Previous studies have shown that singlestranded RNA (ssRNA) mixed with protamine forms particles and activates immune cells through Toll-like receptors (TLRs). We have found that the size of protamine-RNA particles generated depends on the electrolyte content when mixing the 2 components. Moreover, we have evidenced that (1) nanometric particles induce production of interferon-␣, whereas (2) micrometric particles mainly induce production of tumor necrosis factor-␣ (TNF-␣) in human immune cells. We found that the mechanisms underlying these observations are (1) nanoparticles but not microparticles are selectively phagocytosed by plasmacytoid dendritic cells (pDCs), which produce interferon-␣ and (2) monocytes that produce TNF-␣ have a higher activation threshold than that of pDCs. Thus, at the same time as sensing pathogen-associated molecular patterns such as ssRNA, the immune system distinguishes the size of the associated structure in such a way as to trigger the adapted antivirus (
Assessment of tumor response after chemotherapy using 18F-FDG PET metrics is gaining acceptance. Several studies have suggested that the parameters metabolically active tumor volume (MTV) and total lesion glycolysis (TLG) are superior to SUVmax for measuring tumor burden. However, the measurement of MTV and TLG is still controversial; the most common method uses an absolute threshold of 42% of SUVmax. Recently, we implemented a background-adaptive method to determine the background-subtracted lesion activity (BSL) and the background-subtracted volume (BSV). In this study, we investigated the correlation between such PET metrics and histopathologic response in non–small cell lung carcinoma (NSCLC).
Methods
Forty-four NSCLC patients were retrospectively identified. Their PET/CT data on both types of scan before and after neoadjuvant chemotherapy were analyzed regarding SUVmax, MTV, TLG, BSL, and BSV, as well as the relative changes in these parameters. The tumor regression score as an indicator of histopathologic response was scored on hematoxylin- and eosin-stained sections of the surgical specimens using a 4-tiered scale (scores 1–4). The correlation between score and the absolute and relative PET metrics after chemotherapy was analyzed using Spearman rank correlation tests.
Results
Tumors that demonstrated a good response after neoadjuvant chemotherapy had significantly lower 18F-FDG activity than non-responding tumors (scores 3 and 4: SUVmax, 4.2 [range, 1.8–7.9] vs. scores 1 and 2: SUVmax, 8.1 [range, 1.4–40.4]; P = 0.001). The same was found for change in SUVmax and score (P = 0.001). PET volume metrics based on a 42% fixed threshold for SUVmax did not correlate with score (TLG, P = 0.505; MTV, P = 0.386). However, both background activity–based PET volume metrics—BSL and BSV—significantly correlated with score (P < 0.001 each).
Conclusion
PET volume metrics based on background-adaptive methods correlate better with histopathologic score in NSCLC patients under neoadjuvant chemotherapy than algorithms and methods using a fixed threshold (42% SUVmax).
Background
The COVID-19 pandemic has impacted all aspects of modern-day oncology, including how stakeholders communicate through social media. We surveyed oncology stakeholders in order to assess their attitudes pertaining to social media and how it has been affected during the pandemic.
Materials and methods
A 40-item survey was distributed to stakeholders from 8 July to 22 July 2020 and was promoted through the European Society for Medical Oncology (ESMO) and the OncoAlert Network.
Results
One thousand and seventy-six physicians and stakeholders took part in the survey. In total, 57.3% of respondents were medical oncologists, 50.6% aged <40 years, 50.8% of female gender and mostly practicing in Europe (51.5%). More than 90% of respondents considered social media a useful tool for distributing scientific information and for education. Most used social media to stay up to date on cancer care in general (62.5%) and cancer care during COVID-19 (61%) given the constant flow of information. Respondents also used social media to interact with other oncologists (78.8%) and with patients (34.4%). Overall, 61.1% of respondents were satisfied with the role that social media was playing during the COVID-19 pandemic. On the other hand, 41.1% of respondents reported trouble in discriminating between credible and less credible information and 30% stated social networks were a source of stress. For this reason, one-third of respondents reduced its use during the COVID-19 pandemic. Regarding meeting attendance, a total of 59.1% of responding physicians preferred in-person meetings to virtual ones, and 51.8% agreed that virtual meetings and social distancing could hamper effective collaboration.
Conclusion
Social media has a useful role in supporting cancer care and professional engagement in oncology. Although one-third of respondents reported reduced use of social media due to stress during the COVID-19 pandemic, the majority found social media useful to keep up to date and were satisfied with the role social media was playing during the pandemic.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.