Gynaecological oncology: PARP inhibitor mechanism: 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: PARP inhibitor mechanism

Sample item

In a woman with BRCA-mutated high-grade serous ovarian cancer responding to platinum chemotherapy, maintenance olaparib acts by which mechanism?

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

The answer and the reasoning

A. Synthetic lethality in homologous-recombination-deficient cells

PARP inhibitors block repair of single-strand breaks, which become double-strand breaks at replication. Cells lacking BRCA cannot repair them by homologous recombination and die, while normal cells survive.

Option by option

  • A. Synthetic lethality in homologous-recombination-deficient cells (correct)

    Correct. Blocking PARP is lethal to cells already deficient in homologous recombination.

  • B. Blocking VEGF-driven angiogenesis

    Blocking VEGF is the action of bevacizumab.

  • C. Cross-linking DNA strands

    DNA cross-linking is the action of platinum agents.

  • D. Stabilising microtubules in mitosis

    Microtubule stabilisation is the action of paclitaxel.

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.

More OBG questions

Questions about this OBG question

What is the answer to this OBG question?

The best answer is A, Synthetic lethality in homologous-recombination-deficient cells. PARP inhibitors block repair of single-strand breaks, which become double-strand breaks at replication.

Why is "Blocking VEGF-driven angiogenesis" not the answer?

Blocking VEGF is the action of bevacizumab.

Why is "Cross-linking DNA strands" not the answer?

DNA cross-linking is the action of platinum agents.

Why is "Stabilising microtubules in mitosis" not the answer?

Microtubule stabilisation is the action of paclitaxel.

What concept does this question test?

It tests Gynaecological oncology: PARP inhibitor mechanism in OBG. Cells lacking BRCA cannot repair them by homologous recombination and die, while normal cells survive.

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: PARP inhibitor mechanism?

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.