Diagnosis of Synchronous Primary Lung Cancers Using EBUS‐TBNA and BDBD‐Assisted Transbronchial Biopsy During a Single Bronchoscopic Procedure: A Case Report

ABSTRACT

Histopathological confirmation is essential to determine the optimal treatment strategy for patients with multiple pulmonary lesions. We report a case of synchronous small cell lung cancer (SCLC) and non‐small cell lung cancer (NSCLC) diagnosed during the same bronchoscopic session using endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) and balloon dilation for bronchoscope delivery (BDBD) technique. A 70‐year‐old man with a history of gastric cancer presented with mediastinal lymphadenopathy and a nodule in the right upper lobe. EBUS‐TBNA confirmed SCLC in the mediastinal lymph nodes. For the peripheral pulmonary lesion, BDBD enabled further advancement of the thin bronchoscope, allowing direct visualization and biopsy with standard forceps, which confirmed NSCLC. No procedure‐related complications occurred. This case suggests that combining EBUS‐TBNA with BDBD facilitates the accurate diagnosis of multiple pulmonary lesions during the same bronchoscopic session.

A 70‐year‐old man with mediastinal lymphadenopathy and a right upper lobe nodule underwent simultaneous bronchoscopic evaluation using EBUS‐TBNA and balloon dilation for bronchoscope delivery (BDBD). EBUS‐TBNA confirmed small cell lung cancer in the mediastinal nodes, whereas BDBD enabled additional peripheral advancement of the thin bronchoscope from B³a to B³ai, resulting in direct visualization of the target lesion and biopsy confirming non‐small cell lung cancer.

1. Introduction

The diagnosis and management of multiple primary lung cancers require accurate histopathological confirmation of each lesion to determine the optimal treatment strategy. In patients with multiple primary malignancies or a history of cancer, pulmonary metastases and mediastinal or hilar lymph node metastases must be carefully differentiated from newly developed primary lung cancers. In such cases, establishing a definitive diagnosis using minimally invasive bronchoscopy is essential. To support appropriate patient decision‐making, histological confirmation should be performed using various bronchoscopic devices.

We encountered a case in which synchronous double primary lung cancers, namely small cell lung cancer (SCLC) and non‐small cell lung cancer (NSCLC), were successfully diagnosed during the same bronchoscopic session using endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) and balloon dilation for bronchoscope delivery (BDBD) technique [1], respectively. We report this case because reports on clinical experience with BDBD are limited [2, 3, 4].

2. Case Report

A 70‐year‐old man with a history of advanced gastric cancer was referred to our department for bronchoscopy owing to abnormal chest imaging findings, including pulmonary nodules and mediastinal lymphadenopathy. Computed tomography (CT) scans obtained at the referring hospital revealed rapid enlargement of the mediastinal lymph nodes, whereas the nodule in the right upper lobe demonstrated relatively slow growth (Figure 1A). Bronchoscopy was performed to establish a definitive diagnosis, with differential diagnoses such as metastatic disease from prior malignancies and newly developed primary lung cancer.

FIGURE 1.

(A) Computed tomography (CT) scans obtained at the referring hospital revealing rapid enlargement of the mediastinal lymph nodes, whereas the nodule in the right upper lobe shows relatively slow growth during 12 months. (B) Endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) performed at lymph node station #4R. (C) Rapid on‐site evaluation suspected small cell carcinoma (×200). (D) Histopathological examination of the lesion in the right upper lobe obtained using transbronchial biopsy demonstrating non‐small cell lung cancer (×50).

The procedure was performed under conscious sedation using midazolam and fentanyl. EBUS‐TBNA was initially performed at lymph node station #4R using a convex‐probe bronchoscope (BF‐UC290F; Olympus, Japan). Rapid on‐site evaluation (ROSE) suggested SCLC; the procedure was completed after three needle passes (Figure 1B,C). Because ROSE suggested SCLC, for which prompt treatment initiation is clinically important, we proceeded with additional bronchoscopic biopsy of the right upper lobe lesion during the same session to establish a definitive diagnosis.

For the lesion in the right upper lobe, a transbronchial biopsy (TBB) was planned using standard forceps with a thin bronchoscope (TB; BF‐P290, Olympus, Japan). The initial advancement of the TB was limited to the B³a bronchus. We attempted further peripheral advancement using the novel BDBD technique.

A bronchial dilation balloon catheter with a maximum inflated diameter of 5.0‐mm (BR‐N1 [SUKEDACHI]; Kaneka Medix, Japan) was introduced through the 2.0‐mm working channel of the TB and used to facilitate the ‘close‐to‐the‐lesion’ (CL) method. Sequential balloon dilation was performed for 20 s at B³a, followed by an additional 20 s at B³ai. This BDBD‐assisted approach enabled TB progression through an additional two bronchial generations. Consequently, a bronchial tumour with prominent vascular proliferation was directly visualized at the periphery of B³ai (Figure 2). As the lesion could be accessed using the CL method with the TB, a biopsy with standard forceps was feasible without fluoroscopic guidance. ROSE touch print cytology suggested NSCLC; the procedure was completed after five biopsy passes. EBUS‐TBNA and BDBD‐assisted TBB were successfully performed under conscious sedation with midazolam (total dose, 9 mg) and fentanyl (total dose, 0.09 mg) and topical lidocaine. Midazolam was initially administered at a dose of 2 mg and administered incrementally under continuous respiratory and circulatory status monitoring. The patient was reversed with flumazenil after the procedure. No sedation‐related or procedure‐related adverse events occurred. Procedure duration was 20 min for EBUS‐TBNA and 31 min for BDBD‐assisted TBB, respectively.

