Do the 2013 United States Preventive Services Task Force guidelines for lung cancer screening fail high-risk African American smokers? An institutional retrospective observational cohort study.

BACKGROUND: Lung cancer cause nearly 1.76 million deaths worldwide in 2018. In 2011, the National-Lung-Cancer-Screening-Trial showed 20% relative risk reduction with LDCT and subsequently led to the current USPSTF screening guidelines. However, the predominant focus on elderly, Caucasian questions its generalizability to communities with young, African Americans such as our institution. Hence, the objective of our study is to investigate the need to modify the current screening guidelines at our institution by assessing the applicability of newer individual risk-based prediction models for LDCT screening. METHODS: This is a retrospective observational cohort study of newly diagnosed lung cancer patients at LSU Health Sciences Center Shreveport from 2011 to 2015. One-third of the patients did not meet the current USPSTF screening guidelines. We categorized them into high-risk (groups1 and 2), moderate-risk, and low-risk according to 2018 NCCN Lung Cancer Screening Guidelines Version 1.2020. The high-risk groups were differentiated using the Tammemagi lung cancer risk calculator. RESULTS: Among those who did not meet the screening guidelines, nearly 50% were African American, 95% with known smoking history, and 80% diagnosed at advanced stage at the time of diagnosis. After employing the Tammemagi Risk based calculator, 12.5% were categorized into high-risk group 2, who are also eligible for annual LDCT. CONCLUSION: The current USPSTF guidelines have failed in our population consisting of young African American smokers, questioning the health disparity in medicine. By employing individual risk-based prediction models, we could potentially identify tailored high-risk populations leading to appropriate use of LDCT screening.

Cancer-Related Pneumopericardium: A Case Report and Literature Review.

Pneumopericardium is a relatively rare entity mostly described in the literature as a result of causes such as penetrating/blunt trauma and iatrogenic causes during cardiothoracic procedures. We are presenting a case of pneumopericardium as a complication of progressed gastroesophageal junction tumor along with a literature review of all cancer-related pneumopericardium cases reported in the last decade. We present the case of a 65-year-old male with a past medical history significant for locally advanced gastroesophageal junction adenocarcinoma who presented to the hospital with complaints of shortness of breath and fever. A chest X-ray showed an intact esophageal stent along with radiolucency around the cardiac silhouette which suggested pneumopericardium. Computed tomography scan of the chest confirmed the presence of pneumopericardium in posterior pericardium with foci of gas above the esophageal stent likely to be communicating with the pericardium. An echocardiogram was obtained which showed no signs of tamponade. Given the advanced nature of the disease we applied a conservative management given that the pneumopericardium was deemed to be small with no tamponade. Goals of care were discussed with the patient and his family and the patient opted for comfort care measures. This case report prompted us to perform an extensive literature review of cancer-related pneumopericardium from 2008 to 2019. We found 11 cases where it was reported secondary to malignancies of different kinds. Our aim is to compile a review for clinicians to view varied presentations and better direct therapy dependent on the individual case and clinical presentation in patients with cancer-related pneumopericardium. Moreover, although pneumopericardium is rare, it should be considered in differential diagnosis in patients presenting with shortness of breath or chest pain especially with cancers involving the cardiothoracic region.

Investigating the prevalence of queuine in Escherichia coli RNA via incorporation of the tritium-labeled precursor, preQ(1).

There are over 100 modified bases that occur in RNA with the majority found in transfer RNA. It has been widely believed that the queuine modification is limited to four transfer RNA species in vivo. However, given the vast amount of the human genome (60-70%) that is transcribed into non-coding RNA (Mattick [10]), probing the presence of modified bases in these RNAs is of fundamental importance. The mechanism of incorporation of queuine, via transglycosylation, makes this uniquely poised to probe base modification in RNA. Results of incubations of Escherichia coli cell cultures with [(3)H] preQ(1) (a queuine precursor in eubacteria) clearly demonstrate preQ(1) incorporation into a number of RNA species of various sizes larger than transfer RNA. Specifically, significant levels of preQ(1) incorporation into ribosomal RNA are observed. The modification of other large RNAs was also observed. These results confirm that non-coding RNAs contain modified bases and lead to the supposition that these modifications are necessary to control non-coding RNA structure and function as has been shown for transfer RNA.