Background: Genetic panel tests require sufficient tissue samples, and therefore, cannot always be performed. Although collecting cytological specimens is easier than tissue collection, there are no validation studies on the diagnostic accuracy of lung cancer gene panel tests using cytology samples. Methods: Using an amplicon-based high-sensitivity next-generation sequencing panel test capable of measuring eight druggable genes, we prospectively enrolled consecutive patients who underwent diagnostic procedures. We evaluated the analysis accuracy rate, nucleic acid yield, and the quality of cytological specimens under brushing, needle aspiration, and pleural effusion. We then compared these specimens with collected tissue samples. Results: In 163 prospectively enrolled cases, nucleic acid extraction and analysis accuracy was 100% in cases diagnosed with adenocarcinoma. Gene mutations were found in 68.7% of cases with 99.5% (95% CI: 98.2–99.9) concordance to companion diagnostics. The median DNA/RNA yield and DNA/RNA integrity number were 475/321 ng and 7.9/5.7, respectively. The correlation coefficient of the gene allele ratio in 64 cases compared with tissue samples was 0.711. Conclusion: The success of gene analysis using cytological specimens was high, and the yield and quality of the extracted nucleic acid were sufficient for panel analysis. Moreover, the allele frequency of gene mutations in cytological specimens showed high correlations with tissue specimens.

Airway involvement in relapsing polychondritis (RP) can be debilitating and life threatening, often requiring interventional procedures. If standard therapies including systemic corticosteroid and immunosuppressive agents are ineffective, airway stenting is often required. Recently, biologics have been reported to be effective for RP, and the early administration of biologics may avoid airway stenting. To evaluate survival rates and treatment approaches, medical records of RP patients with airway involvement were reviewed. These cases were divided into the following groups: with and without malacia, stenting and non-stenting, and with and without biologics. Kaplan–Meier was used to calculate survival rates and log rank tests were used to analyze biologics groups. A total of 77 patients were enrolled. Airway stenting was performed in 13 patients, all of which developed airway malacia. The stenting group had significantly lower survival rates than the non-stenting group (p < 0.001). Stent-related complications were granulation tissue (85%) and mucostasis (69%). In the non-stenting group, a lower mortality rate was observed. A significantly higher survival rate was seen in patients administered biologics than without (p = 0.014). The early administration of biologics shows promise in preventing severe airway disorders that require airway stenting.

Bronchial schwannoma is extremely rare, accounting for a small percentage of benign bronchial tumors, with no determined standardized treatment. An 89-year-old woman with a persistent cough underwent CT scan which revealed a tracheal tumor. A diagnosis of endobronchial schwannoma was confirmed based on tissue obtained by high-frequency snare polypectomy. A hybrid stent was implanted in the trachea due to tumor regrowth; however, stent migration occurred, and it was removed after 1 month. Subsequently, radiation therapy was performed, and airway patency was well maintained for over 3 years. In general, surgical resection is recommended for endobronchial schwannoma; however, due to the age of this patient, resection was deemed invasive. Therefore, radiation therapy was administered as an alternative treatment.

Background: Relapsing polychondritis (RP) is a rare inflammatory disease characterized by recurrent inflammation and destruction of cartilaginous tissues. RP has characteristics of autoimmune disease and some reports have noted co-occurrence with autoimmune thyroid disease (AITD), consisting of Graves’ disease (GD) and Hashimoto thyroiditis (HT). However, there have been no detailed studies on the co-occurrence of RP and AITD. In this study, we aimed to determine whether patients with RP tend to be complicated with AITD. We also analyzed the clinical and genetic profiles of patients in whom these diseases co-occur. Methods: We recruited 117 patients with RP and reviewed their medical records. Furthermore, we genotyped Human Leucocyte Antigen (HLA)-A, B Cw, DRB1, DQB1, and DPB1 alleles for 93 of the 117 patients. The prevalence of AITD among the patients with RP was compared with that among the general Japanese population. We also analyzed the clinical and genetic features of the patients with both RP and AITD. Results: The prevalence of GD among the patients with RP was 4.3% (5 among 117 patients), significantly higher than that among Japanese (0.11%) (p = 2.44 × 10^–7, binomial test). RP patients with GD tended to have nasal involvement (p = 0.023) (odds ratio (OR) 2.58) and HLA-DPB1*02:02 (p = 0.035, OR 10.41). We did not find significant enrichment of HT in patients with RP. Conclusions: Patients with RP appear to be at elevated risk of GD. Nasal involvement and HLA-DPB1*02:02 characterize the subset of RP patients with GD, which may guide attempts to characterize a distinct subtype of RP for precision medicine.

A few studies have reported on the variability of the variant allele frequency (VAF) of gene mutations and the relationship between VAF and the therapeutic effect of molecular-targeted drugs. This joint study was conducted from May 2020 to January 2022 between St. Marianna University School of Medicine and the DNA Chip Research Institute. Cytology samples were used to verify the usefulness of a lung cancer compact panel test, which is a high-sensitivity next-generation sequencing (NGS) gene panel test. We analyzed the distribution of VAF and the duration of the initial molecular-targeted drug administration in patients with advanced-stage epidermal growth factor receptor (EGFR) mutations. Of the 196 patients diagnosed with non-small cell carcinoma (NSCLC), gene mutations were detected in 114 (58.2%) cases and in 68.7% of patients with adenocarcinomas (an increased detection rate). A VAF of 30% or more for DNA mutations was confirmed in 35 patients (33.7%), 10% to <30% in 38 (36.5%), and <10% in 31 (29.8%), including 18 patients (17.3%) with <6%, which is considered the lower limit of the LOD for other companion diagnostic kits. EGFR mutations were detected in 59 patients (30%), of whom 35 were in an advanced stage and received molecular-targeted drugs as their initial treatment. Groups A and B comprised patients with a VAF of ≥10% and <10%, respectively, with 27 patients (median VAF 30.6%, range 11.4–77%) in group A and 8 (median VAF 5.4%, range 0.1–8.5%) in group B. The duration of the administration of molecular-targeted drugs was 17 months (range 3–42 months) in group A and 14 months (range 1–45 months) in group B, with no statistically significant difference between the two groups (p-value = 0.7). Twenty-seven percent of patients had a VAF < 10%. Even in patients with a low VAF for gene mutations, sufficient therapeutic effects were observed with molecular-targeted drugs, suggesting the importance of detecting mutations using a highly sensitive method at initial diagnosis. Further prospective validation studies of a larger number of cases are warranted.

Recently, several biologics have been approved for the treatment of severe asthma. Dupilumab, a biologic used to treat severe asthma, is a monoclonal antibody targeting interleukin-4 and interleukin-13. In the present case, inhaled corticosteroid-induced glucocorticoid hypersensitivity was suspected, and the administration of omalizumab and mepolizumab had no beneficial effects. Subsequently, we switched to dupilumab therapy, which produced better effectiveness. Therefore, when a biologic agent proves ineffective, changing to another suitable biologic agent should be considered.