Real-World Treatment Patterns and Patient-Reported Outcomes in Chronic Obstructive Pulmonary Disease in Japan: The REMIND Study.

INTRODUCTION: Symptom status and treatment changes among patients with chronic obstructive pulmonary disease (COPD) using inhaler treatment in real-world clinical settings are not well understood, particularly according to class of treatment. We investigated the proportion of symptomatic patients among those with COPD using inhaler treatment, based on COPD Assessment Test (CAT) scores in clinical practice, and changes in inhaler treatments and symptoms at 1-year follow-up. METHODS: This was a retrospective analysis of data from a multicenter, prospective cohort study conducted at medical institutions with respiratory specialists in Japan. The primary endpoint was the proportion of patients with CAT scores ≥ 10 or < 10 in each inhaler treatment group at registration. RESULTS: Of 414 patients in the full analysis set, 76 (18.4%), 261 (63.0%), and 77 (18.6%) were using long-acting muscarinic antagonist (LAMA), LAMA + long-acting ß2-agonist (LABA), and inhaled corticosteroids (ICS) + LABA, respectively, at registration. The proportions of patients with CAT scores ≥ 10 or < 10 per inhaler treatment group at registration, respectively, were 32.9% and 67.1% in the LAMA group, 55.0% and 45.0% in the LAMA + LABA group, and 50.0% and 50.0% in the ICS + LABA group. Most patients (> 75%) in each inhaler treatment group showed no change in inhaler treatment at 1 year, regardless of their CAT score at registration. Approximately 70-80% of patients with CAT scores ≥ 10 at registration still had CAT scores ≥ 10 at 1 year; 10-30% of patients with CAT scores < 10 at registration had CAT scores ≥ 10 at 1 year. CONCLUSION: In real-world Japanese clinical practice, a considerable proportion of patients have persistent symptoms (CAT score ≥ 10) despite using mono or dual inhaler treatment; > 75% of symptomatic patients with COPD using inhaler treatment did not undergo treatment escalation at 1-year follow-up and remained symptomatic. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT05903989.

Suitability of frozen cell pellets from cytology specimens for the Amoy 9-in-1 assay in patients with non-small cell lung cancer.

BACKGROUND: The AmoyDx Pan lung cancer PCR panel (AmoyDx PLC panel) has been approved as a companion diagnostic tool for multiple anticancer agents in patients with non-small cell lung cancer (NSCLC). However, the suitability of cytology specimens as samples for the AmoyDx PLC panel remains unclear. We evaluated the performance of frozen cell pellets from cytology specimens (FCPs) in the Amoy 9-in-1 assay, a preapproval assay of the AmoyDx PLC panel. METHODS: We retrospectively collected data of NSCLC patients enrolled in LC-SCRUM-Asia from the Shizuoka Cancer Center between September 2019 and May 2021. RESULTS: A total of 49 cases submitted FCPs for evaluation of oncogenic driver alterations and were assessed using Amoy 9-in-1 and next-generation sequencing (NGS) assays. The success rates of DNA and RNA analyses using the Amoy 9-in-1 were both 100%, compared with 86% and 45%, respectively, using NGS assays. Oncogenic driver alterations were detected in 27 (55%) and 23 (47%) patients using Amoy 9-in-1 and NGS, respectively. No inconsistent results were observed among 19 cases in which both assays showed successful detection. In the remaining 30 cases, 10 had inconsistent results: nine oncogenic driver alterations (3 MET, 2 ALK, 2 ROS1, and 2 KRAS) were detectable only in Amoy 9-in-1, and one epidermal growth factor receptor (EGFR) mutation was detectable only in NGS. CONCLUSION: FCPs can be successfully used in the AmoyDx PLC panel, with higher success rate compared with the NGS assay. The AmoyDx PLC panel may be an option in cases when insufficient tissue sample is available for the NGS assay.

The Relationship between Leptin Levels and Continuous Positive Airway Pressure Treatment: A Cluster Analysis.

