Breast cancer (BC) is the most commonly diagnosed type of cancer and the leading cause of cancer deaths in women. Smoking is the principal modifiable risk factor for cancers and has a negative influence on long-term survival. We conducted a retrospective study on consecutive BC survivors seen at follow-up consultations between 3 June and 30 October 2019 at Institut Curie, Paris, France. Smoking behaviors were evaluated prospectively via interviewer-administered questionnaires. The aim of this study was to describe smoking-related patient care at diagnosis and smoking cessation patterns in women with a history of BC. A total of 1234 patients were included in the study. Smoking status at diagnosis was missing from electronic health records in 32% of cases, including 13% of patients who smoke. Only 20% of the 197 patients currently smoking at diagnosis recalled having a discussion about smoking with a healthcare professional. Radiotherapists and surgeons were more likely to talk about complications than other practitioners. The main type of information provided was general advice to stop smoking (n = 110), followed by treatment complications (n = 48), while only five patients were referred to tobaccologists. Since diagnosis, 33% (n = 65) of the patients currently smoking had quit. Patients who quit had a lower alcohol consumption, but no other factor was associated with smoking cessation. The main motivation for tobacco withdrawal was the fear of BC relapse (63%). This study highlights room for improvement in the assessment of smoking behavior. Our data raise important perspectives for considering BC treatment and follow-up as a window of opportunity for smoking cessation.

Tobacco use is associated with an increase in breast cancer (BC) mortality. Pathologic complete response (pCR) rate to neoadjuvant chemotherapy (NAC) is influenced by tumor-infiltrating lymphocyte (TIL) levels and is associated with a better long-term survival outcome. The aim of our study is to evaluate the impact of smoking status on TIL levels, response to NAC and prognosis for BC patients. We retrospectively evaluated pre- and post-NAC stromal and intra tumoral TIL levels and pCR rates on a cohort of T1-T3NxM0 BC patients treated with NAC between 2002 and 2012 at Institut Curie. Smoking status (current, ever, never smokers) was collected in clinical records. We analyzed the association between smoking status, TIL levels, pCR rates and survival outcomes among the whole population, and according to BC subtype. Nine hundred and fifty-six BC patients with available smoking status information were included in our analysis (current smokers, n = 179 (18.7%); ever smokers, n = 154 (16.1%) and never smokers, n = 623 (65.2%)). Median pre-NAC TIL levels, pCR rates, or median post-NAC TIL levels were not significantly different according to smoking status, neither in the whole population, nor in any BC subtype group. With a median follow-up of 101.4 months, relapse-free survival (RFS) and overall survival (OS) were not significantly different by smoking status. We did not find any significant effect of tobacco use on pre- and post-NAC TILs nor response to NAC. Though our data seem reassuring, BC treatment should still be considered as a window of opportunity to offer BC patients accurate smoking cessation interventions.

No abstract

Tobacco use is associated with an increase in breast cancer (BC) mortality. Pathologic complete response rate to neoadjuvant chemotherapy (NAC) is influenced by tumor-infiltrating lymphocytes (TILs) levels and is associated with a better long-term survival outcome. Whether tobacco modifies either tumoral microenvironment such as TIL levels, either pCR rates remains unclear. The aim of our study is to evaluate the impact of smoking status on TIL levels, response to NAC and prognosis for BC patients. We retrospectively evaluated pre and post NAC stromal and intra tumoral TIL levels and pCR rates on a cohort of T1-T3NxM0 BC patients treated with NAC between 2002 and 2012 at Institut Curie. Smoking status (current, ever, never smokers) was collected in clinical records. We analyzed the association between smoking status, TIL levels, pCR rates and survival outcomes among the whole population, and after stratification by BC subtype. A total of 956 BC patients with available smoking status information were included in our analysis [current smokers, n=179 (18.7%); ever smokers, n=154 (16.1%) and never smokers, n=623 (65.2%)]. Median pre-NAC TIL levels, pCR rates, or median post-NAC TIL levels were not significantly different according to smoking status, neither in the whole population, nor after stratification by BC subtype. With a median follow-up of 101.4 months, relapse free survival (RFS) and overall survival (OS) were not significantly different by smoking status. In this study, we did not find any significant effect of tobacco use on pre and post NAC TILs nor response to NAC and. Though are data seem reassuring, BC treatment should still be considered as a window of opportunity to offer BC patients accurate smoking cessation interventions.