A Prospective Cohort Study to Compare Treatment Results Between 2 Fractionation Schedules of High-Dose-Rate Intracavitary Brachytherapy (HDR-ICBT) in Patients With Cervical Cancer

A comparative study between two different dose fractionation schedules of cobalt-60-based HDR intracavitary brachytherapy in carcinoma cervix stages IIB-IIIC1

INTRODUCTION

High dose rate (HDR) intracavitary brachytherapy (ICBT) is an integral element in the treatment of carcinoma uterine cervix. The main objective of brachytherapy in carcinoma cervix is to deliver a lethal dose to tumor cells without inducing unacceptable damage to the surrounding normal tissue. Because the absorbed dose falls off rapidly, higher doses can be safely delivered to the targeted tissue over a short time. The quest for optimum dose and fractionation schedule in HDR ICBT is still ongoing, and there is no uniform consensus. This study aimed to assess the acute dose-related toxicities of HDR brachytherapy schedule of 7 Gy x 3 fractions over 6 Gy x 4 fractions in the treatment of cervical cancer.

OBJECTIVE

The aim of this study was to study the acute treatment-related gastrointestinal (GI) and genitourinary (GU) toxicities between two HDR brachytherapy regimens.

MATERIAL AND METHODS

This is a prospective institutional study carried out from May 2018 to September 2018. In this time period, 66 patients of cervical cancers fulfilling our inclusion criteria were treated with concurrent chemoradiation (CCRT) following brachytherapy. During treatment, patients were randomized to arm A-7 Gy per fraction for three fractions and arm B-6 Gy per fraction for four fractions. Acute GI and GU toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE) Version 4.03. All patients were kept for follow-up for 3 months in this study.

RESULTS

There is no statistically significant difference between the two arms for acute GI and GU toxicities, and the results were comparable.

CONCLUSIONS

Considering the increased hospital burden of locally advanced cervical cancer patients in the Indian context, the HDR brachytherapy schedule of 7 Gy per fraction is preferable to 6 Gy per fraction for a lesser fractionation schedule.

Outcomes from a 3-fraction high-dose-rate brachytherapy regimen for patients with cervical cancer

PURPOSE

To estimate local control, survival, and toxicity associated with a 3-fraction (3F) image-guided brachytherapy (IGBT) regimen compared to longer fraction (LF) for cervical cancer.

METHODS

150 patients treated between 2015-2020 with 3F (24Gy in 3 fractions) or LF (28...30 Gy in 4-5 fractions) were reviewed. The primary outcome was 2-year local failure. We compared overall survival (OS), disease-free survival (DFS), hospitalizations, and toxicity.

RESULTS

There were 32 patients in the 3F group and 118 in the LF group, with a median follow up of 22 months. The 3F had worse performance status (p = 0.01) but otherwise similar characteristics. The 2-year local failure rate was 3.6% (95% CI 0%, 10.6%) for 3F, and 7.5% (95% CI 2.4%, 12.6%) for LF. The univariable hazard ratio (HR) for local failure for 3F was 0.43 (0.05, 3.43; p = 0.43). Moreover, 2 of 32 (6.3%) 3F patients experienced Grade ...3 toxicity compared to 7 of 118 (5.9%) LF patients (p = 1.0), with no difference in hospitalization within 2 years (p = 0.66) and no treatment-related deaths.

CONCLUSIONS

Local control was excellent, with long term survival and toxicity similar between the groups. These findings support consideration of 3F.

High dose rate192Ir versus high dose rate60Co brachytherapy: an overview of systematic reviews of clinical responses of gynecological cancers from 1984 to 2020

