HYPOfractionated RadioTherapy in Cervical Cancer

This study is a prospective, parallel-group, randomized, interventional, non-inferiority clinical trial evaluating definitive hypofractionated external beam radiotherapy in comparison with conventional fractionated external beam radiotherapy for women with locally advanced carcinoma of the cervix treated with concurrent cisplatin-based chemoradiation and image-guided brachytherapy. The protocol is designed to test whether reduction of external beam treatment duration through a moderate hypofractionated schedule can maintain pelvic loco-regional control within a prespecified non-inferiority margin while potentially improving feasibility, throughput, and patient adherence in a high-burden practice environment.

The background for the study is rooted in the persistent gap between disease burden and radiotherapy access in cervical cancer. In many low-resource and high-volume centers, a standard course of pelvic chemoradiation followed by brachytherapy requires multiple weeks of daily attendance and often imposes logistical, geographic, and financial burdens on patients. Treatment prolongation and interruptions are clinically important because Overall Treatment Time(OTT) has long been recognized as a determinant of disease control in cervical cancer, and delays may adversely affect local control through accelerated tumor repopulation. A shortened external beam component may therefore provide both operational and biologic advantages if tumor dose, normal tissue constraints, and brachytherapy integration are carefully preserved.

Hypofractionation in gynecologic malignancies has historically been approached cautiously because of concerns related to bowel, bladder, rectal, vaginal, and other pelvic normal tissue tolerance. However, advances in treatment planning and delivery, including three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, volumetric planning, image guidance, and standardized brachytherapy contouring, have increased the feasibility of testing moderate hypofractionated schedules with modern organ-at-risk protection. Available early and phase I/II experience suggests that moderately hypofractionated pelvic radiotherapy may be deliverable with acceptable acute toxicity in selected cervical cancer settings, but large randomized datasets remain limited. This trial is designed to address that evidence gap by generating comparative data in a prospective randomized framework.

The study population comprises women with histopathologically confirmed locally advanced cervical cancer considered suitable for definitive chemoradiation. Participants are expected to have disease stages appropriate for radical treatment, adequate hematologic, renal, and hepatic function to receive concurrent cisplatin, and performance status compatible with curative-intent therapy. Patients with advanced metastatic disease, prior pelvic radiotherapy, prior systemic therapy that would confound response assessment, uncontrolled comorbidity, pregnancy, or other protocol-specified exclusions would not be eligible. Final eligibility, staging workup, and protocol-specific inclusion and exclusion criteria are addressed in the corresponding sections of the registry and protocol document.

After confirmation of eligibility and baseline evaluation, participants will be randomized in a 1:1 allocation ratio to standard fractionation or hypofractionation. Randomization is intended to reduce allocation bias and permit an unbiased estimate of comparative treatment effect across efficacy and safety endpoints. Stratification factors may include clinically relevant prognostic variables such as nodal status or other institutional balancing factors, as prespecified in the protocol and statistical analysis plan.

The control arm consists of definitive external beam radiotherapy delivered to the pelvis using conventional fractionation, administered concurrently with weekly cisplatin chemotherapy, followed by brachytherapy. The experimental arm consists of definitive hypofractionated External Beam Radiotherapy (EBRT) delivered over a shorter period, also with concurrent weekly cisplatin and subsequent brachytherapy. The intent of the experimental intervention is not dose escalation but schedule compression, with maintenance of curative treatment intensity through altered fraction size and appropriate radiobiologic design. Radiotherapy planning, target volume delineation, nodal coverage, boost policy where indicated, and organ-at-risk dose limitation are expected to follow protocol-defined institutional standards consistent with modern image-guided treatment delivery.

The rationale for concurrent chemotherapy in both arms is to preserve the accepted standard of radiosensitization in definitive management of locally advanced cervical cancer. Cisplatin-based concurrent chemoradiation remains the standard backbone of therapy for appropriately selected patients and is therefore retained in both treatment groups to ensure that the comparison isolates the effect of fractionation schedule rather than omitting a key therapeutic component. Similarly, brachytherapy is included in both study arms because it is an essential component of definitive cervical cancer treatment and is necessary for optimal local control.

The primary endpoint is loco-regional pelvic control, assessed according to protocol-defined clinical and imaging criteria at prespecified follow-up time points. Non-inferiority testing is structured to determine whether the hypofractionated approach preserves disease control within an acceptable predefined margin compared with the conventional schedule. Selection of a non-inferiority design is appropriate because the anticipated benefit of the investigational approach is not necessarily superior tumor response, but comparable efficacy with reduced treatment duration, improved convenience, and potentially improved system efficiency.

Secondary endpoints include acute toxicity, late toxicity, disease-free survival, overall survival, and patient-reported quality of life. Toxicity assessment is expected to use standardized grading systems and serial clinical review during treatment and follow-up. Acute adverse effects of interest include gastrointestinal, genitourinary, hematologic, dermatologic, and treatment-compliance events, whereas late effects may include bowel, bladder, vaginal, pelvic soft-tissue, and other radiation-related morbidity identified during longitudinal follow-up. Patient-reported outcomes are of particular importance because hypofractionation, if effective, may confer meaningful reductions in treatment burden even when classical oncologic outcomes appear similar. The baseline evaluation is expected to include detailed clinical examination, histopathologic confirmation, standard laboratory testing, and staging investigations appropriate for locally advanced cervical cancer. Imaging-based assessment before treatment is important for stage assignment, nodal evaluation, and radiotherapy planning. During active treatment, participants will undergo routine clinical review, toxicity monitoring, and laboratory assessment as required for cisplatin-based chemoradiation. After completion of treatment, follow-up visits will evaluate response, disease status, toxicity, and quality-of-life measures according to the study schedule.

The operational significance of this study is substantial. In high-volume departments, a reduction in the number of external beam fractions per patient may improve linear accelerator availability, reduce waiting time, and facilitate timely treatment for a larger number of patients. For patients, a shorter external beam schedule may decrease indirect cost, travel burden, family disruption, and the risk of default associated with prolonged daily attendance. These potential advantages are especially relevant in emerging countries where radiotherapy demand often exceeds available capacity.

The trial also has scientific importance because it may help define whether moderate hypofractionation can be integrated safely into definitive cervical cancer management when brachytherapy and concurrent chemotherapy are preserved. Positive results would support a clinically meaningful change in practice by establishing evidence for a shorter schedule that remains consistent with modern curative treatment principles. Negative or inconclusive results would still be valuable because they would clarify the limits of schedule compression in this disease and inform future protocol refinement.

From a methodological perspective, the study emphasizes comparability of multimodality care except for the external beam fractionation schedule, thereby strengthening interpretability of the comparison. Because both arms receive definitive treatment with chemotherapy and brachytherapy, any observed differences in disease control, toxicity, or quality of life can be more plausibly attributed to the external beam treatment schedule and its interaction with overall treatment time. This design is aligned with the practical clinical question faced by cancer centers: whether a shorter pelvic radiotherapy course can substitute for the standard schedule without unacceptable loss of efficacy. The anticipated implications of the study extend beyond a single institution. If the hypofractionated regimen is shown to be non-inferior and operationally advantageous, the findings may be applicable to oncology services in other regions confronting similar constraints in machine time, patient access, and treatment completion.

The study therefore has relevance not only as a clinical efficacy trial, but also as a health-service optimization strategy in settings with a high cervical cancer burden.