrioid types seems to be a unique characteristic of the studied highly miscegenated population.

CONCLUSION

We have enlighten the profile of the studied ovarian cancer population, which might enable the development of more efficient political strategies to control this malignancy that is the fifth leading cause of cancer-related deaths among women.

Solid cancer incidence in atomic bomb survivors: 1958-1998

This is the second general report on radiation effects on the incidence of solid cancers (cancers other than malignancies of the blood or blood-forming organs) among members of the Life Span Study (LSS) cohort of Hiroshima and Nagasaki atomic bomb survivors. The analyses were based on 17,448 first primary cancers (including non-melanoma skin cancer) diagnosed from 1958 through 1998 among 105,427 cohort members with individual dose estimates who were alive and not known to have had cancer prior to 1958. Radiation-associated relative risks and excess rates were considered for all solid cancers as a group, for 19 specific cancer sites or groups of sites, and for five histology groups. Poisson regression methods were used to investigate the magnitude of the radiation-associated risks, the shape of the dose response, how these risks vary with gender, age at exposure, and attained age, and the evidence for inter-site variation in the levels and patterns of the excess risk. For all solid cancers as a group, it was estimated that about 850 (about 11%) of the cases among cohort members with colon doses in excess of 0.005 Gy were associated with atomic bomb radiation exposure. The data were consistent with a linear dose response over the 0- to 2-Gy range, while there was some flattening of the dose response at higher doses. Furthermore, there is a statistically significant dose response when analyses were limited to cohort members with doses of 0.15 Gy or less. The excess risks for all solid cancers as a group and many individual sites exhibit significant variation with gender, attained age, and age at exposure. It was estimated that, at age 70 after exposure at age 30, solid cancer rates increase by about 35% per Gy (90% CI 28%; 43%) for men and 58% per Gy (43%; 69%) for women. For all solid cancers as a group, the excess relative risk (ERR per Gy) decreases by about 17% per decade increase in age at exposure (90% CI 7%; 25%) after allowing for attained-age effects, while the ERR decreased in proportion to attained age to the power 1.65 (90% CI 2.1; 1.2) after allowing for age at exposure. Despite the decline in the ERR with attained age, excess absolute rates appeared to increase throughout the study period, providing further evidence that radiation-associated increases in cancer rates persist throughout life regardless of age at exposure. For all solid cancers as a group, women had somewhat higher excess absolute rates than men (F:M ratio 1.4; 90% CI 1.1; 1.8), but this difference disappears when the analysis was restricted to non-gender-specific cancers. Significant radiation-associated increases in risk were seen for most sites, including oral cavity, esophagus, stomach, colon, liver, lung, non-melanoma skin, breast, ovary, bladder, nervous system and thyroid. Although there was no indication of a statistically significant dose response for cancers of the pancreas, prostate and kidney, the excess relative risks for these sites were also consistent with that for all solid cancers as a group. Dose-response estimates for cancers of the rectum, gallbladder and uterus were not statistically significant, and there were suggestions that the risks for these sites may be lower than those for all solid cancers combined. However, there was emerging evidence from the present data that exposure as a child may increase risks of cancer of the body of the uterus. Elevated risks were seen for all of the five broadly classified histological groups considered, including squamous cell carcinoma, adenocarcinoma, other epithelial cancers, sarcomas and other non-epithelial cancers. Although the data were limited, there was a significant radiation-associated increase in the risk of cancer occurring in adolescence and young adulthood. In view of the persisting increase in solid cancer risks, the LSS should continue to provide important new information on radiation exposure and solid cancer risks for at least another 15 to 20 years.

PIEPOC: a new prognostic index for advanced epithelial ovarian cancer--Japan Multinational Trial Organization OC01-01

PURPOSE

The purpose of this study was to construct a simple and powerful prognostic index (PI) of epithelial ovarian cancer, the PIEPOC.

PATIENTS AND METHODS

In a retrospective review, data from 768 women with stage III or IV epithelial ovarian cancer from 24 institutions in Japan were evaluated for clinical features predictive of overall survival. A PI and risk groups to predict overall survival after initial surgery were developed using the proportional hazards regression model.