FIGURE 2.

Sequential bronchoscopic images of the BDBD technique. Balloon dilation at B³a enabled advancement into the B³ai branchi. Subsequent dilation at B³ai facilitated further peripheral advancement of the thin bronchoscope, allowing direct visualization of the target lesion. An endobronchial lesion with prominent vascular proliferation is directly visualized at the peripheral B³ai bronchus, allowing biopsy with standard forceps.

Histopathological examination of the EBUS‐TBNA specimen confirmed SCLC, whereas specimens obtained from the lesion in the right upper lobe confirmed NSCLC (Figure 1D). Based on the positron emission tomography–CT findings, the final diagnosis was extensive‐disease SCLC (ED‐SCLC), staged as cT2aN2M1b (Stage IV). The nodule in the right upper lobe was diagnosed as a synchronous primary NSCLC, staged as cT1cN0M0 (Stage IA3).

ED‐SCLC was considered the dominant prognostic determinant; therefore, systemic therapy with carboplatin, etoposide and durvalumab was initiated. The patient achieved a partial response following induction therapy after four cycles.

3. Discussion

Based on our experience with this single case, EBUS‐TBNA and BDBD can be performed within the same procedure to diagnose multiple primary lung cancers; BDBD itself appears to be minimally invasive and well‐tolerated in conscious sedation. Miyake et al. developed a balloon catheter for peripheral bronchial dilation using BDBD and applied it to diagnostic bronchoscopy procedures [1]. They also described a method for visualizing peripheral pulmonary lesions (PPLs) using ultrathin bronchoscope. In our institution's clinical practice, when performing TBB, we aim to obtain specimens using standard forceps whenever feasible as the difference in tissue volume compared with small forceps is clinically meaningful. The specimen size obtained using standard forceps is approximately 2 mm² [5], whereas that obtained using small forceps is 1 mm² [6]. However, when diagnosing PPLs, the reproducible advancement of a TB sufficiently close to the target lesion is challenging in some cases. The CL method, in which the bronchoscope tip is advanced as close as possible to the target lesion before TBB, is known to improve histopathological diagnostic yield and suitability of biopsy specimens for genetic testing. Nishii et al. defined tissue sampling as CL‐TBB when the bronchoscope tip was positioned within 10 mm of the lesion under fluoroscopic guidance [7]. In the present case, BDBD method facilitated further peripheral advancement of the bronchoscope and CL, allowing direct visualization during biopsy of the target lesion. BDBD may help overcome this limitation in select cases by enabling further advancements of the bronchoscope into the peripheral airways. In selected cases, BDBD may also be combined with navigation or lesion‐localization modalities to facilitate closer access to the target lesion. Its ability to facilitate direct visualization of peripheral lesions may have potential applications beyond tissue diagnosis, potentially expanding its role towards therapeutic bronchoscopy, including bronchoscopic local ablative treatments in the future. The bronchoscope used in the present case had an outer diameter of 4.2‐mm; however, SUKEDACHI balloon catheters with diameters of 4.5 or 5.0‐mm could be selected. The lesion in this case was centrally located; therefore, to enhance bronchial dilating force, we deliberately stepped up to a 5.0‐mm balloon from the outset. However, further case accumulation is necessary to establish optimal balloon selection. Moreover, the reported clinical utility of this balloon catheter remains limited [2, 3, 4]; additional clinical experience is required. In this case, BDBD was performed during the same session as EBUS‐TBNA. However, careful attention to procedural safety is warranted when combining these techniques.

In the present case, combining EBUS‐TBNA and BDBD enabled histopathological confirmation of synchronous SCLC and NSCLC during a single bronchoscopic session. This strategy avoided a second bronchoscopy, facilitated prompt initiation of treatment for SCLC, and enabled direct visualization and biopsy of the peripheral lesion using standard forceps. Although additional studies are required, this multimodality bronchoscopic approach may be a useful diagnostic option for selected patients with multiple pulmonary lesions.

Author Contributions

Keisuke Shiraha and Yuki Takigawa wrote the manuscript, which was reviewed by all the co‐authors. All authors have approved the final version of the manuscript for submission.

Funding

The authors have nothing to report.

Consent

Written informed consent was obtained from the patient for the publication of this manuscript and the accompanying images in accordance with the journal requirements.

Conflicts of Interest

Yuki Takigawa received speaker fees from AMCO Inc. and Pulmonx, Japan. Ken Sato received speaker fees from Olympus Marketing Inc., Kaneka Medix Co., and AMCO Inc. The other authors declare no conflicts of interest.

Shiraha K., Takigawa Y., Furutaguchi M., et al., “Diagnosis of Synchronous Primary Lung Cancers Using EBUS‐TBNA and BDBD‐Assisted Transbronchial Biopsy During a Single Bronchoscopic Procedure: A Case Report,” Respirology Case Reports 14, no. 9 (2026): e70743, 10.1002/rcr2.70743.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.