Gynaecological oncology: brachytherapy points: practice question

A OBG question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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OBG · Gynaecological oncology: brachytherapy points

Sample item

In the Manchester system for intracavitary radiotherapy in cervical cancer, where is point A located?

AAt the pelvic side wallB3 cm below the vaginal vaultCAt the cervical osD2 cm above the lateral vaginal fornix and 2 cm lateral to the cervical canal

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

D. 2 cm above the lateral vaginal fornix and 2 cm lateral to the cervical canal

Point A lies 2 cm superior to the lateral fornix and 2 cm lateral to the central uterine canal, near where the uterine artery crosses the ureter, and it represents the paracervical triangle. Point B is 3 cm lateral to A at the pelvic wall and represents the obturator nodes. Doses to A and B are used for planning and for limiting toxicity.

Option by option

A. At the pelvic side wall
The pelvic side wall is point B.
B. 3 cm below the vaginal vault
Point A is above, not below, the vaginal fornix.
C. At the cervical os
The os itself is not point A.
D. 2 cm above the lateral vaginal fornix and 2 cm lateral to the cervical canal (correct)
Correct. Point A is 2 cm above the fornix and 2 cm lateral to the canal.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this OBG question

What is the answer to this OBG question?

The best answer is D, 2 cm above the lateral vaginal fornix and 2 cm lateral to the cervical canal. Point A lies 2 cm superior to the lateral fornix and 2 cm lateral to the central uterine canal, near where the uterine artery crosses the ureter, and it represents the paracervical triangle.

Why is "At the pelvic side wall" not the answer?

The pelvic side wall is point B.

Why is "3 cm below the vaginal vault" not the answer?

Point A is above, not below, the vaginal fornix.

Why is "At the cervical os" not the answer?

The os itself is not point A.

What concept does this question test?

It tests Gynaecological oncology: brachytherapy points in OBG. Point B is 3 cm lateral to A at the pelvic wall and represents the obturator nodes. Doses to A and B are used for planning and for limiting toxicity.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Gynaecological oncology: brachytherapy points?

Learn management algorithms as steps: PPH, eclampsia, ectopic pregnancy. Then use the flashcards and the other OBG questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.