PURPOSE: To test effects of positron emission tomography (PET)-based bone marrow-sparing (BMS) image-guided intensity modulated radiation therapy (IG-IMRT) on efficacy and toxicity for patients with locoregionally advanced cervical cancer. METHODS AND MATERIALS: In an international phase II/III trial, patients with stage IB-IVA cervical carcinoma were treated with either PET-based BMS-IG-IMRT (PET-BMS-IMRT group) or standard image-guided IMRT (IMRT group), with concurrent cisplatin (40 mg/m2 weekly), followed by brachytherapy. The phase II component nonrandomly assigned patients to PET-BMS-IMRT or standard IMRT. The phase III trial randomized patients to PET-BMS-IMRT versus IMRT, with a primary endpoint of progression-free survival (PFS) but was closed early for futility. Phase III patients were analyzed separately and in combination with phase II patients, comparing acute hematologic toxicity, cisplatin delivery, PFS, overall survival (OS), and patterns of failure. In a post-hoc exploratory analysis, we investigated the association between pretreatment absolute lymphocyte count (ALC) and OS. RESULTS: In total, 101 patients were enrolled on the phase II/III trial, including 29 enrolled in phase III (PET-BMS-IMRT group: 16; IMRT group: 13) before early closure. Median follow-up was 33 months for phase III patients and 39 months for all patients. PFS and OS at 5 years for all patients were 73.6% (95% confidence interval [CI], 64.9%-84.3%) and 84% (95% CI, 76%-92.9%]), respectively. There were no differences in number of cisplatin cycles, OS, PFS, or patterns of failure between groups for the combined cohort. The incidence of acute grade ≥ 3 neutropenia was significantly lower in the PET-BMS-IMRT group compared with IMRT for randomized patients (19% vs 54%, χ2P = .048) and in the combined cohort (13% vs 35%, χ2P = .01). Patients with pretreatment ALC ≤ 1.5 k/μL had nonsignificantly worse OS on multivariable analysis (HR 2.85; 95% CI, 0.94-8.62; adjusted P = .216), compared with patients with ALC > 1.5 k/μL. There was no difference in posttreatment ALC by treatment group. CONCLUSIONS: PET-BMS-IMRT significantly reduced acute grade ≥3 neutropenia, but not treatment-related lymphopenia, compared with standard IMRT. We found no evidence that PET-BMS-IMRT affected chemotherapy delivery or long-term outcomes, and weak evidence of an association between pretreatment ALC and OS.
- MeSH
- cisplatina terapeutické užití MeSH
- kostní dřeň účinky záření MeSH
- lidé MeSH
- nádory děložního čípku * diagnostické zobrazování farmakoterapie patologie radioterapie MeSH
- pozitronová emisní tomografie MeSH
- radioterapie řízená obrazem MeSH
- radioterapie s modulovanou intenzitou * škodlivé účinky metody MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky, fáze II MeSH
- klinické zkoušky, fáze III MeSH
- randomizované kontrolované studie MeSH
- Research Support, N.I.H., Extramural MeSH
PURPOSE: To demonstrate an efficient method for training and validation of a knowledge-based planning (KBP) system as a radiation therapy clinical trial plan quality-control system. METHODS AND MATERIALS: We analyzed 86 patients with stage IB through IVA cervical cancer treated with intensity modulated radiation therapy at 2 institutions according to the standards of the INTERTECC (International Evaluation of Radiotherapy Technology Effectiveness in Cervical Cancer, National Clinical Trials Network identifier: 01554397) protocol. The protocol used a planning target volume and 2 primary organs at risk: pelvic bone marrow (PBM) and bowel. Secondary organs at risk were rectum and bladder. Initial unfiltered dose-volume histogram (DVH) estimation models were trained using all 86 plans. Refined training sets were created by removing sub-optimal plans from the unfiltered sample, and DVH estimation models… and DVH estimation models were constructed by identifying 30 of 86 plans emphasizing PBM sparing (comparing protocol-specified dosimetric cutpoints V10 (percentage volume of PBM receiving at least 10 Gy dose) and V20 (percentage volume of PBM receiving at least 20 Gy dose) with unfiltered predictions) and another 30 of 86 plans emphasizing bowel sparing (comparing V40 (absolute volume of bowel receiving at least 40 Gy dose) and V45 (absolute volume of bowel receiving at least 45 Gy dose), 9 in common with the PBM set). To obtain deliverable KBP plans, refined models must inform patient-specific optimization objectives and/or priorities (an auto-planning "routine"). Four candidate routines emphasizing different tradeoffs were composed, and a script was developed to automatically re-plan multiple patients with each routine. After selection of the routine that best met protocol objectives in the 51-patient training sample (KBPFINAL), protocol-specific DVH metrics and normal tissue complication probability were compared for original versus KBPFINAL plans across the 35-patient validation set. Paired t tests were used to test differences between planning sets. RESULTS: KBPFINAL plans outperformed manual planning across the validation set in all protocol-specific DVH cutpoints. The mean normal tissue complication probability for gastrointestinal toxicity was lower for KBPFINAL versus validation-set plans (48.7% vs 53.8%, P<.001). Similarly, the estimated mean white blood cell count nadir was higher (2.77 vs 2.49 k/mL, P<.001) with KBPFINAL plans, indicating lowered probability of hematologic toxicity. CONCLUSIONS: This work demonstrates that a KBP system can be efficiently trained and refined for use in radiation therapy clinical trials with minimal effort. This patient-specific plan quality control resulted in improvements on protocol-specific dosimetric endpoints.
- MeSH
- klinické zkoušky jako téma normy MeSH
- kostní dřeň MeSH
- kritické orgány * MeSH
- léčba šetřící orgány metody normy MeSH
- lidé MeSH
- močový měchýř MeSH
- nádory děložního čípku patologie radioterapie MeSH
- pánevní kosti MeSH
- plánování radioterapie pomocí počítače metody normy MeSH
- radioterapie s modulovanou intenzitou metody normy MeSH
- rektum MeSH
- řízení kvality * MeSH
- střeva MeSH
- tumor burden MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- validační studie MeSH
