Literature DB >> 29986113

National survey of intracavitary brachytherapy for intact uterine cervical cancer in Japan.

Takafumi Toita1, Tatsuya Ohno2, Hitoshi Ikushima3, Tetsuo Nishimura4, Takashi Uno5, Kazuhiko Ogawa6, Hiroshi Onishi7, Takushi Dokiya8, Jun Itami9.   

Abstract

To review the current status of, and labor expended for (in terms of time required), intracavitary brachytherapy (ICBT) in definitive radiotherapy/chemoradiotherapy for cervical cancer patients, two national surveys were performed. The first survey was conducted between July and August 2016 and consisted of a questionnaire of 12 items regarding ICBT procedures for cervical cancer, which was sent to 173 centers installed with high-dose-rate remote after-loading brachytherapy systems. Between November and December 2016, another survey was performed in 79 centers to evaluate labor required for ICBT procedures in terms of time spent and number of staff involved. In the first survey, the response rate was 77% of the 173 centers. ICBT was performed for cervical cancer in 118 (89%) centers. Imaging modalities used after applicator insertion were X-ray alone in 46 (40%), computed tomography in 69 (60%) and magnetic resonance imaging in 5 (4%) centers. Three-dimensional (3D) planning was performed in 55 centers (48%). Fifty-five (70%) centers responded to the second survey regarding ICBT-mandated labor. The median cumulative duration of the entire ICBT procedure was 330 min (the sum of the times spent by each staff member) and was longer in the 3D image-guided brachytherapy (3D-IGBT) (405 min) than in the X-ray group (230 min). This trend was significant for the specific processes of image acquisition and treatment planning, especially for radiation oncologists. In definitive radiotherapy/chemoradiotherapy for cervical cancer patients, 3D-IGBT use has been gradually spreading in Japan. The present survey revealed that ICBT, especially 3D-IGBT, requires substantial labor and time from staff.

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Mesh:

Year:  2018        PMID: 29986113      PMCID: PMC6054170          DOI: 10.1093/jrr/rry035

Source DB:  PubMed          Journal:  J Radiat Res        ISSN: 0449-3060            Impact factor:   2.724


INTRODUCTION

In the past few decades, the prevalence of uterine cervical cancer has been increasing, especially in young women in Japan [1]. In clinical practice in Japan, radical hysterectomy with/without postoperative adjuvant treatment has been the first treatment of choice for operable Stage I–IIB patients for a long time [2]. Recently, clinical application of definitive radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) has been increasing for patients with bulky tumors or Stage IIB disease as well as Stage III and IVA patients [2] according to the current guidelines [3, 4]. Definitive RT/CCRT for cervical cancer patients consists of external beam radiotherapy (EBRT) and intracavitary brachytherapy (ICBT). Excellent oncologic outcomes with acceptable toxicities after RT/CCRT have been reported. Recently, some physicians have been applying highly precise EBRT, such as intensity-modulated radiotherapy (IMRT) and stereotactic body radiotherapy (SBRT) as alternative treatments to ICBT. However, data from the National Cancer Database indicated that IMRT/SBRT as a boost is associated with significantly poorer oncologic outcomes compared with ICBT [5]. The NCCN Clinical Practice Guidelines in Oncology for Cervical Cancer, version 1.2018, clearly state that ‘conformal external beam radiotherapies (such as IMRT) should not be used as routine alternatives to brachytherapy for treatment of central disease of an intact cervix’ [3]. Therefore, it is very important to appropriately provide ICBT as an essential treatment for definitive RT/CCRT for cervical cancer patients. ICBT requires substantial labor and time from multidisciplinary medical staff. A shortage of staff is one of the major issues in most Japanese radiotherapy centers. Recently, treatment planning for ICBT has shifted rapidly and globally from 2D to 3D modalities, belatedly to EBRT [6-10]. Three-dimensional image-guided ICBT (3D-IGBT) can be individualized according to the tumor size/shape and anatomy of each patient, while minimizing the dose to surrounding normal organs. As a result, improved oncologic outcomes as well as decreasing toxicities of 3D-IGBT compared with 2D-ICBT have been reported [11, 12]. However, clinical dissemination of 3D-IGBT has been slow and limited in Japan [13], probably because of the abovementioned structural issues in Japanese radiotherapy centers. A working group was organized by the Japanese Group of Brachytherapy/Japan Society for Radiation Oncology in 2016 to review the current status of ICBT and its associated issues in Japan. In this paper, we will present the results from surveys performed by the working group and attempt to propose solutions for the issues identified.

