Re-administration of platinum-based chemotherapy for recurrent endometrial cancer: an ancillary analysis of the SGSG-012/GOTIC-004/Intergroup study

BACKGROUND

We previously demonstrated the applicability of the concept of "platinum sensitivity" in recurrent endometrial cancer. Although immune checkpoint inhibitors have been widely incorporated into endometrial cancer treatment, the debate continues regarding treatment options in patients with recurrent endometrial cancer who have previously received platinum-based chemotherapy. In this study, we assessed the duration of response to secondary platinum-based treatment using pooled data from the SGSG-012/GOTIC-004/Intergroup study.

METHODS

Among the 279 participants in the SGSG-012/GOTIC-004/Intergroup study wherein platinum-based chemotherapy was re-administered for managing recurrent endometrial cancer between January 2005 and December 2009, 130 (47%) responded to chemotherapy. We compared the relationship between platinum-free interval and duration of secondary platinum-based treatment using pooled data.

RESULTS

In 40 patients (31%), the duration of response to secondary platinum-based treatment exceeded the platinum-free interval. The duration of response to secondary platinum-based treatment exceeded 12 months in 51 patients (39%) [platinum-free interval: < 12 months, 14/48 (29%); 12-23 months, 18/43 (42%); 24-35 months, 8/19 (42%); ≥ 36 months, 11/20 (55%)]. In particular, in eight patients (6%), the duration of response to secondary platinum-based treatment exceeded 36 months [platinum-free interval: < 12 months, 3/48 (6%); 12-23 months, 0/19 (0%); 24-35 months, 2/19 (11%); ≥ 36 months, 3/20 (15%)].

CONCLUSIONS

Re-administration of platinum-based chemotherapy for recurrent endometrial cancer may result in a long-term response exceeding the platinum-free interval in some patients. Even in the current situation, where immune checkpoint inhibitors have been introduced, re-administration of platinum-based chemotherapy is worth considering.

Treatment strategies for pelvic organ prolapse and postoperative outcomes in older women with long-term care needs: A population-based retrospective cohort study

OBJECTIVE

The study aimed to investigate treatment options for older women with pelvic organ prolapse (POP) and postoperative outcomes based on their long-term care (LTC) status.

METHODS

We used the medical and LTC insurance claims databases of Tochigi Prefecture in Japan, covering 2014 to 2019. We included women 65 years and older with POP and evaluated their care status and treatment, excluding women with an observation period <6 months. Among women with a postsurgical interval ≥6 months, we compared care level changes and deaths within 6 months and complications within 1 month postoperatively between those with and without LTC using Fisher exact test.

RESULTS

We identified 3406 eligible women. Of the 447 women with LTC and 2959 women without LTC, 16 (3.6%) and 415 (14.0%), respectively, underwent surgery. Among 393 women with a postsurgical interval ≥6 months, 19 (4.8%) required LTC at surgery. Two of the 19 women with LTC (10.5%) and eight of 374 women without LTC (2.1%) experienced worsening care-needs level. No deaths were recorded. Urinary tract infection (UTI) was significantly more frequent in women with LTC than in women without LTC (36.8% vs 8.6%). Other complications were rare in both groups.

CONCLUSION

The proportion of patients who underwent surgery for POP was lower in women with LTC than in women without LTC. Postoperative UTI was common and 11% had a worsening care-needs level postoperatively, whereas other complications were infrequent. Further detailed studies would contribute to providing optimal treatment to enhance patients' quality of life.

Increase in creatinine levels associated with niraparib maintenance therapy in ovarian cancer

AIM

In Japan, Niraparib maintenance therapy for primary and recurrent ovarian cancer was approved in September 2020 and is expected to improve the prognosis of ovarian cancer. However, the safety of niraparib maintenance therapy in Japanese patients has not been fully evaluated.

METHODS

Patients with ovarian cancer (including fallopian tube and peritoneal cancer) treated with niraparib at Jichi Medical University Hospital from September 2020 to August 2022 were enrolled in this study. Patient background, starting dose, rates of interruption, reduction, or discontinuation, adverse events (AEs) during treatment, and estimated glomerular filtration rate (eGFR) trends were retrospectively analyzed.

