Myofibroblast differentiation is a pivotal event in idiopathic pulmonary fibrosis (IPF) and is driven by TGF-β1-dependent PTEN destabilization; however, the intermediate regulators remain incompletely defined. We tested three lung fibroblast cell lines (one normal and two IPF-derived) and identified the phosphatidylinositol 3,4,5-trisphosphate-dependent Rac exchanger 2 (PREX2)-membrane-associated guanylate kinase inverted 2 (MAGI2) as a critical regulator of myofibroblast differentiation. Loss-of-function analysis of MAGI2 in normal human lung fibroblasts revealed a shift toward a myofibroblast phenotype characterized by abundant α-SMA expression. In vitro experiments revealed increased PREX2 expression and decreased MAGI2 expression in IPF-derived lung fibroblasts compared with those in normal lung fibroblasts. Consistent with this finding, in vivo experiments using bleomycin-induced murine pulmonary fibrosis revealed PREX2 upregulation in contrast to MAGI2 downregulation with the progression of lesions. Notably, PREX2 depletion in IPF-derived cells enhanced MAGI2 expression, mitigating TGF-β1-induced α-SMA expression. Conversely, PREX2 overexpression promoted myofibroblast differentiation, as evidenced by MAGI2 downregulation followed by marked α-SMA expression. The PREX2-targeting suppressive miR-338-3p upregulated MAGI2 expression in vitro and ameliorated bleomycin-induced murine pulmonary fibrosis in vivo. Immunohistochemical staining of PREX2 on lung samples obtained from patients with IPF delineated that PREX2 was exclusively expressed in the fibroblastic foci of IPF-affected lungs. Fluorescence immunostaining revealed PREX2 colocalization with α-SMA in myofibroblasts within fibroblastic foci, corroborating our hypothesis. These findings suggest that MAGI2 acts as a negative regulator of myofibroblast differentiation by stabilizing PTEN, whereas PREX2 is aberrantly expressed in the fibrotic milieu, negatively modulating MAGI2, thereby accelerating pulmonary fibrosis.

Background Antifibrotic therapies slow functional decline and improve survival in patients with idiopathic pulmonary fibrosis (IPF). Although early initiation is generally recommended, the optimal timing of treatment in real-world clinical practice remains uncertain. In particular, the relationship between the interval from diagnosis to treatment initiation and overall survival (OS), as well as the clinical implications of physician-judged deferred initiation, have not been fully clarified. Methods This multicenter retrospective cohort study included 150 patients diagnosed with IPF between April 2021 and March 2023 who received antifibrotic therapy. Treatment timing was evaluated using two definitions: 1) objectively defined intervals from diagnosis of IPF to treatment initiation (0–180, 181–364, and ≥ 365 days); and 2) physician-judged deferred initiation documented in medical records, defined as a clinician‑guided postponement based on clinical, patient‑related, or contextual considerations. The primary endpoint was OS. Landmark analyses were performed at 180 and 365 days to reduce immortal time bias. Survival outcomes were analyzed using the Kaplan–Meier method and Cox proportional hazards regression models. Multivariable analyses were used to adjust for relevant clinical covariates. In addition, reasons for delayed treatment initiation were examined. Results Among the 150 patients, longer diagnosis-to-treatment intervals were associated with longer OS in the landmark analyses. In contrast, patients with physician-judged deferred initiation showed no significant difference in OS (log-rank p = 0.164), although physician-judged deferred initiation was independently associated with OS in the multivariable analysis. In the multivariable analysis, older age, lower percent predicted forced vital capacity (%forced vital capacity), and a longer interval from referral to IPF diagnosis were also independently associated with OS. The most common reasons for delayed initiation included minimal or stable symptoms, concerns regarding adverse effects, and diagnostic uncertainty. Conclusions Physician‑judged deferred initiation was independently associated with OS, likely reflecting underlying disease activity and clinical risk stratification rather than a direct causal effect of postponing therapy. These findings underscore the limitations of evaluating treatment timing solely by elapsed time and emphasize the importance of early diagnosis, timely referral to specialized centers, and individualized clinical decision-making in the management of IPF. Clinical trial registration Not applicable.