RESULTS

Of six factors, the four prognostic factors that remained independently significant in the analysis of a training sample (538 randomly selected patients) were age, performance status (PS), histologic cell type, and residual tumor size. From the regression function, we derived a PI = 1 (if age 70 and above) + 1 (if PS 1 or 2) + 2 (if PS 3 or 4) + 1 (if mucinous or clear-cell) + 2 (if residual size 0.1 cm and above). Patients were classified into three risk groups (PIEPOC): low risk (PI 0-2), intermediate risk (PI 3), and high risk (PI 4-6). The PIEPOC was equally predictive in a validation sample (n = 230), identifying three groups (5-year survival: 0.67 in low, 0.43 in intermediate, 0.17 in high risk).

CONCLUSION

Our proposed PI, the PIEPOC, was predictive in our patient population and may have utility in clinical practice. Prospective studies would be needed to confirm the prognostic predictive ability of the PIEPOC for patients with advanced epithelial ovarian cancer.

Sperm protein 17 influences the tissue-specific malignancy of clear cell adenocarcinoma in human epithelial ovarian cancer

Clear cell adenocarcinoma of the ovary has a poor prognosis due to chemoresistance and early metastasis to the lymph nodes. It also can result in endometriosis and is the second most frequent type of ovarian cancer in Japan. Serous adenocarcinoma of the ovary is another common epithelial cancer tissue subtype in Japan, and it is highly sensitive to chemotherapy. In the current study, we examined the differential expression of genes in these types of ovarian cancer and tried to analyze their functions, especially as they relate to chemoresistance. We used differential display to compare clear cell carcinoma and serous adenocarcinoma of the ovary. We identified sperm protein 17 (SP17) as a candidate gene related to the chemoresistance of clear cell carcinoma. Its differential expression was confirmed by real-time polymerase chain reaction. Because the function of the SP17 gene in ovarian cancer is not known, we examined the effect of small interfering RNA targeting the SP17 gene on the chemoresistance and proliferation of ES-2 ovarian cancer cells to paclitaxel, currently the most effective treatment for ovarian cancer. We found that this treatment decreased the chemoresistance of these cells to paclitaxel. Our results strongly suggest that SP17 plays a role in the resistance of clear cell carcinoma to chemotherapy without influencing their ability to proliferate

Proteomic search for potential diagnostic markers and therapeutic targets for ovarian clear cell adenocarcinoma

Clear cell adenocarcinoma (CCA) has a highly malignant potential in human epithelial ovarian cancer. The serum CA-125 is widely used as a marker for ovarian cancer, but the level is relatively low in CCA. Therefore, new sensitive biomarkers are required. In this report, we describe a promising proteomic analysis that is differentially expressed in CCA when compared to mucinous adenocarcinoma, using the ovarian cultured cell lines OVISE, OVTOKO, and MCAS. The disease-associated proteins were identified by 2-D differential gel electrophoresis (2-D DIGE) and MS. In this analysis, 18 up-regulated and 31 down-regulated spots were observed that had at least two-fold differences in the two CCA cell lines than in MCAS as control cells. Some of the proteins differentially expressed in CCA were previously observed as alternative expression levels in ovarian and/or other cancers in clinical samples. In a subsequent preliminary differential study using surgical specimens from patients with CCA, it was demonstrated that the identified proteins were expressed differentially in actual tissues, as well as in the CCA culture cells. The results from this investigation show the potentiality of a proteomic approach for identifying disease-associated proteins, which may eventually serve as diagnostic markers or therapeutic targets in CCA.

Incidence and survival rates for female malignant germ cell tumors

OBJECTIVE

To evaluate 30-year, population-based trends in incidence and survival rates for malignant germ cell tumors originating within the female genital tract.

METHODS

Surveillance, Epidemiology, and End Results data were used to identify malignant germ cell tumors (1973-2002). Overall and 5-year incidence rates, estimated annual percentage change, and survival rates were calculated and compared by age at diagnosis, race, stage, and histology.

RESULTS

Of 1,262 cases, there were 414 (32.8%) dysgerminomas, 449 (35.6%) immature teratomas, 37 (2.9%) mature teratomas with malignant degeneration, and 362 (28.7%) mixed germ cell tumors. The 30-year, age-adjusted incidence rate per 100,000 women-years was 0.338, decreasing by 29.4% for dysgerminomas (P = .18) and by 31.5% for mixed germ cell tumors (P = .22). Other nonwhites had higher rates than whites and blacks, but dysgerminoma rates were higher in whites and other nonwhites than in blacks. Using the registries for expanded races, rates were higher for Asian/Pacific Islanders (P = .059) and Hispanics (P = .07). By age at diagnosis, 15-19 year olds had the highest rates and the only significant change in rates (37.5% increase, P = .008). The 5-year relative survival was 83.9%. Survival rates improved significantly over calendar time and varied by histologic subtype, race, stage of disease, and age at diagnosis.