RESULTS

Twenty-nine patients received niraparib maintenance therapy during the study period, including 21 with primary cancer and 8 patients with recurrent cancer. Seventeen patients (58.6%) required dose interruptions and 16 patients (55.2%) required dose reductions. Only two patients (6.9%) discontinued treatment due to fatigue and nausea. The most frequent AE was creatinine increases in 18 patients (62.1%, all grades). Although eGFR levels decreased significantly after niraparib therapy compared to before niraparib therapy (59.3 vs. 50.3 mL/min/1.73 m2 , p < 0.001), the levels returned to pre-niraparib initiation levels after discontinuation of niraparib (64.6 vs. 64.6 mL/min/1.73 m2 , p = 0.96). Multivariate regression analysis showed that diabetes was independently associated with decreased eGFR (p = 0.013).

CONCLUSIONS

Niraparib maintenance therapy frequently increased serum creatinine, but the change was reversible. Further studies are needed to determine the effects of niraparib on renal function in Japanese patients.

Is the use of gonad protection protectors necessary during infants chest radiography?

INTRODUCTION AND OBJECTIVES

To compare gonad doses with and without a gonad protector and to optimize the use of gonadal protectors in infants thorax radiography.

MATERIALS AND METHODS

Two pediatric anthropomorphic phantoms are used: an X-ray system for KXO-50SS/DRX-3724HD, and a digital radiography system for CALNEO Smart C12, with and without a gonad protector during infants thorax radiography. A real time skin dosimeter is placed on the X-ray system, and a real time skin dosimeter is inserted on the front side of the mammary gland, the front and back sides of the true pelvis level, and on the ovaries and testes. The X-ray system is irradiated 15 times using phantoms with and without a gonad protector. The measured entrance patient doses values of for the real time skin dosimeter are compared for each phantom, with and without the gonad protector.

RESULTS

The medium of measured entrance patient doses values for front side dose of the true pelvis level with and without the protector are 10.00 and 5.00 μGy at newborn, and 10.00 and 0.00μGy at one year, respectively. The medium of measured entrance patient doses values for the back side dose of the true pelvis level with and without the protector are 0.00 and 0.00 μGy at both newborn one year, respectively. The measured entrance patient doses cannot be detected in the ovaries and testes with or without the protector. No significant differences are observed in the measured entrance patient doses values for the front and back side doses of the pelvis, ovaries, and testes at newborn and one year, with and without the protector (p>0.05).

CONCLUSIONS

No significant difference was observed in gonad dose measurements with and without the gonad protector during infants chest radiography. We believe that gonadal protector wearing is not necessary.

The role of non-genomic actions of progesterone and its membrane receptor agonist in ovarian cancer cell death

BACKGROUND

Progesterone therapy is a relatively inexpensive treatment option for endometrial and breast cancers, with few side effects. Two signaling pathways usually mediate the physiological effects of progesterone, namely genomic and non-genomic actions. Genomic action occurs slowly via the nuclear progesterone receptor (PR), whereas the membrane progesterone receptor (mPR) induces rapid non-genomic action.

AIMS

We investigated the effects of progesterone and various PR agonists on ovarian cancer cells.

METHODS AND RESULTS

PR expression of six serous ovarian cancer cell lines was examined by western blotting, and mPR expression was examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). PR-negative and mPR-positive ovarian cancer cells were exposed to progesterone and seven types of PR agonists (medroxyprogesterone acetate [MPA], dehydroepiandrosterone, dienogest, levonorgestrel, drospirenone, pregnenolone, and allopregnanolone) at 10-400 μM, and viable cell counts after exposure for 30 min were measured using the water-soluble tetrazolium (WST-1) assay. Ovarian cancer cell lines were exposed to 100 μM progesterone, and the expression of BAX, a pro-apoptotic protein, after 1-5 min was examined by western blotting. Western blotting detected no PR expression in the six serous ovarian cancer cell lines. In contrast, RT-qPCR detected mPR expression in all six serous ovarian cancer cell lines. Progesterone and MPA-induced cell death in all tested ovarian cancer cell lines in a concentration-dependent manner, whereas no effect was observed for other PR agonists. Western blotting revealed that pro-apoptotic protein BAX expression occurred 1 min after exposure to progesterone, suggesting that the cytocidal effects are mediated by rapid non-genomic action.

