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Leiomyosarcoma of the ovary is a rare disease, with aggressive behavior and poor prognosis, which mainly occurs in postmenopausal women. Surgery is the cornerstone of treatment, while the role of chemotherapy and radiotherapy is still not clear because substantial data is lacking. This paper presents the case of an adult woman who is diagnosed with primary leiomyosarcoma of the left ovary, and who receives a surgical approach and adjuvant treatment with chemotherapy currently achieving 20 months free from disease.

Our findings raise the need to carefully evaluate patients with metastatic cancer, in progression, and with impaired ECOG to define the relevance of cancer treatment during the pandemic, consider the risk/benefit of the interventions, and establish clear and complete communication with the patients and their families about the risk of complications. There is also the importance of offering additional support to patients with low income and residence in rural areas so that they can have more support during cancer treatment.

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counterintuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfvén waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, α = 2 as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed >600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: preflare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that α = 1.63 ± 0.03. This is below the critical threshold, suggesting that Alfvén waves are an important driver of coronal heating.

e18761 Background: Cancer has been described as a risk factor for worse prognosis in people with Covid-19. However, there are few studies informing on the characteristics of cancer patients that have asymptomatic SARS-cov2 infection. The ACHOCC-19 study included asymptomatic patients. Methods: Analytical cohort study of patients with cancer and SARS-cov2 infection in Colombia. From April 1 to October 31, 2020, we collected data on demographic and clinical variables related to cancer and COVID-19 infection. We describe the characteristics and outcomes of patients who had no symptoms of COVID19. Association between outcomes and prognostic variables was analyzed using logistic regression models. Results: We included 742 patients, of which 205 (27.6%) were asymptomatic. Of these 62.2% were older than 61 years, 66% were women, 1.42% were smokers. The most frequent malignancy was breast cancer (25%), followed by colon-rectum (14.6%), sarcoma/soft tissues (5.66%) and lung cancer (5.19%). Patients were more likely to be asymptomatic if they had fewer comorbidities (0-1 comorbidities: 84% asymptomatic, 2 comorbidities: 10.85%, more than 2 comorbidities: 5.15%). 90.5% lived in urban areas and 53.37% had low income. 35.4% of patients had metastatic disease, 8.7% had progressive cancer, 40% had stable disease or partial response. No patient had an ECOG PS of 4 or more, and only 1.91% had ECOG 3. In logistic regression analysis statistically significant associations for having symptomatic disease included: man, presence of 1, 2 or > 2 comorbidities, ECOG 1,2 or 3 and cancer in progression. On the other hand, the statistically significant ORs for having asymptomatic disease were age between 18 and 30 years old, cancer in remission and receiving non-cytotoxic treatment. Table sumarizes ORs and their respective 95% CIs of the variables adjusted in the logistic regression model. Conclusions: In our stumdy, cancer patients had a higher probability of asymptomatic COVID-19 infection if they were women, between the ages of 18 and 30 years, had cancer in remission , ECOG 0 and no comorbidities. This is the first cohort of patients with cancer and asymptomatic covid 19 with a significant sample size in Latin America.[Table: see text]