Objective Leptin is an appetite-suppressing hormone released by adipose tissue that plays an important role in severe obstructive sleep apnea syndrome (OSAS). However, it is unclear whether leptin levels are a useful biomarker for this syndrome. The present study aimed to assess the effect of continuous positive airway pressure (CPAP) treatment on the syndrome according to leptin levels, using a cluster classification based on clinical features of the syndrome. Materials and Methods We performed a hierarchical cluster analysis of data from 97 OSAS patients diagnosed via polysomnography. We also evaluated the effect after 6 months of CPAP administration. Results Clusters 1 (49 patients; 50.5%) and 2 (6 patients; 6.2%) presented normal leptin levels, and clusters 3 (11 patients; 11.3%) and 4 (31 patients; 32%) presented high leptin levels. Clusters 3 and 4 presented different leptin levels, but the same degree of obesity. After treatment, the levels of excessive daytime sleepiness improved in all clusters. In Cluster 3, leptin levels were significantly reduced after treatment. Conclusion Using the conventional diagnostic method of the apnea-hypopnea index, it was not clear whether leptin is a useful biomarker for the CPAP treatment. However, it may be helpful for particular clusters, including obese women, and where particular populations require CPAP treatment.

Validity study of the Japanese version of the Nijmegen Questionnaire for verifying dysfunctional breathing in Japanese asthma patients.

Background: Dysfunctional breathing (DB) is a clinical condition characterized by irregular breathing patterns presenting a sensation of dyspnea and a feeling of chest tightness. DB is a known comorbidity of asthma that is difficult to control, leading to poor quality of life, so early diagnosis and therapeutic intervention are essential to improve the clinical condition of asthma. The Nijmegen Questionnaire (NQ), developed to screen for DB and translated into various languages, is used worldwide. However, a Japanese NQ (JNQ) is unavailable, so DB has not been clinically verified in people with asthma in Japan. Objective: This study aimed to prepare a JNQ, verify its reliability and validity, and demonstrate its clinical benefits in asthma treatment. Methods: The JNQ was prepared by back-translating the NQ with the author's consent. The answers to self-administered questionnaires, including the JNQ, Asthma Control Test (ACT), Asthma Control Questionnaire (ACQ), Mini Asthma Quality of Life Questionnaire (Mini-AQLQ), and Patient Health Questionnaire 9 (PHQ-9), were obtained with the consent of 68 people with asthma (average age ± SD, 52.04 ± 12.43 years) who visited Nihon University Itabashi Hospital. The reliability of the JNQ was analyzed by the Cronbach alpha coefficient. A comparative test was conducted for each questionnaire (ACT, ACQ, Mini-AQLQ, PHQ-9), considering a JNQ score of 23 as the cutoff value. Patients with a score of 23 or more were assigned to the DB group, whereas patients with a score of less than 23 were assigned to the non-DB group. We analyzed the correlation between the JNQ and each questionnaire. Results: The JNQ showed sufficient reliability (Cronbach alpha = 0.875). Correlation analysis between the JNQ score and each questionnaire revealed negative correlations with the ACT score (r = 0.262) and Mini-AQLQ score (r = -0.453) and positive correlations with the ACQ score (r = 0.337) and PHQ-9 score (r = 0.539). All of these correlations were statistically significant. As a result of the comparative test, the DB and non-DB groups showed a significant difference in Mini-AQLQ (P = .023) and PHQ-9 (P = .003) scores. No significant difference was observed between ACT (P = .294) and ACQ (P = .177) scores. Conclusions: The JNQ validates DB in Japanese people with asthma and reflects the deterioration of asthma control, decreased quality of life, and depression. Using the JNQ, early diagnosis and therapeutic intervention (eg, breathing exercises and a psychosomatic approach) for DB in people with asthma may help suppress the severity of asthma in Japan.

Efficacy of second-line chemotherapy in patients with pulmonary large cell neuroendocrine carcinoma.

The efficacy of second-line chemotherapy in patients with pulmonary large cell neuroendocrine carcinoma (LCNEC) is unclear. This study aimed to evaluate the efficacy of second-line chemotherapy in patients with pulmonary LCNEC. We retrospectively reviewed patients with pulmonary LCNEC or possible LCNEC (pLCNEC) who received platinum-based chemotherapy as the first-line treatment. Among these patients, we evaluated the efficacy of second-line treatment by comparing patients with small cell lung cancer (SCLC group). Of the 61 patients with LCNEC or pLCNEC (LCNEC group) who received first-line chemotherapy, 39 patients were treated with second-line chemotherapy. Among the 39 patients, 61.5% received amrubicin monotherapy. The median progression-free survival (PFS) and overall survival (OS) in the LCNEC groups were 3.3 and 8.3 months, respectively. No significant differences in the PFS (hazard ratio [HR]: 0.924, 95% confidence interval [CI] 0.647-1.320; P = 0.664) and OS (HR: 0.926; 95% CI 0.648-1.321; P = 0.670) were observed between the LCNEC and SCLC groups. In patients treated with amrubicin, the PFS (P = 0.964) and OS (P = 0.544) were not different between both the groups. Second-line chemotherapy, including amrubicin, may be considered as a treatment option for patients with pulmonary LCNEC.