CONCLUSION

Progesterone and MPA exhibited a rapid cytocidal effect on PR-negative ovarian cancer cells through non-genomic action. Progesterone and MPA could be novel adjuvant therapies for ovarian cancer.

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.

Ovarian vein thrombosis after bilateral adnexectomy in a symptomatic patient with concomitant pulmonary embolism: A case report

OBJECTIVE

Ovarian vein thrombosis (OVT) after adnexectomy is usually asymptomatic, and pulmonary embolism (PE) has not been reported following this type of OVT. We present the case of a patient with symptomatic OVT after bilateral adnexectomy who experienced PE.

CASE REPORT

A 52-year-old woman underwent total laparoscopic hysterectomy and bilateral adnexectomy for early stage endometrial cancer. On the 12th postoperative day, she presented with a fever of 38.7 °C. Computed tomography (CT) revealed bilateral OVT. Anticoagulant and antibacterial therapy was initiated; after five days, the fever subsided. On the 19th postoperative day, CT revealed a decrement in OVT; however, PE was observed. By the 60th postoperative day, PE disappeared. No deep vein thromboses were detected at any time.

CONCLUSION

This case highlights that OVT, even after adnexectomy, can cause symptoms and PE can occur after this type of OVT. Anticoagulation therapy may be considered in such cases.

Neoadjuvant chemotherapy followed by interval debulking surgery for advanced epithelial ovarian cancer: GOTIC-019 study

INTRODUCTION

Three randomized controlled trials have resulted in extremely extensive application of the strategy of using neoadjuvant chemotherapy (NAC) followed by interval debulking surgery (IDS) for patients with advanced epithelial ovarian cancer in Japan. This study aimed to evaluate the status and effectiveness of treatment strategies using NAC followed by IDS in Japanese clinical practice.

PATIENTS AND METHODS

We conducted a multi-institutional observational study of 940 women with Federation of Gynecology and Obstetrics (FIGO) stages III-IV epithelial ovarian cancer treated at one of nine centers between 2010 and 2015. Progression-free survival (PFS) and overall survival (OS) were compared between 486 propensity-score matched participants who underwent NAC followed by IDS and primary debulking surgery (PDS) followed by adjuvant chemotherapy.

RESULTS

Patients with FIGO stage IIIC receiving NAC had a shorter OS (median OS: 48.1 vs. 68.2 months, hazard ratio [HR]: 1.34; 95% confidence interval [CI] 0.99-1.82, p = 0.06) but not PFS (median PFS: 19.7 vs. 19.4 months, HR: 1.02; 95% CI: 0.80-1.31, p = 0.88). However, patients with FIGO stage IV receiving NAC and PDS had comparable PFS (median PFS: 16.6 vs. 14.7 months, HR: 1.07 95% CI: 0.74-1.53, p = 0.73) and OS (median PFS: 45.2 vs. 35.7 months, HR: 0.98; 95% CI: 0.65-1.47, p = 0.93).

CONCLUSIONS

NAC followed by IDS did not improve survival. In patients with FIGO stage IIIC, NAC may be associated with a shorter OS.

Characteristics of submucosal leiomyomas that could cause severe hemorrhage with relugolix: an observational study

BACKGROUND

Relugolix, an oral gonadotrophin-releasing hormone receptor antagonist, was launched in Japan in 2019. Although there have been several studies on relugolix for leiomyomas, few have focused on submucosal leiomyomas. Submucosal leiomyomas cause bleeding more frequently than leiomyomas in other locations. There is only one case report described a patient treated for a submucosal leiomyoma with relugolix who developed severe hemorrhage. However, it remains unclear which characteristics of submucosal leiomyomas can lead to severe hemorrhage. Thus, the aim of this study was to investigate the characteristics of submucosal leiomyomas that would cause severe hemorrhage when treated with relugolix.

