Investigator

Kenro Chikazawa

Jichi Medical University

KCKenro Chikazawa
Papers(8)
Oncological safety of…Pegfilgrastim Maintai…Adjuvant chemotherapy…What Is the Future of…Three-Dimensional Per…Importance of conizat…Improved bladder func…Volume Index Measured…
Collaborators(7)
Tomoyuki KuwataKen ImaiRyo KonnoHiroyoshi KoShin TakanekaNatsuki OsawaKoji Matsumoto
Institutions(3)
Jichi Medical Univers…Showa UniversityShowa University

Papers

Oncological safety of minimally invasive surgery in borderline ovarian tumor and ovarian cancer: a retrospective comparative study

This study aimed to evaluate the oncological safety of laparoscopic surgery for patients with benign tumors who underwent laparoscopic surgery at our facility and were subsequently diagnosed with borderline ovarian tumors or ovarian cancer. We conducted a retrospective review of 45 patients initially diagnosed with benign ovarian tumors who underwent laparoscopic surgery at our institution from January 2009 to April 2024. Postoperative pathological examination identified 32 cases of borderline ovarian tumors and 13 cases of ovarian cancer. Laparoscopic cystectomy was performed in 14 (43.8%) borderline cases and 4 (30.8%) ovarian cancer cases. Out of 14 patients with borderline ovarian tumors who underwent cystectomy, 8 subsequently underwent staging laparotomy, whereas 6 underwent only ovarian tumor cystectomy. In contrast, none of the patients with ovarian cancer completed treatment with only ovarian tumor cystectomy. Recurrent disease was observed in 9.4% of borderline tumor cases, all of which were successfully managed with further surgery. In the ovarian cancer group, recurrence occurred in 31% of patients, with 3 resulting in tumor-related mortality. Laparoscopic surgery for borderline ovarian tumors is suggested to be oncologically safe, with low recurrence rate and no adverse impact on survival. However, for ovarian cancer, particularly in cases with peritoneal dissemination, rapid disease progression remains a concern. While this study suggests that laparoscopic surgery may be a viable option for borderline ovarian tumors, further research is needed to validate these findings, particularly for ovarian cancer.

Adjuvant chemotherapy after radical hysterectomy yields comparable outcomes to chemoradiation for stage IB2-IIB and IIIC1-2 cervical cancer: a single-center retrospective study

This study aimed to evaluate and compare recurrence-free survival (RFS) between radical hysterectomy followed by adjuvant chemotherapy and initial chemoradiotherapy for cervical cancer at our institution. In this retrospective study, we enrolled patients diagnosed with stage IB2-IIB cervical cancer according to the International Federation of Gynecology and Obstetrics 2018 staging system, who underwent either radical hysterectomy with pelvic lymphadenectomy followed by adjuvant chemotherapy or initial concurrent chemoradiation at our institution between 2009 and 2022. Among these patients, 74 and 110 underwent radical hysterectomy and chemoradiation, respectively. The radical hysterectomy group exhibited significantly improved RFS compared with the chemoradiation group; however, no significant difference was observed in overall survival between the groups. Cox hazard analysis for RFS showed that, among the clinical risk factors identified before the initial treatment, only parametrial invasion was statistically significant. No significant difference in RFS was observed between the radical hysterectomy group and chemoradiation group. Regarding recurrence patterns, para-aortic lymph node recurrence occurred significantly more frequently in the chemoradiation group than in the radical hysterectomy group. Postoperative ureteral injury was reported in once case and postoperative ureteral stenosis in 2 cases in the radical hysterectomy group. In contrast, vesicovaginal fistula and rectovaginal fistula were reported in one case each in the chemoradiation group. Radical hysterectomy followed by adjuvant chemotherapy provided RFS outcomes comparable to those achieved with initial chemoradiotherapy for stage IB2-IIB and IIIC1-2 cervical cancer. These findings suggest that both approaches are viable, although further prospective studies are needed.

Improved bladder function in radical hysterectomy without worsening oncologic outcome: resection of the posterior layer of the vesicouterine ligament with the procedure limited to the vesical veins

The classic Okabayashi nerve-sparing radical hysterectomy involves complete resection of the posterior leaf of the vesicouterine ligament, whereas in the simplified nerve-sparing radical hysterectomy, only the vesical veins and some connective tissue of the posterior layer of the vesicouterine ligament are resected. This study aimed to compare bladder function and cervical carcinoma relapse-free survival between these two techniques. We conducted a retrospective, historical control study. All female patients aged >20 years who were diagnosed with cervical cancer stage IB1-IIB and underwent radical hysterectomy with pelvic lymphadenectomy between 2009 and 2022 were enrolled. Patients who had a history of other cancers and those who were treated with non-surgical approaches or non-radical hysterectomy were excluded. The primary outcome was relapse-free survival during the follow-up period. A total of 114 patients who underwent curative-intent radical hysterectomy were included in this study. The median follow-up duration was 60 months. No significant difference was observed in relapse-free survival between the two surgical procedures. The simplified nerve-sparing radical hysterectomy was superior in terms of both motor and sensory bladder function outcomes. Resection of the posterior layer of the vesicouterine ligament, with the procedure limited to the vesical veins, is an effective and safe method for radical hysterectomy. It may be more useful for preserving the bladder function, without leading to unfavorable oncologic outcomes.

Volume Index Measured Using Magnetic Resonance Imaging for Diagnosing Cervical Cancer Tumors <2 cm

Diagnosis of cervical cancer with tumor diameter <2 cm using magnetic resonance imaging alone has not been investigated. Moreover, whether tumor volume can be used for diagnosing the true tumor diameter remains unknown. Here, we investigated the utility of early cervical cancer volume index in diagnosing cervical cancer with a tumor diameter of <2 cm, which can be treated using more conservative surgery. This single-center retrospective study analyzed women who underwent radical hysterectomy for cervical cancer with a tumor diameter of <2 cm and clinical stages IA2, IB1, IB2, IB3, and IIA1 at our institute between January 2009 and April 2022. The volume index, defined as the product of the maximum longitudinal diameter along the uterine axis, maximum anteroposterior diameter (thickness) on a sagittal section image, and maximum horizontal diameter on a horizontal section image, was evaluated using either T2-weighted magnetic resonance imaging or gadolinium-enhanced T1-weighted imaging. The receiver operating characteristic curve for the volume index was also calculated. The sensitivity and specificity of magnetic resonance imaging for measuring the tumor diameter were 0.92 and 0.84, respectively. The calculated cut-off value was 2.60, whereas the volume index area under the curve was 0.955, with a sensitivity of 0.92 and specificity of 0.93. Considering the specificity and low incidence of false-negative results, the volume index can be used for preoperative diagnosis of pT1B1 cervical cancer, which can be treated with more conservative surgery.

8Papers
7Collaborators
Uterine Cervical NeoplasmsNeoplasm StagingDisease-Free SurvivalEndometriosisOvarian NeoplasmsGenital Neoplasms, FemaleStomach Neoplasms