Immunoglobulin light chain (AL) amyloidosis is characterized by the systemic deposition of light-chain-derived amyloids. Immunoglobulin M (IgM)-associated AL amyloidosis is extremely rare and clinically distinct. A 70-year-old man presented with dyspnea, bilateral pleural effusion, and mediastinal lymphadenopathy on computed tomography (CT). Amyloid was detected in a pleural effusion cell block and confirmed via an axillary lymph node biopsy. Serum studies and bone marrow findings supported IgM-λ AL amyloidosis associated with Waldenström macroglobulinemia/lymphoplasmacytic lymphoma. First-line therapy failed, but second-line therapy reduced pleural effusion, avoiding thoracentesis for one year. A pleural effusion cell block analysis enabled rapid diagnosis with minimally invasive exploration.

BACKGROUND:Long-term maintenance steroid therapy (MST) is often necessary for repeated relapses of chronic eosinophilic pneumonia (CEP). Because relapse does not indicate a worse prognosis, determining the optimal steroid dose to avoid overtreatment presents a clinical challenge. Our primary objective was to evaluate the optimal MST dose to prevent repeated relapses, and the secondary objectives included identifying serum eosinophil count at relapse and background factors of relapse. METHODS:A multicentre retrospective study was conducted on patients with steroid-treated CEP. Background characteristics were compared between the non-relapse and relapse groups. The optimal MST dose was determined based on dose at relapse and the final relapse prevention dose. Additionally, serum eosinophil count at relapse was assessed. RESULTS:A total of 79 patients were included, with 44 in the non-relapse group and 35 in the relapse group. The prednisolone doses required to achieve relapse-free rates of 50% (ED50) were 7.2 mg (95% CI, 4.6 to 23.6). The median serum eosinophil count at relapse was 1125 /µL (IQR, 735-2108). No clinically significant background factors were identified between the non-relapse and relapse groups. CONCLUSION:Our study demonstrated that a prednisolone dose of 7.2 mg achieved a 50% relapse-free rate in the relapse group. Based on these findings, we encourage clinicians to evaluate individual minimum effective steroid doses.

Pembrolizumab is an immune checkpoint inhibitor (ICI) of programmed cell death-1 category, used for treating various types of cancer. ICIs can sometimes result in immune-related adverse events. Allergic bronchopulmonary mycosis (ABPM) induced by ICI has rarely been reported. We hereby report the case of an 83-year-old woman who experienced non-Aspergillus ABPM with eosinophilia induced by pembrolizumab that had been prescribed for treating bladder cancer. Steroid monotherapy with prednisone was successful and pembrolizumab could be resumed. Through the present case report, we urge the clinicians to be aware of the potential risk of ABPM as a T-helper type 2-associated immune-related adverse event.

In pulmonary hypertension (PH) associated with chronic lung disease (CLD), identifying patients who would benefit from pulmonary vasodilators is a significant clinical challenge because the presence of PH is associated with poorer survival. This study evaluated the severity of pulmonary circulation impairment in patients with CLD-PH using pulmonary perfusion single-photon emission computed tomography/computed tomography (SPECT/CT). This single-center, observational study enrolled patients with CLD-PH who had a mean pulmonary arterial pressure (PAP) ≥ 25 mmHg, as confirmed by right heart catheterization. The primary outcome was to measure the percentage of pulmonary perfusion defect (%PPD), calculated by dividing the perfusion defect volume from perfusion SPECT images by the lung volume from CT scan images. The secondary outcome was to assess the correlation between %PPD and baseline characteristics. The median %PPD was 52.4% (interquartile range, 42.5%-72.3%) in 22 patients. In multivariate linear regression analysis, both forced vital capacity (β = 0.58, p = 0.008) and mean PAP (β = 0.68, p = 0.001) were significantly correlated with %PPD. In conclusion, significant correlation between mean PAP and %PPD in patients with CLD-PH was observed. This noninvasive assessment of %PPD may be useful for evaluating the severity of pulmonary circulation impairment in CLD-PH.