MATERIALS AND METHODS

A survey regarding intracavitary brachytherapy performance

A questionnaire containing 12 items regarding ICBT procedures for cervical cancer (Appendix 1) was sent by postal mail to 173 radiotherapy centers installed with high-dose-rate (HDR) remote after-loading brachytherapy systems (RALSs) installed. A list of these centers was provided by the Database Committee of the Japan Society for Radiation Oncology (JASTRO). The survey was conducted between July and August 2016.

Measurement of labor expended during the intracavitary brachytherapy procedure

Another survey was conducted to measure the labor required by staff involved in ICBT procedures that use tandem and ovoid applicators for patients treated with definitive RT/CCRT. Cases of postoperative ICBT (using a vaginal cylinder or ovoid applicators alone) and ICBT with interstitial needles were excluded from the evaluation. Between November and December 2016, measurements were conducted at 79 centers that accepted our request at the time of the first questionnaire survey. The centers and cases were divided into two groups according to the type of imaging conducted after applicator insertion: X-rays only (X-ray group) and computed tomography (CT) and/or magnetic resonance imaging (MRI) (3D-IGBT group). The survey was performed between November and December 2016. Each center was asked to record the actual time in minutes and number of staff members (radiation oncologist, radiotherapist, medical physicist, and nurse) involved in each process of ICBT. The processes included preparation before the patient entered the HDR-RALS suite, preparation after the patient entered, applicator insertion, image acquisition, treatment planning, treatment (source delivery), applicator removal, and clean-up after treatment. Times were measured for one to three ICBT interventions at each center. The total time in minutes for each process was calculated as the sum of the times spent by each staff member involved in the procedure. For radiation oncologists, the values used to rank the physician’s experience were multiplied by the actual times measured. The physician experience values were proposed by the Japanese Health Insurance Federation for Surgery (2014) as follows: 1 for physicians with 1–4 years, 1.238 for those with 5–9 years, 1.52 for those with 10–14 years, and 1.747 for those with over 15 years of experience [14].

RESULTS

A survey of intracavitary brachytherapy performance

Of the 173 centers contacted in the first survey, 133 (77%) responded and completed the questionnaires. The results were analyzed in October 2016.

Outline

ICBT in definitive RT/CCRT for cervical cancer was performed at 118 (89%) of the 133 centers. Figure 1 shows the distribution of the centers according to the total number of patients treated with ICBT per year. The median numbers of patients and ICBT treatment sessions per year were 18 (range: 1–126) and 59 (range: 2–378), respectively. The mean numbers of ICBT fractions per patient were three in 20 centers, four in 74 centers, five in 9 centers, six in 4 centers, three or four in 7 centers, two to four in 2 centers, and five or six in 1 center.
Fig. 1.

Numbers of centers according to the total number of patients treated with intracavitary brachytherapy (ICBT) per year (n = 111). Patients treated with ICBT postoperatively (using a vaginal cylinder or ovoid applicator alone) were excluded.

Numbers of centers according to the total number of patients treated with intracavitary brachytherapy (ICBT) per year (n = 111). Patients treated with ICBT postoperatively (using a vaginal cylinder or ovoid applicator alone) were excluded.

Methods of treatment planning

Figure 2 shows the imaging modalities and planning methods utilized for ICBT. In the analysis, 3D-planning was based on both high-risk clinical target volume (HR-CTV) contouring and dose evaluation using dose–volume histogram (DVH) parameters, while 2D-planning was based on X-rays and/or CT images, but prescription and evaluation were based on points alone (e.g. point A and other reference points). In the survey, 46 of 115 (40%) centers responded that they utilized X-rays alone for ICBT planning. In 69 (60%) centers, CT images were acquired after applicator insertion. 3D-planning was performed in 55 (48%) of 115 centers, of which 5 (4%) also acquired and utilized MRI for 3D-planning. Of the 55 centers that perform 3D-planning, 46 (84%) responded that 3D-planning is performed during every ICBT session. Of the 69 centers using CT, 30 (43%) have CT scanners installed in the same suite as the HDR-RALS machine. Of the 46 centers that use X-rays only, 24 (52%) plan to start 3D-IGBT within 3 years.
Fig. 2.

