Human papillomavirus vaccine impact on invasive cervical cancer in Japan: Preliminary results from cancer statistics and the MINT study.

The first prophylactic vaccine against human papillomavirus (HPV) 16 and HPV18 was licensed in Japan in 2009. HPV vaccine effectiveness against high-grade cervical lesions has been demonstrated among young Japanese women, but evidence of its effects on invasive cervical cancer (ICC) is lacking. Using data from two different cancer registries, we compared recent trends of new ICC cases by age group using Poisson regression analysis. We also analyzed time trends in HPV16/18 prevalence among 1414 Japanese women aged <40 years newly diagnosed with ICC in the past decade. Based on the population-based cancer registry, the incidence of ICC among young women aged 20-29 years showed a significant decline from 3.6 to 2.8 per 100 000 women-years during 2016-2019, but no similar decline was observed for older age groups (p < 0.01). Similarly, using data from the gynecological cancer registry of the Japan Society of Obstetrics and Gynecology, the annual number of ICCs among women aged 20-29 years also decreased from 256 cases to 135 cases during 2011-2020 (p < 0.0001). Furthermore, a declining trend in HPV16/18 prevalence in ICC was observed only among women aged 20-29 years during 2017-2022 (90.5%-64.7%, p = 0.05; Cochran-Armitage trend test). This is the first report to suggest population-level effects of HPV vaccination on ICC in Japan. Although the declining trend in HPV16/18 prevalence among young women with ICC supports a causal linkage between vaccination and results from cancer registries, further studies are warranted to confirm that our findings are attributable to vaccination.

Low-grade appendiceal mucinous neoplasm encountered during risk-reducing salpingo-oophorectomy: A case of laparoscopic surgery.

Low-grade appendiceal mucinous neoplasm (LAMN) is a rare epithelial malignancy of the appendix. If it perforates the abdominal cavity, it can cause a serious clinical syndrome called pseudomyxoma peritonei. In the present case, we laparoscopically removed a LAMN encountered during risk-reducing salpingo-oophorectomy (RRSO). The patient was a 53-year-old woman who was diagnosed with hereditary breast and ovarian cancer syndrome. RRSO was planned, and magnetic resonance imaging revealed a large cystic tumor in the right lower abdomen. We expected an ovarian cyst; however, it was a primary tumor of the appendix. Partial cecal resection was performed laparoscopically by a surgical oncologist. The pathological diagnosis was LAMN. Gynecologists may encounter this disease incidentally. Mucinous appendiceal neoplasm (MAN) may be encountered during RRSO. If a right lower abdominal mass is found near a normal ovary preoperatively, gynecologists should consider MAN as well as paraovarian cyst.

Impact of lower co-payments on risk-reducing salpingo-oophorectomy and BRCA testing in Japan.

BACKGROUND: In April 2020, insurance coverage for risk-reducing salpingo-oophorectomy (RRSO) for breast cancer patients with hereditary breast and ovarian cancer (HBOC) syndrome and BRCA testing were started in Japan. We investigated the impact of insurance coverage on the number of RRSO and BRCA tests performed. METHODS: The subjects were 370 breast cancer patients and 23 of their relatives who received genetic counseling at our institution between April 2014 and December 2021. Finally, 349 patients and 15 relatives were analyzed. We retrospectively compared the number of BRCA tests, RRSO, insurance status, and co-payment of medical expenses before and after insurance coverage based on medical records. RESULTS: In the 6-year pre-coverage period, 226 patients (mean: 37/year) received genetic counseling and 106 (17/year) received BRCA testing. In the 21-month post-coverage period, 161 patients (92/year) received genetic counseling and 127 (72/year) received BRCA testing. The rate of testing/counseling significantly increased in the post-coverage period (46.9% vs. 78.8%; p < .001). The number of patients who were diagnosed with HBOC were 24 (4/year) and 18 (10/year) and RRSO was performed for 7 (1/year) and 11 (6/year) patients in the pre- and post-coverage periods, respectively. The rate of RRSO/HBOC was significantly increased in the post-coverage period (29.1% vs. 61.1%; p = 0.039). RRSO patients' co-payment rates decreased from 64% to 25% pre- and post-coverage. CONCLUSIONS: Our findings suggest that decreased co-payments were the primary reason for these increases. Insurance coverage is an important factor when promoting preventive medical services such as RRSO.

Significance of positive peritoneal cytology for recurrence and survival in patients with endometrial cancer.

