28th February 2025

A 50-year-old lady presents with a 2-month history of a new cough. She has no pre-existing medical conditions

A 50-year-old lady presents with a 2-month history of a new cough. She has no pre-existing medical conditions. Initial chest X-ray reveals a central cavitating mass of the right lung, and an urgent biopsy is planned. While awaiting the results she develops pain and stiffness in both wrists. She has been taking ibuprofen and reports this has provided some relief. She is otherwise well with no other symptoms to report.

On examination, both wrists are swollen and tender to palpate. Range of movement is significantly limited by pain bilaterally. Digital clubbing is also noted.

Initial blood tests are negative for rheumatoid factor, anti-citrullinated protein antibodies and antinuclear antibodies.

What is the most likely cause of this lady’s symptoms?

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