CONCLUSION

Over the past 30 years, germ cell tumor incidence rates have declined in women and differ from rising trends reported for testicular tumors. Survival rates have improved but were lower for older women and for nondysgerminoma subtypes.

A pathology study of malignant and benign ovarian tumors among atomic-bomb survivors--case series report

The present article describes the series of incident primary ovarian tumors in the Life Span Study (LSS) cohort of the Radiation Effects Research Foundation, with particular emphasis on case ascertainment and characterization of histological features of the tumors. We identified 723 ovarian tumors (260 malignant, 463 benign) in 648 individuals of about 70,000 female LSS subjects; 71 cases had more than one ovarian tumor. We histologically confirmed 601 tumors (182 malignant, 419 benign tumors). The most frequent histological type was common epithelial tumor (90.7% for malignant and 59.7% for benign tumors). The distributions of ovarian tumors by histological type were similar to those from other studies. Among malignancies, the frequency of common epithelial types relative to other tumor types increased with radiation dose (p = 0.02). Among benign tumors, the relative frequency of sex-cord stromal tumors increased with radiation dose (p = 0.04). The women with mucinous cancer had better survival than those with serous cancers (p = 0.03). Within tumor types, there was no consistent pattern of survival by radiation dose. Variations in histological types of ovarian tumors in response to radiation dose, suggested by the case series data need to be followed up by population-based incidence analysis.

A decreasing incidence of ovarian carcinoma in Israel

The aim of the present study was to assess the incidence trend of invasive epithelial ovarian carcinoma in Israel. We assessed the incidence rate of invasive epithelial ovarian cancer in Israeli Jewish women during the 10-year period from 1993 to 2002 based on data obtained from the population-based Israel National Cancer Registry. There was a gradual significant decrease in the incidence of ovarian cancer from 9.64 in 1993 to 6.55 in 2002. The decrease in incidence was evident in all ethnic groups except those born in Asia and in all the age groups older than 35 years. The decrease in incidence of ovarian carcinoma is gratifying, but its reason remains obscure.

Does hormone replacement therapy prevent epithelial ovarian cancer?

Two much-debated hypotheses regarding the aetiology of epithelial ovarian cancer (EOC) are incessant ovulation and gonadotrophin stimulation. A significant inverse correlation is found between the risk of EOC and number of pregnancies, duration of oral contraceptive use (about 10% risk reduction per year) and duration of breastfeeding. Whereas ovulation in the 20-29 year age group was associated with a 20% increase in risk for each year of ovulation, maximum protective effect was noticed in late childbirth (>35 years). Although both in-vitro and in-vivo studies showed that gonadotrophins may initiate and stimulate the growth of EOC, it is not known whether gonadotrophins promote EOC. FSH and LH receptors have been detected by ligand-binding assay and by reverse transcriptase polymerase chain reaction in ovarian surface epithelium (OSE) and in malignant epithelial ovarian tissue. Key aetiological events for this cancer may occur in the premenopausal period. Although hormone replacement therapy (HRT) can lower FSH and LH concentrations substantially, it cannot reduce EOC. The ideal time of ovulation and/or gonadotrophin suppression for prevention of EOC, and why oral contraceptives (OC) can but HRT cannot reduce EOC effectively, are unknown. Various growth-related genes, factors, adhesion molecules and angiogenic factors are present in OSE. Pituitary ovarian axis hormones seem to maintain a delicate balance towards growth control whilst the resultant chain of abnormal growth-promoting events occur at cellular level. Reports regarding the relation of exogenous and endogenous hormones, especially oestrogen, and post-menopausal EOC are reviewed.

Relationship between body mass index and the risk of ovarian cancer in the Japanese population: Findings from the Japanese Collaborate Cohort (JACC) study

AIM

The incidence of ovarian cancer in Japan has increased since the 1970s. The many studies that have assessed the relationship between body mass index (BMI) and the risk of ovarian cancer have produced contradictory results. Here we investigated this relation using data from the Japan Collaborative Cohort Study for the Evaluation of Cancer Risk, which was initiated in 1988.

METHODS

A self-administered questionnaire on dietary habits and other risk factors for cancer was completed by 36,456 Japanese women. After 7.6 years of follow up, 38 cases of ovarian cancer were available for analysis. Cox proportional-hazards models were used to compute relative risks and to adjust for confounders.