Background: Malignant pleural effusion (MPE) remains a negative prognostic factor in non-small cell lung cancer (NSCLC), even after the emergence of immune checkpoint inhibitors. Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of MPE. Bevacizumab, a humanized monoclonal antibody against VEGF, is a key agent for patients who develop MPE. However, it is unclear whether MPE is a poor prognostic factor in patients with advanced non-squamous NSCLC receiving treatment with the atezolizumab plus bevacizumab, carboplatin, and paclitaxel (ABCP) regimen. Moreover, the effect of ABCP on MPE control is unknown. This study aimed to elucidate the efficacy and safety of ABCP for nonsquamous NSCLC patients with MPE. Methods: We retrospectively analyzed consecutive patients with advanced non-squamous NSCLC who received treatment with ABCP (January 2019-September 2023). Patients were divided into two groups (nonMPE and MPE), and treatment outcomes were compared. In the MPE group, treatment efficacy for MPE control and toxicity were evaluated. Results: Of the 46 patients enrolled, 17 and 29 were included in the non-MPE and MPE groups, respectively. The objective response and disease control rates were not significantly different between the non-MPE and MPE groups (76.5% vs. 51.7%, P=0.13; 88.2% vs. 82.8%, P>0.99; respectively). Similarly, the median progression-free survival and median overall survival were not significantly different (9.9 vs. 10.1 months, P=0.87; 16.0 vs. 19.9 months, P=0.87, respectively). In the MPE group, 25 patients (86.2%) achieved MPE control lasting >8 weeks from the initiation of treatment with ABCP; the median progression-free survival without an unequivocal increase in MPE was 15.0 months. The incidence rates of grade >= 3 non-immune- and immune-related adverse events were 83% and 17%, respectively. There was no treatment-related death. Conclusions: The ABCP regimen may be a promising treatment option for non-squamous NSCLC patients with MPE.

Sarcoidosis is a systemic granulomatous disease; however, the incidence of bone sarcoidosis is relatively rare. The short tubular bones of the hands and feet are most frequently affected, while the vertebrae and the pelvic bones are rarely involved. We hereby report a rare case of multiple bone sarcoidosis involving the vertebrae and pelvic bones, evaluated before and after steroid therapy using two different imaging modalities: bone scintigraphy and A 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT). FDG-PET/CT is effective for detecting bone lesions; however, whole-body imaging is recommended to detect the short tubular bones of the hands and feet, which are most frequently affected.

Purpose:Osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is the standard treatment for patients with non-small cell lung cancer harboring EGFR mutations. Although the frequency of osimertinib-induced interstitial lung disease (osi-ILD) is high, the optimal cancer treatment after osi-ILD has not been established. This time, we focused on the safety and efficacy of gefitinib following osi-ILD. Case Presentation:We experienced six cases (five women and one man; median age: 74 years) in which gefitinib was administered after osi-ILD. All six cases had grade 2 or higher osi-ILD and required steroid treatment. The computed tomography imaging pattern of osi-ILD revealed organizing pneumonia in three cases, diffuse alveolar damage in two cases, and hypersensitivity pneumonia in one case. Eastern Cooperative Oncology Group performance status was 1 in four cases, 2 in one case, and 3 in one case. EGFR mutation status was exon 19 deletion in two cases and exon 21 L858R in four cases. Only one patient experienced recurrence of ILD after receiving gefitinib. The best response to gefitinib was partial response in two cases and stable disease in three cases; one case was not evaluable. The median progression-free survival after treatment with gefitinib was 190 days (95% confidence interval: 33-328). Conclusion:The treatment with gefitinib after the development of osi-ILD was safe and effective. Gefitinib may be a promising option for patients who recovered from severe osi-ILD.

Background: Long-term maintenance steroid therapy (MST) is frequently required for repeated relapses of cryptogenic organizing pneumonia (COP); however, the optimal minimal dose has not been clarified. Therefore, this study evaluated the minimal MST dose required to prevent repeated relapses and identify relapse predictors. Methods: We retrospectively reviewed the medical records of patients with steroid-treated COP and compared background factors between the non-relapse and relapse groups. We also reviewed the treatment course in the relapse group and determined the minimal effective steroid dose based on the MST dose at relapse events and the current relapse prevention dose. Results: In total, 48 patients were identified, including 27 (56%) in the non-relapse group and 21 (44%) in the relapse group. Receiver operating characteristic curve analysis identified prednisolone at 5 mg/day as the optimal cut-off value in the relapse group. Relapse-free time in patients with relapsed COP was significantly longer in the MST dose >= 5 mg/day group than in the <5 mg/day group (log-rank P = 0.003; hazard ratio, 0.19; 95% confidence interval [CI], 0.04-0.60). Multivariate logistic regression analysis demonstrated that a high eosinophil percentage and CD4/CD8 ratio in bronchoalveolar lavage fluid (BALF) were predictors of relapse (odds ratio [OR], 1.12; 95% CI, 1.02-1.23; P = 0.008 and OR, 3.87; 95% CI, 1.29-11.6; P = 0.008, respectively). Conclusions: Our results indicate that 5 mg/day of prednisolone may be the minimal effective dose for preventing repeated relapses, and a high BALF eosinophil percentage and CD4/CD8 ratio are independent predictors of relapse.