Concordance of ALK fusion gene-rearrangement between immunohistochemistry and next-generation sequencing.

BACKGROUND: Although various companion diagnostic tests of ALK fusion gene-rearrangement are approved, few reports have assessed the concordance of ALK fusion gene-rearrangement in two companion diagnostic tests: next-generation sequencing (NGS) testing and immunohistochemistry (IHC). METHODS: The samples evaluated for gene alterations using NGS testing between May 2019 and November 2021 were included in this study. The inclusion criteria were as follows: samples were diagnosed with non-small cell lung cancer; the results of the NGS analysis were informative; and samples had residual specimens for IHC. We performed IHC on the residual specimens and retrospectively collected sample characteristics from medical records. RESULTS: A total of 185 samples were analyzed using NGS. Twenty-six samples were excluded because of failure to analyze gene alterations using NGS, no residual samples, and inadequate IHC. We analyzed 159 samples. The major histological type was adenocarcinoma (115 samples). The number of surgical and transbronchial lung biopsy specimens was 59 and 56, respectively. ALK fusion gene-rearrangement was detected in four samples using NGS, and five were detected using IHC. The sensitivity and specificity of IHC referred to by NGS were 75.0% and 98.7%, respectively. The concordance rate between IHC and NGS was 98.1%. ALK rearrangement was detected in two patients using IHC but not using NGS. In addition, ALK rearrangement was detected in one patient using NGS but not using IHC. CONCLUSION: Our results suggest that IHC and NGS might be complementary tests. In patients suspected of harboring ALK fusion gene-rearrangement, it should be analyzed using another diagnostic method.

Relationship between patterns of immunohistochemical conventional neuroendocrine markers and efficacy of immune check point inhibitors in patients with extensive disease small cell lung cancer.

BACKGROUND: Which patients benefit from the addition of immune checkpoint inhibitors (ICIs) to chemotherapy for small cell lung cancer (SCLC) remains unclear. There have been few reports on the efficacy of ICIs based on conventional immunohistochemical neuroendocrine (NE) markers (synaptophysin, chromogranin A, and neural cell adhesion molecule [NCAM]). In the present study, we aimed to analyze the relationship between the expression of immunohistochemical NE markers and the efficacy of ICIs in patients with extensive disease (ED)-SCLC, to assess whether conventional NE markers are predictive of ICIs. METHODS: Patients with untreated ED-SCLC who received first-line therapy at the Shizuoka Cancer Center between November 2002 and July 2021 were retrospectively reviewed. We evaluated the efficacy of first-line chemotherapy according to the expression status of each immunohistochemical NE marker in patients treated with ICI plus chemotherapy (ICI-chemo group) and with chemotherapy alone (chemo group). RESULTS: A total of 227 patients were included in the ICI-chemo and chemo groups, respectively. The progression-free survival (PFS) tended to be better in patients in the ICI-chemo group than those treated with chemotherapy alone in patients with NE marker-positive SCLC. In particular, it was statistically significant in patients with chromogranin A-positive SCLC (p = 0.036). In patients with NE marker-negative SCLC, no significant differences were observed in PFS between the two groups. There were no significant differences in overall survival (OS), regardless of the expression of any conventional NE marker. CONCLUSION: Our study suggests that the efficacy of ICIs in addition to chemotherapy may be poor in patients with NE marker-negative SCLC.

Different effects of crizotinib treatment in two non-small cell lung cancer patients with SDC4::ROS1 fusion variants.