Acquired imaging modalities and treatment methods for ICBT (n = 115).

Acquired imaging modalities and treatment methods for ICBT (n = 115).

Physician-reported issues with the reimbursement system for intracavitary brachytherapy services for cervical cancer

Table 1 lists the issues regarding reimbursement for ICBT services reported by physicians in the survey. Most physicians responded that the current reimbursement system for ICBT was insufficient for various reasons.
Table 1.

Issues regarding reimbursement for ICBT costs for cervical cancer

IssuesNumber of centers
Low reimbursement for treatment35
Low reimbursement for management30
Limited number of times to calculate management feea31
Low reimbursement for source replacement24
None4

Multiple answers were allowed. ICBT = intracavitary brachytherapy.

aIn the current rule, the calculation is permited twice in maximum.

Issues regarding reimbursement for ICBT costs for cervical cancer Multiple answers were allowed. ICBT = intracavitary brachytherapy. aIn the current rule, the calculation is permited twice in maximum.

A survey of the labor expended during intracavitary brachytherapy

Fifty-five (70%) centers responded and provided data from 146 ICBT sessions. The characteristics of the patients who were monitored and the time spent conducting the ICBT procedures are shown in Table 2. In the 3D-IGBT group, 3D-planning was performed in 81 patients (87%). The median total duration for all ICBT process was 147 min. The duration was longer in the 3D-IGBT group (155 min) compared with in the X-ray group (141 min). Figure 3 shows the median duration for each specific process of ICBT. The numbers of staff involved in each ICBT process are shown in Table 3. For some processes (preparation after the patient entry, applicator insertion, image acquisition, and treatment planning), the numbers of radiation oncologists involved were greater in the 3D-IGBT group compared with in the X-ray group. In contrast, no significant difference in the number of radiotherapists/medical physicists or nurses was observed between the groups. The cumulative time spent by all staff members in all ICBT processes was 330 min. The cumulative time spent was longer in the 3D-IGBT group (405 min) than in the X-ray group (230 min). Figure 4 shows the cumulative time spent by all staff during each ICBT process. Other than the specific processes of treatment delivery and post-treatment, longer times were observed in the 3D-IGBT than in the X-ray group. Tables 4–6 show the median cumulative time spent for each procedure according to occupation. Although a similar trend was observed for radiation oncologists as that for overall staff, there were no differences between the X-ray and 3D-IGBT groups in the other staff categories. Seven patients from three centers were treated with MRI-based IGBT. The median cumulative time spent by staff on these seven patients was 911 min: 471 min by radiation oncologists and 440 min by other staff. Substantial differences were observed in the process of applicator insertion (3D-IGBT overall: 69 min, MRI-based: 171 min), image acquisition (3D-IGBT overall: 50 min, MRI-based: 185 min) and treatment planning (3D-IGBT overall: 98 min, MRI-based: 194 min).
Table 2.

Characteristics of patients who were monitored and the times required for ICBT

Total (n = 146)X-rays (n = 53)3D-IGBT (n = 93)
FIGO stage
 I331122
 II461927
 III451629
 IV16610
 Unknown615
Age (median)65 (25–93)65 (25–93)65 (29–86)
Sedation/analgesia
 IV conscious711952
 General anesthesia909
 Oral/suppository532726
 None862
 Unknown514

ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy, IV = intravenous.

Fig. 3.

Median duration for each specific ICBT process (n = 146).

Table 3.

Mean numbers of staff involved in each ICBT process (range)