AIM: This study aims to examine the association between malignant peritoneal cytology and prognosis in women with endometrial cancer. METHODS: We retrospectively analyzed the records of patients with endometrial cancer who underwent surgery with intraoperative peritoneal cytology at our hospital between January 1988 and December 2012. All results were reclassified according to the 2009 International Federation of Gynecology and Obstetrics (FIGO) system, and the relation between intraoperative peritoneal cytology results and recurrence and prognosis was examined. RESULTS: Of the 908 patients analyzed, 205 (22.6%) had positive peritoneal cytology. Patients with positive peritoneal cytology had significantly lower rates of recurrence-free survival (RFS) and overall survival (OS) than those in the negative cytology group (both p < 0.001). Subgroup analysis of patients with FIGO stage I/II showed significantly lower RFS in the positive-cytology group (p = 0.005), but there was no significant difference in OS (p = 0.637). In the patients with FIGO stage III/IV or patients classified as "high risk," the RFS and OS were significantly lower in the positive-cytology group (both p < 0.001). Cox regression analysis identified positive peritoneal cytology as a significant predictor of recurrence in patients with FIGO stage I/II disease. CONCLUSIONS: Patients with positive peritoneal cytology for endometrial cancer have a high risk of recurrence, regardless of histopathologic type or FIGO stage. Peritoneal cytology has already been removed from the 2009 FIGO classification of endometrial cancer, but it may deserve reconsideration.

Regional differences in human papillomavirus type 52 prevalence among Japanese women with cervical intraepithelial neoplasia†.

Although geographical differences in the distribution of human papillomavirus genotypes have been observed worldwide, no studies have reported on national differences in the prevalence of human papillomavirus types in Japan. Here, we report a cross-sectional study to explore regional differences in the prevalence of human papillomavirus types among Japanese women with cervical intraepithelial neoplasia or invasive cervical cancer. Using human papillomavirus genotyping data from the nationwide prospective study on human papillomavirus vaccine effectiveness, we compared the frequency of detection of 15 high-risk and two low-risk human papillomavirus types in each disease category between the women who visited hospitals located in eastern Japan and those who visited hospitals located in western Japan. The risk of cervical intraepithelial neoplasia progression was assessed by calculating a prevalence ratio of each human papillomavirus type for cervical intraepithelial neoplasia grade 2/3 versus grade 1. Among the human papillomavirus types studied, human papillomavirus 52 was detected significantly more frequently in western hospitals than in eastern hospitals in cervical intraepithelial neoplasia grade 1 patients, but was less frequent in cervical intraepithelial neoplasia grade 2/3. The prevalence of particular human papillomavirus types was not significantly different between patients in hospitals in eastern Japan and those in hospitals in western Japan for invasive cervical cancer. In both eastern and western hospitals, a higher risk of cervical intraepithelial neoplasia progression was observed in patients infected with human papillomavirus 16, 31 or 58. In contrast, there was a significantly higher prevalence of human papillomavirus 52 infection in women with cervical intraepithelial neoplasia grade 2/3 than in those with cervical intraepithelial neoplasia grade 1 in eastern hospitals (prevalence ratio, 1.93; 95% confidence interval, 1.48-2.58), but not in western hospitals (prevalence ratio, 1.03; 95% confidence interval, 0.83-1.30). Regional differences of human papillomavirus 52 prevalence in cervical intraepithelial neoplasia lesions may exist and emphasize the importance of continuous monitoring of human papillomavirus type prevalence throughout the country in order to accurately assess the efficacy of human papillomavirus vaccines.

Changes in HPV16/18 Prevalence among Unvaccinated Women with Cervical Intraepithelial Neoplasia in Japan: Assessment of Herd Effects following the HPV Vaccination Program.

Since the human papillomavirus (HPV) vaccination program for Japanese girls aged 12-16 years began in 2010, vaccination uptake has been low in women born before 1993 but high (approximately 70%) in those born during 1994-1999. We previously compared the prevalence of vaccine types HPV16 and HPV18 in cervical intraepithelial neoplasia grade 1-3 (CIN1-3) or adenocarcinoma in situ (AIS) between vaccinated and unvaccinated cohorts and found direct protection effects among vaccinated women in Japan. In this study, we focused on changes in HPV16/18 prevalence among "unvaccinated" cohorts with CIN/AIS. We analyzed HPV16/18 prevalence among 5051 unvaccinated women aged <40 years, newly diagnosed with CIN/AIS during 2012-2021 for time trends. Declining trends in HPV16/18 prevalence over 9 years were observed in CIN1 (36.0-10.0%, Ptrend = 0.03) and CIN2-3/AIS (62.5-36.4%, Ptrend = 0.07) among women aged <25 years. HPV16/18 prevalence in CIN1 and CIN2-3/AIS diagnosed at age 20-24 years was lower in 1994-1999 birth cohorts compared with 1988-1993 birth cohorts (4.5% vs. 25.7% for CIN1 and 40.0% vs. 58.1% for CIN2-3/AIS, both p = 0.04). Significant reduction in HPV16/18 prevalence among young unvaccinated women with CIN1 and CIN2-3/AIS suggests herd effects of HPV vaccination in Japan.