The possibility of stratifying patients according to differences in ROS proto-oncogene 1 (ROS1) fusion partners has been discussed. This study aimed to clarify the clinicopathological differences between two SDC4::ROS1 positive NSCLC cases who had different responses to crizotinib. Cytology and pathology samples from two NSCLC cases with SDC4::ROS1 who were diagnosed and treated with crizotinib at Nihon University Itabashi Hospital were obtained. Case 1 has been well-controlled with crizotinib for over 5 years, but case 2 was worse and overall survival was 19 months. Sequencing analysis of ROS1 fusion genes was performed by reverse-transcription-PCR and Sanger's sequencing methods. In addition, thyroid transcription factor (TTF)-1, ROS-1, Ki67, and phosphorylated extracellular signal-regulated kinase (pERK)1/2 expression were investigated using immunohistochemistry. Sequencing analysis showed SDC4 exon2::ROS1 exon 32 (exon33 deleted) in case 1, and coexistence of SDC4 exon2::ROS1 exon 34 and SDC4 exon2::ROS1 exon35 in case 2. The Ki67 index was not different, but ROS1 and pERK1/2 expression levels tended to be higher in the tumor cells of case 2 than in case 1. Therapeutic response to crizotinib and patients' prognosis in ROS1 rearranged NSCLC may be related to the activation of ROS1 signaling, depending on ROS1 and pERK1/2 overexpression status, even if the ROS1 fusion partner is the same.

Fusobacterium nucleatum putatively affects the alveoli by disrupting the alveolar epithelial cell tight junction, enlarging the alveolar space, and increasing paracellular permeability.

Fusobacterium nucleatum (Fn) is abundant in the human oral cavity and has been associated with periodontal disease, which in-turn has been linked to respiratory disease development. Tight junctions (TJs) line the airway and alveoli surfaces serving as a first line of defense against multiple pathogens. Fn has already been linked to respiratory diseases, however, how Fn affects the alveolar TJ was not fully elucidated. Here, we designed and analyzed a TJ network, grew Fn cells and inoculated it in vitro (16HBE and primary cells) and in vivo (mice lung), measured transepithelial electrical resistance, performed RT-PCR, checked for in vitro cell and mice lung permeability, and determined air space size through morphometric measurements. We found that Fn can potentially affect TJs proteins that are directly exposed to the alveolar surface. Additionally, Fn could possibly cause neutrophil accumulation and an increase in alveolar space. Moreover, Fn putatively may cause an increase in paracellular permeability in the alveoli.

A Changing Anti-Neutrophil Cytoplasmic Antibody Profile in a Patient With a Diagnosis of Eosinophilic Granulomatosis With Polyangiitis.

This report describes a hitherto unique case of eosinophilic granulomatosis with polyangiitis (EGPA), a subtype of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. The patient was an 81-year-old man whose clinical course involved notable changes in the ANCA profile, specifically a transition from positive proteinase 3 (PR3)-ANCA to myeloperoxidase (MPO)-ANCA, followed by simultaneous positivity for both. The patient's medical history included bronchial asthma, allergic rhinitis, sinusitis, and multiple comorbidities. Despite being initially PR3-ANCA-positive, subsequent admissions demonstrated MPO-ANCA positivity along with eosinophilic manifestations, highlighting the complexity of diagnosis of EGPA. Diagnostic evaluation included imaging, serological markers, and clinical symptoms, which collectively supported the classification of EGPA. Notably, this case challenges the conventional diagnostic paradigms and emphasizes the evolving nature of ANCA profiles in vasculitis. The shift in ANCA profile prompted a reevaluation of the patient's diagnosis and treatment strategy. This case underscores the importance of considering fluctuations in ANCA in patients with a diagnosis of EGPA, management decisions, and potential implications for disease progression. Further research is warranted to elucidate the mechanisms underlying changes in ANCA and their clinical significance in vasculitis.

Anti-UBE2T antibody: A novel biomarker of progressive-fibrosing interstitial lung disease.

BACKGROUND: Anti-fibrotic therapy has demonstrated efficacy against progressive-fibrosing interstitial lung disease (PF-ILD); therefore, identifying disease behavior before progression has become a priority. As autoimmunity is implicated in the pathogenesis of various ILDs, this study explored circulating biomarkers that could predict the chronic progressive behavior of ILDs. METHODS: A single-center retrospective cohort study was conducted. Circulating autoantibodies in patients with ILD were screened using microarray analysis to identify candidate biomarkers. An enzyme-linked immunosorbent assay was performed with a larger sample set for the quantification of antibodies. After 2 years of follow-up, ILDs were reclassified as PF or non-PF. The relationship between the participants' autoantibody levels measured at enrolment and final diagnosis of PF-ILD was determined. RESULTS: In total, 61 healthy participants and 66 patients with ILDs were enrolled. Anti-ubiquitin-conjugating enzyme E2T (UBE2T) antibody was detected as a candidate biomarker. Anti-UBE2T antibody levels were elevated in patients with idiopathic pulmonary fibrosis (IPF). After following up on the study participants for 2 years, anti-UBE2T levels measured at enrolment significantly correlated with the new PF-ILD diagnosis. Immunohistochemical staining of normal lung tissues revealed sparsely located UBE2T in the bronchiole epithelium and macrophages, whereas IPF lung tissues showed robust expression in the epithelial lining of honeycomb structures. CONCLUSION: To our knowledge, this is the first report to describe an anti-UBE2T antibody, a new biomarker that is significantly elevated in patients with ILD who present future disease progression.