ProcessTotal (n = 146)X-rays (n = 53)3D-IGBT (n = 93)
Preparation before the patient entry
 RO0.9 (0–3)0.8 (0–2)0.9 (0–3)
 RT/P1 (0–2)0.9 (0–2)1 (0–2)
 N1.1 (0–2)1.1 (0–2)1.2 (0–2)
Preparation after the patient entry
 RO0.9 (0–4)0.6 (0–4)1.2 (0–4)
 RT/P0.8 (0–2)0.8 (0–2)0.8 (0–2)
 N1.3 (1–2)1.2 (1–2)1.3 (1–2)
Applicator insertion
 RO1.6 (1–4)1.35 (1–3)1.8 (1–4)
 RT/P0.8 (0–3)0.8 (0–3)0.8 (0–3)
 N1.2 (0–2)1.1 (0–2)1.3 (1–2)
Image acquisition
 RO1.3 (0–4)0.9 (0–3)1.4 (0–4)
 RT/P1.5 (1–3)1.5 (1–3)1.5 (1–3)
 N0.9 (0–2)0.6 (0–2)1 (0–2)
Treatment planning
 RO1.4 (0–3)1.2 (0–3)1.6 (1–3)
 RT/P1.6 (0–3)1.6 (0–3)1.6 (0–3)
 N0.5 (0–2)0.4 (0–1)0.6 (0–2)
Treatment (delivery)
 RO1.3 (0–4)1.3 (0–4)1.3 (0–3)
 RT/P1.5 (0–3)1.6 (1–3)1.5 (0–2)
 N1.5 (0–3)1.6 (1–3)1.5 (0–2)
Applicator removal
 RO1.4 (1–4)1,5 (1–4)1.2 (1–3)
 RT/P0.7 (0–2)0.6 (0–2)0.7 (0–2)
 N1.1 (0–2)1.2 (1–2)1.1 (0–2)
Post-treatment
 RO0.1 (0–2)00.2 (0–2)
 RT/P0.5 (0–2)0.5 (0–2)0.5 (0–2)
 N1.2 (0–3)1.2 (0–2)1.2 (1–3)

RO = radiation oncologist, RT/P = radiotherapist and/or medical physicist, N = nurse.

Fig. 4.

Median cumulative times spent by all staff during each ICBT process (n = 146). The ‘cumulative times’ refers to the sum of the times spent by each staff member involved.

Table 4.

Median time expended by radiaton oncologists during each ICBT process (min)

ProcessTotala (n = 146)X-raysa (n = 53)3D-IGBTa (n = 93)
Preparation before the patient entry000
Preparation after the patient entry9016
Applicator insertion362839
Image acquisition18925
Treatment planning42955
Treatment (delivery)252225
Applicator removal171218
Post-treatment000
Total14780178

ICBT = intracavitary brachytherapy, 3D-IGBT = three dimensional image-guided brachytherapy.

aSum of the times required by each staff involved in the procedure.

Table 6.

Median time expended by nurses during each ICBT process (min)

ProcessTotala (n = 146)X-raysa (n = 53)3D-IGBTa (n = 93)
Preparation before the patient entry201530
Preparation after the patient entry151215
Applicator insertion202020
Image acquisition7310
Treatment planning000
Treatment (delivery)131114
Applicator removal101010
Post-treatment201520
Total10586119

ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy.

aSum of the times required by each staff involved in the procedure.

Characteristics of patients who were monitored and the times required for ICBT ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy, IV = intravenous. Median duration for each specific ICBT process (n = 146). Mean numbers of staff involved in each ICBT process (range) RO = radiation oncologist, RT/P = radiotherapist and/or medical physicist, N = nurse. Median cumulative times spent by all staff during each ICBT process (n = 146). The ‘cumulative times’ refers to the sum of the times spent by each staff member involved. Median time expended by radiaton oncologists during each ICBT process (min) ICBT = intracavitary brachytherapy, 3D-IGBT = three dimensional image-guided brachytherapy. aSum of the times required by each staff involved in the procedure. Median time expended by radiotherapists and/or medical physicists during each ICBT process (min) ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy. aSum of the times required by each staff involved in the procedure. Median time expended by nurses during each ICBT process (min) ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy. aSum of the times required by each staff involved in the procedure.

DISCUSSION

The present study demonstrated the current status of and issues regarding ICBT for patients with uterine cervical cancer in Japan. As shown in Table 7, whereas the dissemination of 3D-IGBT in Japan has been slow compared with in other developed countries, current research has revealed that the number of centers applying 3D-IGBT has been increasing gradually [13]. Further expansion is expected over the next few years. The GEC-ESTRO guidelines and experts from overseas recommend the use of MRI for 3D-IGBT [15, 16]. However, our survey showed that only 4% of centers in Japan perform MRI-based IGBT.
Table 7.

