Pattern of Pulmonary Metastases in Various Malignancies

Background: Metastases from extrathoracic malignancies most commonly spread to the lungs as the second most prevalent site. Detecting metastases can indicate the necessity of chemotherapy or surgical removal. Conversely, ruling out pulmonary metastases is vital for planning a potentially curative treatment, highlighting the importance of understanding the imaging characteristics of lung metastases. This study aims to determine the different patterns of pulmonary metastases in various malignancies. Materials and methods: A hospital-based observational study was conducted at Department of Respiratory Medicine, A.J Institute of Medical Sciences and Mangalore Institute of Oncology, Mangalore. The study included 50 consecutive cases of diagnosed extra-thoracic malignancies with intrathoracic metastases attending our hospital. Screening of the cases with primary neoplasms was done as per the American College of Radiology (ACR) Appropriateness Criteria. The data was initially inputted into a Microsoft Excel spreadsheet and subsequently imported into SPSS software, version 24.0, for statistical analysis. Results: The most common site of primary malignancy was breast carcinoma (40%) followed by colorectal carcinoma (CRC) (14%), renal cell carcinoma (RCC) (10%), pancreatic carcinoma (8%), and oesophageal carcinoma (6%). Most common histopathological subtype of primary malignancy was infiltrating ductal carcinoma (40%) followed by adenocarcinoma (34%), squamous cell carcinoma (14%), clear cell carcinoma (10%), and follicular cell carcinoma (2%). Most common presenting respiratory symptom was breathlessness (54%) and cough (42%). The common findings seen on CT lung were pleural effusion (52%) and multiple pulmonary nodules (50%). Conclusion: Recognising the pulmonary metastases pattern is pivotal for early detection and individualised management. Comprehensive patient care, encompassing clinical, imaging, and a multi-disciplinary approach, is vital for improved patient outcomes.