Effect of Wearing a Face Mask on Hand-to-Face Contact by Children in a Simulated School Environment: The Back-to-School COVID-19 Simulation Randomized Clinical Trial

IMPORTANCE

Wearing a face mask in school can reduce SARS-CoV-2 transmission but it may also lead to increased hand-to-face contact, which in turn could increase infection risk through self-inoculation.

OBJECTIVE

To evaluate the effect of wearing a face mask on hand-to-face contact by children while at school.

DESIGN, SETTING, AND PARTICIPANTS

This prospective randomized clinical trial randomized students from junior kindergarten to grade 12 at 2 schools in Toronto, Ontario, Canada, during August 2020 in a 1:1 ratio to either a mask or control class during a 2-day school simulation. Classes were video recorded from 4 angles to accurately capture outcomes.

INTERVENTIONS

Participants in the mask arm were instructed to bring their own mask and wear it at all times. Students assigned to control classes were not required to mask at any time (grade 4 and lower) or in the classroom where physical distancing could be maintained (grade 5 and up).

MAIN OUTCOMES AND MEASURES

The primary outcome was the number of hand-to-face contacts per student per hour on day 2 of the simulation. Secondary outcomes included hand-to-mucosa contacts and hand-to-nonmucosa contacts. A mixed Poisson regression model was used to derive rate ratios (RRs), adjusted for age and sex with a random intercept for class with bootstrapped 95% CIs.

RESULTS

A total of 174 students underwent randomization and 171 students (mask group, 50.6% male; control group, 52.4% male) attended school on day 2. The rate of hand-to-face contacts did not differ significantly between the mask and the control groups (88.2 vs 88.7 events per student per hour; RR, 1.00; 95% CI, 0.78-1.28; P = >.99). When compared with the control group, the rate of hand-to-mucosa contacts was significantly lower in the mask group (RR, 0.12; 95% CI, 0.07-0.21), while the rate of hand-to-nonmucosa contacts was higher (RR, 1.40; 95% CI, 1.08-1.82).

CONCLUSIONS AND RELEVANCE

In this clinical trial of simulated school attendance, hand-to-face contacts did not differ among students required to wear face masks vs students not required to wear face masks; however, hand-to-mucosa contracts were lower in the face mask group. This suggests that mask wearing is unlikely to increase infection risk through self-inoculation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04531254.

Abstract P2-11-08: Impact of COVID-19 on patients undergoing neoadjuvant therapy: A pre/post pandemic analysis and assessment of quality of care delivered

Background: When the first wave of COVID-19 hit globally in early 2020, concerns were raised about access to surgical interventions for cancer patients. It was considered that neoadjuvant therapy (NAT) although conventionally given to locally advanced breast cancer may need to also be provided to earlier-stage disease. In addition, due to the temporary closure of breast cancer screening programs during the pandemic, concerns were raised about patients presenting with later-stage disease at initial diagnosis. This project aims to assess the impact of COVID-19 on the volume of neoadjuvant referrals at a large cancer centre, as well as any stage migration, impact on treatment timelines and impact on outcomes for breast cancer patients compared to the pre-pandemic population. Methods: The BC Cancer Vancouver centre has a neoadjuvant breast cancer program to ensure high quality of care is maintained. This program’s prospective database of breast cancer patients referred for and treated with NAT between the years 2012-2021 was queried to assess data on neoadjuvant referrals, clinical stage, receptor status, treatment timelines, and outcomes between January 1, 2019 - December 31, 2020. Data from the years 2019 and 2020 were compared to evaluate the impact of COVID-19 on NAT. Summary data available from earlier years were also utilized as reference. Results: The COVID-19 pandemic resulted in a 51% increase in the number of patients referred to the neoadjuvant program, with 102 patients referred for NAT in 2019, whereas 154 patients were referred in 2020. This proportional increase in referrals is higher than any other year since the database inception. Of note, during 2020 there were no COVID related closures for cancer surgeries in the province. The proportion of patients referred who received NAT remained similar between 2019 and 2020 (69.1% vs 70.8% in 2020). The trend in referrals by month varied between the two years. In 2019, the majority of patients were referred between April to July with the lowest proportion of referrals in October to December. In 2020, the opposite occurred with the lowest proportion of referrals transpiring between January - June, and the greatest proportion in October to December. The proportion of patients who presented with de-novo metastatic disease was consistent between the two years (7.8% in 2019 vs 9.7% in 2020). Despite the closure of all screening mammography programs between March-June of 2020, the clinical stage and receptor status are equivalent between 2019 and 2020. With regards to treatment timelines, there was a 3 day increase in the median time between referral date and medical oncology consultation in 2020 compared to 2019. No other treatment timeline delays were found between 2019 and 2020. With regards to outcomes, 34.9% of patients achieved pCR in 2019, but only 24.1% achieved pCR in 2020, despite similar stage and receptor subtypes. Conclusion: During the COVID-19 pandemic in 2020, a higher volume of patients were referred for NAT than had ever before been referred, despite the fact that there were no closures of operating rooms in our province for COVID-19. From a quality of care perspective there was a delay in referral to consultation for medical oncology, but no delay on referral to treatment, treatment to surgery, or surgery to radiation. However, and a significantly lower pCR rates was seen in 2020 compared to 2019. The 10% decrease in pCR rates may have resulted from increased complexity in breast cancer cases. This trend may continue, as the impact of COVID-19 on breast cancer outcomes will likely take many years to fully appreciate. Attention should be paid to encouraging women to return to regular breast screening programs to decrease the number of patients needing neoadjuvant therapy.

