Mayumi Kobayashi-Kato

Questionnaire-based survey on the extent of lymph node dissection during interval debulking surgery after neoadjuvant chemotherapy for patients with advanced ovarian cancer in the Gynecologic Cancer Study Group of JCOG

The significance of lymph node dissection (LND) in primary debulking surgery (PDS) for advanced ovarian cancer was demonstrated in the LION trial. However, the role and the current practices of LND during interval debulking surgery (IDS) remains unclear. We aimed to conduct a survey of the current LND practices. A questionnaire-based survey regarding the criteria and extent of LND for advanced ovarian cancer was conducted by the Gynecologic Cancer Study Group of the Japan Clinical Oncology Group (JCOG). We defined enlarged lymph nodes as 10 mm or more in the short axis on imaging. This study included data from 51 institutions. Factors contributing to the decision regarding the extent of LND included performance status, completeness of cytoreductive surgery excluding the lymph nodes, and age. Regarding PDS cases with enlarged lymph nodes, 90% of all institutions opted for systematic LND (SyLND) or removal of only the enlarged lymph nodes (SeLND). In IDS cases with enlarged lymph nodes after neoadjuvant chemotherapy (NACT), 15 (29%) and 35 (69%) institutions opted for SyLND and SeLND, respectively. In contrast, in IDS cases in which enlarged lymph nodes were reduced after NACT, approximately half the institutions opted for no LND. This study found no established standard treatment for LND during IDS in patients with enlarged lymph nodes among the JCOG institutions. Thus, further prospective studies comparing the prognostic outcomes with or without LND are warranted.

Ovarian Mesonephric-like Adenocarcinoma: Its Prevalence in a Japanese High-Volume Cancer Center and a Literature Review on Therapeutic Targets

Background: Ovarian mesonephric-like adenocarcinoma (MLA) is a newly described histological type known for its aggressive behavior. This study aims to determine the frequency of ovarian MLA, review the existing literature, and elucidate its clinicopathological characteristics, including the potential therapeutic targets. Methods: We retrospectively reviewed the pathological diagnoses of 501 primary ovarian cancer surgical cases at our institution from 2010 to 2023. MLAs exhibiting typical morphological and immunohistochemical features were included. The frequency and clinicopathological characteristics of these cases were summarized. Additionally, we conducted a literature search using PubMed to collect and summarize previously reported cases of ovarian MLAs. Results: Among the 501 primary ovarian cancer cases, we identified 3 cases (0.6%) of MLA. The patients were 52–76 years old, and the initial FIGO stages were IC1 (two cases) and IIIB (one case). All the cases exhibited HRP, pMMR, PD-L1 negativity (CPS < 1), and low HER2 expression. Two cases experienced metastatic recurrence. A literature review identified 97 cases of MLA. The MLAs frequently exhibited KRAS mutations (90%, 38/42), with a recurrence rate of 39% (26/67). Conclusion: MLAs accounted for 0.6% of malignant ovarian tumors at our institution, all of which were advanced or recurrent cases. These cases showed HRP, pMMR, and PD-L1 negativity, indicating a lack of current therapeutic targets. The literature also reported a high incidence of advanced and recurrent cases, highlighting the need for accurate diagnosis and the development of new treatments. The frequent KRAS mutations suggest a potential therapeutic target for recurrent or metastatic MLA.

Novel classification of ovarian metastases originating from colorectal cancer by radiological imaging and macroscopic appearance

Diagnosis of secondary ovarian tumors originating from colorectal cancer has previously been based upon history of malignancy and radiological findings of bilateral masses with a "stained glass appearance." The purpose of this study was to perform a detailed investigation of the radiological and macroscopic features of ovarian metastases originating from colorectal cancer, which remain to be fully characterized. Study participants were 48 consecutive patients with ovarian metastases from colorectal cancer who underwent resection of ovarian tumors at the National Cancer Center Hospital between August 1998 and January 2019. Ovarian tumors were classified into subgroups using computed tomography (CT), magnetic resonance imaging (MRI), and macroscopic appearance. CT/MRI findings and macroscopic appearance were classified into the following four types: type 1 (oval, homogeneous-solid) (n = 5); type 2 (heterogeneous-solid, small in size with multinodular surface) (n = 3); type 3 (solid-cystic, predominantly solid) (n = 18); and type 4 (cystic-solid, multilocular with solid components) (n = 22). Type 1 mimics Krukenberg tumors, type 2 mimics ovarian metastases from breast cancer, type 3 mimics primary ovarian endometrioid cancer, and type 4 mimics primary ovarian mucinous cancer, with a "stained glass appearance". Twenty-eight (58%) patients had bilateral metastases. Eleven patients (23%) underwent hysterectomy and/or pelvic lymph node dissection in addition to ovarian resection. We introduced a novel classification system for ovarian metastases originating from colorectal cancer, which may be beneficial for assessing ovarian metastases from colorectal cancer and avoiding unnecessary surgery due to misdiagnosis of primary ovarian tumors.