RESULTS

Compared to women with BMI of 18.5-24.9 kg/m2, the relative risk of ovarian cancer was 2.24 (95% CI = 1.10-4.21) for BMI of 25.0-29.9 and 1.78 (95% CI = 0.24-13.34) for BMI of > or = 30 kg/m2. A test for trend revealed that this finding was statistically significant (P = 0.014).

CONCLUSION

The results of this study suggest that being overweight is independently associated with a higher risk of developing ovarian cancer in the Japanese population.

Cigarette smoking and the risk of ovarian cancer in the Japanese population: Findings from the Japanese Collaborate Cohort study

AIM

The many studies into the relation between cigarette smoking and the risk of ovarian cancer have produced inconsistent results. Here we investigated this relation using data from the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, initiated in 1988.

METHODS

A self-administered questionnaire on smoking habits and other risk factors for cancer was completed by 34 639 Japanese women. After 7.6 years of follow up, 39 cases of ovarian cancer were available for analyses. Cox proportional-hazards models were used to compute relative risks (RR) and to adjust for confounders.

RESULTS

Relative to those who had never smoked, the RR of ovarian cancer were 1.63 (95% confidence interval [CI] = 0.21-12.50) for former smokers and 2.27 (95% CI = 0.85-6.08) for current smokers. Among current smokers, the RR were 1.48 (95% CI = 0.20-10.92), 5.56 (95% CI = 1.68-19.06), and 1.86 (95% CI = 0.25-14.30) among women who smoked <10, 10-19, and at least 20 pack-years ([number of cigarettes smoked per day/20] x number of years subject has smoked), respectively, relative to those who had never smoked. A test for trend was statistically significant (P = 0.044).

CONCLUSIONS

These data indicate that cigarette smoking increases the risk of developing ovarian cancer in the Japanese population.

[Evolution of therapeutic practices and survival of ovarian cancer in Bourgandi between 1982-1996: a registry-based study]

OBJECTIVE

The aim of this study is to describe the evolution of therapeutic practices and the evolution of survival between 1982 and 1996 in a population of ovarian carcinomas. All the patients were registered in the "Registre des Cancers Gynécologiques de Côte-d'Or-France".

POPULATION AND METHODS

During this period, 546 cases of ovarian cancers were registered. Data about FIGO staging at the diagnosis, histologic type, initial surgical procedures and survival were studied.

RESULTS

During this period, 61.7% of the patients had a complete resection of their tumor. The frequency of complete removal increased significantly during the period of this study. Complete removal moved from 56%, between 1982 and 1984, up to 75%, between 1993 and 1996. Complete removal was possible in 98.1% of the FIGO stage 1 cases while it was possible in only 18.3% of the stage IV. 76.9% of the patients younger than 50 years old had a complete removal while only 29% of the women older than 80 years old had a complete removal. Fifty percent of stage I received chemotherapy as long as 85% of patients younger than 50 years old. After 1993, only 2.6% of them had radiotherapy. The global survival rate at 5 years was 35.4%.

CONCLUSIONS

Surgery is the major procedure to obtain a complete remission of ovarian cancer. The efficacy of current chemotherapies may modify the initial management of these tumors, particularly in modifying the chronology of the different therapeutic sequences.

Influence of hospital procedure volume on ovarian cancer survival in Japan, a country with low incidence of ovarian cancer

The survival of ovarian cancer patients has been reported to be superior at hospitals with a high volume of operations. A population-based study was carried out to assess whether this is true in Japan, where the incidence rate is relatively low as compared with other developed countries. The Osaka Cancer Registry's data were used to investigate associations between hospital procedure volume and survival of ovarian cancer patients. Hospitals were ranked according to the number of operations for ovarian cancer performed per year (high/medium/low/very low). Survival analysis was restricted to the reported 2450 cases who lived in Osaka Prefecture (except for Osaka City) diagnosed in 1975-1995, or those who resided in Osaka City in 1993-1995, since active follow-up data on vital status 5 years after the diagnosis were available. The relative 5-year survival for all ovarian cancer cases was 38.8%, and the survival was higher with greater hospital volume (22.3% / 34.2% / 46.2% / 55.0%). After adjustment for age, histologic type and cancer stage by the Cox regression model, patients receiving care in very-low-volume hospitals were seen to have a 60% higher risk of death than patients receiving care in high-volume hospitals (P < 0.01). Although some limitations existed in this study, the results indicated that further centralization of operative treatment in high-volume hospitals might improve survival of ovarian cancer patients in Japan.