Reduction in HPV16/18 prevalence among young women with high-grade cervical lesions following the Japanese HPV vaccination program.

The Japanese government began a human papillomavirus (HPV) vaccination program for girls aged 12-16 years in 2010 but withdrew its recommendation in 2013 because of potential adverse effects, leading to drastically reduced vaccination uptake. To evaluate population-level effects of HPV vaccination, women younger than 40 years of age newly diagnosed with cervical intraepithelial neoplasia grade 1-3 (CIN1-3), adenocarcinoma in situ (AIS), or invasive cervical cancer (ICC) have been registered at 21 participating institutes each year since 2012. A total of 7709 women were registered during 2012-2017, of which 5045 were HPV genotyped. Declining trends in prevalence of vaccine types HPV16 and HPV18 during a 6-year period were observed in CIN1 (50.0% to 0.0%, Ptrend  < .0001) and CIN2-3/AIS (83.3% to 45.0%, Ptrend  = .07) only among women younger than 25 years of age. Overall, HPV vaccination reduced the proportion of HPV16/18-attributable CIN2-3/AIS from 47.7% to 33.0% (P = .003): from 43.5% to 12.5% as routine vaccination (P = .08) and from 47.8% to 36.7% as catch-up vaccination (P = .04). The HPV16/18 prevalence in CIN2-3/AIS cases was significantly reduced among female individuals who received their first vaccination at age 20 years or younger (P = .02). We could not evaluate vaccination effects on ICC owing to low incidence of ICC among women aged less than 25 years. We found HPV vaccination to be effective in protecting against HPV16/18-positive CIN/AIS in Japan; however, our data did not support catch-up vaccination for women older than 20 years. Older adolescents who skipped routine vaccination due to the government's suspension of its vaccine recommendation could benefit from receiving catch-up vaccination before age 20 years.

Negative peritoneal washing cytology during interval debulking surgery predicts overall survival after neoadjuvant chemotherapy for ovarian cancer.

OBJECTIVE: Optimal debulking in interval debulking surgery (IDS) after neoadjuvant chemotherapy (NAC) has been reported as a prognostic factor for patients with ovarian cancer. However, the identification of microscopic residual disease (MRD) using visualization and palpation is subjective. Peritoneal washing cytology (PWC) during IDS is an easy-to-implement, objective approach for assessing disease status, although its clinical relevance and association with MRD is not known. The aim of this study was to evaluate the efficacy of PWC during IDS. METHODS: In total, 164 patients diagnosed with ovarian cancer at our institution were retrospectively evaluated, including 64 who had received NAC. Seventeen patients had undergone an exploratory laparotomy followed by NAC, while the remaining patients were diagnosed based on imaging, peritoneal cytology, and tumor markers. The PWC was performed before intraperitoneal observation at laparotomy during IDS. RESULTS: NAC-treated patients had stage III-IV disease. IDS was performed in 78.1% of NAC-treated patients. Seventeen patients (26.6%) were PWC-negative and 33 patients (51.6%) were PWC-positive. Fourteen patients (21.9%) had progressive disease and were ineligible for IDS. The median overall survival of the PWC-negative, PWC-positive, and non-IDS groups was 47, 18, and 5 months, respectively. The differences were significant (p<0.01). PWC was an independent prognostic factor in the multivariate Cox regression analysis (p<0.001). CONCLUSION: PWC during IDS may be a prognostic factor for NAC-treated patients with ovarian cancer. PWC may be more useful than visualization and palpation in IDS for determining the presence of MRD.

Serum CA 125 Level after Neoadjuvant Chemotherapy is Predictive of Prognosis and Debulking Surgery Outcomes in Advanced Epithelial Ovarian Cancer.