TP53 gene and pathway alterations in gastric-type adenocarcinoma of the cervix

Abstract Background Human papillomavirus infection contributes to the development of almost all cervical malignancies, aside from gastric-type adenocarcinoma of the cervix, a rare aggressive subtype without human papillomavirus infection. Methods To address the carcinogenic mechanism of this disease, we performed a comparative multi-omics analysis of gastric-type adenocarcinoma of the cervix and usual-type endocervical adenocarcinoma in 3 independent cohorts of patients with gastric-type adenocarcinoma of the cervix and usual-type endocervical adenocarcinoma. The first cohort comprised 8 gastric-type adenocarcinoma of the cervix and 22 patients with usual-type endocervical adenocarcinoma treated at the National Cancer Center Hospital between 2002 and 2020, who were examined by targeted and whole transcriptome sequencing. The other 2 cohorts comprised 52 patients with gastric-type adenocarcinoma of the cervix and 109 patients with usual-type endocervical adenocarcinoma and 39 patients with gastric-type adenocarcinoma of the cervix and 232 patients with usual-type endocervical adenocarcinoma, whose mutational data were obtained from the Center for Cancer Genomics and Advanced Therapeutics (Japanese patients) and Genomics Evidence Neoplasia Information Exchange (US patients) public databases, respectively. Metabolomic analysis was performed in 8 patients, including 5 with gastric-type adenocarcinoma of the cervix. Results TP53 mutations were more prevalent in gastric-type adenocarcinoma of the cervix than in usual-type endocervical adenocarcinoma in all 3 cohorts. Transcriptome analysis consistently revealed frequent suppression of TP53-related pathways in gastric-type adenocarcinoma of the cervix. Metabolites preferentially detected in gastric-type adenocarcinoma of the cervix tissues suggest TP53 alterations are implicated in intratumoral metabolic properties. Conclusion The development of gastric-type adenocarcinoma of the cervix is likely driven by TP53 mutations, which play a large role in shaping intracellular signaling and metabolic profiles within tumor cells.

Prevalence and outcomes of germline pathogenic variants of homologous recombination repair genes in ovarian cancer

AbstractGermline pathogenic variants (PVs) are pivotal in gynecological oncology. We focused on the prevalence, clinicopathological features, and survival impact of homologous recombination repair (HRR) PVs in patients with epithelial ovarian cancer (EOC). This was a multicenter retrospective cohort study, and 1248 patients with EOC were registered. Eligible patients (n = 1112) underwent germline DNA analysis for 26 cancer predisposition genes, including nine HRR‐related genes, such as BRCA1/2, BRIP1, PALB2, RAD51C/D, and ATM. The associations between clinicopathological factors and HRR‐related PVs were examined. Kaplan–Meier and Cox regression analyses were conducted. Among 1091 analyzed patients, 153 (14.0%) carried PVs and 140 (12.8%) were HRR‐related. HRR‐PV‐positive status significantly correlated with serous carcinoma (22.9% vs. 4.8%, P < 0.0001) and advanced disease (18.5% vs. 5.9%, P < 0.0001). The HRR‐PV‐positive group exhibited higher prevalence of personal breast (12.9%) and familial breast/ovarian (29.2%) cancer history. HRR status independently improved overall survival in stage III/IV disease (P = 0.04) but not progression‐free survival. HRR‐related germline PVs exhibit distinct clinicopathological features with survival implications. Variants were significantly associated with serous carcinoma and advanced disease, underscoring the importance of genetic testing to develop individualized EOC treatment strategies. Considering the study period (2000–2019), the limited use of bevacizumab and poly (ADP‐ribose) polymerase inhibitors as maintenance therapy should be recognized.

Clinical features and impact of p53 status on sporadic mismatch repair deficiency and Lynch syndrome in uterine cancer

AbstractThe clinical features of sporadic mismatch repair deficiency (MMRd) and Lynch syndrome (LS) in Japanese patients with endometrial cancer (EC) were examined by evaluating the prevalence and prognostic factors of LS and sporadic MMRd in patients with EC. Targeted sequencing of five LS susceptibility genes (MLH1, MSH2, MSH6, PMS2, and EPCAM) was carried out in 443 patients with EC who were pathologically diagnosed with EC at the National Cancer Center Hospital between 2011 and 2018. Pathogenic variants in these genes were detected in 16 patients (3.7%). Immunohistochemistry for MMR proteins was undertaken in 337 of the 433 (77.9%) EC patients, and 91 patients (27.0%) showed absent expression of at least one MMR protein. The 13 cases of LS with MMR protein loss (93.8%) showed a favorable prognosis with a 5‐year overall survival (OS) rate of 100%, although there was no statistically significant difference between this group and the sporadic MMRd group (p = 0.27). In the MMRd without LS group, the 5‐year OS rate was significantly worse in seven patients with an aberrant p53 expression pattern than in those with p53 WT (53.6% vs. 93.9%, log‐rank test; p = 0.0016). These results suggest that p53 abnormalities and pathogenic germline variants in MMR genes could be potential biomarkers for the molecular classification of EC with MMRd.