METHODS

We retrospectively reviewed records of patients who underwent treatment for submucosal leiomyoma with relugolix (40 mg once daily for up to 6 months) in our institute between December 2019 and September 2021. We evaluated the clinical course and characteristics of submucosal leiomyoma in patients who developed severe hemorrhage.

RESULTS

A total of 17 patients were treated for submucosal leiomyoma with relugolix. Two patients developed severe hemorrhage and required emergent surgery and blood transfusions. Only those two of the 17 patients had a submucosal leiomyoma of the International Federation of Gynecology and Obstetrics (FIGO) type 0, which has a stalk. In the remaining 15 patients who had FIGO type 1 or 2 leiomyoma, hemorrhage did not occur.

CONCLUSIONS

Our study suggests that the use of relugolix for FIGO type 0 leiomyomas may be associated with a risk of hemorrhage. However, relugolix may be a safe and effective treatment option for patients with FIGO type 1 or 2 leiomyomas.

Poor Treatment Outcomes of Locally Advanced Cervical Adenocarcinoma of Human Papilloma Virus Independent Type, Represented by Gastric Type Adenocarcinoma: A Multi-Center Retrospective Study (Sankai Gynecology Study Group)

The revised World Health Organization classification of cervical cancer divides adenocarcinomas into human papillomavirus-associated (HPVa) and -independent (HPVi) types; the HPVi type is represented by the gastric type. The treatment outcomes of locally advanced adenocarcinoma (LaAC), based on this classification, are understudied. We investigated the outcomes of patients with HPVa and HPVi LaACs. Data for all consecutive patients with stage IB3 to IIIC1 adenocarcinoma who received treatment at 12 institutions throughout Japan between 2004 and 2009 were retrieved to analyze progression-free and overall survival. Central pathological review classified 103 and 48 patients as having HPVa and HPVi tumors, respectively. Usual- (84%) and gastric- (90%) type adenocarcinomas were the most frequent subtypes. Surgery was the primary treatment strategy for most patients. Progression-free and overall survival of patients with HPVi were worse than those of patients with HPVa (p = 0.009 and 0.032, respectively). Subgroup analysis by stage showed that progression-free survival was significantly different for stage IIB. The current surgical treatment strategy for LaACs is less effective for HPVi tumors than for HPVa tumors, especially those in stage IIB.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Activated neutrophils inhibit chemotactic migration of activated T lymphocytes to CXCL11 by multiple mechanisms

Accumulation of T lymphocytes and neutrophils shows inversed association with the prognosis of cancer patients, suggesting infiltration of neutrophils and T cells might be differently regulated in tumor tissue. In this study, we stimulated neutrophils with PMA or LPS to produce neutrophil extracellular traps (NETs) and examined the effects on chemotactic migration of activated T cells to a representative T cell chemokine, CXCL11. Migration of the activated T cells was totally abrogated by PMA-stimulated neutrophils placed either in upper or lower chamber, which was mostly canceled by pretreatment with Catalase. Although LPS-stimulated neutrophils also inhibited T cell migration, depletion of NETs by ultracentrifugation or degradation of NETs with DNAse I restored T cell migration. Western blots showed that LPS-stimulated neutrophils thoroughly degraded CXCL11 with NETs dependent manner. Activated neutrophils inhibit T cell chemotaxis via multiple mechanisms including the release of H₂O₂ and chemokine degradation by NETs, which may suppress adaptive immunity.

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.

Abstract 6309: Activated neutrophils inhibit chemotactic migration of activated T lymphocytes to CXCL11 by multiple mechanisms

