Byoung Soo Kwon

4‐1BB stimulation inhibits allergen‐specific immunoglobulin E production and airway hyper‐reactivity but partially suppresses bronchial eosinophilic inflammation in a mouse asthma model

Background 4‐1BB, a member of the tumour necrosis factor receptor superfamily, functions as a co‐stimulatory molecule. Recently, stimulation of the 4‐1BB pathway was shown to suppress antigen‐specific CD4+ T cell and subsequent T cell‐dependent humoral immune responses.

Predictive Factors for Switched EGFR-TKI Retreatment in Patients with EGFR-Mutant Non-Small Cell Lung Cancer

Background Third-generation tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR-TKIs) have proved efficacious in treating non-small cell lung cancer (NSCLC) patients with acquired resistance resulting from the T790M mutation. However, since almost 50% patients with the acquired resistance do not harbor the T790M mutation, retreatment with first- or second-generation EGFR-TKIs may be a more viable therapeutic option. Here, we identified positive response predictors to retreatment, in patients who switched to a different EGFR-TKI, following initial treatment failure. Methods This study retrospectively reviewed the medical records of 42 NSCLC patients with EGFR mutations, whose cancers had progressed following initial treatment with gefitinib or erlotinib, and who had switched to a different first-generation EGFR-TKI during subsequent retreatment. To identify high response rate predictors in the changed EGFR-TKI retreatment, we analyzed the relationship between clinical and demographic parameters, and positive clinical outcomes, following retreatment with EGFR-TKI. Results Overall, 30 (71.4%) patients received gefitinib and 12 (28.6%) patients received erlotinib as their first EGFR-TKI treatment. Following retreatment with a different EGFR-TKI, the overall response and disease control rates were 21.4% and 64.3%, respectively. There was no significant association between their overall responses. The median progression-free survival (PFS) after retreatment was 2.0 months. However, PFS was significantly longer in patients whose time to progression was ≥10 months following initial EGFR-TKI treatment, who had a mutation of exon 19, or whose treatment interval was <90 days. Conclusion In patients with acquired resistance to initial EGFR-TKI therapy, switched EGFR-TKI retreatment may be a salvage therapy for individuals possessing positive retreatment response predictors.

Feasibility of Endovascular Catheter Biopsy as a Diagnostic Modality for Patients With Pulmonary Artery Sarcoma: Case Series of a Single-Center Experience

Pulmonary artery sarcoma (PAS) is a rare but lethal malignant neoplasm that often mimics pulmonary artery embolism. However, owing to its rarity as well as fatality, there has been no firm consensus with regard to the standard diagnostic tool. We evaluate the feasibility of endovascular catheter biopsy as a diagnostic modality for PAS. We retrospectively reviewed the medical records of patients with histologically confirmed PAS between 2000 and 2016 at Asan Medical Center. Among a total of 25 patients with PAS, 5 patients underwent endovascular catheter biopsy and 3 of them were successfully diagnosed with PAS, while 2 patients underwent either endobronchial ultrasonography–transbronchial needle aspiration or surgical biopsy after failure of endovascular biopsy. There were no acute or fatal complications of endovascular catheter biopsy such as bleeding or pulmonary infarction. In conclusion, we suggest the endovascular catheter biopsy is an effective and safe diagnostic tool for patients with PAS, when clinically indicated.

The second recurrence of MAC lung disease after successful treatment for first recurrence

The recurrence rate of Mycobacterium avium complex (MAC) lung disease (LD) after successful treatment is approximately 10–48% [1–3]. These episodes represent true relapse from the same MAC strain or a reinfection with a new strain [1, 2, 4]. Nodular bronchiectatic (NB) type, old age, lower body mass index (BMI) and M. avium isolates are related to recurrence [3, 5, 6]. Approximately 60% of patients who are successfully treated for their first recurrence of MAC lung disease eventually experience a second recurrence. Approximately half of the second recurrence patients require anti-MAC treatment. http://ow.ly/3G2R30meImC

Association between duration of aminoglycoside treatment and outcome of cavitary Mycobacterium avium complex lung disease

BACKGROUND Although aminoglycosides are recommended for cavitary Mycobacterium avium complex lung disease (MAC-LD), the optimal duration of treatment is unclear. We investigated the association between duration of aminoglycoside treatment and outcomes in cavitary MAC-LD. METHODS Among patients diagnosed with macrolide-susceptible cavitary MAC-LD between 2000 and 2013, 101 who received treatment up to August 2017 with a regimen containing aminoglycosides were enrolled at a tertiary referral center in South Korea. Their medical records were retrospectively reviewed. The duration of aminoglycoside treatment was at the discretion of the attending physician. RESULTS A total of 75 patients (74.3%) were administered aminoglycosides for ≥3 months (median 164 days), whereas the remaining 26 patients (25.7%) received treatment for <3 months (median 59 days). The overall treatment success rate was 63.4% (64/101). Patients treated with aminoglycosides for ≥3 months had a significantly higher success rate than those treated for <3 months (69.3% vs 46.2%; P = .035). Multivariate analysis revealed that aminoglycoside treatment for ≥3 months was a significant factor for treatment success (adjusted odds ratio, 3.602; 95% confidence interval, 1.249-10.390; P = .018). Recurrence occurred in 8 (22.9%) of 35 patients who were followed up for at least 3 years after the end of treatment; all 8 patients received aminoglycosides for ≥3 months. CONCLUSIONS Patients with cavitary MAC-LD treated with aminoglycosides for ≥3 months showed higher treatment success rate than those treated for <3 months. However, treatment for ≥3 months was not associated with the development of recurrence.

[Primary Biliary Mucosa-associated Lymphoid Tissue Lymphoma Mimicking Hilar Cholangiocarcinoma].

Primary biliary mucosa-associated lymphoid tissue (MALT) lymphoma is extremely rare. We report a case of primary biliary MALT lymphoma with obstructive jaundice diagnosed by endoscopic biopsy, without surgical intervention. Obstructive jaundice was relieved by endoscopic drainage and endoscopic biopsy was done simultaneously during endoscopic retrograde cholangiopancreatography. Unnecessary surgical intervention can be avoided after pathological confirmation of lymphoma. The patient received radiotherapy, and is alive without any evidence of recurrence or biliary obstruction. Diagnosis of primary biliary lymphoma is very difficult because of its low prevalence. However, it should always be considered as a differential diagnosis, since when an accurate diagnosis is made, unnecessary surgical intervention can be avoided.