Citation Format: Lauren Corke, Omar Hajjaj, Kaylie Willemsma, Stephen Chia, Christine Simmons. Impact of COVID-19 on patients undergoing neoadjuvant therapy: A pre/post pandemic analysis and assessment of quality of care delivered [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-11-08.

Comparison of treatment effect and long-term outcomes for pediatric and adult Ewing sarcoma patients in British Columbia, Canada

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Background: Treatment of Ewing Sarcoma (EWS) is challenging. While it is known to be sensitive to chemotherapy and radiation, the number of lines of therapy available are limited. This disease affects pediatric patients (PP) more often than adults (AP), and reported outcomes are worse for AP onset EWS in the literature. It is unclear if this is due to difference in the biology of disease in AP compared to PP, or if this is due to differences in treatment approach. Furthermore, optimal treatments and real world impact of treatment is unclear in both the PP and AP populations. This study identifies the features of therapy received by AP and PP with EWS in a large, mutli-institutional cohort, and provides real world evidence for the expected outcomes in both AP and PP with EWS. Methods: A cohort study analysis of the Sarcoma Outcomes Unit database at BC Cancer was conducted to identify patients diagnosed with EWS in British Columbia from January 1, 2000 to December 31, 2018. Data on the frequency, amount, and regimen of chemotherapy were collected. Baseline Charlson comorbidity index, age at diagnosis, progression free survival and overall survival were collected. Results: 108 patients with EWS were identified, 66 AP and 42 PP Median age at diagnosis for adults was 37 (19-86) and median age for diagnosis of pediatric patients was 14 (1-18). Real world median PFS and OS for AP were 23 mos and 79 mos, and for the PP were 32 mos and NE. Five year overall survival was 54% in AP and 77% in PP. Overall, there was no difference in the number of lines of therapy received between PP and AP, but the type of therapy was more dose-dense in the PP than in the AP, (85% vs 28% for dose dense chemo). 5 year overall survival was longer for PP who received dose dense regimens compared to non-dose dense regimens (HR 0.87), but was not different in the AP receiving dose dense regimens (HR 0.95), even when controlling for comorbidities. The most common chemotherapy regimen for AP was Vincristine, Adriamycin, cyclophosphamide alternating with Ifosfamide and Etoposide q3weeks, whereas in the pediatric population the most common chemotherapy regimen was the same but alternating q2weeks. Conclusions: The treatment plans for PP with EWS were more often dose dense compared to the AP. Outcomes for PP were vastly better than for APs, despite overall similarities in the number of lines of therapy and types of agents used. Given the lack of difference between dose dense and non-dose dense regimens for APs, this is not the likely cause of difference in survival between PPs and APs. Extrapolating pediatric protocols to the adult setting may not be appropriate given the differences in outcomes. Further work to identify effective therapies and predictive biomarkers in this disease are needed, and my further identify reasons for discrepant outcomes in pediatric and adult populations.

Does the time from diagnostic biopsy to neoadjuvant chemotherapy affect the rate of pathologic complete response in stages I-III breast cancer?

Background

Studies in the adjuvant setting suggest that the timing of breast cancer diagnosis, surgery, and chemotherapy might affect outcomes. In the neoadjuvant setting, data exploring whether expeditious neoadjuvant chemotherapy (nac) after diagnosis improves the rate of pathologic complete response (pcr) in breast cancer are limited.