The Purpose. Radioisotope of192Iradium (192Ir) has a half-life (74 days) and is not easily accessible in developing countries. As a result, by the time source shipment clearance and the customs paperwork are completed, a large proportion of useful activity had already been decayed away. In fact,60Cobalt (60Co) remote afterloading systems are commercially available by many venders. As a result, it may well become an alternative source to192Ir and conform many of these challenges. The aim of this study is that to report clinical responses of different types of gynaecological cancers treated with high dose rate (HDR)192Ir and HDR60Co brachytherapy in order to check whether HDR60Co could be used as an alternative brachytherapy, source to HDR192Ir.Materials and Methods. A retrospective study of clinical responses of different types of gynaecological cancers, staged from I to IV according to recommendations of International Federation of Gynaecology and Obstetrics (FIGO), treated by brachytherapy alone, radiotherapy alone (combined brachytherapy and radiotherapy) and combined radiotherapy and chemotherapy (brachytherapy, radiotherapy and chemotherapy) between 1984 and December 2020 was conducted. The patients were treated with external beam radiotherapy 45-51 Gy boosted with HDR192Ir and HDR60Co afterloading brachytherapy of 18-30 Gy to point A.The results. The study scrutinized the data of 11086 patients with different types of gynaecological cancers. Most of the patients, 70 percent of them, were diagnosed with gynaecological cancers in stages II and III. For patients treated with192Ir brachytherapy source 5-years overall survival rate (OS), local control, 2-years, 5-years and 10-years disease free survival (DFS), complications of gastro-intestine (GI) and complications of genito-urinary (GU) were 63.5%, 92%, 72.6%, 64.07%, 43.75%, 3.9% and 5.92%, but for those treated with60Co they were 57.7%, 86.63%, 82.5%, 53.35%, 43.75%, 4.8% and 3.7%, respectively.Conclusions.The use of HDR60Co brachytherapy has the capacity to produce overall survival rate and disease control in patients with carcinoma of the gynaecology comparable to that reported for HDR192Ir brachytherapy. Currently, the toxicity and damage of the normal tissues and radiation-related second cancers are of a similar incidence to that of standard HDR192Ir brachytherapy. Source exchange frequency is not a serious concern because it requires less frequency of replacement, and commissioning can be accomplished within years; hence, replacing HDR192Ir with HDR60Co brachytherapy achieves significant cost saving. Therefore, we recommend that60Co source ought to be the first choice for low resource radiotherapy setting as it offers economic advantages over192Ir and have comparable clinical outcomes to that of192Ir source.

American Brachytherapy Task Group Report: A pooled analysis of clinical outcomes for high-dose-rate brachytherapy for cervical cancer

PURPOSE

Advanced imaging used in combination with brachytherapy (BT) has revolutionized the treatment of patients with cervical cancer. We present a comprehensive review of the literature for definitive radiation with high-dose-rate (HDR) BT. In addition, we investigate potential outcome improvement with image-based brachytherapy (IBBT) compared to studies using traditional Point A dosing. This review extensively investigates acute and late toxicities.

METHODS AND MATERIALS

This study reviews the literature from 2000 to 2015 with an emphasis on modern approaches including concurrent chemotherapy (chemoRT), radiation, and HDR BT and IBBT. Descriptive statistics and pelvic control (PC), disease-free survival (DFS), and overall survival (OS) outcomes were calculated using weighted means to report pooled analysis of outcomes.

RESULTS

Literature search yielded 16 prospective, 51 retrospective studies that reported survival outcomes, and 13 retrospective studies that focused on acute and late toxicity outcomes regardless of applicator type. There are 57 studies that report Point A dose specification with 33 having chemoRT, and 10 studies that use IBBT, 8 with chemoRT. Patients receiving radiation and chemoRT with HDR BT in the prospective studies, with >24 months followup, rates of PC were: for RT: 73%, SD: 11; CRT: 82%, SD: 8; DFS-RT: 55%, SD: 10; CRT: 65%, SD: 7; OS-RT: 66%, SD: 7; CRT: 70%, SD: 11. In the retrospective studies, the PC rates (weighted means) for the radiation and chemoradiation outcomes are 75% vs. 80%, and for DFS, the values were 55% vs. 63%, respectively. Comparing patients receiving chemoRT and IBBT to traditional Point A dose specification, there is a significant improvement in PC (p < 0.01) and DFS (p < 0.01) with IBBT. The range of genitourinary late toxicity reported for radiation was Grade 3: 1-6% and for chemoRT 2-20%. The range of late gastrointestinal toxicity for radiation was Grade 3: 4-11% and for chemoRT, 1-11%. For the late gynecologic toxicity, only 1 of the 16 prospective trials report a Grade 1-2 of 17% for radiation and 9% for chemoRT effects.

