Influenza Among Breast Cancer Survivors in South Korea: A Nationwide Population-Based Study

Breast Cancer Survivors and COVID-19: Prevalence and Risk of Severe Disease in a Screening Study

Background

Determining the risk of severe course coronavirus disease 2019 (COVID-19) and its related factors in survivors of common cancers such as breast cancer is important. This study has been designed to evaluate the prevalence of COVID-19 infection in breast cancer survivors and also estimate the risk of severe disease in this population.

Methods

Out of 6134 patients in the Shiraz Breast Cancer Registry (SBCR), A total of 292 patients who elapsed less than a year from their breast cancer diagnosis were excluded. We called 5842 patients. Finally, 4135 breast cancer survivors who agreed to cooperate were screened for COVID-19 symptoms by a symptom-based questionnaire in November 2020. COVID-19 in symptomatic participants was confirmed by a polymerase chain reaction (PCR) test. The clinical and paraclinical data of the COVID-19 course were collected for patients with a positive PCR test.

Results

A total of 247 (5.9%) participants had at least reported one of the COVID-19 symptoms. Also, 17% of symptomatic participants had a positive PCR test; 83.7% had mild disease, 9.5% moderate, and 16.7% had severe conditions. Chronic cardiovascular disease, hypertension, and diabetes were related to an increased risk of severe illness ( P = 0.018, P = 0.018, P = 0.002).

Conclusion

This study suggests that breast cancer intermediate and longtime survivors without other underlying diseases are considered at low risk for developing severe/critical COVID-19.

Anti-cancer Therapy Leads to Increased Cardiovascular Susceptibility to COVID-19

Anti-cancer treatment regimens can lead to both acute- and long-term myocardial injury due to off-target effects. Besides, cancer patients and survivors are severely immunocompromised due to the harsh effect of anti-cancer therapy targeting the bone marrow cells. Cancer patients and survivors can therefore be potentially extremely clinically vulnerable and at risk from infectious diseases. The recent global outbreak of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its infection called coronavirus disease 2019 (COVID-19) has rapidly become a worldwide health emergency, and on March 11, 2020, COVID-19 was declared a global pandemic by the World Health Organization (WHO). A high fatality rate has been reported in COVID-19 patients suffering from underlying cardiovascular diseases. This highlights the critical and crucial aspect of monitoring cancer patients and survivors for potential cardiovascular complications during this unprecedented health crisis involving the progressive worldwide spread of COVID-19. COVID-19 is primarily a respiratory disease; however, COVID-19 has shown cardiac injury symptoms similar to the cardiotoxicity associated with anti-cancer therapy, including arrhythmia, myocardial injury and infarction, and heart failure. Due to the significant prevalence of micro- and macro-emboli and damaged vessels, clinicians worldwide have begun to consider whether COVID-19 may in fact be as much a vascular disease as a respiratory disease. However, the underlying mechanisms and pathways facilitating the COVID-19-induced cardiac injury in cancer and non-cancer patients remain unclear. Investigations into whether COVID-19 cardiac injury and anti-cancer drug-induced cardiac injury in cancer patients and survivors might synergistically increase the cardiovascular complications and comorbidity risk through a “two-hit” model are needed. Identification of cardiac injury mechanisms and pathways associated with COVID-19 development overlapping with anti-cancer therapy could help clinicians to allow a more optimized prognosis and treatment of cancer survivors suffering from COVID-19. The following review will focus on summarizing the harmful cardiovascular risk of COVID-19 in cancer patients and survivors treated with an anti-cancer drug. This review will improve the knowledge of COVID-19 impact in the field of cardio-oncology and potentially improve the outcome of patients.

Care for Breast Cancer Survivors

The number of cancer survivors is increasing globally. More than 15.5 million Americans in 2016 and 1.3 million Koreans in 2013 were living with cancer history. This growing population is expected to increase due to marked development of cancer treatment and early detection. Especially, breast cancer is the second most common cancer in Korean women with relatively favorable 5-year survival rate. Cancer survivors generally face various physical, psychological, and social problems including late-effect or long-term effect after cancer treatment and high risk for second primary cancer and comorbid chronic diseases such as cardiovascular disease and bone health. Breast cancer survivors also encounter wide range of health problems. To satisfy their complex needs, comprehensive supports are required. We categorized the strategy of comprehensive care for breast cancer survivors into (1) Surveillance for primary cancer, (2) Screening of second primary cancer, (3) Management of comorbid health condition, (4) Promoting healthy lifestyle behaviors, and (5) Preventive care. In the future, studies for providing best comprehensive care for breast cancer survivors are needed according to the individuals' demand.