Continuous vs. Fixed 2-year Duration Immune Checkpoint Inhibitor Treatment of Patients With Non-Small Cell Lung Cancer: A Single Institution Database Analysis.

INTRODUCTION/BACKGROUND: The proper duration of immune checkpoint inhibitor (ICI) treatment for patients with advanced non-small cell lung cancer (NSCLC) remains unclear. Previously, sponsor-initiated clinical trials have more often used either a maximum 2-year fixed duration of ICI treatment or continuous treatment until documented disease progression. The study aimed to evaluate the association between ICI treatment duration (2-year fixed or continuous) and prognosis in patients with advanced NSCLC. PATIENTS AND METHODS: The medical records of 425 patients with NSCLC who received ICI before August 31, 2019 were retrospectively reviewed. RESULTS: No differences in time to treatment failure > 24 months (TTF-24) were detected between patients who underwent ICI treatment for > 2 years and patients who stopped ICI treatment at 2 years. Treatment-related adverse events tended to be higher in the patients with ICI treatment > 2 years. CONCLUSION: ICI treatment > 2 years did not significantly prolong the TTF compared with ICI treatment = 2 years, but it did increase the incidence of treatment-related adverse events.

Retrospective Analysis of the Incidence of Drug-Induced Interstitial Lung Disease by Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors and Survival in Patients Aged 75 Years or Older with Lung Cancer.

Introduction: To date, the appropriate epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) for patients aged ≥75 years with advanced EGFR mutation-positive, nonsmall cell lung cancer remain unknown. Methods: This study included a total of 89 patients aged ≥75 years who were diagnosed with EGFR mutation-positive, nonsmall cell lung cancer and treated with EGFR-TKIs at the Tokyo Metropolitan Geriatric Hospital and Nihon University ITABASHI Hospital from 2009 to 2020. The patients were classified into five groups based on their treatment: gefitinib (n = 23), erlotinib (n = 4), afatinib (n = 3), first-line osimertinib (n = 23), and TKI to TKI (n = 36). The efficacy and safety of each EGFR-TKI were analyzed. Results: No significant differences in the overall survival and progression-free survival were observed among the groups. However, a significantly higher incidence of drug-induced interstitial lung disease (ILD) was detected with osimertinib than with the first-generation EGFR-TKIs (p = 0.008). Conclusions: In older patients with EGFR mutation-positive lung cancer, the incidence of drug-induced ILD was significantly increased during osimertinib treatment. This outcome should be noted when treating older patients with osimertinib who may not always want to live longer but want to live better.

Anti-synthetase syndrome-associated interstitial lung disease possibly caused by atezolizumab in a patient with lung adenocarcinoma: a case report.

BACKGROUND: Anti-aminoacyl-tRNA synthetase (ARS) antibody-positive patients present with a variety of symptoms, including interstitial lung disease (ILD), which is termed anti-synthetase syndrome (ASS). But it is rare that ASS-ILD is considered an immune-related adverse event after the use of immune checkpoint inhibitors (ICIs). CASE PRESENTATION: A 47-year-old male with advanced lung adenocarcinoma was treated with platinum and ICI combination immunotherapy and was followed up as an outpatient. Nine months after the start of treatment, he developed a fever and cough, and imaging findings showed lung consolidations in the bilateral lower lung fields. The patient was positive for anti- ARS antibodies and was considered to have developed ASS-ILD due to ICIs remitted with steroid therapy. The patient was found to be positive for anti-ARS antibodies before ICI administration, and the antibody titer was elevated compared to that before ICI administration. CONCLUSIONS: The examination of anti-ARS antibodies pior to the administration of ICIs may be useful in predicting the development of ASS-ILD.

Idiopathic Central Alveolar Hypoventilation wherein Sleep Disordered Breathing Was Considered Well-controlled by the Continuous Positive Airway Pressure Tracking System but Not Controlled by Polysomnography.