Thyroid transcription factor-1 (TTF-1) is expressed in 60-80% of lung adenocarcinoma and is used in pathological diagnosis. Previous retrospective studies suggested that TTF-1-negative expression is a poor prognostic factor in patients with lung adenocarcinoma treated with immune checkpoint inhibitors (ICIs) monotherapy. However, the efficacy of ICIs plus chemotherapy for TTF-1-negative lung cancer patients remains elusive.

Background: Rechallenge with platinum-combination chemotherapy in patients with advanced non-small cell lung cancer (NSCLC) after disease progression on platinum-combination chemotherapy occasionally leads to a favorable response. The efficacy and safety of platinum-combination chemotherapy with or without immune-check-point inhibitor (ICI) for patients with recurrent NSCLC after surgery followed by adjuvant platinum-doublet chemotherapy remains uncertain.Methods: Patients who relapsed after surgery plus adjuvant platinum-doublet chemo-therapy and received platinum-combination chemotherapy with or without ICI between April 2011 and March 2021 at four Nippon Medical School hospitals were retrospectively analyzed.Results: Among 177 patients who received adjuvant platinum-doublet chemotherapy after surgery, a total of 30 patients who received platinum-combination rechemotherapy with or without ICI after relapse were included in this study. Seven patients received ICI-combined chemotherapy. The median disease-free survival (DFS) after surgery was 13.6 months. The objective response rate and disease-control rate were 46.7% and 80.0%, respectively. The median progression-free survival and overall survival were 10.2 and 37.5 months, respectively. Patients with longer DFS (=12 months) had a better prognosis than others. The most common grade =3 toxicity associated with this treatment was neutropenia (33%). Grade =3 immune-related adverse events were pneumonitis (14%) and colitis (14%). Treatment-related deaths did not occur in this study.Conclusion: Platinum-combination chemotherapy with or without ICI for patients with postoperative recurrent NSCLC who previously received adjuvant platinum-doublet chemotherapy was effective and safe. In particular, this therapy may be prom-ising for patients with longer DFS.

Background:Thyroid transcription factor-1 (TTF-1) is expressed in approximately 70% of lung adenocarcinomas and is one of the most reliable makers to distinguish primary lung adenocarcinoma from metastatic disease. TTF-1-negative status is a poor prognostic factor, and TTF-1-negative lung adenocarcinoma is associated with poor efficacy of immune checkpoint inhibitor (ICI) monotherapy. However, the relationship between TTF-1 expression and the efficacy of ICI plus chemotherapy is still unclear.Methods:We performed a retrospective analysis of 129 consecutive patients with advanced non-squamous non-small cell lung cancer (NS-NSCLC) treated with ICI monotherapy or ICI plus chemotherapy between January 2016 and December 2021. The expression of programmed death ligand-1 (PD-L1) and TTF-1 was also determined in cases for which no previous data were available. We then evaluated the association between TTF-1 expression status and treatment efficacy.Results:Of the 129 cases, 33 were TTF-1-negative and 96 were positive. In the ICI monotherapy group (N=70), progression-free survival (PFS) was not significantly different between TTF-1-positive and negative patients (median 3.6 vs. 3.8 months, P=0.27); however, in patients with wild-type epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), a trend for worse PFS was observed in TTF-1-negative cases compared with those that were TTF-1-positive (median 3.8 vs. 4.5 months, P=0.088). Moreover, long-term efficacy of ICI monotherapy (>2 years) was not observed in the TTF-1-negative group. TTF-1-negative patients tended to have worse overall survival (OS) than TTF-1-positive patients (median 15.6 vs. 19.5 months, P=0.13). In the ICI plus chemotherapy group (N=59), TTF-1-negative patients tended to have better PFS and similar OS compared with TTF-1-positive patients (median 9.9 vs. 9.6 months, P=0.14; median 32.3 vs. 18.9 months, P=0.78). Long-term efficacy was generally observed in TTF-1-negative patients treated with atezolizumab plus bevacizumab plus carboplatin plus paclitaxel (ABCP) (median PFS 22.5 months, median OS not reached).Conclusions:ICI monotherapy is generally less efficacious in TTF-1-negative NS-NSCLC patients, and clinicians should consider ICI plus chemotherapy in these cases. Our study suggests that ABCP is an optimal regimen for TTF-1-negative NS-NSCLC.