CONCLUSIONS

We present concise outcomes of PC, DFS, OS, and toxicity for cervical cancer patients treated with chemoradiation and HDR BT. Our data suggest an improvement in outcomes with the use of IBBT compared with traditional Point A dose prescriptions. In conclusion, HDR BT is a safe, effective modality when combined with IBBT.

A Comparative Analysis of Two Different Dose Fractionation Regimens of High Dose Rate Intracavitary Brachytherapy in Treatment of Carcinoma of Uterine Cervix: A Prospective Randomized Study

INTRODUCTION

High Dose Rate (HDR) intracavitary brachytherapy is an integral component in treatment of carcinoma uterine cervix. There is no consensus about optimal fractionation in HDR brachytherapy.

AIM

To assess the feasibility, tolerability of HDR intracavitary brachytherapy schedule of 8 Gy per fraction per week for 3 fractions over 6Gy per fraction per week for 4 fractions with or without chemotherapy in the treatment of carcinoma of uterine cervix.

MATERIALS AND METHODS

From 2013 to 2014 total 80 patients with carcinoma of the uterine cervix (Stages IIB and IIIB) were treated with External Beam Radiotherapy (EBRT) and High Dose Rate Intracavitary Brachytherapy (HDR- ICBT). During course of EBRT, those patients fit for brachytherapy were randomized to arm A- 6 Gy per fraction per week for 4 fractions and arm B - 8 Gy per fraction per week for 3 fractions.

RESULTS

The median follow up was 30 months, local control was 90% in Arm A and 83.3% in Arm B (p= 0.21) and the disease-free survival was 90% in Arm A and 83.3% in Arm B (p= 0.39). There is no significance difference for late rectal and bladder toxicities between two arms (p=0.43).

CONCLUSION

Taking into account of increased hospital burden of locally advanced cancer cervix patients in Indian context, HDR intracavitary brachytherapy schedule of 8 Gy per fraction per week x 3 fractions is the preferable option over 6 Gy per fraction per week x 4 fractions with regard to comparable loco-regional control, acute and late toxicity, disease free survival and better patients compliance to lesser fractionation schedule.

Impact of treatment time-related factors on prognoses and radiation proctitis after definitive chemoradiotherapy for cervical cancer

This study aimed to investigate the impact of treatment time-related factors on outcomes and radiation proctitis in patients undergoing concurrent chemoradiotherapy (CCRT) for cervical cancer. From September 2001 to December 2012, 146 patients with stage IIB cervical squamous cell carcinoma treated with CCRT were reviewed from a prospective cohort. Patients who received the same dose (45 Gy) of external beam radiation therapy (EBRT) were included in the analysis (n = 125). The same equivalent dose of 2 Gy (EQD2) of high-dose-rate intracavitary brachytherapy (HDR-ICBT) was delivered at either 4 fractions of 6 Gy or 6 fractions of 4.5 Gy. The effects of the overall treatment time (OTT) and interval between EBRT and HDR-ICBT on the cancer-specific survival (CSS), local recurrence (LR), and incidence of proctitis were compared. The treatment time-related factors did not adversely affect the CSS and LR rates. The multivariate analyses did not identify the OTT as an independent factor of CSS (P = 0.839) and LR (P = 0.856). However, OTT ≤56 days (P = 0.026) was identified as the only independent factor of overall proctitis. The 5-year Grade 2 or greater proctitis rates were 14.9% and 0% (P = 0.001) in patients with the EBRT to ICBT interval ≤5 days and >5 days, respectively. To reduce rectal damage without compromising prognosis, the gap between EBRT and HDR-ICBT should exceed 5 days in cervical cancer patients undergoing CCRT. Strictly limiting the OTT to 56 days may result in radiation proctitis without improvements in prognosis.

