Adamantia Liapikou

Pulmonary actinomycosis and pulmonary nocardiosis are rare chronic respiratory infections that may closely resemble lung cancer due to their overlapping clinical, radiological, and bronchoscopic characteristics. This hybrid case series and narrative review aims to elucidate the presenting patterns, diagnostic pathways, management strategies, and practical implications of these infections in the differential diagnosis of lung cancer. We analyzed four consecutive cases managed at the Sotiria Thoracic Diseases General Hospital in Athens from 2021 to 2025, supplemented by eight additional cases identified through a review of Greek grey literature from the same period. In the 12 cases reviewed, patients commonly presented with cough, dyspnea, fever, hemoptysis, malaise, and weight loss. Chest imaging frequently revealed consolidation, cavitation, atelectasis, nodules, or mediastinal lymphadenopathy, often prompting an oncological evaluation. Bronchoscopic findings occasionally mimicked malignant submucosal spread, and increased fluorodeoxyglucose uptake added to the diagnostic uncertainty. Notably, one case exhibited coexistence of pulmonary actinomycosis with lung adenocarcinoma. Microbiological and histopathological evaluations confirmed the diagnoses, and most patients showed clinical and radiological improvement following prolonged targeted antimicrobial therapy. Given these findings, pulmonary actinomycosis and nocardiosis should be considered in patients with suspected lung cancer, particularly when infectious features coexist with mass-like or cavitary lesions. Careful tissue sampling, specialized microbiological testing, and structured follow-up are essential for excluding occult or coexisting malignancy.

SWItch/sucrose non-fermentable (SWI/SNF) is a large protein complex with a central role in chromatin remodeling and genome transcription. The catalytic subunits of the SWI/SNF related BAF chromatin remodeling complex subunit ATPase 2 (SWI/SNF SMARCA2; also called BRM) and SWI/SNF related BAF chromatin remodeling complex subunit ATPase 4 (SMARCA4; also called BRG1) are encoded by the SMARCA2 and SMARCA4 genes, respectively, and are mutually exclusive. Loss of either SMARCA2 and/or SMARCA4 has been previously reported in several types of malignant solid tumors of the gastrointestinal and genitourinary tract. So far, their absence in non-small cell lung cancer (SCLC) has been observed in a series of studies involving primary tumors and cell lines, where it is associated with loss of differentiation and heightened tumorigenic potential leading to an unfavorable prognosis. SMARCA2 and SMARCA4 deficiency is frequent in solid predominant adenocarcinomas and tumors with low levels of bronchial epithelial markers, including thyroid transcription factor 1. A rare case of SMARCA4 deficiency in SCLC is described. A 57-year-old male patient, with no medical history of past illness, was admitted to our center for the investigation and management of a space-occupying lesion in the right upper lung lobe with tracheal and mediastinal infiltration. Biopsy of a lymph node in the right supraclavicular region was diagnostic for SCLC with regional loss of SMARCA4. The patient demonstrated progressive respiratory failure and clinical deterioration and eventually deceased despite intubation and transfer to the intensive care unit. This case indicates that SMARCA4-deficient SCLC may present with an aggressively deteriorating phenotype with poor outcomes for the patients.

Bronchiectasis is a heterogeneous chronic lung disease, characterised by irreversible dilatation of the airways and attributed to a wide spectrum of other underlying conditions, usually underdiagnosed and inadequately treated with a high burden for both the patients and the healthcare system. The way bronchiectasis is viewed by physicians has drastically changed over the last decades, with the topic of eosinophilia in the context of the disease being one of the substantially highlighted. Eosinophilia was traditionally considered as a means for distinguishing bronchiectasis from asthma, whereas bronchiectasis was primarily associated with neutrophilic inflammation. However, eosinophilic bronchiectasis is nowadays identified as a distinct disease endotype and is associated with a specific clinical course and response to treatment. Further research is needed to better characterise this endotype and improve its personalised investigation and management in daily clinical practice.