Background: Primary pulmonary choriocarcinoma (PPC) is a rare malignancy, and only 41 PPC cases have been reported in males up to 2021. Due to its rarity, no standardized treatments for PPC have been established. Cytotoxic chemotherapy has limited efficacy, and the prognosis of advanced PPC is notably poor. Immune checkpoint inhibitors (ICIs) are expected to provide long-term survival for PPC patients, but only a few cases have been reported. The optimal treatment for PPC has not been determined.Case Description: Here, we report a 72-year-old male with post-surgery relapsed PPC, presenting with multiple pulmonary nodules and an intracardiac mass. The OncomineTM Dx target test showed no mutation of cancer-relevant genes, and programmed death-ligand 1 (PD-L1) expression was negative (0%) in the 22C3 assay. He received a combination of carboplatin, paclitaxel, nivolumab, and ipilimumab which is widely used as a first-line treatment for advanced non-small-cell lung cancer (NSCLC). Two months after treatment began, computed tomography (CT) showed multiple lung nodules and an intracardiac mass reduction, which has been sustained for 12 months. Grade 3 febrile neutropenia and grade 2 rash were observed, however, these adverse events were manageable. Conclusions: This is the first case of postoperative relapse PPC that has been successfully treated with the combination of chemotherapy, nivolumab, and ipilimumab. This therapy may be a promising option for advanced PPC.

Eosinophilic bronchiolitis is a disease concept reported in Japan in 2001, that presents with bronchiolitis accompanied by eosinophilia in the blood and lungs. In 2013, hypereosinophilic obliterative bronchiolitis, as a group of disease presenting with eosinophilic bronchiolitis, was proposed in France. The relationship between eosinophilic bronchiolitis and other eosinophil-related diseases has not been clarified. Herein, we report the case of a 56-year-old female patient with eosinophilic bronchiolitis without asthma, which developed into eosinophilic pneumonia. Treatment with oral prednisone improved the respiratory function. According to the clinicopathological findings in this case, eosinophilic bronchiolitis may be a different disease from asthma.

While high-level evidence is lacking, numerous retrospective studies have depicted the value of supplemental oxygen in idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases, and its use should be encouraged where necessary. The clinical course and survival of patients with IPF who have been introduced to oxygen therapy is still not fully understood. The objective of this study was to clarify overall survival, factors associated with prognosis, and causes of death in IPF patients after the start of oxygen therapy. This is a prospective cohort multicenter study, enrolling patients with IPF who started oxygen therapy at 19 hospitals with expertise in interstitial lung disease. Baseline clinical data at the start of oxygen therapy and 3-year follow-up data including death and cause of death were assessed. Factors associated with prognosis were analyzed using univariable and multivariable analyses. One hundred forty-seven eligible patients, of whom 86 (59%) were prescribed ambulatory oxygen therapy and 61 (41%) were prescribed long-term oxygen therapy, were recruited. Of them, 111 died (76%) during a median follow-up of 479 days. The median survival from the start of oxygen therapy was 537 ± 74 days. In the univariable analysis, low body mass index (BMI), low forced vital capacity (FVC), low diffusion capacity (DLCO), resting hypoxemia, short 6 min-walk distance, and high COPD assessment test (CAT) score were significantly associated with poor prognosis. Multivariable analysis revealed low BMI, low FVC, low DLCO, low minimum SpO2 on 6MWT, and high CAT score were independent factors for poor prognosis. The overall survival of IPF patients after starting oxygen therapy is about 1.5 years. In addition to pulmonary function tests, 6MWT and patient reported outcomes can be used to predict prognosis more accurately.Clinical Trial Registration: UMIN000009322.

背景．免疫チェックポイント阻害薬によるpseudo-progressionは非小細胞肺癌患者の約5%にみられるが，免疫チェックポイント阻害薬単剤における報告がほとんどである．今回，ニボルマブ＋イピリムマブ併用療法後に胸膜炎様のpseudo-progressionを認めた肺腺癌の1例を経験した．症例．70歳，男性．胸膜播種を伴う肺腺癌pT3N0M1a stage IVAに対し1次治療としてカルボプラチン＋ペメトレキセド＋ニボルマブ＋イピリムマブを投与した．投与後から発熱，呼吸困難，CRPの上昇，患側胸水の増加を認めた．胸水ドレナージを行い，セルブロック標本でCD4陽性T細胞を主体とした豊富なリンパ球の滲出を認めた．その後症状が軽快し，化学療法継続下で胸水の再貯留を認めていないことから，免疫関連有害事象ではなく，pseudo-progressionと診断した．結論．本症例はニボルマブ＋イピリムマブ併用療法後に胸膜炎様のpseudo-progressionを認めた肺癌における初めての報告である．免疫関連有害事象による胸膜炎との鑑別が重要である．