Prevalence of COVID-19-related risk factors and risk of severe influenza outcomes in cancer survivors: A matched cohort study using linked English electronic health records data

BACKGROUND

People with active cancer are recognised as at risk of COVID-19 complications, but it is unclear whether the much larger population of cancer survivors is at elevated risk. We aimed to address this by comparing cancer survivors and cancer-free controls for (i) prevalence of comorbidities considered risk factors for COVID-19; and (ii) risk of severe influenza, as a marker of susceptibility to severe outcomes from epidemic respiratory viruses.

METHODS

We included survivors (≥1 year) of the 20 most common cancers, and age, sex and general practice-matched cancer-free controls, derived from English primary care data linked to cancer registrations, hospital admissions and death registrations. Comorbidity prevalences were calculated 1 and 5 years from cancer diagnosis. Risk of hospitalisation or death due to influenza was compared using Cox models adjusted for baseline demographics and comorbidities.

FINDINGS

108,215 cancer survivors and 523,541 cancer-free controls were included. Cancer survivors had more diabetes, asthma, other respiratory, cardiac, neurological, renal, and liver diseases, and less obesity, compared with controls, but there was variation by cancer site. There were 205 influenza hospitalisations/deaths, with cancer survivors at higher risk than controls (adjusted HR 2.78, 95% CI 2.04-3.80). Haematological cancer survivors had large elevated risks persisting for >10 years (HR overall 15.17, 7.84-29.35; HR >10 years from cancer diagnosis 10.06, 2.47-40.93). Survivors of other cancers had evidence of raised risk up to 5 years from cancer diagnosis only (HR >5 years 2.22, 1.31-3.74).

INTERPRETATION

Risks of severe COVID-19 outcomes are likely to be elevated in cancer survivors. This should be taken into account in policies targeted at clinical risk groups, and vaccination for both influenza, and, when available, COVID-19, should be encouraged in cancer survivors.

Factors associated with pneumococcal vaccination uptake by cancer survivors

PURPOSE

This study aimed to evaluate factors associated with pneumococcal vaccination uptake (PVU) of cancer survivors.

METHODS

A total of 2032 Korean adult cancer survivors diagnosed between June of 1975 and February of 2018 have participated. Information on PVU status and selected variables were collected through self-administered questionnaires and medical record review. Factors associated PVU were investigated using multiple logistic regression analysis.

RESULTS

PVU rate markedly differed by age strata and cancer sites: 73.9% for elderly (≥ 65 years) survivors and 34.6% for younger (< 65 years) survivors and 73.4% for lung cancer survivors and 42.1% for non-lung cancer survivors. Regular physical exercise was associated with higher PVU in both age groups: Odds ratio (OR) and 95% confidence interval (CI) were 1.52 (1.20, 1.94) for younger and 1.78 (1.09, 2.90) for elderly survivors. Complementary medication use was positively associated with PVU with borderline significance in both age groups. However, the association of PVU with other factors differed between the two age groups. In younger survivors, a positive association with PVU was evident for longer time lapse after cancer diagnosis, chronic disease, and living with spouse/or partner, while cancer stage, educational achievement, and alcohol use were inversely associated PVU. On the other hand, multi-modality (≥ 3) cancer treatment was inversely associated with PVU only in elderly survivors.

CONCLUSIONS

PVU of Korean cancer survivors was suboptimal in younger survivors and non-lung cancer survivors. Factors associated with PVU differed between younger and elderly survivors, and more diverse factors were identified for younger survivors.

IMPLICATIONS FOR CANCER SURVIVORS

In order to promote adherence to PVU in cancer survivors, careful consideration of high-risk factors for non-immunization within cancer survivorship context would be necessary together with free-of-charge vaccination policy.

Trends in Influenza Vaccination Coverage Rates among Korean Cancer Survivors: Analysis of the Korea National Health and Nutrition Examination Survey III-VI

Background

Few studies have reported on the trends in influenza vaccination rates among cancer survivors in Korea. We investigated these trends over a recent 11-year period (2005–2015).

Methods

Data were obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) III– VI (2005–2015). After excluding individuals younger than 40 years of age, the participants included 2,210 cancer survivors (861 men and 1,349 women). We categorized these study participants into four groups according to age and sex.

Results

The influenza vaccination rate decreased significantly among male cancer survivors, with rates of 74.8, 64.7, 56.2, and 55.2% (β coefficient=-0.257, P for trend <0.001) in KNHANES III, VI, V, and VI, respectively. While influenza vaccination rates decreased significantly among older male cancer survivors (≥65 years) (β coefficient=-0.359, P for trend=0.017), they increased among older female cancer survivors (β coefficient=0.375, P for trend=0.011) from 2005 to 2015.

Conclusion

Influenza vaccination rates in older cancer survivors significantly decreased in men but increased in women in successive KNHANES phases. Efforts are needed to improve immunization education and awareness, especially in older male cancer survivors.