ICBT treatment planning for cervical cancer

SurveillanceNumber2D-ICBT3D-IGBT
CountryYearof centersX-rayCTMRI
US [6, 7]200713343%55%2%
201421915%95%34%
Canada [8, 9]20092250%45%5%
20122421%75%38%
2015284%96%57%
The Netherlands [10]2015160%55%100%
Japan [13] (present study)201217180%14%1%
201613340%44%4%

ICBT = intracavitary brachytherapy, IGBT = image-guided intracavitary brachytherapy, CT = computed tomography, MRI = magnetic resonance imaging.

ICBT treatment planning for cervical cancer ICBT = intracavitary brachytherapy, IGBT = image-guided intracavitary brachytherapy, CT = computed tomography, MRI = magnetic resonance imaging. In addition to the questionnaire survey, we performed another survey to measure the labor required for ICBT procedures. This investigation demonstrated that the level of labor, which was expressed as the time required by staff, to perform ICBT procedures was large. The survey also revealed that 3D-IGBT required more time than did X-ray-based ICBT, especially for treatment planning. Although the data were limited, the study showed that the labor required for MRI-based IGBT is substantial. These findings suggest that there are some barriers to utilizing ICBT, especially 3D-IGBT, in Japanese radiotherapy centers because of limited man-power and time. Whereas some centers employ MRI-based IGBT [17], most centers cannot afford to do so. For such situations in Japan, consensus-based recommendations for HR-CTV with CT were recently developed to minimize the variation in CT-based HR-CTV and deviation from MRI-based HR-CTV [18]. Besides these issues of man-power and machine operation time, the high cost necessary for installing and maintaining the HDR-brachytherapy system is another major challenge. The current reimbursement system is far from sufficient to cover the full costs of ICBT, especially 3D-IGBT. In our present questionnaire survey, opinions regarding reimbursement issues for ICBT for cervical cancer were also assessed. Most centers indicated problems relating to the treatment fees and reimbursement funds. In a Korean survey, similar to our results, 27 of 28 centers indicated that they encounter difficulties in maintaining their brachytherapy facilities [19]. That Korean study also reported that the number of centers installing HDR-brachytherapy systems decreased by 28.2% from 2006 to 2014, while the number of total radiotherapy systems increased. According to the Korean Central Cancer Registry, the age-standardized incidence rate of cervical cancer per 100 000 persons decreased from 16.3 in 1999 to 10.6 in 2010 [19]. In contrast, this figure increased from 7.0 in 1999 to 11.2 in 2010 in Japan [1]. This suggests that a decrease in the number of institutions housing HDR-brachytherapy systems would be a more serious problem in Japan than in Korea. To overcome this issue, increasing the reimbursement funds for ICBT, especially 3D-IGBT, is essential. Recently, Bauer-Nilsen and their colleagues reported the costs of administering brachytherapy and EBRT using a time-driven activity-based costing methodology [20]. They compared the costs with the United States Medicare reimbursement and relative value units (RVUs) [20]. They demonstrated that brachytherapy is costlier to deliver and requires more time from the attending radiation oncologist and medical physicist compared with EBRT, and their analyses of the reimbursement indicated the payments to physicians do not account for the substantial time requirements and expertise in the USA [20]. In our present analyses, actual costs and reimbursement in yen and/or US dollars were not estimated. Future research is needed to suggest the appropriate reimbursement for conducting steady ICBT performance for cervical cancer patients in Japan. From the perspective of efficiency, limiting ICBT treatment to specialized centers housing HDR-brachytherapy systems may be an appropriate future direction. However, that should be carefully discussed before execution. First, it would be essential for patients who receive EBRT in radiotherapy departments lacking brachytherapy equipment to be transferred to HDR-brachytherapy centers smoothly and securely. Prolonging the overall treatment time negatively affects oncologic outcomes in cervical cancer patients treated with definitive RT/CCRT [21, 22]. Second, the number of patients who receive an EBRT boost (e.g. IMRT or SBRT) as an alternative to ICBT may increase. Third, it is mandatory to ensure sufficient manpower in centers performing HDR-brachytherapy where patients would be transferring from other institutions. Therefore, adequate reimbursement to sufficiently cover labor costs, including those for quality assurance, would be particularly important in these centers. In summary, the present study demonstrated that the use of 3D-IGBT in definitive RT/CCRT for patients with cervical cancer is gradually spreading in Japan. The survey also revealed that ICBT, especially 3D-IGBT, requires substantial labor and time from various staff members. These results suggest that adequate reimbursement is crucial for providing ICBT as an essential treatment for definitive RT/CCRT for cervical cancer patients.