A 54-year-old man whose awake percutaneous arterial oxygen saturation (SpO2) was 94% was diagnosed with obstructive sleep apnea by polysomnography (PSG). His apnea-hypopnea index (AHI) was 138.8 (AI: 4.7 and HI: 134.1), so he was treated with continuous positive airway pressure (CPAP), and his condition was considered well-controlled by the CPAP tracking system (AHI=3.4), with improvement seen in his symptoms when he left our hospital. However, he returned to our hospital 4 years later with recurrent sleepiness and hypercapnia despite the well-controlled status (AHI=3.8) according to the tracking system. His hypercapnia improved following voluntary hyperventilation. Idiopathic central alveolar hypoventilation was diagnosed, with the AHI considered to be well-controlled by the CPAP tracking system but not at all according to PSG.

Platypnoea-orthodeoxia syndrome affects nocturnal oxygen desaturation: A case report.

A woman in her late 20s who had received an implantable cardioverter defibrillator in childhood for ventricular arrhythmia was diagnosed with severe obstructive sleep apnoea (apnoea-hypopnoea index, 77.1/h), and she began continuous positive airway pressure treatment. Before initiating this treatment, she had moderate hypoxaemia of unknown cause. She was admitted for adjustment of the position of her implantable cardioverter defibrillator, which had caused purple discoloration and ulceration of the overlying skin. On admission, she had dyspnoea and her arterial oxygen saturation by pulse oximetry significantly decreased while sitting. This led to detection of a patent foramen ovale and a right-to-left shunt while sitting. We diagnosed platypnoea-orthodeoxia syndrome with an atrial septal defect. Atrial septal defects should be suspected in hypoxic patients with obstructive sleep apnoea.

Chronic Hepatitis C: Acute Exacerbation and Alanine Aminotransferase Flare.

The hepatitis C virus (HCV) causes acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma, as well as extrahepatic manifestations such as malignant lymphoma. Currently, direct-acting antiviral agents (DAAs) against HCV infection can lead to a sustained virological response (SVR) in almost all HCV-infected patients. In this review article, we discuss acute exacerbation and alanine aminotransferase (ALT) flare in patients with chronic HCV infection. Although acute liver failure caused by HCV infection is rare, careful attention should be paid to the cases with ALT elevation during the natural course of chronic HCV infection. HCV genotype 2 infection, the use of rituximab, and a higher dose of corticosteroid are factors associated with HCV acute exacerbation and ALT flare. Treatment regimens for cancer have been interrupted or changed due to ALT flare due to HCV infection in some patients undergoing chemotherapy for cancer. The pathogenesis of HCV acute exacerbation and ALT flare could involve cellular as well as humoral immune responses. In the DAA era, the earlier introduction of DAAs may prevent chronic HCV-infected patients with acute exacerbation and ALT flare from developing into a more severe form, although DAAs may not be effective for all of them.

Efficacy and safety of carboplatin and etoposide in older extensive-stage small-cell lung cancer patients with a poor performance status.

Carboplatin plus etoposide is a standard treatment for older extensive-stage small-cell lung cancer (ES-SCLC) patients with performance status (PS) 2. However, older patients often exhibit poor PS (3, 4), and the treatment effect in them is poorly understood. To determine the therapeutic efficacy and safety of carboplatin plus etoposide therapy for this population, we retrospectively analyzed 63 patients with ES-SCLC with PS ≥2, aged ≥71 years, who had received first-line carboplatin plus etoposide therapy. We compared the treatment efficacy and safety in patients with baseline PS 2 versus those with PS 3-4. In the PS 2 (38 patients) and PS ≥3 (25 patients) groups, the overall response rate was 71.1% and 72.0%, median progression-free survival was 4.6 and 3.1 months, and overall survival was 7.7 and 5.1 months, respectively. PS improved to 0-1 post-treatment in 65.8% and 48.0% of the patients in the PS 2 and PS ≥3 groups, respectively. Patients with PS ≥3 showing improved PS had a progression-free survival of 6.1 months. A higher incidence of grade ≥3 decreased neutrophil counts, febrile neutropenia, and treatment-related death was observed in the PS ≥3 group. The progression-free survival of patients administered prophylactic granulocyte colony-stimulating factor (G-CSF) was 5.2 and 6.1 months in the PS2 and PS ≥3 groups. Overall, carboplatin plus etoposide therapy provided comparable tumor shrinkage, but shorter progression-free and overall survival in older ES-SCLC patients with PS ≥3 than in those with PS 2. Thus, supportive care, such as prophylactic G-CSF administration, may be necessary to ensure safety and survival.