Small-cell lung cancer (SCLC) is an aggressive malignancy with poor prognosis despite initial responsiveness to chemotherapy. Platinum-based chemotherapy with etoposide has long been the standard first-line treatment, but recent advances in immunotherapy have improved outcomes. Phase III trials, including IMpower133 and CASPIAN, demonstrated that adding immune checkpoint inhibitors, such as atezolizumab and durvalumab, to chemotherapy significantly enhances overall survival (OS) and progression-free survival (PFS). This case report describes a 76-year-old former smoker diagnosed with extensive-stage SCLC (ES-SCLC) following the detection of a left lower lung mass. The patient underwent combination therapy with carboplatin, etoposide, and atezolizumab, followed by maintenance atezolizumab. The patient demonstrated a sustained response to treatment, with significant tumor regression and no evidence of disease progression. Despite advanced age and comorbidities, treatment was well-tolerated, with no severe adverse events. Serial imaging over 24 months confirmed sustained disease stability, with regression of mediastinal lymphadenopathy and no new lesions. This case highlights the potential for prolonged disease control in select SCLC patients treated with chemo-immunotherapy. The absence of significant toxicities underscores the feasibility of immunotherapy even in elderly patients with comorbidities. These findings support the role of atezolizumab as a key component of ES-SCLC treatment and suggest the need for further research on predictors of durable response.

Over the past 40 years, thoracic ultrasound (TUS) has relied predominantly on the analysis of artefacts generated by the marked acoustic impedance mismatch between the chest wall and pulmonary air. However, ambiguous terminology has often conflated distinct physical phenomena, compromising their diagnostic utility. This review explores the physical basis underlying the genesis of vertical artefacts (B-lines), starting from the theory of ultrasound propagation in aerated parenchyma. The first comprehensive description of vertical artefacts in pulmonary pathology, termed “radiating streaks”, dates back to 1986. Furthermore, a strict distinction is emphasised between pure, rapidly decaying reverberation phenomena (comet-tail) and resonance phenomena (ring-down or B-lines). By analysing different scenarios, we demonstrate that semantic confusion, combined with an alphabetical nomenclature, has led to an overestimation of the diagnostic potential of TUS artefacts. Although B-lines represent physical artefacts rather than direct anatomical images, they retain valuable clinical utility. For instance, they serve as a rapid screening and diagnostic triage tool in emergency settings, raising the suspicion of underlying pulmonary pathologies (e.g., acute pulmonary oedema, pulmonary fibrosis, or ARDS). “B-lines” on TUS are the manifestation of acoustic phenomena (artefacts) that are also present in the residual cavity of patients who have undergone pneumonectomy, as well as in the abdominal region. These artefacts depend primarily on the soft tissue/air–fluid interface—as demonstrated by the absence of vertical artefacts during intraoperative ultrasound—and not on any actual interstitial anatomical alteration. By analysing different scenarios, this review criticises the overestimation of the diagnostic potential of TUS artefacts. We must move beyond the semi-quantitative counting of these artefacts in favour of an integrated interpretation that acknowledges the physical limitations of the method, thereby avoiding the transformation of a simple TUS software error into a specific pathological measurement.