Methods

Patients who received nac and completed treatment between May 2012 and December 2018 were identified from a prospectively collected database at BC Cancer. Time from diagnosis to start of nac was calculated. Patients were grouped into those who did and did not experience a pcr, and those who started nac within 28 days or after 28 days [time to nac (ttn)]. The association between pcr and ttn was tested using logistic regression.

Results

In the time period studied, 482 patients who received nac were identified. After exclusions, 421 patients met the eligibility criteria. Median time from biopsy to chemotherapy was 33 days (range: 7-140 days). In 149 patients (35.4%), nac was received within 28 days of diagnosis (range: 7-28 days); in 272 patients (64.6%), it was received after more than 28 days (range: 29-140 days). The overall pcr rate was 31.8%. A trend toward a higher pcr rate, although not statistically significant, was observed in the group that initiated chemotherapy within 28 days (34.2% vs. 30.5%, p = 0.43). In the logistic regression model, rates of pcr were associated with receptor status, but not age, stage, or ttn.

Conclusions

In the neoadjuvant setting, we observed no difference in the rate of pcr in patients who started nac within 28 days or after 28 days.

Abstract P5-13-04: Needle-to-knife wait time and impact on pCR in patients undergoing neoadjuvant chemotherapy for breast cancer

Introduction: In the setting of pre-operative neoadjuvant chemotherapy (NAC) for the treatment of breast cancer, it is important to ensure coordination between medical and surgical oncology. A study by Sanford et al. show that patients receiving surgery >8 weeks after NAC have worse overall survival. As NAC continues to expand its role in breast cancer treatment, a closer look at the maximal acceptable time between NAC and surgery becomes more important. We wished to assess the impact of time between last dose of chemotherapy and surgery on pathological complete response (pCR), disease free survival (DFS), overall survival (OS), and surgical complications.

Methods: A cohort study was conducted utilizing the BC Cancer Agency's prospective neoadjuvant database, located in Vancouver, BC. Patients were selected if they had undergone NAC with curative intent for treatment of breast cancer, followed by surgical resection. Patients who received neoadjuvant radiation and/or hormone therapy were excluded. Patients were divided into three groups: those who had surgery <4 weeks from last dose of chemo, 4-8 weeks from last dose, and >8 weeks from last dose. Charts were audited for demographic data, tumour characteristics, and complications from surgery. Data was analyzed using a Chi Squared test to determine any differences in pCR, OS, DFS, and surgical complications, between the three different time intervals.

Results: 347 patients were identified and included in this study. The median time to surgery after last dose of chemotherapy was 4.86 weeks (range 0.86-22.86 weeks). The percentage of patients that achieved pCR was 31.3%, 30.5%, and 28.6% in the <4 weeks, 4-8 weeks, and >8 weeks groups respectively (p= NS for all comparisons). There was no difference in pCR observed between the three groups based on receptor status. At the median follow up of 3 years, DFS was 85%, 85.8%, and 85.7% in all three groups. Likewise OS was 95%, 90%, and 89% respectively. The rate of surgical complications are 16%, 23.4%, and 21.4% for the three groups respectively (p=NS).

Conclusions: This study demonstrated no difference between receiving surgery <4 weeks, 4-8 weeks, or >8 weeks after last dose of NAC on pCR, survival, or surgical complications. This finding was preserved in all receptor subtypes. This has important implications for resource allocation. This data may also help in counselling and easing patient anxiety in terms of the urgency (or lack thereof) and wait times for surgery. Subsequent studies with larger sample sizes will help to ensure that clinical differences in outcomes are not affected by wait times.

Comparison of outcome measures based on needle to knife time < 4 weeks (n=80)4-8 weeks (n=239)>8weeks (n=28)p (<4 weeks vs. < 8 weeks)pCR31.3% (25)30.5% (73)28.6% (8)0.791HR+Her2-4.5% (1/22)6.5% (6/92)0% (0/5)--TNBC31.5% (6/19)42.1% (24/57)0% (0/6)--Her2+46.1% (18/39)48.8% (44/90)47.1% (8/17)--3 year DFS85%85.5%85.7%0.9273 year OS95%90%89%0.290Surgical Complication16.3%23.4%21.4%0.536

Citation Format: Lai V, Hajjaj O, Chia S, Simmons C. Needle-to-knife wait time and impact on pCR in patients undergoing neoadjuvant chemotherapy for breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-13-04.