Which of the following best characterises the T3 stage of muscle-invasive bladder cancer according to the TNM classification?

• A Tumour invades the lamina propria (subepithelial connective tissue) only
• B Tumour invades the muscularis propria (detrusor muscle)
• C Tumour invades the perivesical tissue — T3a microscopically, T3b macroscopically ✓
• D Tumour invades adjacent pelvic organs such as uterus, prostate stroma, or pelvic wall

Explanation

TNM bladder staging: T1 — lamina propria invasion; T2a — inner half of muscularis propria; T2b — outer half of muscularis propria; T3a — microscopic perivesical fat invasion; T3b — macroscopic perivesical fat invasion (extravesical mass visible on imaging/pathology); T4a — invasion of adjacent organs (prostate stroma, seminal vesicles, uterus, vagina); T4b — invasion of pelvic or abdominal wall. Option C correctly defines T3 with the T3a/T3b subcategories.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.