Objective High density of tumor-infiltrating lymphocytes (TILs) in the tumor is associated with favorable prognosis of cancer patients, while that of tumor-associated neutrophils (TAN) shows inverse correlation with outcome. We examined the effects of activated neutrophils on chemotactic migration of activated T cells in vitro. Methods Neutrophils and mononuclear cells (PBMC) were collected from the blood of healthy donor. Neutrophils were stimulated with PMA (1uM) or LPS (10ug/ml) for 15 min, washed extensively, and incubated for another 4 hours. PBMC were cultured on anti-CD3 mAb-coated plate with recomnibant-IL-2 (10ng/ml) for 7-14days. The activated T cells were placed in culture inserts with 3μm pore and migration to CXCL-11 (1000ng/ml) placed in lower chamber with or without neutrophils was examined after 2 hours. Random migration of activated T cells on fibronectin coated plate was evaluated with timelapsed analysis using Biostudio system. Degradation of CXCL-11 was examined with western blotting. Results Neutrophils stimulated with PMA or LPS produced neutrophil extracellular traps (NETs). Migration of T cells to CXCL-11 was drastically inhibited in the presence of PMA-activated neutrophils. The inhibition was similarly detected when NETs was removed from PMA-activated neutrophils by ultracentrifugation. Timelapse analysis also showed the NET-depleted supernatant greatly inhibited random migration, which was totally canceled by the pretreatment with 800U/ml catalase. When neutrophils were activated by LPS, T cell migration was also significantly inhibited (p=0.02) but not by NET-depleted supernatant (p=0.99). In western blotting, CXCL11 was totally degraded by LPS-stimulated neutrophils, which was greatly reduced by the depletion of NET component. CXCL11 degraded by NETs was restored by protease inhibitor, 5mM phenylmethylsulfonyl fluoride (PMSF). The reduced migration induced by LPS-stimulated neutrophils was mostly restored with 2mM PMSF. Conclusion Activated neutrophils inhibit chemotactic migration of activated T cells through multiple mechanisms including ROS production and chemokine degradation. TAN may have suppressive effects on the accumulation of TILs.

Citation Format: Kohei Tamura, Yuki Kaneko, Yurie Futoh, Kazuya Takahashi, Yuki Kimura, Akira Saito, Mineyuki Tojo, Hideyo Miyato, Hideyuki Ohzawa, Yasushi Saga, Yuji Takei, Hiroyuki Fujiwara, Joji Kitayama. Activated neutrophils inhibit chemotactic migration of activated T lymphocytes to CXCL11 by multiple mechanisms [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 6309.

Neutrophil extracellular traps (NETs) reduce the diffusion of doxorubicin which may attenuate its ability to induce apoptosis of ovarian cancer cells

Purpose

Although neutrophil extracellular traps (NETs) are present in various tumors, their roles in tumor biology have not been clarified yet. In this study, we examined how NETs affect the pharmacokinetics and effects of doxorubicin (DOX).

Methods

NETs were generated by neutrophils stimulated with phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). DOX was added to NETs and their distribution was observed under fluorescein microscopy, and the diffusion of DOX through 3 μM pores from lower to upper chambers was evaluated with a fluorescence-based assay. Ovarian cancer cells, KOC-2S and SKOV3, were embedded in collagen gel droplets and cultured in 3D way and their apoptosis was examined with flow cytometry.

Results

DOX was mostly co-localized with NETs. The transfer of DOX to upper chambers increased over time, which was significantly decreased by the presence of neutrophils stimulated with PMA or LPS in the lower chamber. DOX outside of the gel increased the rates of annexin V (+) apoptotic cells, which were significantly reduced by the addition of LPS-stimulated neutrophils in media both in KOC-2S and SKOV3. The reduced diffusion and apoptosis were mostly restored by the destruction of the NETs structure with 1000 u/ml DNAse I.

Conclusion

NETs efficiently trap and inhibit the diffusion of DOX which may attenuate its ability to induce apoptosis of ovarian cancer cells. Degradation of NETs with DNAse I may augment the response of ovarian cancer to DOX.

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Doxorubicin is efficiently trapped by neutrophil extracellular traps (NETs).

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NETs suppress diffusion of doxorubicin through micro-pores and infiltration into resected tumor.

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NETs suppress doxorubicin-induced apoptosis of tumor cells in 3-D culture.

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DNAse may augment the effect of anti-cancer drugs by modulating pharmacokinetics.