ACKNOWLEDGEMENTS

The authors thank all staff members of the Japanese radiation oncology centers who kindly responded to the surveys. Results from this research were presented at the 30th Annual Meeting of the Japanese Society for Radiation Oncology, Osaka, November 17–19, 2017.

CONFLICTS OF INTEREST

The authors have no conflicts of interest to disclose.

FUNDING

This work was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI [Grant No. JP16K10398].
Table 5.

Median time expended by radiotherapists and/or medical physicists during each ICBT process (min)

ProcessTotala (n = 146)X-raysa (n = 53)3D-IGBTa (n = 93)
Preparation before the patient entry151215
Preparation after the patient entry555
Applicator insertion5010
Image acquisition151015
Treatment planning302630
Treatment (delivery)172015
Applicator removal204
Post-treatment000
Total897394

ICBT = intracavitary brachytherapy, 3D-IGBT = three-dimensional image-guided brachytherapy.

aSum of the times required by each staff involved in the procedure.

  18 in total

1.  Recommendations from gynaecological (GYN) GEC ESTRO working group (II): concepts and terms in 3D image-based treatment planning in cervix cancer brachytherapy-3D dose volume parameters and aspects of 3D image-based anatomy, radiation physics, radiobiology.

Authors:  Richard Pötter; Christine Haie-Meder; Erik Van Limbergen; Isabelle Barillot; Marisol De Brabandere; Johannes Dimopoulos; Isabelle Dumas; Beth Erickson; Stefan Lang; An Nulens; Peter Petrow; Jason Rownd; Christian Kirisits
Journal:  Radiother Oncol       Date:  2006-01-05       Impact factor: 6.280

2.  Japan Society of Gynecologic Oncology guidelines 2011 for the treatment of uterine cervical cancer.

Authors:  Yasuhiko Ebina; Nobuo Yaegashi; Hidetaka Katabuchi; Satoru Nagase; Yasuhiro Udagawa; Toru Hachisuga; Tsuyoshi Saito; Mikio Mikami; Yoichi Aoki; Hiroyuki Yoshikawa
Journal:  Int J Clin Oncol       Date:  2015-03-24       Impact factor: 3.402

3.  The effect of treatment time in locally advanced cervical cancer in the era of concurrent chemoradiotherapy.

Authors:  Suisui Song; Sonali Rudra; Michael D Hasselle; Paige L Dorn; Loren K Mell; Arno J Mundt; S Diane Yamada; Nita K Lee; Yasmin Hasan
Journal:  Cancer       Date:  2012-07-17       Impact factor: 6.860

4.  Improved survival of patients with cervical cancer treated with image-guided brachytherapy compared with conventional brachytherapy.

Authors:  E C Rijkmans; R A Nout; I H H M Rutten; M Ketelaars; K J Neelis; M S Laman; V L M A Coen; K N Gaarenstroom; J R Kroep; C L Creutzberg
Journal:  Gynecol Oncol       Date:  2014-08-27       Impact factor: 5.482

5.  Image-guided brachytherapy for cervical cancer: a Canadian Brachytherapy Group survey.

Authors:  Simon Pavamani; David P D'Souza; Lorraine Portelance; Peter S Craighead; Andrew G Pearce; Laurel L Traptow; Corinne M Doll
Journal:  Brachytherapy       Date:  2011-02-23       Impact factor: 2.362

6.  Evaluation of Delivery Costs for External Beam Radiation Therapy and Brachytherapy for Locally Advanced Cervical Cancer Using Time-Driven Activity-Based Costing.

Authors:  Kristine Bauer-Nilsen; Colin Hill; Daniel M Trifiletti; Bruce Libby; Donna H Lash; Melody Lain; Deborah Christodoulou; Constance Hodge; Timothy N Showalter
Journal:  Int J Radiat Oncol Biol Phys       Date:  2017-09-14       Impact factor: 7.038

Review 7.  Image-Based Brachytherapy for the Treatment of Cervical Cancer.