Late rectal toxicity determined by dose-volume parameters in computed tomography-based brachytherapy for locally advanced cervical cancer

The aim of this study was to observe the relationship between dose–volume histogram (DVH) parameters and rectal late side effects (LSE) in computed tomography (CT)‐based brachytherapy (BT) for patients with locally advanced cervical cancer. In total, 144 cervical cancer patients received external beam radiotherapy and CT‐based BT. The data from 111 survival cases with pelvic local control (LC) were used to analyze the relationship between DVH parameters and rectal LSE. The total doses, manifesting 2, 1, and 0.1 cm³ (D_2cc, D_1cc, and D_0.1cc) of the rectum, and D₉₀ for high‐risk clinical target volume (HR CTV) were computed and normalized to 2 Gy fractions (EQD2) using a linear‐quadratic model. The rectal LSE were evaluated by the late effects in normal tissues‐subjective, objective, management, and analytic (LENT‐SOMA) scale. A dose–response relationship was evaluated by probit analyses. For all patients, the total rate of rectal LSE was 56%, and the rate of ≥Grade 2 LSE was 27.4%. For the 111 survival cases with pelvic LC, the total mean for D_2cc was 71.23 ± 5.54 Gy for the rectum, and the D_2cc, D_1cc, and D_0.1cc values for Grades 2 and 3 were higher than those for Grades 0 and 1. In addition, the number of complications increased, and the complications became more severe as the dose increased, with a dose of 73.5 Gy resulting in a 10% probability of ≥Grade 3 LSE. In conclusion, DVH parameters could predict the incidence and grades of rectal LSE in CT‐based BT. D_2cc showed an excellent predictive value, and 73.5 Gy for D_2cc of the rectum might be considered as an alternative dose limit.

Brachytherapy in the treatment of cervical cancer: a review

Dramatic advances have been made in brachytherapy for cervical cancer. Radiation treatment planning has evolved from two-dimensional to three-dimensional, incorporating magnetic resonance imaging and/or computed tomography into the treatment paradigm. This allows for better delineation and coverage of the tumor, as well as improved avoidance of surrounding organs. Consequently, advanced brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with historic approaches. This review provides an overview of state-of-the-art gynecologic brachytherapy, with a focus on recent advances and their implications for women with cervical cancer.

Endoscope-guided interstitial intensity-modulated brachytherapy and intracavitary brachytherapy as boost radiation for primary early T stage nasopharyngeal carcinoma

BACKGROUND

Intracavitary brachytherapy (ICBT) is usually applied as boost radiotherapy for superficial residual of nasopharyngeal carcinoma (NPC) after primary extern-beam radiptherapy (ERT). Here, we evaluated the outcome of endoscope-guided interstitial intensity-modulated brachytherapy (IMBT) boost radiation for deep-seated residual NPC.

METHODOLOGY/PRINCIPAL FINDINGS

Two hundred and thirteen patients with residual NPC who were salvaged with brachytherapy boost radiation during 2005-2009 were analyzed retrospectively. Among these patients, 171 patients had superficial residual NPC (≤1 cm below the nasopharyngeal epithelium) were treated with ICBT boost radiation, and interstitial IMBT boost radiation was delivered to 42 patients with deep-seated residual NPC (>1 cm below the nasopharyngeal epithelium). We found that IMBT boost subgroup had a higher ratio of T2b (81.0% VS 34.5%, P<0.001) and stage II (90.5% VS 61.4%, P = 0.001) than that of ICBT boost subgroup. The dosage of external-beam radiotherapy in the nasopharyngeal (63.0±3.8 VS 62.6±4.3 Gray (Gy), P = 0.67) and regional lymph nodes (55.8±5.0 VS 57.5±5.7 Gy, P = 0.11) was comparable in both groups. For brachytherapy, IMBT subgroup had a lower boost radiation dosage than ICBT subgroup (11.0±2.9 VS 14.8±3.2 Gy, P<0.01). Though the IMBT group had deeper residual tumors and received lower boost radiation dosages, both subgroups had the similar 5-year actuarial overall survival rate (IMBT VS ICBT group: 96.8% VS 93.6%, P = 0.87), progression-free survival rate (92.4% VS 86.5%, P = 0.41) and distant metastasis-free survival rate (94.9% VS 92.7%, P = 0.64). Moreover, IMBT boost radiation subgroup had a similar local (97.4% VS 94.4%, P = 0.57) and regional (95.0% VS 97.2%, P = 0.34) control to ICBT subgroup. The acute and late toxicities rates were comparable between the both subgroups.

CONCLUSIONS/SIGNIFICANCE

IMBT boost radiation may be a promising therapeutic selection for deep-seated residual NPC.