CANTO-RT: One of the Largest Prospective Multicenter Cohort of Early Breast Cancer Patients Treated with Radiotherapy including Full DICOM RT Data

Abstract

This article describes the methodology used and provides a characterization of the study population in CANTO-RT (CANcer TOxicities RadioTherapy). CANTO (NCT01993498) is a prospective clinical cohort study including patients with stage I-III BC from 26 French cancer centers. Patients matching all CANTO inclusion and exclusion criteria who received RT in one of the 10 top recruiting CANTO centers were selected. Individual full DICOM RT files were collected, pseudo-anonymized, structured and analyzed on the CANTO-RT/UNITRAD web platform. CANTO-RT included 3875 BC patients with a median follow-up of 64 months. Among the 3797 patients with unilateral RT, 3065 (80.4%) had breast-conserving surgery, and 2712 (71.5%) had sentinel node surgery. Tumor bed boost was delivered in 2658 patients (68.5%) and lymph node RT in 1356 patients (35%), including internal mammary chain in 844 patients (21.8%). Most patients (3691 (95.3%)) were treated with 3D conformal RT. Target volumes, organs at risk contours and dose/volume histograms were extracted after quality-control procedures. CANTO-RT is one of the largest early BC prospective cohorts with full individual clinical, biological, imaging and DICOM RT data available. It is a valuable resource for the identification and validation of clinical and dosimetric predictive factors of RT and multimodal treatment-related toxicities.

End-to-end framework for automated collection of large multicentre radiotherapy datasets demonstrated in a Danish Breast Cancer Group cohort

“…Despite the missing data, we were able to collect a dataset that is among the largest in radiotherapy containing full DICOM data. In comparison, the recently published CANTO-RT study from France included 3976 breast cancer patients [6] .…”

“…This need can be met by prospective data collection in clinical studies; however, it can be very time consuming for large datasets [6] . A multicentre collaborative effort to implement local methods for bulk DICOM data extraction would make this process faster and enable learning from archived treatment data, but may also increase the need for data curation, as data is not assessed on an individual level.…”

Radiation-induced lung injury after breast cancer treatment: incidence in the CANTO-RT cohort and associated clinical and dosimetric risk factors

“…The CANTO RT cohort provides a unique opportunity to assess long-term outcomes and toxicities of breast cancer RT over time ( 15 ). CANTO-RT is a subset of CANTO (NCT01993498) a prospective longitudinal multicentric cohort that enables clinical and dosimetric risk factor assessment for long term RT toxicities ( 16 , 17 ).…”

CANTO skin: Evaluation of skin toxicity risk factors in patients treated for breast cancer

“…In fact, the identification of risk factors 15‐17 for the appearance of skin toxicities represents a major challenge in the treatment of patients in order to anticipate them and, to manage them in a personalised approach. Through the various CANTO studies, we are attempting to identify numerous factors influencing the occurrence of toxicity, such as fatigue 18 or cardiac toxicity 19 . With the help of a vast database reported prospectively in several major French centres, we have been able to analyse a large sample of patients and a vast number of factors, whether intra‐ or interindividual, related to treatment or tumour characteristics.…”

“…Through the various CANTO studies, we are attempting to identify numerous factors influencing the occurrence of toxicity, such as fatigue 18 or cardiac toxicity. 19 With the help of a vast database reported prospectively in several major French centres, we have been…”