During intracavitary brachytherapy planning for cervical cancer, Point A is conventionally located at which position relative to the cervical os?
- A 5 cm lateral to the midline at the level of the acetabulum
- B 2 cm superior and 2 cm lateral to the external cervical os ✓
- C At the vaginal fornix, 1 cm below the external os
- D Midway between the uterine fundus and the sacral promontory
Correct answer: B. 2 cm superior and 2 cm lateral to the external cervical os
Explanation
Point B lies 2 cm above the external os in the plane of the uterus and 2 cm lateral to the midline, approximating the paracervical tissues where the uterine vessels cross the ureter. It is the classical prescription point for the target dose. Point A, 3 cm further lateral, represents the obturator and pelvic sidewall nodes. The other descriptions correspond to no standard brachytherapy reference point.
Reference: Berek and Novak's Gynecology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.