Abstract P6-12-18: CANTOCHEM: Analysis of chemotherapy practice and early side effects in the 6090 first patients from the prospective CANTO cohort
Authors: Cottu PH , Amar Y , Pistilli B , Bonsang-Kitzis H , Lesur A , Lerebours F , Vanlemmens L , Tredan O , Levy C , Jouannaud C , Fournier M , Soulie P , Rigal O , Giacchetti S , Arnaud A , Arsene O , Savignoni A , Mesleard C , Andre F , Arveux P 
Published: February 2018

Abstract
Background
There is no large prospective trial assessing mid-term adverse effects of adjuvant chemotherapy. In order to address this question, we developed CANTO (CANcer TOxicities - NCT01993498 - http://etudecanto.org/), a prospective trial dedicated to the quantification of side effects after treatment for patients with early breast cancer and to develop predictors of such toxicities. The aim of this presentation is to assess chemotherapy (CT) practice and to report toxicities that persist 3-6 months after CT.
Methods
CANTO is a prospective study enrolling newly diagnosed invasive cT0-cT3, cN0-3, M0 breast cancer patients (pts) of 26 French comprehensive cancer centers. The study has included 10 500 patients at the time of submission. Pts are assessed at diagnosis, 3-6, 12, 36, 48 and 60 months after treatment completion. CANTO collects &gt;100 items related to toxicities. In the current study, we focus on the first set of data available from the trial (1st database lock, n=6090). We here assess CT practice and toxicities at 3 months.
Results
Information about (neo)adjuvant CT (NACT/ACT) is available in 5805 pts (96%). Median age at diagnosis was 57y (22-93). Pts had HR+/HER2-, HER2+ or triple negative (TN) tumors in 74%, 15% and 11% of cases. Ki67 was assessed in 70%, and genomic tests in 1% of pts, respectively.
Overall, 3074 pts (53%) received CT, either adjuvant (ACT: 76%) or neoadjuvant (NACT: 24%). ACT/NACT pts (84%) received a sequential anthracyclines–taxanes based 6 courses CT schedule. CT was administered in 44.7%, 87.2% and 92.3% of HR+/HER2+/TN tumors, respectively. ACT was administered in 73.2% of pT2+ pts (vs 36.0% in pT0-1 – p&lt;.001)) and in 74.7% in pN1+pts (vs 36.7% in pN0 – p&lt;.001)). After NACT, pts had yPT0 (32.3%) and/or ypN0 (64.6%) for an overall 28.9% pCR rate.
We focus here on clinically most relevant patient reported symptoms at 3 m (any grade).
side effects at 3m no CT (%)CT (%)p valuePain76.682.1&lt;.001Neurological symptom4768.7&lt;.001GI symptom34.342.1&lt;.001CV sympton8.110.20.011
Pain complaint was recorded in 3596 pts (97.2% of pts with available data), with a median value of 4 on the VAS (range 1-10). In ACT/NACT pts, muscle and joint pain were predominant. Neurological symptoms were seen in 3024 pts (59%), the most frequent pertaining to cognitive disorder (attention trouble, CT: 61.2% vs noCT: 56% - p=.06) and peripheral neuropathy (overall 31%). Paresthesias and sensory neuropathy were much more frequent in CT vs noCT pts: respectively 37.3% vs 20.3% and 25.7% vs 12.8% (both p&lt;.001). Of note, pts receiving paclitaxel had more peripheral neuropathy (92.3% vs 69% in docetaxel pts – p=.07). Diarrhea was the most frequent GI symptom post CT: 44.5% vs 33.2%, p&lt; 0.001. CV symptoms (NOS) were slightly more frequent after CT.
Conclusions
In this real life, prospective cohort, CT is frequently prescribed and appears in good compliance with current guidelines. Overall, symptoms burden at treatment completion is strikingly high, and much higher in pts receiving CT. A special attention should be given to pain and neurological symptoms. Dedicated questionnaires and sub-studies will explore in depth these side effects. Extended analyses of CT practice and toxicities will be presented.
Citation Format: Cottu PH, Amar Y, Pistilli B, Bonsang-Kitzis H, Lesur A, Lerebours F, Vanlemmens L, Tredan O, Levy C, Jouannaud C, Fournier M, Soulie P, Rigal O, Giacchetti S, Arnaud A, Arsene O, Savignoni A, Mesleard C, Andre F, Arveux P. CANTOCHEM: Analysis of chemotherapy practice and early side effects in the 6090 first patients from the prospective CANTO cohort [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-18.