INTERLACE Trial Patient Distribution
Enrollment and Demographics
The INTERLACE trial enrolled 500 eligible patients between November 8,2012, and November 17,2022, randomly assigned 1:1 to either standard chemoradiotherapy alone (n=250) or induction chemotherapy followed by chemoradiotherapy (n=250). 1
Age Range
The trial enrolled adults aged ≥18 years, with patients in the INTERLACE trial being notably younger than those in other contemporary cervical cancer studies. 1, 2
FIGO Stage Distribution
The stage distribution was heavily weighted toward earlier locally advanced disease:
- Stage IIB: 354 patients (70%) - representing the majority of enrolled patients 1
- Stage IIIB: 56 patients (11%) 1
- Stage IB1 with nodal involvement, IB2, IIA, and IVA: 90 patients (18%) - comprising the remaining distribution 1
This distribution reflects less advanced disease compared to other trials, as patients with para-aortic lymph node involvement were specifically excluded from enrollment. 2
Nodal Status
Pelvic lymph nodes were positive in 215 patients (43%) of the total cohort. 1 The trial stratified patients by nodal status at randomization, distinguishing between node-positive and node-negative disease. 1
Histology
The trial included patients with:
- Squamous cell carcinoma
- Adenocarcinoma
- Adenosquamous carcinoma 1
Histology (squamous versus non-squamous) was used as a stratification factor at randomization. 1
Treatment Arms
Induction Chemotherapy + Chemoradiotherapy Arm (n=250):
- Induction phase: Weekly intravenous carboplatin (AUC 2) and paclitaxel (80 mg/m²) for 6 weeks 1
- 230 patients (92%) received at least 5 cycles of induction chemotherapy 1
- Median interval between induction and chemoradiotherapy: 7 days 1
- Followed by standard chemoradiotherapy: Weekly cisplatin 40 mg/m² IV for 5 weeks with external beam radiotherapy (45.0-50.4 Gy in 20-28 fractions) plus brachytherapy (minimum total EQD2 of 78-86 Gy) 1
- 212 patients (85%) received 4 or more cycles of cisplatin 1
Chemoradiotherapy Alone Arm (n=250):
- Standard cisplatin-based chemoradiotherapy: Weekly cisplatin 40 mg/m² IV for 5 weeks with external beam radiotherapy (45.0-50.4 Gy in 20-28 fractions) plus brachytherapy (minimum total EQD2 of 78-86 Gy) 1
- 224 patients (90%) received 4 or more cycles of cisplatin 1
Radiotherapy Completion
462 patients (92%) received both external beam radiotherapy and brachytherapy, with a median overall treatment time of 45 days. 1 Patients were stratified by planned external beam radiotherapy type (IMRT/VMAT versus non-IMRT/non-VMAT) and planned total radiotherapy dose (<70 Gy versus ≥70 Gy EQD2). 1
Geographic Distribution
The trial was conducted at 32 medical centers across five countries: Brazil, India, Italy, Mexico, and the United Kingdom. 1