Authors:  Matthew M Harkenrider; Fiori Alite; Scott R Silva; William Small
Journal:  Int J Radiat Oncol Biol Phys       Date:  2015-07-15       Impact factor: 7.038

8.  Patterns of care survey: Radiotherapy for women with locally advanced cervical cancer.

Authors:  Peter de Boer; Ina M Jürgenliemk-Schulz; Henrike Westerveld; Astrid A C de Leeuw; Raquel Dávila-Fajardo; Coen R N Rasch; Bradley R Pieters; Lukas J A Stalpers
Journal:  Radiother Oncol       Date:  2017-04-20       Impact factor: 6.280

9.  Recommendations for high-risk clinical target volume definition with computed tomography for three-dimensional image-guided brachytherapy in cervical cancer patients.

Authors:  Tatsuya Ohno; Masaru Wakatsuki; Takafumi Toita; Yuko Kaneyasu; Ken Yoshida; Shingo Kato; Noriko Ii; Sunao Tokumaru; Hitoshi Ikushima; Takashi Uno; Shin-Ei Noda; Tomoko Kazumoto; Yoko Harima
Journal:  J Radiat Res       Date:  2017-05-01       Impact factor: 2.724

10.  A questionnaire-based survey on 3D image-guided brachytherapy for cervical cancer in Japan: advances and obstacles.

Authors:  Tatsuya Ohno; Takafumi Toita; Kayoko Tsujino; Nobue Uchida; Kazuo Hatano; Tetsuo Nishimura; Satoshi Ishikura
Journal:  J Radiat Res       Date:  2015-08-11       Impact factor: 2.724

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Authors:  Yuki Otani; Tatsuya Ohno; Ken Ando; Kazutoshi Murata; Shingo Kato; Shin-Ei Noda; Keiko Murofushi; Hiroki Ushijima; Daisaku Yoshida; Noriyuki Okonogi; Fumiaki Isohashi; Masaru Wakatsuki; Takashi Nakano
Journal:  J Radiat Res       Date:  2021-05-12       Impact factor: 2.724

2.  Vaginal Fistulas of the Bladder and Small Bowel After Two-Dimensional Intracavitary Brachytherapy in a Patient With Cervical Cancer.

Authors:  Yuki Yamada; Natsuo Tomita; Yuto Kitagawa; Mikiko Imai; Mitsuaki Ito
Journal:  Cureus       Date:  2020-11-17

3.  Small dose of oral gastrografin for computed tomography-based image-guided brachytherapy in patients with uterine cervical cancer.

Authors:  Hitoshi Maemoto; Takuto Ogura; Takafumi Toita; Takuro Ariga; Seiji Hashimoto; Yuka Kawakami; Kazuki Ishikawa; Shota Takehara; Joichi Heianna; Wataru Kudaka; Yoichi Aoki; Akihiro Nishie
Journal:  J Radiat Res       Date:  2022-01-20       Impact factor: 2.724

Review 4.  Combined Interstitial and Intracavitary High-Dose Rate Brachytherapy of Cervical Cancer.

Authors:  Jun Itami; Naoya Murakami; Miho Watanabe; Shuhei Sekii; Takahiro Kasamatsu; Shingo Kato; Hisako Hirowatari; Hitoshi Ikushima; Ken Ando; Tatsuya Ohno; Hiroyuki Okamoto; Kae Okuma; Hiroshi Igaki
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Review 5.  Global challenges of radiotherapy for the treatment of locally advanced cervical cancer.

Authors:  Jyoti S Mayadev; Guihao Ke; Umesh Mahantshetty; Marcos David Pereira; Rafal Tarnawski; Takafumi Toita
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6.  A novel intra pre-plan method of interstitial needle optimization for cervical cancer patients treated with Venezia applicator brachytherapy: a technical note.

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Journal:  J Contemp Brachytherapy       Date:  2022-06-08

7.  Definitive radiotherapy consisting of whole pelvic radiotherapy with no central shielding and CT-based intracavitary brachytherapy for cervical cancer: feasibility, toxicity, and oncologic outcomes in Japanese patients.

Authors:  Takeaki Kusada; Takafumi Toita; Takuro Ariga; Wataru Kudaka; Hitoshi Maemoto; Wataru Makino; Kazuki Ishikawa; Joichi Heianna; Yutaka Nagai; Yoichi Aoki; Sadayuki Murayama
Journal:  Int J Clin Oncol       Date:  2020-08-27       Impact factor: 3.402

  7 in total

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