Recently, neoadjuvant chemotherapy followed by interval debulking surgery (NACT-IDS) has been recommended for selected patients with International Federation of Gynecology and Obstetrics (FIGO) stage III or IV disease and bulky tumors. The aim of this study was to evaluate associations between post-NACT serum CA 125 levels, surgical outcomes, and clinical outcomes in patients with advanced epithelial ovarian cancer. We retrospectively analyzed 107 patients with FIGO stage III or IV ovarian cancer who were treated with NACT-IDS at the Gynecology Department of Kanagawa Cancer Center between January 2001 and December 2012. Serum CA 125 levels after NACT were significantly lower in the complete/optimal IDS group compared to the suboptimal IDS group (mean±standard deviation: 48.1±27.6 vs. 346.5±295.2 U/mL, p<0.01). Patients with low preoperative CA 125 levels (<35 U/mL) had a higher probability of optimal IDS (78.1±41.9% vs. 33.3±19.2%, p<0.01) and longer progression-free survival (mean±standard deviation: 30.4±14.3 months vs. 21.3±7.3 months, p<0.05) than patients with high CA 125 levels (>100 U/mL). Patients with low CA 125 levels (<35 U/mL) had a higher probability of complete/optimal IDS and longer progression-free survival compared to patients with high CA 125 levels (>100 U/mL).

A preoperative risk-scoring system to predict lymph node metastasis in endometrial cancer and stratify patients for lymphadenectomy.

OBJECTIVE: This study aimed to validate the preoperative scoring system adopted in the Kanagawa Cancer Center (KCC) to stratify endometrial cancer patients for lymphadenectomy according to the risk of developing lymph node metastasis (LNM). METHODS: The records of 432 and 221 uterine cancer patients treated in the KCC and Yokohama City University (YCU), respectively, were retrospectively analyzed. The KCC classified patients for LNM risk based on tumor volume, myometrial invasion, histological grade, and serum CA125 levels, while YCU used only myometrial invasion. Lymphadenectomy was omitted for 156 patients with 0 LNM risk, while pelvic lymphadenectomy (PLX) or PLX with para-aortic lymphadenectomy (PLAX) were performed for those with low and high LNM risk, respectively. The predicted and actual LNM rates were compared between the KCC and YCU patients, and cancer recurrence and overall survival were analyzed. RESULTS: There was no difference in survival between patients with LNM score 0 who were or were not treated with lymphadenectomy. None (0%) developed LNM and only 1 (0.6%) had recurrence. Patients who underwent PLX but not PLAX (low LNM score) had a low tumor recurrence rate in the para-aortic nodes (1.3%). The KCC scoring system was significantly more accurate than the YCU system in predicting LNM in the high-risk group (P<0.05) and demonstrated that PLAX was unnecessary in almost 50% of the YCU cases. CONCLUSION: The KCC preoperative scoring system is useful to predict LNM risk, and thereby prevent unnecessary lymphadenectomy or to determine its extent in endometrial cancer patients.

Analysis of stage IVB endometrial carcinoma patients with distant metastasis: a review of prognoses in 55 patients.

BACKGROUND: Adequate treatment for extremely advanced endometrial cancer is unknown. The purpose of this study was to clarify the prognosis of patients with stage IVB endometrial carcinoma and the validity of treatment. Furthermore, we evaluated whether there was a connection between the prognosis and the site of metastasis. METHODS: The prognoses of 55 patients with stage IVB endometrial carcinoma were studied with reference to the initial treatment method and the metastatic site at the time of the initial treatment. RESULTS: The median survivals of the group of 35 patients who were initially treated with surgery and the group of 10 patients who underwent radiotherapy or chemotherapy as their initial treatment followed by surgery were 11.5 months and 9.5 months, respectively. The residual tumor diameter after surgery was precisely measured in 40 of these 45 patients. The prognosis was significantly better in the patients with a residual tumor diameter of less than 2 cm compared to those with a tumor diameter of 2 cm or greater, and the median survival periods in these two groups were 23.5 months and 11.5 months, respectively (P = 0.027). Furthermore, the prognosis of patients with lung metastasis was significantly better than that of patients with non-lung hematogenous metastasis; the median survival periods of these two groups were 18.5 months and 10.5 months, respectively (P = 0.014). CONCLUSION: For operable patients, surgery as an initial treatment and reduction of the residual tumor size to less than 2 cm appeared to contribute to a better prognosis. In addition, conservative initial treatment and the presence of non-lung hematogenous metastasis were poor prognostic factors.