背景.免疫チェックポイント阻害薬による劇症1型糖尿病は稀な有害事象である.肺癌においては非小細胞肺癌での報告が散見される.今回,小細胞肺癌に対するデュルバルマブ投与後に劇症1型糖尿病を発症した症例を経験した.症例.71歳男性,Performance Status 1.糖尿病の既往歴なし.進展型小細胞肺癌cT4N3M1b stage IVAに対して,20XX年5月よりカルボプラチン+エトポシド+デュルバルマブ併用療法が開始された.Day 27より食欲不振,倦怠感が出現し,2コース目投与日(day 30)の検査で高血糖(761 mg/dl),尿ケトン陽性,尿中Cペプチド3.9 μg/日を認め,デュルバルマブによる劇症1型糖尿病と診断した.インスリン治療で血糖コントロールが得られた後に,カルボプラチン+エトポシド併用療法が3コース行われた.著明な治療効果が得られ,その後病状進行はみられていない.結論.小細胞肺癌に対するデュルバルマブ投与後の劇症1型糖尿病発症は稀であるが,緊急性のある免疫関連有害事象であり注意を要する.

Rationale: Black pleural effusion is a rare medical condition and a diagnostic marker. Pancreaticopleural fistula is one of the causes of black pleural effusion. Thus far, black pleural effusions caused by pancreaticopleural fistulae have mostly been reported in patients with alcohol-induced chronic pancreatitis. In this report, we present a case of black pleural effusion caused by a pancreaticopleural fistula associated with autoimmune pancreatitis. Patient concerns and diagnosis: A 59-year-old female without a history of alcohol drinking presented to our hospital with a chief complaint of dyspnea, as well as chest and back discomfort. She had left pleural effusion, and thoracentesis showed black pleural effusion. Computed tomography revealed the presence of encapsulated fluid from the pancreatic tail to the left pleural cavity, which was diagnosed as a pancreaticopleural fistula. It also showed diffuse pancreatic swelling. Serum testing showed a high IgG4 level (363 mg/dL). These findings led to the diagnosis of autoimmune pancreatitis. Interventions and outcome: The patient underwent endoscopic pancreatic sphincterotomy and pancreatic duct stent placement and received treatment with steroids. After treatment, there was no further accumulation of pleural effusion observed. Conclusion: This is the first report of black pleural effusion due to a pancreaticopleural fistula associated with autoimmune pancreatitis. The characteristic appearance of black pleural effusion may assist diagnosis. We report this case to emphasize that autoimmune pancreatitis can be a cause of black pleural effusion.

Background and Aims: Transthoracic echocardiography has a problem with sensitivity in detecting pulmonary hypertension associated with interstitial lung disease (PH-ILD).This study aimed to evaluate the correlation between %FVC/%DLco ratio and pulmonary hemodynamics in PH-ILD, compared with the echocardiographic tricuspid regurgitation peak gradient (TRPG).Methods: We conducted a retrospective study for patients with ILD who underwent a right heart catheterization in Nippon Medical School Hospital from April 2017 to March 2020.We statistically evaluated the correlations between % FEV/%DLco, TRPG and pulmonary hemodynamics such as systolic pulmonary artery pressure (sPAP) and mean pulmonary artery pressure (mPAP).We determined the optimal cut-off value of %FVC/%DLco and TRPG for PH-ILD defined as mPAP ≧25 mmHg.Results: A total of 15 patients were enrolled.The median % FEV/%DLco was 2.21 (IQR, 1.66-3.53).The median TRPG was 51.3 (IQR, 32.0-70.9)mmHg.The median sPAP and mPAP were 59 (IQR, 27-70) and 33 (IQR, 17-42) mmHg.% FVC/%DLco was significantly correlated with sPAP (r = 0.68, p < 0.01) and mPAP (r = 0.65, p < 0.01).TRPG was significantly correlated with sPAP (r = 0.84, p< 0.01) and mPAP (r = 0.79, p < 0.01).At the cut off value of 1.8 for %FVC/%DLco, the sensitivity and specificity were 9/9 (100%) and 9/11 (82%), respectively.At the cut off value of 50mmHg for TRPG, the sensitivity and specificity were 8/9 (89%) and 8/8 (100%), respectively.Conclusions: Our results indicate that %FEV/%DLco ratio is effective in detecting PH-ILD as well as echocardiography.