Question

What is the T stage of a 2.5cm lung carcinoma, not involving the pleura?

• A. T_1a
• B. T₂
• C. T_1b
• D. T_1c

Answer 1

The Correct Option is D

Use the simple size ladder: In the 8th edition TNM for lung cancer, a tumour up to 3 cm with no pleural or bronchial involvement is T1, and the only thing that separates T1a, T1b and T1c is size, in 1 cm steps.

Place the 2.5 cm tumour: One centimetre or less is T1a, up to 2 cm is T1b, and over 2 cm up to 3 cm is T1c. A 2.5 cm lesion sits squarely in the over 2 to 3 cm slot, so it is T1c.

Rule out the rest: T1a and T1b cover only tumours of 2 cm or less, so a 2.5 cm mass cannot be either. T2 needs a size above 3 cm or upstaging features such as visceral pleural invasion or main bronchus involvement, and the stem explicitly says the pleura is spared, so T2 is excluded.

Memory hook: For T1, think 1, 2, 3 cm equals a, b, c. Match the number to the letter and the staging is automatic.

Ref: Bailey and Love, Short Practice of Surgery, 27e, Pg 927.