Lazertinib is an oral, third-generation, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for the treatment of non-small cell lung cancer (NSCLC). This case report presents a rare instance of small cell carcinoma transformation in pancreatic metastasis in a patient with EGFR-mutated NSCLC undergoing treatment with lazertinib. Small cell carcinoma transformation indicates a mechanism of treatment resistance, and tissue biopsy is essential to confirm this. When isolated progression of a lesion is suspected during TKI therapy in EGFR-mutated NSCLC, histological evaluation is necessary to confirm the transformation for the treatment strategy.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Lazertinib is an oral, third-generation, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for the treatment of non-small cell lung cancer (NSCLC). This case report presents a rare instance of small cell carcinoma transformation in pancreatic metastasis in a patient with EGFR-mutated NSCLC undergoing treatment with lazertinib. Small cell carcinoma transformation indicates a mechanism of treatment resistance, and tissue biopsy is essential to confirm this. When isolated progression of a lesion is suspected during TKI therapy in EGFR-mutated NSCLC, histological evaluation is necessary to confirm the transformation for the treatment strategy.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Objectives: The standard first-line treatment for Helicobacter pylori infection typically involves proton pump inhibitors, amoxicillin, and clarithromycin (PAC), yet the eradication success rates are not entirely satisfactory. Recognizing bismuth’s antibacterial properties and its potential to enhance antibiotic efficacy, this study compared the eradication success rates of a 7-day course of PAC with bismuth (PACB) versus PAC alone in patients with clarithromycin-susceptible H. pylori infections. Methods: We conducted a retrospective review at Eunpyeong St. Mary’s Hospital involving 499 patients with confirmed clarithromycin-susceptible H. pylori infection. These patients were treated either with PACB or PAC for 7 days. Clarithromycin resistance-associated point mutations were evaluated using reverse transcriptase polymerase chain reaction. Successful eradication was confirmed by a negative 13C-urea breath test. Results: Of the patients, 261 received PACB therapy, and 238 received PAC therapy. The intention-to-treat analysis showed eradication success rates of 82.8% (216/261) for PACB and 89.1% (212/238) for PAC (p=0.093). The per-protocol analysis revealed eradication rates of 85.3% (215/252) for PACB and 90.5% (210/232) for PAC (p=0.081). The incidence of adverse effects was similar between the two groups, with 41.3% (104/252) in the PACB group and 34.1% (79/232) in the PAC group (p=0.102). Conclusions Adding bismuth to the standard 7-day PAC regimen did not significantly increase eradication rates in patients with clarithromycin-susceptible H. pylori infections compared to PAC alone.

Purpose: In this study, we investigated the effect of bisphenol-A (BPA) and its major analogs, bisphenol-F (BPF), and bisphenol-S (BPS), on spermatogonial stem cells (SSCs) populations using in vitro SSC culture and in vivo transplantation models. Materials and Methods: SSCs enriched from 6- to 8-day-old C57BL/6-eGFP+ male mice testes were treated with varying concentrations of bisphenols for 7 days to examine bisphenol-derived cytotoxicity and changes in SSC characteristics. We utilized flow cytometry, immunocytochemistry, real-time quantitative reverse transcription-PCR, and western blot analysis. The functional alteration of SSCs was further investigated by examining donor SSC-derived spermatogenesis evaluation through in vivo transplantation and subsequent testis analysis. Results: BPF exhibited a similar inhibitory effect on SSCs as BPA, demonstrating a significant decrease in SSC survival, inhibition of proliferation, and induction of apoptosis. On the other hand, while BPS was comparatively weaker than BPA and BPF, it still showed significant SSC cytotoxicity. Importantly, SSCs exposed to BPA, BPF, and BPS exhibited a significant reduction in donor SSC-derived germ cell colonies per total number of cultured cells, indicating that, like BPA, BPF, and BPS can induce a comparable reduction in functional SSCs in the recipient animals. However, the progress of spermatogenesis, as evidenced by histochemistry and the expressions of PCNA and SSC specific markers, collectively indicates that BPA, BPF, and BPS may not adversely affect the spermatogenesis. Conclusions Our findings indicate that the major BPA substitutes, BPF and BPS, have significant cytotoxic effects on SSCs, similar to BPA. These effects may lead to a reduction in the functional self-renewal stem cell population and potential impacts on male fertility.