Importance of mediastinal granulomatous/sarcoid-like lymphadenopathy in extrathoracic malignancies.

BACKGROUND: In patients with extrathoracic malignancies (ETM), granulomatous lymph adenopathy called sarcoid-like reactions (SLR) can be seen in the regional or draining lymph nodes. We hypothesized that SLR may be a sign of imminent metastasis and investigated the clinical course and rate of recurrence in patients with ETM and granulomatous mediastinal lymphadenopathy (MLN). METHODS: In this retrospective observational study, we reviewed the medical files of patients with known ETM and who underwent EBUS-TBNA for initial staging or detection of recurrence from 2011 to 2023. Patients with granulomatous MLN were included. RESULTS: Forty-one patients (29 female) enrolled in the study. Breast and colorectal carcinomas were the most common malignancies. A total of 81 lymph nodes were sampled. The final diagnosis of patients was five sarcoidosis, one tuberculosis, one second primary, one drug reaction, and 33 SLR. Among patients with SLR, in one patient lymph nodes progressed during the follow-up and were accepted as false-negative without confirmatory biopsy. The negative predictive value (NPV) of granulomatous MLN for metastasis was 97.05%. CONCLUSION: Granulomatous MLN may be due to tuberculosis, drug reaction, sarcoidosis, or SLR in patients with ETM. SLR has a high NPV in patients with ETM. Follow-up imaging rather than confirmatory biopsy is reasonable in these patients.

Role of Vitamin D, ACE2 and the Proteases as TMPRSS2 and Furin on SARS-CoV-2 Pathogenesis and COVID-19 Severity.

BACKGROUND: COVID-19, the 21st century pandemic disease caused by SARS-CoV-2, has shown a wide clinical spectrum ranging from asymptomatic to deadly serious pneumonia. OBJECTIVE: In our study, the relationship between the pathogenesis and clinical severity of COVID-19 and vitamin D, ACE2, Furin and TMPRSS2 was investigated. METHODS: Serum 25(OH)D, 1,25(OH)2D and ACE2 protein were measured in 85 COVID-19 cases, divided into 5 groups, according to disease severity, from asymptomatic to severe and including a healthy control group. Expression levels of ACE2, VDR, TMPRSS2 and Furin mRNAs in PBMC were also measured. The relationship of the parameters within each group, the severity of the disease and the effect on the patients' fate were investigated. RESULTS: Statistically significant differences were found between the severity of COVID-19 and all study parameters, except for serum 25(OH)D. A strong negative correlation was found between serum ACE2 protein, 1,25(OH)2D, and ACE2 mRNA, and disease severity, length of hospital stay and death/survival rate. Vitamin D deficiency increased the death risk by 5.6-fold (95% CI 0.75-41.47), and the levels of 1,25(OH)2D lower than 1 ng/mL increased the risk of death by 3.8-fold (95% CI 1.07-13.30). CONCLUSION: This study suggests that vitamin D supplementation could be beneficial in the treatment and/or prevention of COVID-19.