Durable response after the discontinuation of pembrolizumab treatment due to an adverse event in a patient with advanced endometrial cancer: A case report

The persistence of antitumor effects has been reported after the completion of treatment with immune checkpoint inhibitors (ICIs) for various types of carcinoma, such as malignant melanoma, exhibiting a durable response. A durable response has also been noted after the discontinuation of treatment at an early stage due to adverse events, including in renal pelvic cancer, pancreatic cancer and intrahepatic cholangiocarcinoma; however, to the best of our knowledge, a similar case report has not yet been published in the malignant gynecological tumor field. The present study described a patient with refractory advanced endometrial cancer in whom the administration of pembrolizumab was discontinued after the completion of the 7th course due to renal dysfunction; however, persistent tumor-reducing effects and decreases in the levels of tumor markers were noted for more than 18 months after the cessation of treatment. Pembrolizumab may be continuously administered to some patients for a long period, whereas a durable response is achieved by others even after its discontinuation at an early stage; therefore, difficulties are associated with selecting an appropriate duration of administration. Further studies are required to search for biomarkers that facilitate high-accuracy effect predictions, and to establish an optimal administration period in consideration of specific adverse reactions to ICIs and cost-effectiveness.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

The ACE trial: A randomized phase II study for advanced endometrial carcinoma

This study evaluated the feasibility and efficacy of three postoperative adjuvant chemotherapy regimens for endometrial cancer. Endometrioid cancer patients with intermediate-risk stage I and II or high-risk stage III and IV disease were randomly assigned to receive six cycles of either Paclitaxel-Epirubicin-Carboplatin (TEC), Paclitaxel-Anthracycline (Doxorubicin)-Carboplatin (TAC), or dose-dense paclitaxel-carboplatin (ddTC). The primary endpoint was the completion rate (CRate) of six cycles of treatment. The secondary endpoints were progression-free survival (PFS) and overall survival (OS). One hundred and one patients were treated as follows: 33 received TEC, 33 TAC, and 35 ddTC. The CRates for TEC, TAC and ddTC were 94%, 64% and 69%, respectively (p=0.005). The TEC CRate was significantly higher than for the other two groups. However, the PFS and OS outcomes were not statistically different between the three groups. The two-year survival rates were 94%, 97%, and 97% for TEC, TAC, and ddTC, respectively. When compared to the current standard treatments for endometrial cancer, TEC is a promising candidate for a phase III trial based on its significantly superior CRate and equivalent PFS and OS. This study is registered with UMIN Clinical Trials Registry (UMIN000008911).

HPV vaccine effectiveness by age at first vaccination among Japanese women

In Japan, the National Immunization Program against human papillomavirus (HPV) targets girls aged 12‐16 years, and catch‐up vaccination is recommended for young women up to age 26 years. Because HPV infection rates increase soon after sexual debut, we evaluated HPV vaccine effectiveness by age at first vaccination. Along with vaccination history, HPV genotyping results from 5795 women younger than 40 years diagnosed with cervical intraepithelial neoplasia grade 2‐3 (CIN2‐3), adenocarcinoma in situ (AIS), or invasive cervical cancer were analyzed. The attribution of vaccine‐targeted types HPV16 or HPV18 to CIN2‐3/AIS was 47.0% for unvaccinated women (n = 4297), but 0.0%, 13.0%, 35.7%, and 39.6% for women vaccinated at ages 12‐15 years (n = 36), 16‐18 years (n = 23), 19–22 years (n = 14), and older than 22 years (n = 91), respectively, indicating the greater effectiveness of HPV vaccination among those initiating vaccination at age 18 years or younger (P < .001). This finding was supported by age at first sexual intercourse; among women with CIN2‐3/AIS, only 9.2% were sexually active by age 14 years, but the percentage quickly increased to 47.2% by age 16 and 77.1% by age 18. Additionally, the HPV16/18 prevalence in CIN2‐3/AIS was 0.0%, 12.5%, and 40.0% for women vaccinated before (n = 16), within 3 years (n = 8), and more than 3 years after (n = 15) first intercourse, respectively (P = .004). In conclusion, our data appear to support routine HPV vaccination for girls aged 12‐14 years and catch‐up vaccination for adolescents aged 18 years and younger in Japan.