21st February 2025

A 59-year-old man with metastatic lung adenocarcinoma who has been on palliative carboplatin and paclitaxel treatment for the last 6 months presents with a 1-week history of acutely worsening breathlessness and cough.

A 59-year-old man with metastatic lung adenocarcinoma who has been on palliative carboplatin and paclitaxel treatment for the last 6 months presents with a 1-week history of acutely worsening breathlessness and cough. A CT chest demonstrates slight growth of the primary cancer with new patchy areas of interlobular septal thickening. 

What is the most likely cause of the patient’s worsening breathlessness?

Select the SINGLE most appropriate option from the list below. Select ONE option only.