This is a case of a 75-year-old male who presented to our hospital with a three month history of worsening shortness of breath and reduced exercise tolerance. He described a 25kg weight loss and had a 65-pack-year history of smoking.

This gentleman underwent a pleuritic tap which confirmed malignant adenocarcinoma.

MACROSCOPIC:

• Received 50ml of cloudy yellow fluid with clots.

MICROSCOPIC:

• Moderate cellularity
• Malignant cells are present in a background of leukocytes (predominantly lymphocytes), histiocytes and blood
• Malignant cells have markedly pleomorphic, hyperchromatic nuclei and moderate amounts of cytoplasm

IMMUNOHISTOCHEMISTRY:

• Positive: AE1/3, CEA, TTF1
• Negative: BerEp4, calretinin, WT1, CK5/6  

Features are consistent with metastatic adenocarcinoma of pulmonary origin.

He has now been referred to medical oncologists for ongoing treatment.